Load jpegs without gdk-pixbuf

Use our own loader for jpeg files.

gdk/gdkcontentdeserializer.c

@@ -25,6 +25,8 @@
 #include "filetransferportalprivate.h"
 #include "gdktexture.h"
 #include "gdkrgbaprivate.h"
+#include "gdkpng.h"
+#include "gdktiff.h"
 
 #include <gdk-pixbuf/gdk-pixbuf.h>
 
@@ -655,6 +657,66 @@ pixbuf_deserializer (GdkContentDeserializer *deserializer)
                                     deserializer);
 }
 
+static void
+png_deserializer_finish (GObject      *source,
+                         GAsyncResult *res,
+                         gpointer      deserializer)
+{
+  GdkTexture *texture;
+  GValue *value;
+  GError *error = NULL;
+
+  texture = gdk_load_png_finish (res, &error);
+  if (texture == NULL)
+    {
+      gdk_content_deserializer_return_error (deserializer, error);
+      return;
+    }
+
+  value = gdk_content_deserializer_get_value (deserializer);
+  g_value_take_object (value, texture);
+  gdk_content_deserializer_return_success (deserializer);
+}
+
+static void
+png_deserializer (GdkContentDeserializer *deserializer)
+{
+  gdk_load_png_async (gdk_content_deserializer_get_input_stream (deserializer),
+                      gdk_content_deserializer_get_cancellable (deserializer),
+                      png_deserializer_finish,
+                      deserializer);
+}
+
+static void
+tiff_deserializer_finish (GObject      *source,
+                          GAsyncResult *res,
+                          gpointer      deserializer)
+{
+  GdkTexture *texture;
+  GValue *value;
+  GError *error = NULL;
+
+  texture = gdk_load_tiff_finish (res, &error);
+  if (texture == NULL)
+    {
+      gdk_content_deserializer_return_error (deserializer, error);
+      return;
+    }
+
+  value = gdk_content_deserializer_get_value (deserializer);
+  g_value_take_object (value, texture);
+  gdk_content_deserializer_return_success (deserializer);
+}
+
+static void
+tiff_deserializer (GdkContentDeserializer *deserializer)
+{
+  gdk_load_tiff_async (gdk_content_deserializer_get_input_stream (deserializer),
+                       gdk_content_deserializer_get_cancellable (deserializer),
+                       tiff_deserializer_finish,
+                       deserializer);
+}
+
 static void
 string_deserializer_finish (GObject      *source,
                             GAsyncResult *result,
@@ -863,27 +925,38 @@ init (void)
 
   initialized = TRUE;
 
+  gdk_content_register_deserializer ("image/png",
+                                     GDK_TYPE_TEXTURE,
+                                     png_deserializer,
+                                     NULL,
+                                     NULL);
+
+  gdk_content_register_deserializer ("image/tiff",
+                                     GDK_TYPE_TEXTURE,
+                                     tiff_deserializer,
+                                     NULL,
+                                     NULL);
+
   formats = gdk_pixbuf_get_formats ();
 
   /* Make sure png comes first */
   for (f = formats; f; f = f->next)
     {
       GdkPixbufFormat *fmt = f->data;
-      char *name; 
- 
+      char *name;
+
       name = gdk_pixbuf_format_get_name (fmt);
       if (g_str_equal (name, "png"))
-	{
-	  formats = g_slist_delete_link (formats, f);
-	  formats = g_slist_prepend (formats, fmt);
+        {
+          formats = g_slist_delete_link (formats, f);
+          formats = g_slist_prepend (formats, fmt);
 
-	  g_free (name);
-
-	  break;
-	}
+          g_free (name);
+          break;
+        }
 
       g_free (name);
-    }  
+    }
 
   for (f = formats; f; f = f->next)
     {

gdk/gdkcontentserializer.c

@@ -26,6 +26,9 @@
 #include "filetransferportalprivate.h"
 #include "gdktextureprivate.h"
 #include "gdkrgba.h"
+#include "gdkpng.h"
+#include "gdktiff.h"
+#include "gdkmemorytextureprivate.h"
 
 #include <gdk-pixbuf/gdk-pixbuf.h>
 #include <string.h>
@@ -606,6 +609,7 @@ gdk_content_serialize_finish (GAsyncResult  *result,
 
 /*** SERIALIZERS ***/
 
+
 static void
 pixbuf_serializer_finish (GObject      *source,
                           GAsyncResult *res,
@@ -658,6 +662,132 @@ pixbuf_serializer (GdkContentSerializer *serializer)
   g_object_unref (pixbuf);
 }
 
+typedef struct {
+  GdkContentSerializer *serializer;
+  GBytes *bytes;
+} PngSerializerData;
+
+static void
+png_serializer_finish (GObject      *source,
+                       GAsyncResult *res,
+                       gpointer      user_data)
+{
+  PngSerializerData *data = user_data;
+  GError *error = NULL;
+
+  if (!gdk_save_png_finish (res, &error))
+    gdk_content_serializer_return_error (data->serializer, error);
+  else
+    gdk_content_serializer_return_success (data->serializer);
+
+  g_bytes_unref (data->bytes);
+  g_free (data);
+}
+
+static void
+png_serializer (GdkContentSerializer *serializer)
+{
+  const GValue *value;
+  GdkTexture *texture;
+  GdkMemoryFormat format;
+  GBytes *bytes = NULL;
+  PngSerializerData *data;
+
+  value = gdk_content_serializer_get_value (serializer);
+
+  texture = g_value_get_object (value);
+
+  for (int i = 0; i < GDK_MEMORY_N_FORMATS; i++)
+    {
+      bytes = gdk_texture_download_format (texture, i);
+      if (bytes)
+        {
+          format = i;
+          break;
+        }
+    }
+
+  g_assert (bytes != NULL);
+
+  data = g_new0 (PngSerializerData, 1);
+  data->serializer = serializer;
+  data->bytes = bytes;
+
+  gdk_save_png_async (gdk_content_serializer_get_output_stream (serializer),
+                      g_bytes_get_data (bytes, NULL),
+                      gdk_texture_get_width (texture),
+                      gdk_texture_get_height (texture),
+                      gdk_texture_get_width (texture) * gdk_memory_format_bytes_per_pixel (format),
+                      format,
+                      gdk_content_serializer_get_cancellable (serializer),
+                      png_serializer_finish,
+                      data);
+  g_object_unref (texture);
+}
+
+typedef struct {
+  GdkContentSerializer *serializer;
+  GBytes *bytes;
+} TiffSerializerData;
+
+static void
+tiff_serializer_finish (GObject      *source,
+                        GAsyncResult *res,
+                        gpointer      user_data)
+{
+  TiffSerializerData *data = user_data;
+  GError *error = NULL;
+
+  if (!gdk_save_tiff_finish (res, &error))
+    gdk_content_serializer_return_error (data->serializer, error);
+  else
+    gdk_content_serializer_return_success (data->serializer);
+
+  g_bytes_unref (data->bytes);
+  g_free (data);
+}
+
+static void
+tiff_serializer (GdkContentSerializer *serializer)
+{
+  const GValue *value;
+  GdkTexture *texture;
+  GdkMemoryFormat format;
+  GBytes *bytes = NULL;
+  TiffSerializerData *data;
+
+  value = gdk_content_serializer_get_value (serializer);
+
+  texture = g_value_get_object (value);
+
+  for (int i = 0; i < GDK_MEMORY_N_FORMATS; i++)
+    {
+      bytes = gdk_texture_download_format (texture, i);
+      if (bytes)
+        {
+          format = i;
+          break;
+        }
+    }
+
+  g_assert (bytes != NULL);
+
+  data = g_new0 (TiffSerializerData, 1);
+  data->serializer = serializer;
+  data->bytes = bytes;
+
+  gdk_save_tiff_async (gdk_content_serializer_get_output_stream (serializer),
+                       g_bytes_get_data (bytes, NULL),
+                       gdk_texture_get_width (texture),
+                       gdk_texture_get_height (texture),
+                       gdk_texture_get_width (texture) * gdk_memory_format_bytes_per_pixel (format),
+                       format,
+                       gdk_content_serializer_get_cancellable (serializer),
+                       tiff_serializer_finish,
+                       data);
+  g_object_unref (texture);
+}
+
 static void
 string_serializer_finish (GObject      *source,
                           GAsyncResult *result,
@@ -877,27 +1007,36 @@ init (void)
 
   initialized = TRUE;
 
+  gdk_content_register_serializer (GDK_TYPE_TEXTURE,
+                                   "image/png",
+                                   png_serializer,
+                                   NULL, NULL);
+
+  gdk_content_register_serializer (GDK_TYPE_TEXTURE,
+                                   "image/tiff",
+                                   tiff_serializer,
+                                   NULL, NULL);
+
   formats = gdk_pixbuf_get_formats ();
 
   /* Make sure png comes first */
   for (f = formats; f; f = f->next)
     {
       GdkPixbufFormat *fmt = f->data;
-      char *name; 
- 
+      char *name;
+
       name = gdk_pixbuf_format_get_name (fmt);
       if (g_str_equal (name, "png"))
-	{
-	  formats = g_slist_delete_link (formats, f);
-	  formats = g_slist_prepend (formats, fmt);
+        {
+          formats = g_slist_delete_link (formats, f);
+          formats = g_slist_prepend (formats, fmt);
 
-	  g_free (name);
-
-	  break;
-	}
+          g_free (name);
+          break;
+        }
 
       g_free (name);
-    }  
+    }
 
   for (f = formats; f; f = f->next)
     {

gdk/gdkglcontext.c

@@ -278,6 +278,48 @@ gdk_gl_context_upload_texture (GdkGLContext    *context,
           gl_type = GL_UNSIGNED_BYTE;
           bpp = 3;
         }
+      else if (data_format == GDK_MEMORY_R16G16B16)
+        {
+          gl_internalformat = GL_RGBA16;
+          gl_format = GL_RGB;
+          gl_type = GL_UNSIGNED_SHORT;
+          bpp = 6;
+        }
+      else if (data_format == GDK_MEMORY_R16G16B16A16_PREMULTIPLIED)
+        {
+          gl_internalformat = GL_RGBA16;
+          gl_format = GL_RGBA;
+          gl_type = GL_UNSIGNED_SHORT;
+          bpp = 8;
+        }
+      else if (data_format == GDK_MEMORY_R16G16B16_FLOAT)
+        {
+          gl_internalformat = GL_RGB16F;
+          gl_format = GL_RGB;
+          gl_type = GL_HALF_FLOAT;
+          bpp = 6;
+        }
+      else if (data_format == GDK_MEMORY_R16G16B16A16_FLOAT_PREMULTIPLIED)
+        {
+          gl_internalformat = GL_RGBA16F;
+          gl_format = GL_RGBA;
+          gl_type = GL_HALF_FLOAT;
+          bpp = 8;
+        }
+      else if (data_format == GDK_MEMORY_R32G32B32_FLOAT)
+        {
+          gl_internalformat = GL_RGB32F;
+          gl_format = GL_RGB;
+          gl_type = GL_FLOAT;
+          bpp = 12;
+        }
+      else if (data_format == GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED)
+        {
+          gl_internalformat = GL_RGBA32F;
+          gl_format = GL_RGBA;
+          gl_type = GL_FLOAT;
+          bpp = 16;
+        }
       else /* Fall-back, convert to cairo-surface-format */
         {
           copy = g_malloc (width * height * 4);

gdk/gdkgltexture.c

@@ -22,6 +22,8 @@
 
 #include "gdkcairo.h"
 #include "gdktextureprivate.h"
+#include "gdkmemorytextureprivate.h"
+#include "gdkinternals.h"
 
 #include <epoxy/gl.h>
 
@@ -110,6 +112,78 @@ gdk_gl_texture_download (GdkTexture         *texture,
   cairo_surface_destroy (surface);
 }
 
+static int
+type_from_internal_format (int internal_format)
+{
+  switch (internal_format)
+    {
+    case GL_RGB16:
+    case GL_RGBA16:
+      return GL_UNSIGNED_SHORT;
+    case GL_RGB16F:
+    case GL_RGBA16F:
+      return GL_HALF_FLOAT;
+    case GL_RGB32F:
+    case GL_RGBA32F:
+      return GL_FLOAT;
+    default:
+      g_assert_not_reached ();
+    }
+}
+
+static int
+internal_format_for_format (GdkMemoryFormat format)
+{
+  switch ((int)format)
+    {
+    case GDK_MEMORY_R16G16B16:
+      return GL_RGB16;
+    case GDK_MEMORY_R16G16B16A16_PREMULTIPLIED:
+      return GL_RGBA16;
+    case GDK_MEMORY_R16G16B16_FLOAT:
+      return GL_RGB16F;
+    case GDK_MEMORY_R16G16B16A16_FLOAT_PREMULTIPLIED:
+      return GL_RGB16F;
+    case GDK_MEMORY_R32G32B32_FLOAT:
+      return GL_RGB32F;
+    case GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED:
+      return GL_RGB32F;
+    default:
+      g_assert_not_reached ();
+    }
+}
+
+static GBytes *
+gdk_gl_texture_download_format (GdkTexture      *texture,
+                                GdkMemoryFormat  format)
+{
+  GdkGLTexture *self = GDK_GL_TEXTURE (texture);
+  GdkSurface *surface;
+  GdkGLContext *context;
+  int internal_format = 0;
+  gpointer data;
+  gsize size;
+
+  surface = gdk_gl_context_get_surface (self->context);
+  context = gdk_surface_get_paint_gl_context (surface, NULL);
+
+  gdk_gl_context_make_current (context);
+  glBindTexture (GL_TEXTURE_2D, self->id);
+  glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_INTERNAL_FORMAT, &internal_format);
+
+  if (internal_format != internal_format_for_format (format))
+    return NULL;
+
+  size = texture->width * texture->height * gdk_memory_format_bytes_per_pixel (format);
+  data = malloc (size);
+
+  glReadPixels (0, 0, texture->width, texture->height,
+                internal_format, type_from_internal_format (internal_format),
+                 data);
+
+  return g_bytes_new_take (data, size);
+}
+
 static void
 gdk_gl_texture_class_init (GdkGLTextureClass *klass)
 {
@@ -117,6 +191,7 @@ gdk_gl_texture_class_init (GdkGLTextureClass *klass)
   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 
   texture_class->download = gdk_gl_texture_download;
+  texture_class->download_format = gdk_gl_texture_download_format;
   gobject_class->dispose = gdk_gl_texture_dispose;
 }
 

gdk/gdkjpeg.c

@@ -0,0 +1,234 @@
+/* GDK - The GIMP Drawing Kit
+ * Copyright (C) 2021 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "gdkjpeg.h"
+
+#include "gdktexture.h"
+#include "gdkmemorytextureprivate.h"
+#include <jpeglib.h>
+#include <jerror.h>
+#include <setjmp.h>
+
+/* {{{ IO handling */
+
+#define BUF_SIZE 65536
+
+typedef struct {
+  struct jpeg_source_mgr pub;
+  JOCTET buffer[BUF_SIZE];
+  long skip_next;
+  GInputStream *stream;
+} my_source_mgr;
+
+static void
+init_source (j_decompress_ptr info)
+{
+  my_source_mgr *src = (my_source_mgr *) info->src;
+  src->skip_next = 0;
+}
+
+static void
+term_source (j_decompress_ptr info)
+{
+}
+
+static boolean
+fill_input_buffer (j_decompress_ptr info)
+{
+  my_source_mgr *src = (my_source_mgr *) info->src;
+  size_t nbytes;
+
+  nbytes = g_input_stream_read (src->stream, src->buffer, BUF_SIZE, NULL, NULL);
+
+  if (nbytes <= 0)
+    {
+      /* Insert a fake EOI marker */
+      src->buffer[0] = (JOCTET) 0xFF;
+      src->buffer[1] = (JOCTET) JPEG_EOI;
+      nbytes = 2;
+    }
+
+  src->pub.next_input_byte = src->buffer;
+  src->pub.bytes_in_buffer = nbytes;
+
+  return TRUE;
+}
+
+static void
+skip_input_data (j_decompress_ptr info,
+                 long             num_bytes)
+{
+  my_source_mgr *src = (my_source_mgr *) info->src;
+
+  if (num_bytes > 0)
+    {
+      while (num_bytes > src->pub.bytes_in_buffer)
+        {
+          num_bytes -= src->pub.bytes_in_buffer;
+          fill_input_buffer (info);
+        }
+
+      src->pub.next_input_byte += num_bytes;
+      src->pub.bytes_in_buffer -= num_bytes;
+    }
+}
+
+/* }}} */
+/* {{{ Error handling */
+
+struct error_handler_data {
+        struct jpeg_error_mgr pub;
+        sigjmp_buf setjmp_buffer;
+        GError **error;
+};
+
+static void
+fatal_error_handler (j_common_ptr cinfo)
+{
+  struct error_handler_data *errmgr;
+
+  errmgr = (struct error_handler_data *) cinfo->err;
+
+  siglongjmp (errmgr->setjmp_buffer, 1);
+
+  g_assert_not_reached ();
+}
+
+static void
+output_message_handler (j_common_ptr cinfo)
+{
+  /* do nothing */
+}
+
+/* }}} */
+ /* {{{ Public API */
+
+GdkTexture *
+gdk_load_jpeg (GInputStream  *stream,
+               GError       **error)
+{
+  struct jpeg_decompress_struct info;
+  struct error_handler_data jerr;
+  struct jpeg_error_mgr err;
+  my_source_mgr src;
+  int width, height;
+  int size;
+  unsigned char *data;
+  unsigned char *row[1];
+  GBytes *bytes;
+  GdkTexture *texture;
+
+  info.err = jpeg_std_error (&jerr.pub);
+  jerr.pub.error_exit = fatal_error_handler;
+  jerr.pub.output_message = output_message_handler;
+  jerr.error = error;
+
+  if (sigsetjmp (jerr.setjmp_buffer, 1))
+    {
+      jpeg_destroy_decompress (&info);
+      return NULL;
+    }
+
+  info.err = jpeg_std_error (&err);
+  jpeg_create_decompress (&info);
+
+  src.pub.init_source = init_source;
+  src.pub.fill_input_buffer = fill_input_buffer;
+  src.pub.skip_input_data = skip_input_data;
+  src.pub.resync_to_restart = jpeg_resync_to_restart;
+  src.pub.term_source = term_source;
+  src.pub.bytes_in_buffer = 0;
+  src.pub.next_input_byte = NULL;
+  src.stream = stream;
+
+  info.src = (struct jpeg_source_mgr *)&src;
+
+  jpeg_read_header (&info, TRUE);
+  jpeg_start_decompress (&info);
+
+  width = info.output_width;
+  height = info.output_height;
+
+  size = width * height * 3;
+  data = g_malloc (size);
+
+  while (info.output_scanline < info.output_height)
+    {
+       row[0] = (unsigned char *)(&data[3 *info.output_width * info.output_scanline]);
+       jpeg_read_scanlines (&info, row, 1);
+    }
+
+  jpeg_finish_decompress (&info);
+  jpeg_destroy_decompress (&info);
+
+  bytes = g_bytes_new_take (data, size);
+
+  texture = gdk_memory_texture_new (width, height,
+                                    GDK_MEMORY_R8G8B8,
+                                    bytes, width * 3);
+
+  g_bytes_unref (bytes);
+
+  return texture;
+}
+
+/* }}} */
+/* {{{ Async code */
+
+static void
+load_jpeg_in_thread (GTask        *task,
+                     gpointer      source_object,
+                     gpointer      task_data,
+                     GCancellable *cancellable)
+{
+  GInputStream *stream = source_object;
+  GdkTexture *texture;
+  GError *error = NULL;
+
+  texture = gdk_load_jpeg (stream, &error);
+
+  if (texture)
+    g_task_return_pointer (task, texture, g_object_unref);
+  else
+    g_task_return_error (task, error);
+}
+
+void
+gdk_load_jpeg_async (GInputStream         *stream,
+                     GCancellable         *cancellable,
+                     GAsyncReadyCallback   callback,
+                     gpointer              user_data)
+{
+  GTask *task;
+
+  task = g_task_new (stream, cancellable, callback, user_data);
+  g_task_run_in_thread (task, load_jpeg_in_thread);
+  g_object_unref (task);
+}
+
+GdkTexture *
+gdk_load_jpeg_finish (GAsyncResult  *result,
+                      GError       **error)
+{
+  return g_task_propagate_pointer (G_TASK (result), error);
+}
+
+/* }}} */
+
+/* vim:set foldmethod=marker expandtab: */

gdk/gdkjpeg.h

@@ -0,0 +1,35 @@
+/* GDK - The GIMP Drawing Kit
+ * Copyright (C) 2021 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GDK_JPEG_H__
+#define __GDK_JPEG_H__
+
+#include "gdkmemorytexture.h"
+#include <gio/gio.h>
+
+GdkTexture *gdk_load_jpeg         (GInputStream     *stream,
+                                   GError          **error);
+
+void        gdk_load_jpeg_async   (GInputStream           *stream,
+                                   GCancellable           *cancellable,
+                                   GAsyncReadyCallback     callback,
+                                   gpointer                user_data);
+
+GdkTexture *gdk_load_jpeg_finish  (GAsyncResult           *result,
+                                   GError                **error);
+
+#endif

gdk/gdkmemorytexture.c

@@ -20,6 +20,7 @@
 #include "config.h"
 
 #include "gdkmemorytextureprivate.h"
+#include "gsk/ngl/fp16private.h"
 
 /**
  * GdkMemoryTexture:
@@ -62,6 +63,22 @@ gdk_memory_format_bytes_per_pixel (GdkMemoryFormat format)
     case GDK_MEMORY_B8G8R8:
       return 3;
 
+    case GDK_MEMORY_R16G16B16:
+      return 6;
+
+    case GDK_MEMORY_R16G16B16A16_PREMULTIPLIED:
+    case GDK_MEMORY_R16G16B16A16_FLOAT_PREMULTIPLIED:
+      return 8;
+
+    case GDK_MEMORY_R16G16B16_FLOAT:
+      return 6;
+
+    case GDK_MEMORY_R32G32B32_FLOAT:
+      return 12;
+
+    case GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED:
+      return 16;
+
     case GDK_MEMORY_N_FORMATS:
     default:
       g_assert_not_reached ();
@@ -97,6 +114,18 @@ gdk_memory_texture_download (GdkTexture         *texture,
                       area->width, area->height);
 }
 
+static GBytes *
+gdk_memory_texture_download_format (GdkTexture      *texture,
+                                    GdkMemoryFormat  format)
+{
+  GdkMemoryTexture *self = GDK_MEMORY_TEXTURE (texture);
+
+  if (self->format == format)
+    return g_bytes_ref (self->bytes);
+
+  return NULL;
+}
+
 static void
 gdk_memory_texture_class_init (GdkMemoryTextureClass *klass)
 {
@@ -104,6 +133,7 @@ gdk_memory_texture_class_init (GdkMemoryTextureClass *klass)
   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 
   texture_class->download = gdk_memory_texture_download;
+  texture_class->download_format = gdk_memory_texture_download_format;
   gobject_class->dispose = gdk_memory_texture_dispose;
 }
 
@@ -148,7 +178,7 @@ gdk_memory_texture_new (int              width,
   return GDK_TEXTURE (self);
 }
 
-GdkMemoryFormat 
+GdkMemoryFormat
 gdk_memory_texture_get_format (GdkMemoryTexture *self)
 {
   return self->format;
@@ -169,8 +199,10 @@ gdk_memory_texture_get_stride (GdkMemoryTexture *self)
 static void
 convert_memcpy (guchar       *dest_data,
                 gsize         dest_stride,
+                GdkMemoryFormat dest_format,
                 const guchar *src_data,
                 gsize         src_stride,
+                GdkMemoryFormat src_format,
                 gsize         width,
                 gsize         height)
 {
@@ -184,8 +216,10 @@ convert_memcpy (guchar       *dest_data,
 static void \
 convert_swizzle ## A ## R ## G ## B (guchar       *dest_data, \
                                      gsize         dest_stride, \
+                                     GdkMemoryFormat dest_format, \
                                      const guchar *src_data, \
                                      gsize         src_stride, \
+                                     GdkMemoryFormat src_format, \
                                      gsize         width, \
                                      gsize         height) \
 { \
@@ -215,8 +249,10 @@ SWIZZLE(1,2,3,0)
 static void \
 convert_swizzle_opaque_## A ## R ## G ## B (guchar       *dest_data, \
                                             gsize         dest_stride, \
+                                            GdkMemoryFormat dest_format, \
                                             const guchar *src_data, \
                                             gsize         src_stride, \
+                                            GdkMemoryFormat src_format, \
                                             gsize         width, \
                                             gsize         height) \
 { \
@@ -248,8 +284,10 @@ static void \
 convert_swizzle_premultiply_ ## A ## R ## G ## B ## _ ## A2 ## R2 ## G2 ## B2 \
                                     (guchar       *dest_data, \
                                      gsize         dest_stride, \
+                                     GdkMemoryFormat dest_format, \
                                      const guchar *src_data, \
                                      gsize         src_stride, \
+                                     GdkMemoryFormat src_format, \
                                      gsize         width, \
                                      gsize         height) \
 { \
@@ -283,24 +321,447 @@ SWIZZLE_PREMULTIPLY (3,0,1,2, 0,1,2,3)
 SWIZZLE_PREMULTIPLY (3,0,1,2, 3,0,1,2)
 SWIZZLE_PREMULTIPLY (3,0,1,2, 0,3,2,1)
 
+#define SWIZZLE_16TO8_OPAQUE(A,R,G,B) \
+static void \
+convert_16to8_swizzle_opaque_ ## A ## R ## G ## B (guchar       *dest_data, \
+                                                   gsize         dest_stride, \
+                                                   GdkMemoryFormat dest_format, \
+                                                   const guchar *src_data, \
+                                                   gsize         src_stride, \
+                                                   GdkMemoryFormat src_format, \
+                                                   gsize         width, \
+                                                   gsize         height) \
+{ \
+  gsize x, y; \
+\
+  for (y = 0; y < height; y++) \
+    { \
+      guint16 *src = (guint16 *)src_data; \
+      for (x = 0; x < width; x++) \
+        { \
+          dest_data[4 * x + A] = 255; \
+          dest_data[4 * x + R] = (guchar)(src[4 * x + 0] >> 8); \
+          dest_data[4 * x + G] = (guchar)(src[4 * x + 1] >> 8); \
+          dest_data[4 * x + B] = (guchar)(src[4 * x + 2] >> 8); \
+        } \
+\
+      dest_data += dest_stride; \
+      src_data += src_stride; \
+    } \
+}
+
+SWIZZLE_16TO8_OPAQUE(0,1,2,3)
+SWIZZLE_16TO8_OPAQUE(2,1,0,3)
+SWIZZLE_16TO8_OPAQUE(1,2,3,0)
+
+#define SWIZZLE_16TO8(A,R,G,B) \
+static void \
+convert_16to8_swizzle_ ## A ## R ## G ## B (guchar       *dest_data, \
+                                            gsize         dest_stride, \
+                                            GdkMemoryFormat dest_format, \
+                                            const guchar *src_data, \
+                                            gsize         src_stride, \
+                                            GdkMemoryFormat src_format, \
+                                            gsize         width, \
+                                            gsize         height) \
+{ \
+  gsize x, y; \
+\
+  for (y = 0; y < height; y++) \
+    { \
+      guint16 *src = (guint16 *)src_data; \
+      for (x = 0; x < width; x++) \
+        { \
+          dest_data[4 * x + A] = (guchar)(src[4 * x + 0] >> 8); \
+          dest_data[4 * x + R] = (guchar)(src[4 * x + 1] >> 8); \
+          dest_data[4 * x + G] = (guchar)(src[4 * x + 2] >> 8); \
+          dest_data[4 * x + B] = (guchar)(src[4 * x + 3] >> 8); \
+        } \
+\
+      dest_data += dest_stride; \
+      src_data += src_stride; \
+    } \
+}
+
+SWIZZLE_16TO8(0,1,2,3)
+SWIZZLE_16TO8(2,1,0,3)
+SWIZZLE_16TO8(1,2,3,0)
+
+#define SWIZZLE_FP16_OPAQUE(A,R,G,B) \
+static void \
+convert_fp16_swizzle_opaque_ ## A ## R ## G ## B (guchar       *dest_data, \
+                                                  gsize         dest_stride, \
+                                                  GdkMemoryFormat dest_format, \
+                                                  const guchar *src_data, \
+                                                  gsize         src_stride, \
+                                                  GdkMemoryFormat src_format, \
+                                                  gsize         width, \
+                                                  gsize         height) \
+{ \
+  gsize x, y; \
+  float *c; \
+\
+c = g_malloc (width * sizeof (float)); \
+  for (y = 0; y < height; y++) \
+    { \
+      guint16 *src = (guint16 *)src_data; \
+      half_to_float (src, c, width); \
+      for (x = 0; x < width; x++) \
+        { \
+          dest_data[4 * x + A] = 255; \
+          dest_data[4 * x + R] = (guchar)(255 * c[3 * x + 0]); \
+          dest_data[4 * x + G] = (guchar)(255 * c[3 * x + 1]); \
+          dest_data[4 * x + B] = (guchar)(255 * c[3 * x + 2]); \
+        } \
+      dest_data += dest_stride; \
+      src_data += src_stride; \
+    } \
+  g_free (c); \
+}
+
+SWIZZLE_FP16_OPAQUE(3,2,1,0)
+SWIZZLE_FP16_OPAQUE(0,1,2,3)
+SWIZZLE_FP16_OPAQUE(3,0,1,2)
+
+#define SWIZZLE_FP16(A,R,G,B) \
+static void \
+convert_fp16_swizzle_ ## A ## R ## G ## B (guchar       *dest_data, \
+                                           gsize         dest_stride, \
+                                           GdkMemoryFormat dest_format, \
+                                           const guchar *src_data, \
+                                           gsize         src_stride, \
+                                           GdkMemoryFormat src_format, \
+                                           gsize         width, \
+                                           gsize         height) \
+{ \
+  gsize x, y; \
+  float *c; \
+\
+  c = g_malloc (width * sizeof (float)); \
+  for (y = 0; y < height; y++) \
+    { \
+      guint16 *src = (guint16 *)src_data; \
+      half_to_float (src, c, width); \
+      for (x = 0; x < width; x++) \
+        { \
+          dest_data[4 * x + A] = (guchar)(255 * c[4 * x + 0]); \
+          dest_data[4 * x + R] = (guchar)(255 * c[4 * x + 1]); \
+          dest_data[4 * x + G] = (guchar)(255 * c[4 * x + 2]); \
+          dest_data[4 * x + B] = (guchar)(255 * c[4 * x + 3]); \
+        } \
+      dest_data += dest_stride; \
+      src_data += src_stride; \
+    } \
+  g_free (c); \
+}
+
+SWIZZLE_FP16(3,2,1,0)
+SWIZZLE_FP16(0,1,2,3)
+SWIZZLE_FP16(3,0,1,2)
+
+#define SWIZZLE_FLOAT_OPAQUE(A,R,G,B) \
+static void \
+convert_float_swizzle_opaque_ ## A ## R ## G ## B (guchar       *dest_data, \
+                                                   gsize         dest_stride, \
+                                                   GdkMemoryFormat dest_format, \
+                                                   const guchar *src_data, \
+                                                   gsize         src_stride, \
+                                                   GdkMemoryFormat src_format, \
+                                                   gsize         width, \
+                                                   gsize         height) \
+{ \
+  gsize x, y; \
+\
+  for (y = 0; y < height; y++) \
+    { \
+      float *src = (float *)src_data; \
+      for (x = 0; x < width; x++) \
+        { \
+          dest_data[4 * x + A] = 255; \
+          dest_data[4 * x + R] = (guchar)(255 * src[3 * x + 0]); \
+          dest_data[4 * x + G] = (guchar)(255 * src[3 * x + 1]); \
+          dest_data[4 * x + B] = (guchar)(255 * src[3 * x + 2]); \
+        } \
+\
+      dest_data += dest_stride; \
+      src_data += src_stride; \
+    } \
+}
+
+SWIZZLE_FLOAT_OPAQUE(3,2,1,0)
+SWIZZLE_FLOAT_OPAQUE(0,1,2,3)
+SWIZZLE_FLOAT_OPAQUE(3,0,1,2)
+
+#define SWIZZLE_FLOAT(A,R,G,B) \
+static void \
+convert_float_swizzle_ ## A ## R ## G ## B (guchar       *dest_data, \
+                                            gsize         dest_stride, \
+                                            GdkMemoryFormat dest_format, \
+                                            const guchar *src_data, \
+                                            gsize         src_stride, \
+                                            GdkMemoryFormat src_format, \
+                                            gsize         width, \
+                                            gsize         height) \
+{ \
+  gsize x, y; \
+\
+  for (y = 0; y < height; y++) \
+    { \
+      float *src = (float *)src_data; \
+      for (x = 0; x < width; x++) \
+        { \
+          dest_data[4 * x + A] = (guchar)(255 * src[3 * x + 0]); \
+          dest_data[4 * x + R] = (guchar)(255 * src[3 * x + 1]); \
+          dest_data[4 * x + G] = (guchar)(255 * src[3 * x + 2]); \
+          dest_data[4 * x + B] = (guchar)(255 * src[3 * x + 3]); \
+        } \
+\
+      dest_data += dest_stride; \
+      src_data += src_stride; \
+    } \
+}
+
+SWIZZLE_FLOAT(3,2,1,0)
+SWIZZLE_FLOAT(0,1,2,3)
+SWIZZLE_FLOAT(3,0,1,2)
+
 typedef void (* ConversionFunc) (guchar       *dest_data,
                                  gsize         dest_stride,
+                                 GdkMemoryFormat  dest_format,
                                  const guchar *src_data,
                                  gsize         src_stride,
+                                 GdkMemoryFormat  src_format,
                                  gsize         width,
                                  gsize         height);
 
-static ConversionFunc converters[GDK_MEMORY_N_FORMATS][3] =
+static ConversionFunc converters_to_bgra[GDK_MEMORY_N_FORMATS] =
 {
-  { convert_memcpy, convert_swizzle3210, convert_swizzle2103 },
-  { convert_swizzle3210, convert_memcpy, convert_swizzle3012 },
-  { convert_swizzle2103, convert_swizzle1230, convert_memcpy },
-  { convert_swizzle_premultiply_3210_3210, convert_swizzle_premultiply_0123_3210, convert_swizzle_premultiply_3012_3210,  },
-  { convert_swizzle_premultiply_3210_0123, convert_swizzle_premultiply_0123_0123, convert_swizzle_premultiply_3012_0123 },
-  { convert_swizzle_premultiply_3210_3012, convert_swizzle_premultiply_0123_3012, convert_swizzle_premultiply_3012_3012 },
-  { convert_swizzle_premultiply_3210_0321, convert_swizzle_premultiply_0123_0321, convert_swizzle_premultiply_3012_0321 },
-  { convert_swizzle_opaque_3210, convert_swizzle_opaque_0123, convert_swizzle_opaque_3012 },
-  { convert_swizzle_opaque_3012, convert_swizzle_opaque_0321, convert_swizzle_opaque_3210 }
+  convert_memcpy,
+  convert_swizzle3210,
+  convert_swizzle2103,
+  convert_swizzle_premultiply_3210_3210,
+  convert_swizzle_premultiply_3210_0123,
+  convert_swizzle_premultiply_3210_3012,
+  convert_swizzle_premultiply_3210_0321,
+  convert_swizzle_opaque_3210,
+  convert_swizzle_opaque_3012,
+  convert_16to8_swizzle_opaque_2103,
+  convert_16to8_swizzle_2103,
+  convert_fp16_swizzle_opaque_3210,
+  convert_fp16_swizzle_3210,
+  convert_float_swizzle_opaque_3210,
+  convert_float_swizzle_3210,
+};
+
+static ConversionFunc converters_to_argb[GDK_MEMORY_N_FORMATS] =
+{
+  convert_swizzle3210,
+  convert_memcpy,
+  convert_swizzle1230,
+  convert_swizzle_premultiply_0123_3210,
+  convert_swizzle_premultiply_0123_0123,
+  convert_swizzle_premultiply_0123_3012,
+  convert_swizzle_premultiply_0123_0321,
+  convert_swizzle_opaque_0123,
+  convert_swizzle_opaque_0321,
+  convert_16to8_swizzle_opaque_1230,
+  convert_16to8_swizzle_1230,
+  convert_fp16_swizzle_opaque_0123,
+  convert_fp16_swizzle_0123,
+  convert_float_swizzle_opaque_0123,
+  convert_float_swizzle_0123,
+};
+
+static ConversionFunc converters_to_rgba[GDK_MEMORY_N_FORMATS] =
+{
+  convert_swizzle2103,
+  convert_swizzle3012,
+  convert_memcpy,
+  convert_swizzle_premultiply_3012_3210,
+  convert_swizzle_premultiply_3012_0123,
+  convert_swizzle_premultiply_3012_3012,
+  convert_swizzle_premultiply_3012_0321,
+  convert_swizzle_opaque_3012,
+  convert_swizzle_opaque_3210,
+  convert_16to8_swizzle_opaque_0123,
+  convert_16to8_swizzle_0123,
+  convert_fp16_swizzle_opaque_3012,
+  convert_fp16_swizzle_3012,
+  convert_float_swizzle_opaque_3012,
+  convert_float_swizzle_3012
+};
+
+static void
+convert_rgba_to_hdr (guchar       *dest_data,
+                     gsize         dest_stride,
+                     GdkMemoryFormat  dest_format,
+                     const guchar *src_data,
+                     gsize         src_stride,
+                     GdkMemoryFormat  src_format,
+                     gsize         width,
+                     gsize         height)
+{
+  gsize x, y;
+
+  for (y = 0; y < height; y++)
+    {
+      guint16 *src = (guint16 *)src_data;
+      float *dest = (float *)dest_data;
+      for (x = 0; x < width; x++)
+        {
+          dest[4 * (y * width + x) + 0] = src[3 * (y * width + x) + 0] / 255.f;
+          dest[4 * (y * width + x) + 1] = src[3 * (y * width + x) + 1] / 255.f;
+          dest[4 * (y * width + x) + 2] = src[3 * (y * width + x) + 2] / 255.f;
+          dest[4 * (y * width + x) + 3] = src[3 * (y * width + x) + 3] / 255.f;
+        }
+      dest_data += dest_stride;
+      src_data += src_stride;
+    }
+}
+
+static void
+convert_8bit_to_hdr (guchar       *dest_data,
+                     gsize         dest_stride,
+                     GdkMemoryFormat  dest_format,
+                     const guchar *src_data,
+                     gsize         src_stride,
+                     GdkMemoryFormat  src_format,
+                     gsize         width,
+                     gsize         height)
+{
+  guchar *data;
+
+  /* TODO: this could perhaps be done in-place */
+  data = g_malloc (width * height * 4);
+
+  gdk_memory_convert (data, 4 * width, GDK_MEMORY_R8G8B8A8_PREMULTIPLIED,
+                      src_data, src_stride, src_format,
+                      width, height);
+  convert_rgba_to_hdr (dest_data, dest_stride, dest_format,
+                       data, 4 * width, GDK_MEMORY_R8G8B8A8_PREMULTIPLIED,
+                       width, height);
+
+  g_free (data);
+}
+
+static void
+convert_16bit_to_hdr (guchar       *dest_data,
+                      gsize         dest_stride,
+                      GdkMemoryFormat  dest_format,
+                      const guchar *src_data,
+                      gsize         src_stride,
+                      GdkMemoryFormat  src_format,
+                      gsize         width,
+                      gsize         height)
+{
+  gsize x, y;
+
+  for (y = 0; y < height; y++)
+    {
+      guint16 *src = (guint16 *)src_data;
+      float *dest = (float *)dest_data;
+      for (x = 0; x < width; x++)
+        {
+          dest[4 * (y * width + x) + 0] = src[3 * (y * width + x) + 0] / 65535.f;
+          dest[4 * (y * width + x) + 1] = src[3 * (y * width + x) + 1] / 65535.f;
+          dest[4 * (y * width + x) + 2] = src[3 * (y * width + x) + 2] / 65535.f;
+          dest[4 * (y * width + x) + 3] = src[3 * (y * width + x) + 3] / 65535.f;
+        }
+      dest_data += dest_stride;
+      src_data += src_stride;
+    }
+}
+
+static void
+convert_fp16_to_hdr (guchar       *dest_data,
+                     gsize         dest_stride,
+                     GdkMemoryFormat  dest_format,
+                     const guchar *src_data,
+                     gsize         src_stride,
+                     GdkMemoryFormat  src_format,
+                     gsize         width,
+                     gsize         height)
+{
+  gsize x, y;
+  int src_bpp;
+
+  if (src_format == GDK_MEMORY_R16G16B16A16_FLOAT_PREMULTIPLIED)
+    src_bpp = 4;
+  else
+    src_bpp = 3;
+
+  for (y = 0; y < height; y++)
+    {
+      guint16 *src = (guint16 *)src_data;
+      float *dest = (float *)dest_data;
+      for (x = 0; x < width; x++)
+        {
+          guint16 h[4];
+
+          h[0] = src[src_bpp * (y * width + x)];
+          h[1] = src[src_bpp * (y * width + x) + 1];
+          h[2] = src[src_bpp * (y * width + x) + 2];
+          if (src_bpp == 4)
+            h[3] = src[src_bpp * (y * width + x) + 3];
+          else
+            h[3] = FP16_ONE;
+          half_to_float4 (h, &dest[4 * (y * width + x)]);
+        }
+      dest_data += dest_stride;
+      src_data += src_stride;
+    }
+}
+
+static void
+convert_float_to_hdr (guchar       *dest_data,
+                      gsize         dest_stride,
+                      GdkMemoryFormat  dest_format,
+                      const guchar *src_data,
+                      gsize         src_stride,
+                      GdkMemoryFormat  src_format,
+                      gsize         width,
+                      gsize         height)
+{
+  gsize x, y;
+
+  for (y = 0; y < height; y++)
+    {
+      float *src = (float *)src_data;
+      float *dest = (float *)dest_data;
+      for (x = 0; x < width; x++)
+        {
+          dest[4 * (y * width + x) + 0] = src[3 * (y * width + x) + 0];
+          dest[4 * (y * width + x) + 1] = src[3 * (y * width + x) + 1];
+          dest[4 * (y * width + x) + 2] = src[3 * (y * width + x) + 2];
+          dest[4 * (y * width + x) + 3] = 1.0;
+        }
+      dest_data += dest_stride;
+      src_data += src_stride;
+    }
+}
+
+static ConversionFunc converters_to_hdr[GDK_MEMORY_N_FORMATS] =
+{
+  convert_8bit_to_hdr,
+  convert_8bit_to_hdr,
+  convert_rgba_to_hdr,
+  convert_8bit_to_hdr,
+  convert_8bit_to_hdr,
+  convert_8bit_to_hdr,
+  convert_8bit_to_hdr,
+  convert_8bit_to_hdr,
+  convert_8bit_to_hdr,
+  convert_16bit_to_hdr,
+  convert_fp16_to_hdr,
+  convert_fp16_to_hdr,
+  convert_float_to_hdr,
+  convert_memcpy
+};
+static ConversionFunc* converters[GDK_MEMORY_N_FORMATS] = {
+  converters_to_bgra, converters_to_argb, converters_to_rgba,
+  NULL, NULL, NULL, NULL, NULL, NULL,
+  NULL, NULL, NULL, NULL,
+  converters_to_hdr
 };
 
 void
@@ -316,5 +777,7 @@ gdk_memory_convert (guchar          *dest_data,
   g_assert (dest_format < 3);
   g_assert (src_format < GDK_MEMORY_N_FORMATS);
 
-  converters[src_format][dest_format] (dest_data, dest_stride, src_data, src_stride, width, height);
+  converters[dest_format][src_format] (dest_data, dest_stride, dest_format,
+                                       src_data, src_stride, src_format,
+                                       width, height);
 }

gdk/gdkmemorytexture.h

@@ -42,6 +42,20 @@ G_BEGIN_DECLS
  * @GDK_MEMORY_A8B8G8R8: 4 bytes; for alpha, blue, green, red.
  * @GDK_MEMORY_R8G8B8: 3 bytes; for red, green, blue. The data is opaque.
  * @GDK_MEMORY_B8G8R8: 3 bytes; for blue, green, red. The data is opaque.
+ * @GDK_MEMORY_R16G16B16: 3 guint16 values; for red, green, blue. Since 4.6
+ * @GDK_MEMORY_R16G16B16A16_PREMULTIPLIED: 4 guint16 values; for red, green,
+ *   blue, alpha. The color values are premultiplied with the alpha value.
+ *   Since 4.6
+ * @GDK_MEMORY_R16G16B16_FLOAT: 3 half-float values; for red, green, blue.
+ *   The data is opaque. Since 4.6
+ * @GDK_MEMORY_R16G16B16A16_FLOAT_PREMULTIPLIED: 4 half-float values; for
+ *   red, green, blue and alpha. The color values are premultiplied with
+ *   the alpha value. Since 4.6
+ * @GDK_MEMORY_B32G32R32_FLOAT: 3 float values; for blue, green, red.
+ *   The data is opaque. Since 4.6
+ * @GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED: 4 float values; for
+ *   red, green, blue and alpha. The color values are premultiplied with
+ *   the alpha value. Since 4.6
  * @GDK_MEMORY_N_FORMATS: The number of formats. This value will change as
  *   more formats get added, so do not rely on its concrete integer.
  *
@@ -53,6 +67,8 @@ G_BEGIN_DECLS
  * CAIRO_FORMAT_ARGB32 is represented by different `GdkMemoryFormats`
  * on architectures with different endiannesses.
  *
+ * Note that color data is assumed to be linear.
+ *
  * Its naming is modelled after
  * [VkFormat](https://www.khronos.org/registry/vulkan/specs/1.0/html/vkspec.html#VkFormat)
  * for details).
@@ -67,6 +83,12 @@ typedef enum {
   GDK_MEMORY_A8B8G8R8,
   GDK_MEMORY_R8G8B8,
   GDK_MEMORY_B8G8R8,
+  GDK_MEMORY_R16G16B16,
+  GDK_MEMORY_R16G16B16A16_PREMULTIPLIED,
+  GDK_MEMORY_R16G16B16_FLOAT,
+  GDK_MEMORY_R16G16B16A16_FLOAT_PREMULTIPLIED,
+  GDK_MEMORY_R32G32B32_FLOAT,
+  GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED,
 
   GDK_MEMORY_N_FORMATS
 } GdkMemoryFormat;

gdk/gdkpng.c

@@ -0,0 +1,489 @@
+/* GDK - The GIMP Drawing Kit
+ * Copyright (C) 2021 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "gdkpng.h"
+
+#include "gdktexture.h"
+#include "gdkmemorytextureprivate.h"
+#include "gsk/ngl/fp16private.h"
+#include <png.h>
+#include <stdio.h>
+
+/* {{{ IO handling */
+
+#ifdef HAVE_FOPENCOOKIE
+
+static ssize_t
+read_stream (void   *cookie,
+             char   *buf,
+             size_t  size)
+{
+  GInputStream *stream = cookie;
+
+  return g_input_stream_read (stream, buf, size, NULL, NULL);
+}
+
+static ssize_t
+write_stream (void       *cookie,
+              const char *buf,
+              size_t      size)
+{
+  GOutputStream *stream = cookie;
+
+  return g_output_stream_write (stream, buf, size, NULL, NULL);
+}
+
+static int
+seek_stream (void    *cookie,
+             off64_t *offset,
+             int      whence)
+{
+  GSeekable *seekable = cookie;
+  GSeekType seek_type;
+
+  if (whence == SEEK_SET)
+    seek_type = G_SEEK_SET;
+  else if (whence == SEEK_CUR)
+    seek_type = G_SEEK_CUR;
+  else if (whence == SEEK_END)
+    seek_type = G_SEEK_END;
+  else
+    g_assert_not_reached ();
+
+  if (g_seekable_seek (seekable, *offset, seek_type, NULL, NULL))
+    {
+      *offset = g_seekable_tell (seekable);
+      return 0;
+    }
+
+  return -1;
+}
+
+static int
+close_stream (void *cookie)
+{
+  GObject *stream = cookie;
+
+  g_object_unref (stream);
+
+  return 0;
+}
+
+static cookie_io_functions_t cookie_funcs = {
+  read_stream,
+  write_stream,
+  seek_stream,
+  close_stream
+};
+
+#else
+
+static GBytes *
+read_all_data (GInputStream  *source,
+               GError       **error)
+{
+  GOutputStream *output;
+  gssize size;
+  GBytes *bytes;
+
+  output = g_memory_output_stream_new (NULL, 0, g_realloc, g_free);
+  size = g_output_stream_splice (output, source, 0, NULL, error);
+  if (size == -1)
+    {
+      g_object_unref (output);
+      return NULL;
+    }
+
+  g_output_stream_close (output, NULL, NULL);
+  bytes = g_memory_output_stream_steal_as_bytes (G_MEMORY_OUTPUT_STREAM (output));
+  g_object_unref (output);
+
+  return bytes;
+}
+
+#endif
+
+/* }}} */
+/* {{{ Format conversion */
+
+static void
+convert_half_float (guchar            *dest_data,
+                    gsize              dest_stride,
+                    GdkMemoryFormat    dest_format,
+                    const guchar      *src_data,
+                    gsize              src_stride,
+                    GdkMemoryFormat    src_format,
+                    gsize              width,
+                    gsize              height)
+{
+  gsize x, y;
+  guint16 *dest;
+  const guint16 *src;
+  float *c;
+
+  c = g_malloc (width * 4 * sizeof (float));
+  for (y = 0; y < height; y++)
+    {
+      dest = (guint16 *)dest_data;
+      src = (const guint16 *)src_data;
+
+      half_to_float (src, c, width);
+      for (x = 0; x < width; x++)
+        {
+          dest[4 * x    ] = (guint16)(65535 * c[4 * x    ]);
+          dest[4 * x + 1] = (guint16)(65535 * c[4 * x + 1]);
+          dest[4 * x + 2] = (guint16)(65535 * c[4 * x + 2]);
+          if (src_format == GDK_MEMORY_R16G16B16A16_FLOAT_PREMULTIPLIED)
+            dest[4 * x + 3] = (guint16)(65535 * c[4 * x + 3]);
+          else
+            dest[4 * x + 3] = 65535;
+        }
+      dest_data += dest_stride;
+      src_data += src_stride;
+    }
+  g_free (c);
+}
+
+static void
+convert_float (guchar            *dest_data,
+               gsize              dest_stride,
+               GdkMemoryFormat    dest_format,
+               const guchar      *src_data,
+               gsize              src_stride,
+               GdkMemoryFormat    src_format,
+               gsize              width,
+               gsize              height)
+{
+  gsize x, y;
+  guint16 *dest;
+  const float *src;
+
+  for (y = 0; y < height; y++)
+    {
+      dest = (guint16 *)dest_data;
+      src = (const float *)src_data;
+      for (x = 0; x < width; x++)
+        {
+          dest[4 * x    ] = (guint16)(65535 * src[4 * x    ]);
+          dest[4 * x + 1] = (guint16)(65535 * src[4 * x + 1]);
+          dest[4 * x + 2] = (guint16)(65535 * src[4 * x + 2]);
+          if (src_format == GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED)
+            dest[4 * x + 3] = (guint16)(65535 * src[4 * x + 3]);
+          else
+            dest[4 * x + 3] = 65535;
+        }
+      dest_data += dest_stride;
+      src_data += src_stride;
+    }
+}
+
+static void
+convert (guchar            *dest_data,
+         gsize              dest_stride,
+         GdkMemoryFormat    dest_format,
+         const guchar      *src_data,
+         gsize              src_stride,
+         GdkMemoryFormat    src_format,
+         gsize              width,
+         gsize              height)
+{
+  if (dest_format < 3)
+    gdk_memory_convert (dest_data, dest_stride, dest_format,
+                        src_data, src_stride, src_format,
+                        width, height);
+  else
+    {
+      g_assert (dest_format == GDK_MEMORY_R16G16B16A16_PREMULTIPLIED);
+
+      switch ((int)src_format)
+        {
+        case GDK_MEMORY_R16G16B16_FLOAT:
+        case GDK_MEMORY_R16G16B16A16_FLOAT_PREMULTIPLIED:
+          convert_half_float (dest_data, dest_stride, dest_format,
+                              src_data, src_stride, src_format,
+                              width, height);
+          break;
+        case GDK_MEMORY_R32G32B32_FLOAT:
+        case GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED:
+          convert_float (dest_data, dest_stride, dest_format,
+                         src_data, src_stride, src_format,
+                         width, height);
+          break;
+        default:
+          g_assert_not_reached ();
+        }
+    }
+}
+
+/* }}} */
+/* {{{ Public API */
+
+GdkTexture *
+gdk_load_png (GInputStream  *stream,
+              GError       **error)
+{
+  png_image image = { NULL, PNG_IMAGE_VERSION, 0, };
+  gsize size;
+  gsize stride;
+  guint16 *buffer;
+  GBytes *bytes;
+  GdkTexture *texture;
+
+#ifdef HAVE_FOPENCOOKIE
+  FILE *file = fopencookie (g_object_ref (stream), "r", cookie_funcs);
+
+  png_image_begin_read_from_stdio (&image, file);
+#else
+  GBytes *data;
+
+  data = read_all_data (stream, error);
+  if (!data)
+    return NULL;
+  png_image_begin_read_from_memory (&image,
+                                    g_bytes_get_data (data, NULL),
+                                    g_bytes_get_size (data));
+#endif
+
+  image.format = PNG_FORMAT_LINEAR_RGB_ALPHA;
+
+  stride = PNG_IMAGE_ROW_STRIDE (image);
+  size = PNG_IMAGE_BUFFER_SIZE (image, stride);
+  buffer = g_malloc (size);
+
+  png_image_finish_read (&image, NULL, buffer, stride, NULL);
+
+#ifdef HAVE_FOPENCOOKIE
+  fclose (file);
+#else
+  g_bytes_unref (data);
+#endif
+
+  bytes = g_bytes_new_take (buffer, size);
+
+  texture = gdk_memory_texture_new (image.width, image.height,
+                                    GDK_MEMORY_R16G16B16A16_PREMULTIPLIED,
+                                    bytes, 2 * stride);
+
+  g_bytes_unref (bytes);
+
+  png_image_free (&image);
+
+  return texture;
+}
+
+gboolean
+gdk_save_png (GOutputStream    *stream,
+              const guchar     *data,
+              int               width,
+              int               height,
+              int               stride,
+              GdkMemoryFormat   format,
+              GError          **error)
+{
+  png_image image = { NULL, PNG_IMAGE_VERSION, 0, };
+  gboolean result;
+  guchar *new_data = NULL;
+
+  switch ((int)format)
+    {
+    case GDK_MEMORY_R8G8B8A8_PREMULTIPLIED:
+      image.format = PNG_FORMAT_RGBA;
+      break;
+    case GDK_MEMORY_B8G8R8A8_PREMULTIPLIED:
+    case GDK_MEMORY_A8R8G8B8_PREMULTIPLIED:
+    case GDK_MEMORY_B8G8R8A8:
+    case GDK_MEMORY_A8R8G8B8:
+    case GDK_MEMORY_R8G8B8A8:
+    case GDK_MEMORY_A8B8G8R8:
+    case GDK_MEMORY_R8G8B8:
+    case GDK_MEMORY_B8G8R8:
+      stride = width * 4;
+      new_data = g_malloc (stride * height);
+      convert (new_data, stride, GDK_MEMORY_R8G8B8A8_PREMULTIPLIED,
+               data, width * gdk_memory_format_bytes_per_pixel (format), format,
+               width, height);
+      data = new_data;
+      image.format = PNG_FORMAT_RGBA;
+      break;
+    case GDK_MEMORY_R16G16B16A16_PREMULTIPLIED:
+      image.format = PNG_FORMAT_LINEAR_RGB_ALPHA;
+      break;
+    case GDK_MEMORY_R16G16B16:
+      image.format = PNG_FORMAT_LINEAR_RGB;
+      break;
+    case GDK_MEMORY_R16G16B16_FLOAT:
+    case GDK_MEMORY_R16G16B16A16_FLOAT_PREMULTIPLIED:
+    case GDK_MEMORY_R32G32B32_FLOAT:
+    case GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED:
+      stride = width * 8;
+      new_data = g_malloc (stride * height);
+      convert (new_data, stride, GDK_MEMORY_R16G16B16A16_PREMULTIPLIED,
+               data, width * gdk_memory_format_bytes_per_pixel (format), format,
+               width, height);
+      image.format = PNG_FORMAT_LINEAR_RGB_ALPHA;
+      break;
+      break;
+    default:
+      g_assert_not_reached ();
+    }
+
+  if (image.format & PNG_FORMAT_FLAG_LINEAR)
+    stride /= 2;
+
+#ifdef HAVE_FOPENCOOKIE
+  FILE *file = fopencookie (g_object_ref (stream), "w", cookie_funcs);
+  result = png_image_write_to_stdio (&image, file, FALSE, data, stride, NULL);
+  fclose (file);
+#else
+  gsize written;
+  png_alloc_size_t size;
+  gpointer buffer;
+  png_image_write_get_memory_size (image, size, FALSE, data, stride, NULL);
+  buffer = g_malloc (size);
+  result = png_image_write_to_memory (&image, buffer, &size, FALSE, data, stride, NULL);
+  if (result)
+    result = g_output_stream_write_all (stream, buffer, (gsize)size, &written, NULL, NULL);
+  g_free (buffer);
+#endif
+
+  if (!result)
+    {
+      g_set_error_literal (error,
+                           G_IO_ERROR, G_IO_ERROR_FAILED,
+                           "Saving png failed");
+    }
+
+  png_image_free (&image);
+
+  g_free (new_data);
+
+  return result;
+}
+
+/* }}} */
+/* {{{ Async code */
+
+static void
+load_png_in_thread (GTask        *task,
+                    gpointer      source_object,
+                    gpointer      task_data,
+                    GCancellable *cancellable)
+{
+  GInputStream *stream = source_object;
+  GdkTexture *texture;
+  GError *error = NULL;
+
+  texture = gdk_load_png (stream, &error);
+
+  if (texture)
+    g_task_return_pointer (task, texture, g_object_unref);
+  else
+    g_task_return_error (task, error);
+}
+
+void
+gdk_load_png_async (GInputStream         *stream,
+                    GCancellable         *cancellable,
+                    GAsyncReadyCallback   callback,
+                    gpointer              user_data)
+{
+  GTask *task;
+
+  task = g_task_new (stream, cancellable, callback, user_data);
+  g_task_run_in_thread (task, load_png_in_thread);
+  g_object_unref (task);
+}
+
+GdkTexture *
+gdk_load_png_finish (GAsyncResult  *result,
+                     GError       **error)
+{
+  return g_task_propagate_pointer (G_TASK (result), error);
+}
+
+typedef struct {
+  const guchar *data;
+  int width;
+  int height;
+  int stride;
+  GdkMemoryFormat format;
+} SavePngData;
+
+static void
+save_png_in_thread (GTask        *task,
+                    gpointer      source_object,
+                    gpointer      task_data,
+                    GCancellable *cancellable)
+{
+  GOutputStream *stream = source_object;
+  SavePngData *data = task_data;
+  GError *error = NULL;
+  gboolean result;
+
+  result = gdk_save_png (stream,
+                         data->data,
+                         data->width,
+                         data->height,
+                         data->stride,
+                         data->format,
+                         &error);
+
+  if (result)
+    g_task_return_boolean (task, result);
+  else
+    g_task_return_error (task, error);
+}
+
+void
+gdk_save_png_async (GOutputStream          *stream,
+                    const guchar           *data,
+                    int                     width,
+                    int                     height,
+                    int                     stride,
+                    GdkMemoryFormat         format,
+                    GCancellable           *cancellable,
+                    GAsyncReadyCallback     callback,
+                    gpointer                user_data)
+{
+  GTask *task;
+  SavePngData *save_data;
+
+  save_data = g_new0 (SavePngData, 1);
+  save_data->data = data;
+  save_data->width = width;
+  save_data->height = height;
+  save_data->stride = stride;
+  save_data->format = format;
+
+  task = g_task_new (stream, cancellable, callback, user_data);
+  g_task_set_task_data (task, save_data, g_free);
+  g_task_run_in_thread (task, save_png_in_thread);
+  g_object_unref (task);
+}
+
+gboolean
+gdk_save_png_finish (GAsyncResult  *result,
+                     GError       **error)
+{
+  return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+/* }}} */
+
+/* vim:set foldmethod=marker expandtab: */

gdk/gdkpng.h

@@ -0,0 +1,56 @@
+/* GDK - The GIMP Drawing Kit
+ * Copyright (C) 2021 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GDK_PNG_H__
+#define __GDK_PNG_H__
+
+#include "gdkmemorytexture.h"
+#include <gio/gio.h>
+
+GdkTexture *gdk_load_png        (GInputStream           *stream,
+                                 GError                **error);
+
+void        gdk_load_png_async  (GInputStream           *stream,
+                                 GCancellable           *cancellable,
+                                 GAsyncReadyCallback     callback,
+                                 gpointer                user_data);
+
+GdkTexture *gdk_load_png_finish (GAsyncResult           *result,
+                                 GError                **error);
+
+gboolean    gdk_save_png        (GOutputStream          *stream,
+                                 const guchar           *data,
+                                 int                     width,
+                                 int                     height,
+                                 int                     stride,
+                                 GdkMemoryFormat         format,
+                                 GError                **error);
+
+void        gdk_save_png_async  (GOutputStream          *stream,
+                                 const guchar           *data,
+                                 int                     width,
+                                 int                     height,
+                                 int                     stride,
+                                 GdkMemoryFormat         format,
+                                 GCancellable           *cancellable,
+                                 GAsyncReadyCallback     callback,
+                                 gpointer                user_data);
+
+gboolean    gdk_save_png_finish (GAsyncResult           *result,
+                                 GError                **error);
+
+#endif

gdk/gdktexture.c

@@ -46,6 +46,9 @@
 #include "gdksnapshot.h"
 
 #include <graphene.h>
+#include "gdkpng.h"
+#include "gdktiff.h"
+#include "gdkjpeg.h"
 
 /* HACK: So we don't need to include any (not-yet-created) GSK or GTK headers */
 void
@@ -124,6 +127,13 @@ gdk_texture_real_download (GdkTexture         *self,
   GDK_TEXTURE_WARN_NOT_IMPLEMENTED_METHOD (self, download);
 }
 
+static GBytes *
+gdk_texture_real_download_format (GdkTexture      *self,
+                                  GdkMemoryFormat  format)
+{
+  return NULL;
+}
+
 static void
 gdk_texture_set_property (GObject      *gobject,
                           guint         prop_id,
@@ -188,6 +198,7 @@ gdk_texture_class_init (GdkTextureClass *klass)
   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 
   klass->download = gdk_texture_real_download;
+  klass->download_format = gdk_texture_real_download_format;
 
   gobject_class->set_property = gdk_texture_set_property;
   gobject_class->get_property = gdk_texture_get_property;
@@ -351,6 +362,10 @@ gdk_texture_new_from_resource (const char *resource_path)
  * The file format is detected automatically. The supported formats
  * are PNG and JPEG, though more formats might be available.
  *
+ * For PNG files, this function supports conversion from SRGB to
+ * linear data (including gamma correction) and can load 16bit
+ * data.
+ *
  * If %NULL is returned, then @error will be set.
  *
  * Return value: A newly-created `GdkTexture`
@@ -362,6 +377,9 @@ gdk_texture_new_from_file (GFile   *file,
   GdkTexture *texture;
   GdkPixbuf *pixbuf;
   GInputStream *stream;
+  GInputStream *buffered;
+  const void *data;
+  gsize size;
 
   g_return_val_if_fail (G_IS_FILE (file), NULL);
   g_return_val_if_fail (error == NULL || *error == NULL, NULL);
@@ -370,6 +388,35 @@ gdk_texture_new_from_file (GFile   *file,
   if (stream == NULL)
     return NULL;
 
+  buffered = g_buffered_input_stream_new (stream);
+  g_object_unref (stream);
+  stream = buffered;
+
+  g_buffered_input_stream_fill (G_BUFFERED_INPUT_STREAM (stream), 8, NULL, NULL);
+  data = g_buffered_input_stream_peek_buffer (G_BUFFERED_INPUT_STREAM (stream), &size);
+
+  if (memcmp (data, "\x89PNG", 4) == 0)
+    {
+      texture = gdk_load_png (stream, error);
+      g_object_unref (stream);
+      return texture;
+    }
+
+  if (memcmp (data, "MM\x00\x2a", 4) == 0 ||
+      memcmp (data, "II\x2a\x00", 4) == 0)
+    {
+      texture = gdk_load_tiff (stream, error);
+      g_object_unref (stream);
+      return texture;
+    }
+
+  if (memcmp (data, "\xff\xd8", 2) == 0)
+    {
+      texture = gdk_load_jpeg (stream, error);
+      g_object_unref (stream);
+      return texture;
+    }
+
   pixbuf = gdk_pixbuf_new_from_stream (stream, NULL, error);
   g_object_unref (stream);
   if (pixbuf == NULL)
@@ -491,6 +538,95 @@ gdk_texture_download (GdkTexture *texture,
                              stride);
 }
 
+/* Returns the texture data in the requested format if that
+ * can be done without conversion. NULL, otherwise.
+ */
+GBytes *
+gdk_texture_download_format (GdkTexture      *texture,
+                             GdkMemoryFormat  format)
+{
+  return GDK_TEXTURE_GET_CLASS (texture)->download_format (texture, format);
+}
+
+/* Returns the texture data in the requested format, converting
+ * it if necessary. This will only return NULL if we don't know
+ * how to convert from the texture's format to the requested one.
+ */
+GBytes *
+gdk_texture_convert_format (GdkTexture      *texture,
+                            GdkMemoryFormat  format)
+{
+  GdkMemoryFormat src_format;
+  GBytes *bytes;
+  int width, height, stride;
+  guchar *data;
+
+  for (int i = 0; i < GDK_MEMORY_N_FORMATS; i++)
+    {
+      bytes = gdk_texture_download_format (texture, i);
+      if (bytes)
+        {
+          src_format = i;
+          break;
+        }
+    }
+
+  if (!bytes || src_format == format)
+    return bytes;
+
+  /* convert from src_format to format */
+
+  width = gdk_texture_get_width (texture);
+  height = gdk_texture_get_height (texture);
+  stride = width * gdk_memory_format_bytes_per_pixel (format);
+  data = g_malloc (height * stride);
+
+  gdk_memory_convert (data, stride, format,
+                      g_bytes_get_data (bytes, NULL),
+                      g_bytes_get_size (bytes) / height,
+                      src_format,
+                      width, height);
+
+  g_bytes_unref (bytes);
+
+  return g_bytes_new_take (data, height * stride);
+}
+
+/*
+ * gdk_texture_download_float:
+ * @texture: a `GdkTexture`
+ * @data: (array): pointer to enough memory to be filled with the
+ *   downloaded data of @texture
+ *
+ * Downloads the @texture into local memory.
+ *
+ * This may be an expensive operation, as the actual texture data
+ * may reside on a GPU or on a remote display server.
+ *
+ * The data format of the downloaded data is equivalent to
+ * GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED, so every downloaded
+ * pixel requires 16 bytes of memory.
+ *
+ * Note that the caller is responsible to provide sufficiently
+ * aligned memory to access the resulting data directly as floats.
+ *
+ * Since: 4.6
+ */
+void
+gdk_texture_download_float (GdkTexture *texture,
+                            float      *data)
+{
+  GBytes *bytes;
+
+  bytes = gdk_texture_convert_format (texture, GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED);
+
+  g_assert (bytes);
+
+  memcpy (data, g_bytes_get_data (bytes, NULL), g_bytes_get_size (bytes));
+
+  g_bytes_unref (bytes);
+}
+
 gboolean
 gdk_texture_set_render_data (GdkTexture     *self,
                              gpointer        key,
@@ -537,6 +673,9 @@ gdk_texture_get_render_data (GdkTexture  *self,
  *
  * Store the given @texture to the @filename as a PNG file.
  *
+ * If the texture contains 16bit data, the generated PNG file
+ * will have linear 16bit data, otherwise it will contain SRGB.
+ *
  * This is a utility function intended for debugging and testing.
  * If you want more control over formats, proper error handling or
  * want to store to a `GFile` or other location, you might want to
@@ -548,30 +687,121 @@ gboolean
 gdk_texture_save_to_png (GdkTexture *texture,
                          const char *filename)
 {
-  cairo_surface_t *surface;
-  cairo_status_t status;
+  int width, height, stride;
+  GBytes *bytes;
+  GdkMemoryFormat format;
   gboolean result;
+  GFile *file;
+  GOutputStream *stream;
 
   g_return_val_if_fail (GDK_IS_TEXTURE (texture), FALSE);
   g_return_val_if_fail (filename != NULL, FALSE);
 
-  surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
-                                        gdk_texture_get_width (texture),
-                                        gdk_texture_get_height (texture));
-  gdk_texture_download (texture,
-                        cairo_image_surface_get_data (surface),
-                        cairo_image_surface_get_stride (surface));
-  cairo_surface_mark_dirty (surface);
+  width = gdk_texture_get_width (texture);
+  height = gdk_texture_get_height (texture);
 
-  status = cairo_surface_write_to_png (surface, filename);
-
-  if (status != CAIRO_STATUS_SUCCESS ||
-      cairo_surface_status (surface) != CAIRO_STATUS_SUCCESS)
-    result = FALSE;
+  bytes = gdk_texture_download_format (texture, GDK_MEMORY_R16G16B16A16_PREMULTIPLIED);
+  if (bytes)
+    {
+      format = GDK_MEMORY_R16G16B16A16_PREMULTIPLIED;
+      stride = width * 8;
+    }
   else
-    result = TRUE;
+    {
+      gpointer data;
 
-  cairo_surface_destroy (surface);
+      stride = width * 4;
+      data = g_malloc (stride * height);
+
+      gdk_texture_download (texture, data, stride);
+
+      bytes = g_bytes_new_take (data, stride * height);
+
+      format = GDK_MEMORY_DEFAULT;
+    }
+
+  file = g_file_new_for_path (filename);
+  stream = G_OUTPUT_STREAM (g_file_replace (file, NULL, FALSE,
+                                            G_FILE_CREATE_NONE,
+                                            NULL, NULL));
+  g_object_unref (file);
+
+  result = gdk_save_png (stream,
+                         g_bytes_get_data (bytes, NULL),
+                         width, height, stride,
+                         format,
+                         NULL);
+
+  g_output_stream_close (stream, NULL, NULL);
+  g_object_unref (stream);
+
+  g_bytes_unref (bytes);
+
+  return result;
+}
+
+/**
+ * gdk_texture_save_to_file:
+ * @texture: a `GdkTexture`
+ * @filename: (type filename): the filename to store to
+ *
+ * Store the given @texture to the @filename.
+ *
+ * GTK will choose a suitable file format to save the data in
+ * depending on the format of the texture. Currently, that is
+ * tiff, for all kinds of textures.
+ *
+ * This is a utility function intended for debugging and testing.
+ * If you want more control over formats, proper error handling or
+ * want to store to a `GFile` or other location, you might want to
+ * look into using the gdk-pixbuf library.
+ *
+ * Returns: %TRUE if saving succeeded, %FALSE on failure.
+ *
+ * Since: 4.6
+ */
+gboolean
+gdk_texture_save_to_file (GdkTexture  *texture,
+                          const char  *filename)
+{
+  GBytes *bytes = NULL;
+  gboolean result;
+  GdkMemoryFormat format;
+  GFile *file;
+  GOutputStream *stream;
+
+  g_return_val_if_fail (GDK_IS_TEXTURE (texture), FALSE);
+  g_return_val_if_fail (filename != NULL, FALSE);
+
+  for (int i = 0; i < GDK_MEMORY_N_FORMATS; i++)
+    {
+      bytes = gdk_texture_download_format (texture, i);
+      if (bytes)
+        {
+          format = i;
+          break;
+        }
+    }
+
+  if (!bytes)
+    return FALSE;
+
+  file = g_file_new_for_path (filename);
+  stream = G_OUTPUT_STREAM (g_file_replace (file, NULL, FALSE,
+                                            G_FILE_CREATE_NONE,
+                                            NULL, NULL));
+  g_object_unref (file);
+
+  result = gdk_save_tiff (stream,
+                          g_bytes_get_data (bytes, NULL),
+                          gdk_texture_get_width (texture),
+                          gdk_texture_get_height (texture),
+                          gdk_texture_get_width (texture) * gdk_memory_format_bytes_per_pixel (format),
+                          format,
+                          NULL);
+
+  g_clear_object (&stream);
+  g_clear_pointer (&bytes, g_bytes_unref);
 
   return result;
 }

gdk/gdktexture.h

@@ -59,9 +59,15 @@ GDK_AVAILABLE_IN_ALL
 void                    gdk_texture_download                   (GdkTexture      *texture,
                                                                 guchar          *data,
                                                                 gsize            stride);
+GDK_AVAILABLE_IN_4_6
+void                    gdk_texture_download_float             (GdkTexture      *texture,
+                                                                float           *data);
 GDK_AVAILABLE_IN_ALL
 gboolean                gdk_texture_save_to_png                (GdkTexture      *texture,
                                                                 const char      *filename);
+GDK_AVAILABLE_IN_4_6
+gboolean                gdk_texture_save_to_file               (GdkTexture      *texture,
+                                                                const char      *filename);
 
 G_END_DECLS
 

gdk/gdktextureprivate.h

@@ -2,6 +2,7 @@
 #define __GDK_TEXTURE_PRIVATE_H__
 
 #include "gdktexture.h"
+#include "gdkmemorytexture.h"
 
 G_BEGIN_DECLS
 
@@ -28,6 +29,8 @@ struct _GdkTextureClass {
                                                          const GdkRectangle     *area,
                                                          guchar                 *data,
                                                          gsize                   stride);
+  GBytes *              (* download_format)             (GdkTexture             *texture,
+                                                         GdkMemoryFormat         format);
 };
 
 gpointer                gdk_texture_new                 (const GdkTextureClass  *klass,
@@ -48,6 +51,11 @@ void                    gdk_texture_clear_render_data   (GdkTexture
 gpointer                gdk_texture_get_render_data     (GdkTexture             *self,
                                                          gpointer                key);
 
+GBytes *                gdk_texture_download_format     (GdkTexture             *texture,
+                                                         GdkMemoryFormat         format);
+GBytes *                gdk_texture_convert_format      (GdkTexture             *texture,
+                                                         GdkMemoryFormat         format);
+
 G_END_DECLS
 
 #endif /* __GDK_TEXTURE_PRIVATE_H__ */

gdk/gdktiff.c

@@ -0,0 +1,628 @@
+/* GDK - The GIMP Drawing Kit
+ * Copyright (C) 2021 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "gdktiff.h"
+
+#include "gdktexture.h"
+#include "gdkmemorytextureprivate.h"
+#include <tiffio.h>
+
+/* {{{ IO handling */
+
+typedef struct
+{
+  GObject *stream;
+  GInputStream *input;
+  GOutputStream *output;
+
+  gchar *buffer;
+  gsize allocated;
+  gsize used;
+  gsize position;
+} TiffIO;
+
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wsuggest-attribute=format"
+
+static void
+tiff_io_warning (const char *module,
+                 const char *fmt,
+                 va_list     ap)
+{
+  g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_MESSAGE, fmt, ap);
+}
+
+static void
+tiff_io_error (const char *module,
+               const char *fmt,
+               va_list     ap)
+{
+  g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_MESSAGE, fmt, ap);
+}
+
+#pragma GCC diagnostic pop
+
+static tsize_t
+tiff_io_read (thandle_t handle,
+              tdata_t   buffer,
+              tsize_t   size)
+{
+  TiffIO *io = (TiffIO *) handle;
+  GError *error = NULL;
+  gssize read  = -1;
+  gsize bytes_read = 0;
+
+  if (! g_input_stream_read_all (io->input,
+                                 (void *) buffer, (gsize) size,
+                                 &bytes_read,
+                                 NULL, &error))
+    {
+      g_printerr ("%s", error->message);
+      g_clear_error (&error);
+    }
+
+  read = bytes_read;
+
+  return (tsize_t) read;
+}
+
+static tsize_t
+tiff_io_write (thandle_t handle,
+               tdata_t   buffer,
+               tsize_t   size)
+{
+  TiffIO *io = (TiffIO *) handle;
+  GError *error = NULL;
+  gssize written = -1;
+  gsize bytes_written = 0;
+
+  if (! g_output_stream_write_all (io->output,
+                                   (void *) buffer, (gsize) size,
+                                   &bytes_written,
+                                   NULL, &error))
+    {
+      g_printerr ("%s", error->message);
+      g_clear_error (&error);
+    }
+
+  written = bytes_written;
+
+  return (tsize_t) written;
+}
+
+static GSeekType
+lseek_to_seek_type (int whence)
+{
+  switch (whence)
+    {
+    default:
+    case SEEK_SET:
+      return G_SEEK_SET;
+    case SEEK_CUR:
+      return G_SEEK_CUR;
+    case SEEK_END:
+      return G_SEEK_END;
+    }
+}
+
+static toff_t
+tiff_io_seek (thandle_t handle,
+              toff_t    offset,
+              int       whence)
+{
+  TiffIO *io = (TiffIO *) handle;
+  GError *error = NULL;
+  gboolean sought = FALSE;
+  goffset position = -1;
+
+  sought = g_seekable_seek (G_SEEKABLE (io->stream),
+                            (goffset) offset, lseek_to_seek_type (whence),
+                            NULL, &error);
+  if (sought)
+    {
+      position = g_seekable_tell (G_SEEKABLE (io->stream));
+    }
+  else
+    {
+      g_printerr ("%s", error->message);
+      g_clear_error (&error);
+    }
+
+  return (toff_t) position;
+}
+
+static int
+tiff_io_close (thandle_t handle)
+{
+  TiffIO *io = (TiffIO *) handle;
+  GError *error = NULL;
+  gboolean closed = FALSE;
+
+  if (io->input)
+    closed = g_input_stream_close (io->input, NULL, &error);
+  else if (io->output)
+    closed = g_output_stream_close (io->output, NULL, &error);
+
+  if (!closed)
+    {
+      g_printerr ("%s", error->message);
+      g_clear_error (&error);
+    }
+
+  g_clear_object (&io->stream);
+  io->input = NULL;
+  io->output = NULL;
+
+  g_clear_pointer (&io->buffer, g_free);
+
+  io->allocated = 0;
+  io->used = 0;
+  io->position  = 0;
+
+  g_free (io);
+
+  return closed ? 0 : -1;
+}
+
+static goffset
+input_stream_query_size (GInputStream *stream)
+{
+  goffset size = 0;
+
+  while (G_IS_FILTER_INPUT_STREAM (stream))
+    stream = g_filter_input_stream_get_base_stream (G_FILTER_INPUT_STREAM (stream));
+
+  if (G_IS_FILE_INPUT_STREAM (stream))
+    {
+      GFileInfo *info;
+
+      info = g_file_input_stream_query_info (G_FILE_INPUT_STREAM (stream),
+                                             G_FILE_ATTRIBUTE_STANDARD_SIZE,
+                                             NULL,
+                                             NULL);
+      if (info)
+        {
+          size = g_file_info_get_size (info);
+          g_object_unref (info);
+        }
+    }
+
+  return size;
+}
+
+static goffset
+output_stream_query_size (GOutputStream *stream)
+{
+  goffset size = 0;
+
+  while (G_IS_FILTER_OUTPUT_STREAM (stream))
+    stream = g_filter_output_stream_get_base_stream (G_FILTER_OUTPUT_STREAM (stream));
+
+  if (G_IS_FILE_OUTPUT_STREAM (stream))
+    {
+      GFileInfo *info;
+
+      info = g_file_output_stream_query_info (G_FILE_OUTPUT_STREAM (stream),
+                                              G_FILE_ATTRIBUTE_STANDARD_SIZE,
+                                              NULL,
+                                              NULL);
+      if (info)
+        {
+          size = g_file_info_get_size (info);
+          g_object_unref (info);
+        }
+    }
+
+  return size;
+}
+
+static toff_t
+tiff_io_get_file_size (thandle_t handle)
+{
+  TiffIO *io = (TiffIO *) handle;
+
+  if (io->input)
+    return (toff_t) input_stream_query_size (io->input);
+  else if (io->output)
+    return (toff_t) output_stream_query_size (io->output);
+
+  return (toff_t) 0;
+}
+
+static TIFF *
+tiff_open (gpointer      stream,
+           const gchar  *mode,
+           GError      **error)
+{
+  TIFFSetWarningHandler ((TIFFErrorHandler) tiff_io_warning);
+  TIFFSetErrorHandler ((TIFFErrorHandler) tiff_io_error);
+  TiffIO *io;
+
+  io = g_new0 (TiffIO, 1);
+
+  if (strcmp (mode, "r") == 0)
+    {
+      io->input = G_INPUT_STREAM (stream);
+      io->stream = g_object_ref (G_OBJECT (stream));
+    }
+  else if (strcmp (mode, "w") == 0)
+    {
+      io->output = G_OUTPUT_STREAM (stream);
+      io->stream = g_object_ref (G_OBJECT (stream));
+    }
+  else
+    {
+      g_assert_not_reached ();
+    }
+
+  return TIFFClientOpen ("GTK", mode,
+                         (thandle_t) io,
+                         tiff_io_read,
+                         tiff_io_write,
+                         tiff_io_seek,
+                         tiff_io_close,
+                         tiff_io_get_file_size,
+                         NULL, NULL);
+}
+
+/* }}} */
+/* {{{ Public API */
+
+static struct {
+  GdkMemoryFormat format;
+  guint16 bits_per_sample;
+  guint16 samples_per_pixel;
+  guint16 sample_format;
+} format_data[] = {
+  { GDK_MEMORY_DEFAULT,                     8, 4, SAMPLEFORMAT_UINT   },
+  { GDK_MEMORY_R8G8B8,                      8, 3, SAMPLEFORMAT_UINT   },
+  { GDK_MEMORY_R16G16B16A16_PREMULTIPLIED, 16, 4, SAMPLEFORMAT_UINT   },
+  { GDK_MEMORY_R16G16B16_FLOAT,            16, 3, SAMPLEFORMAT_IEEEFP },
+  { GDK_MEMORY_R32G32B32_FLOAT,            32, 3, SAMPLEFORMAT_IEEEFP },
+};
+
+gboolean
+gdk_save_tiff (GOutputStream    *stream,
+               const guchar     *data,
+               int               width,
+               int               height,
+               int               stride,
+               GdkMemoryFormat   format,
+               GError          **error)
+{
+  TIFF *tif;
+  guint16 bits_per_sample = 0;
+  guint16 samples_per_pixel = 0;
+  guint16 sample_format = 0;
+  const guchar *line;
+
+  tif = tiff_open (stream, "w", error);
+  if (!tif)
+    return FALSE;
+
+  for (int i = 0; i < G_N_ELEMENTS (format_data); i++)
+    {
+      if (format == format_data[i].format)
+        {
+          bits_per_sample = format_data[i].bits_per_sample;
+          samples_per_pixel = format_data[i].samples_per_pixel;
+          sample_format = format_data[i].sample_format;
+          break;
+        }
+    }
+
+  g_assert (bits_per_sample != 0);
+
+  TIFFSetField (tif, TIFFTAG_SOFTWARE, "GTK");
+  TIFFSetField (tif, TIFFTAG_IMAGEWIDTH, width);
+  TIFFSetField (tif, TIFFTAG_IMAGELENGTH, height);
+  TIFFSetField (tif, TIFFTAG_BITSPERSAMPLE, bits_per_sample);
+  TIFFSetField (tif, TIFFTAG_SAMPLESPERPIXEL, samples_per_pixel);
+  TIFFSetField (tif, TIFFTAG_SAMPLEFORMAT, sample_format);
+  TIFFSetField (tif, TIFFTAG_ORIENTATION, ORIENTATION_TOPLEFT);
+  TIFFSetField (tif, TIFFTAG_COMPRESSION, COMPRESSION_NONE);
+  // TODO: save gamma / colorspace
+
+  if (samples_per_pixel > 3)
+    {
+      guint16 extra_samples[] = { EXTRASAMPLE_ASSOCALPHA };
+      TIFFSetField (tif, TIFFTAG_EXTRASAMPLES, 1, extra_samples);
+    }
+
+  TIFFSetField (tif, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_RGB);
+  TIFFSetField (tif, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
+
+  line = (const guchar *)data;
+  for (int y = 0; y < height; y++)
+    {
+      if (TIFFWriteScanline (tif, (void *)line, y, 0) == -1)
+        {
+          g_set_error (error,
+                       G_IO_ERROR, G_IO_ERROR_FAILED,
+                       "Writing data failed at row %d", y);
+          TIFFClose (tif);
+          return FALSE;
+        }
+
+      line += stride;
+    }
+
+  TIFFFlushData (tif);
+  TIFFClose (tif);
+
+  return TRUE;
+}
+
+static GdkTexture *
+load_fallback (TIFF    *tif,
+               GError **error)
+{
+  int width, height;
+  guchar *pixels;
+  GBytes *bytes;
+  GdkTexture *texture;
+
+  TIFFGetField (tif, TIFFTAG_IMAGEWIDTH, &width);
+  TIFFGetField (tif, TIFFTAG_IMAGELENGTH, &height);
+
+  pixels = g_malloc (width * height * 4);
+
+  if (!TIFFReadRGBAImageOriented (tif, width, height, (uint32 *)pixels, ORIENTATION_TOPLEFT, 1))
+    {
+      g_set_error_literal (error,
+                           G_IO_ERROR, G_IO_ERROR_FAILED,
+                           "Failed to load RGB data from TIFF file");
+      g_free (pixels);
+      return NULL;
+    }
+
+  bytes = g_bytes_new_take (pixels, width * height * 4);
+
+  texture = gdk_memory_texture_new (width, height,
+                                    GDK_MEMORY_R8G8B8A8_PREMULTIPLIED,
+                                    bytes,
+                                    width * 4);
+
+  g_bytes_unref (bytes);
+
+  return texture;
+}
+
+/* This isn't meant to be a very versatile tiff loader.
+ * It just aims to load the subset that we're saving
+ * ourselves, above.
+ */
+GdkTexture *
+gdk_load_tiff (GInputStream     *stream,
+               GError          **error)
+{
+  TIFF *tif;
+  guint16 samples_per_pixel;
+  guint16 bits_per_sample;
+  guint16 photometric;
+  guint16 planarconfig;
+  guint16 sample_format;
+  guint16 orientation;
+  guint32 width, height;
+  GdkMemoryFormat format;
+  guchar *data, *line;
+  gsize stride;
+  int bpp;
+  GBytes *bytes;
+  GdkTexture *texture;
+
+  tif = tiff_open (stream, "r", error);
+  if (!tif)
+    return NULL;
+
+  TIFFSetDirectory (tif, 0);
+
+  TIFFGetFieldDefaulted (tif, TIFFTAG_SAMPLESPERPIXEL, &samples_per_pixel);
+  TIFFGetFieldDefaulted (tif, TIFFTAG_BITSPERSAMPLE, &bits_per_sample);
+  TIFFGetFieldDefaulted (tif, TIFFTAG_SAMPLEFORMAT, &sample_format);
+  TIFFGetFieldDefaulted (tif, TIFFTAG_PHOTOMETRIC, &photometric);
+  TIFFGetFieldDefaulted (tif, TIFFTAG_PLANARCONFIG, &planarconfig);
+  TIFFGetFieldDefaulted (tif, TIFFTAG_ORIENTATION, &orientation);
+  TIFFGetFieldDefaulted (tif, TIFFTAG_IMAGEWIDTH, &width);
+  TIFFGetFieldDefaulted (tif, TIFFTAG_IMAGELENGTH, &height);
+
+  if (samples_per_pixel == 4)
+    {
+      guint16 extra;
+      guint16 *extra_types;
+
+      if (!TIFFGetField (tif, TIFFTAG_EXTRASAMPLES, &extra, &extra_types))
+        extra = 0;
+
+      if (extra == 0 || extra_types[0] != EXTRASAMPLE_ASSOCALPHA)
+        {
+          texture = load_fallback (tif, error);
+          TIFFClose (tif);
+          return texture;
+        }
+    }
+
+  format = 0;
+
+  for (int i = 0; i < G_N_ELEMENTS (format_data); i++)
+    {
+      if (format_data[i].sample_format == sample_format &&
+          format_data[i].bits_per_sample == bits_per_sample &&
+          format_data[i].samples_per_pixel == samples_per_pixel)
+        {
+          format = format_data[i].format;
+          break;
+        }
+    }
+
+  if (format == 0 ||
+      photometric != PHOTOMETRIC_RGB ||
+      planarconfig != PLANARCONFIG_CONTIG ||
+      TIFFIsTiled (tif) ||
+      orientation != ORIENTATION_TOPLEFT)
+    {
+      texture = load_fallback (tif, error);
+      TIFFClose (tif);
+      return texture;
+    }
+
+  stride = width * gdk_memory_format_bytes_per_pixel (format);
+
+  g_assert (TIFFScanlineSize (tif) == stride);
+
+  data = g_new (guchar, height * stride);
+
+  line = data;
+  for (int y = 0; y < height; y++)
+    {
+      if (TIFFReadScanline (tif, line, y, 0) == -1)
+        {
+          g_set_error (error,
+                       G_IO_ERROR, G_IO_ERROR_FAILED,
+                       "Reading data failed at row %d", y);
+          TIFFClose (tif);
+          g_free (data);
+          return NULL;
+        }
+
+      line += stride;
+    }
+
+  bpp = gdk_memory_format_bytes_per_pixel (format);
+  bytes = g_bytes_new_take (data, width * height * bpp);
+
+  texture = gdk_memory_texture_new (width, height,
+                                    format,
+                                    bytes, width * bpp);
+  g_bytes_unref (bytes);
+
+  return texture;
+}
+
+/* }}} */
+/* {{{ Async code */
+
+static void
+load_tiff_in_thread (GTask        *task,
+                     gpointer      source_object,
+                     gpointer      task_data,
+                     GCancellable *cancellable)
+{
+  GInputStream *stream = source_object;
+  GdkTexture *texture;
+  GError *error = NULL;
+
+  texture = gdk_load_tiff (stream, &error);
+
+  if (texture)
+    g_task_return_pointer (task, texture, g_object_unref);
+  else
+    g_task_return_error (task, error);
+}
+
+void
+gdk_load_tiff_async (GInputStream         *stream,
+                     GCancellable         *cancellable,
+                     GAsyncReadyCallback   callback,
+                     gpointer              user_data)
+{
+  GTask *task;
+
+  task = g_task_new (stream, cancellable, callback, user_data);
+  g_task_run_in_thread (task, load_tiff_in_thread);
+  g_object_unref (task);
+}
+
+GdkTexture *
+gdk_load_tiff_finish (GAsyncResult  *result,
+                      GError       **error)
+{
+  return g_task_propagate_pointer (G_TASK (result), error);
+}
+
+typedef struct {
+  const guchar *data;
+  int width;
+  int height;
+  int stride;
+  GdkMemoryFormat format;
+} SaveTiffData;
+
+static void
+save_tiff_in_thread (GTask        *task,
+                     gpointer      source_object,
+                     gpointer      task_data,
+                     GCancellable *cancellable)
+{
+  GOutputStream *stream = source_object;
+  SaveTiffData *data = task_data;
+  GError *error = NULL;
+  gboolean result;
+
+  result = gdk_save_tiff (stream,
+                          data->data,
+                          data->width,
+                          data->height,
+                          data->stride,
+                          data->format,
+                          &error);
+
+  if (result)
+    g_task_return_boolean (task, result);
+  else
+    g_task_return_error (task, error);
+}
+
+void
+gdk_save_tiff_async (GOutputStream          *stream,
+                     const guchar           *data,
+                     int                     width,
+                     int                     height,
+                     int                     stride,
+                     GdkMemoryFormat         format,
+                     GCancellable           *cancellable,
+                     GAsyncReadyCallback     callback,
+                     gpointer                user_data)
+{
+  GTask *task;
+  SaveTiffData *save_data;
+
+  save_data = g_new0 (SaveTiffData, 1);
+  save_data->data = data;
+  save_data->width = width;
+  save_data->height = height;
+  save_data->stride = stride;
+  save_data->format = format;
+
+  task = g_task_new (stream, cancellable, callback, user_data);
+  g_task_set_task_data (task, save_data, g_free);
+  g_task_run_in_thread (task, save_tiff_in_thread);
+  g_object_unref (task);
+}
+
+gboolean
+gdk_save_tiff_finish (GAsyncResult  *result,
+                      GError       **error)
+{
+  return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+/* }}} */
+
+/* vim:set foldmethod=marker expandtab: */

gdk/gdktiff.h

@@ -0,0 +1,56 @@
+/* GDK - The GIMP Drawing Kit
+ * Copyright (C) 2021 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GDK_TIFF_H__
+#define __GDK_TIFF_H__
+
+#include "gdkmemorytexture.h"
+#include <gio/gio.h>
+
+GdkTexture *gdk_load_tiff         (GInputStream     *stream,
+                                   GError          **error);
+
+void        gdk_load_tiff_async   (GInputStream           *stream,
+                                   GCancellable           *cancellable,
+                                   GAsyncReadyCallback     callback,
+                                   gpointer                user_data);
+
+GdkTexture *gdk_load_tiff_finish  (GAsyncResult           *result,
+                                   GError                **error);
+
+gboolean    gdk_save_tiff         (GOutputStream    *stream,
+                                   const guchar     *data,
+                                   int               width,
+                                   int               height,
+                                   int               stride,
+                                   GdkMemoryFormat   format,
+                                   GError          **error);
+
+void        gdk_save_tiff_async  (GOutputStream          *stream,
+                                  const guchar           *data,
+                                  int                     width,
+                                  int                     height,
+                                  int                     stride,
+                                  GdkMemoryFormat         format,
+                                  GCancellable           *cancellable,
+                                  GAsyncReadyCallback     callback,
+                                  gpointer                user_data);
+
+gboolean    gdk_save_tiff_finish (GAsyncResult           *result,
+                                  GError                **error);
+
+#endif

gdk/meson.build

@@ -50,6 +50,9 @@ gdk_public_sources = files([
   'gdktoplevelsize.c',
   'gdktoplevel.c',
   'gdkdragsurface.c',
+  'gdkpng.c',
+  'gdktiff.c',
+  'gdkjpeg.c',
 ])
 
 gdk_public_headers = files([
@@ -254,8 +257,8 @@ endif
 
 libgdk = static_library('gdk',
   sources: [gdk_sources, gdk_backends_gen_headers, gdkconfig],
-  dependencies: gdk_deps + [libgtk_css_dep],
-  link_with: [libgtk_css, ],
+  dependencies: gdk_deps + [libgtk_css_dep, png_dep, tiff_dep, jpeg_dep],
+  link_with: [libgtk_css],
   include_directories: [confinc, gdkx11_inc, wlinc],
   c_args: libgdk_c_args + common_cflags,
   link_whole: gdk_backends,

meson.build

@@ -199,6 +199,7 @@ check_functions = [
   'mallinfo2',
   'sincos',
   'sincosf',
+  'fopencookie',
 ]
 
 foreach func : check_functions
@@ -389,6 +390,9 @@ pangocairo_dep = dependency('pangocairo', version: pango_req,
 pixbuf_dep     = dependency('gdk-pixbuf-2.0', version: gdk_pixbuf_req,
                             fallback : ['gdk-pixbuf', 'gdkpixbuf_dep'],
                             default_options: ['png=enabled', 'jpeg=enabled', 'builtin_loaders=png,jpeg', 'man=false'])
+png_dep        = dependency('libpng16')
+tiff_dep        = dependency('libtiff-4')
+jpeg_dep       = dependency('libjpeg')
 epoxy_dep      = dependency('epoxy', version: epoxy_req,
                             fallback: ['libepoxy', 'libepoxy_dep'])
 harfbuzz_dep   = dependency('harfbuzz', version: '>= 2.1.0', required: false,

testsuite/gdk/memorytexture.c

@@ -2,7 +2,7 @@
 #include <gdk/gdk.h>
 
 /* maximum bytes per pixel */
-#define MAX_BPP 4
+#define MAX_BPP 8
 
 typedef enum {
   BLUE,
@@ -33,6 +33,7 @@ typedef struct _TestData {
 } TestData;
 
 #define RGBA(a, b, c, d) { 0x ## a, 0x ## b, 0x ## c, 0x ## d }
+#define RGBA16(a, b, c, d) { 0x ## a, 0x ## a, 0x ## b, 0x ## b, 0x ## c, 0x ## c, 0x ## d, 0x ## d }
 
 static MemoryData tests[GDK_MEMORY_N_FORMATS] = {
   { 4, FALSE, { RGBA(FF,00,00,FF), RGBA(00,FF,00,FF), RGBA(00,00,FF,FF), RGBA(00,00,00,00), RGBA(66,22,44,AA) } },
@@ -44,12 +45,14 @@ static MemoryData tests[GDK_MEMORY_N_FORMATS] = {
   { 4, FALSE, { RGBA(FF,FF,00,00), RGBA(FF,00,FF,00), RGBA(FF,00,00,FF), RGBA(00,00,00,00), RGBA(AA,99,33,66) } },
   { 3, TRUE,  { RGBA(00,00,FF,00), RGBA(00,FF,00,00), RGBA(FF,00,00,00), RGBA(00,00,00,00), RGBA(44,22,66,00) } },
   { 3, TRUE,  { RGBA(FF,00,00,00), RGBA(00,FF,00,00), RGBA(00,00,FF,00), RGBA(00,00,00,00), RGBA(66,22,44,00) } },
+  { 8, FALSE, { RGBA16(00,00,FF,FF), RGBA16(00,FF,00,FF), RGBA16(FF,00,00,FF), RGBA16(00,00,00,00), RGBA16(44,22,66,AA) } },
 };
 
 static void
 compare_textures (GdkTexture *expected,
                   GdkTexture *test,
-                  gboolean    ignore_alpha)
+                  gboolean    ignore_alpha,
+                  int         bpp)
 {
   guchar *expected_data, *test_data;
   int width, height;
@@ -122,7 +125,7 @@ test_download_1x1 (gconstpointer data)
   expected = create_texture (GDK_MEMORY_DEFAULT, test_data->color, 1, 1, tests[test_data->format].bytes_per_pixel);
   test = create_texture (test_data->format, test_data->color, 1, 1, tests[test_data->format].bytes_per_pixel);
 
-  compare_textures (expected, test, tests[test_data->format].opaque);
+  compare_textures (expected, test, tests[test_data->format].opaque, tests[test_data->format].bytes_per_pixel);
 
   g_object_unref (expected);
   g_object_unref (test);
@@ -137,7 +140,7 @@ test_download_1x1_with_stride (gconstpointer data)
   expected = create_texture (GDK_MEMORY_DEFAULT, test_data->color, 1, 1, 4);
   test = create_texture (test_data->format, test_data->color, 1, 1, 2 * MAX_BPP);
 
-  compare_textures (expected, test, tests[test_data->format].opaque);
+  compare_textures (expected, test, tests[test_data->format].opaque, tests[test_data->format].bytes_per_pixel);
 
   g_object_unref (expected);
   g_object_unref (test);
@@ -152,7 +155,7 @@ test_download_4x4 (gconstpointer data)
   expected = create_texture (GDK_MEMORY_DEFAULT, test_data->color, 4, 4, 16);
   test = create_texture (test_data->format, test_data->color, 4, 4, 4 * tests[test_data->format].bytes_per_pixel);
 
-  compare_textures (expected, test, tests[test_data->format].opaque);
+  compare_textures (expected, test, tests[test_data->format].opaque, tests[test_data->format].bytes_per_pixel);
 
   g_object_unref (expected);
   g_object_unref (test);
@@ -167,7 +170,7 @@ test_download_4x4_with_stride (gconstpointer data)
   expected = create_texture (GDK_MEMORY_DEFAULT, test_data->color, 4, 4, 16);
   test = create_texture (test_data->format, test_data->color, 4, 4, 4 * MAX_BPP);
 
-  compare_textures (expected, test, tests[test_data->format].opaque);
+  compare_textures (expected, test, tests[test_data->format].opaque, tests[test_data->format].bytes_per_pixel);
 
   g_object_unref (expected);
   g_object_unref (test);
@@ -186,6 +189,12 @@ main (int argc, char *argv[])
 
   for (format = 0; format < GDK_MEMORY_N_FORMATS; format++)
     {
+      if (format == GDK_MEMORY_R16G16B16_FLOAT ||
+          format == GDK_MEMORY_R16G16B16A16_FLOAT_PREMULTIPLIED ||
+          format == GDK_MEMORY_R32G32B32_FLOAT ||
+          format == GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED)
+        continue;
+
       for (color = 0; color < N_COLORS; color++)
         {
           TestData *test_data = g_new (TestData, 1);