vulkan: implement subpixel positioning

Pass the glyph position into the glyph caching functions, not just the glyph index. This allows us to cache different images for different subpixel positions.
gl: implement subpixel positioning
2018-07-28 22:34:05 -04:00 · 2018-07-28 21:34:37 -04:00 · 2018-07-28 21:34:37 -04:00 · 2018-07-28 11:34:28 -04:00 · 2018-07-27 18:42:22 -04:00
15 changed files with 513 additions and 35 deletions
--- a/demos/gtk-demo/demo.gresource.xml
+++ b/demos/gtk-demo/demo.gresource.xml
@@ -169,6 +169,7 @@
    <file>foreigndrawing.c</file>
    <file>font_features.c</file>
    <file>fontplane.c</file>
+    <file>fontrendering.c</file>
    <file>gestures.c</file>
    <file>glarea.c</file>
    <file>headerbar.c</file>
@@ -262,4 +263,7 @@
  <gresource prefix="/dnd">
    <file>dnd.css</file>
  </gresource>
+  <gresource prefix="/fontrendering">
+    <file>fontrendering.ui</file>
+  </gresource>
 </gresources>
--- a/demos/gtk-demo/fontrendering.c
+++ b/demos/gtk-demo/fontrendering.c
@@ -0,0 +1,222 @@
+/* Pango/Font Rendering
+ *
+ * Demonstrates variations in font rendering.
+ */
+
+#include <gtk/gtk.h>
+
+static GtkWidget *window = NULL;
+static GtkWidget *font_button = NULL;
+static GtkWidget *entry = NULL;
+static GtkWidget *image = NULL;
+static GtkWidget *hinting = NULL;
+static GtkWidget *hint_metrics = NULL;
+static GtkWidget *up_button = NULL;
+static GtkWidget *down_button = NULL;
+static GtkWidget *text_radio = NULL;
+
+static PangoContext *context;
+
+static int scale = 10;
+
+static void
+on_destroy (gpointer data)
+{
+  window = NULL;
+}
+
+static void
+update_image (void)
+{
+  const char *text;
+  PangoFontDescription *desc;
+  PangoLayout *layout;
+  PangoRectangle ink, logical;
+  cairo_surface_t *surface;
+  cairo_t *cr;
+  GdkPixbuf *pixbuf;
+  GdkPixbuf *pixbuf2;
+  const char *hint;
+  cairo_font_options_t *fopt;
+  cairo_hint_style_t hintstyle;
+  cairo_hint_metrics_t hintmetrics;
+
+  if (!context)
+    context = gtk_widget_create_pango_context (image);
+
+  text = gtk_entry_get_text (GTK_ENTRY (entry));
+  desc = gtk_font_chooser_get_font_desc (GTK_FONT_CHOOSER (font_button));  
+
+  fopt = cairo_font_options_copy (pango_cairo_context_get_font_options (context));
+
+  hint = gtk_combo_box_get_active_id (GTK_COMBO_BOX (hinting));
+  if (strcmp (hint, "none") == 0)
+    hintstyle = CAIRO_HINT_STYLE_NONE;
+  else if (strcmp (hint, "slight") == 0)
+    hintstyle = CAIRO_HINT_STYLE_SLIGHT;
+  else if (strcmp (hint, "medium") == 0)
+    hintstyle = CAIRO_HINT_STYLE_MEDIUM;
+  else if (strcmp (hint, "full") == 0)
+    hintstyle = CAIRO_HINT_STYLE_FULL;
+  else
+    hintstyle = CAIRO_HINT_STYLE_DEFAULT;
+  cairo_font_options_set_hint_style (fopt, hintstyle);
+
+  if (gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (hint_metrics)))
+    hintmetrics = CAIRO_HINT_METRICS_ON;
+  else
+    hintmetrics = CAIRO_HINT_METRICS_OFF;
+  cairo_font_options_set_hint_metrics (fopt, hintmetrics);
+
+  pango_cairo_context_set_font_options (context, fopt);
+  cairo_font_options_destroy (fopt);
+
+  if (gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (text_radio)))
+    {
+      layout = pango_layout_new (context);
+      pango_layout_set_font_description (layout, desc);
+      pango_layout_set_text (layout, text, -1);
+      pango_layout_get_extents (layout, &ink, &logical);
+
+      pango_extents_to_pixels (&logical, NULL);
+
+      surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
+                                            MAX(1,logical.width),
+                                            MAX(1,logical.height));
+      cr = cairo_create (surface);
+      cairo_set_source_rgb (cr, 1, 1, 1);
+      cairo_paint (cr);
+
+      cairo_set_source_rgb (cr, 0, 0, 0);
+      pango_cairo_show_layout (cr, layout);
+
+      cairo_destroy (cr);
+      g_object_unref (layout);
+    }
+  else
+    {
+      PangoLayoutIter *iter;
+      PangoGlyphItem *run;
+      PangoGlyphInfo *g;
+      int i, j;
+
+      layout = pango_layout_new (context);
+      pango_layout_set_font_description (layout, desc);
+      pango_layout_set_text (layout, "aaaa", -1);
+      pango_layout_get_extents (layout, &ink, &logical);
+      pango_extents_to_pixels (&logical, NULL);
+
+      iter = pango_layout_get_iter (layout);
+      run = pango_layout_iter_get_run (iter);
+
+      surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
+                                            MAX(1, logical.width) * 3 / 2,
+                                            MAX(1, logical.height) * 4);
+      cr = cairo_create (surface);
+      cairo_set_source_rgb (cr, 1, 1, 1);
+      cairo_paint (cr);
+
+      cairo_set_source_rgb (cr, 0, 0, 0);
+      for (i = 0; i < 4; i++)
+        {
+          g = &(run->glyphs->glyphs[i]);
+          g->geometry.width = PANGO_UNITS_ROUND (g->geometry.width * 3 / 2);
+        }
+ 
+      for (j = 0; j < 4; j++)
+        {
+          for (i = 0; i < 4; i++)
+            {
+              g = &(run->glyphs->glyphs[i]);
+              g->geometry.x_offset = i * (PANGO_SCALE / 4);
+              g->geometry.y_offset = j * (PANGO_SCALE / 4);
+            }
+
+          cairo_move_to (cr, 0, j * logical.height);
+          pango_cairo_show_layout (cr, layout);
+        }
+
+      cairo_destroy (cr);
+      pango_layout_iter_free (iter);
+      g_object_unref (layout);
+    }
+
+  pixbuf = gdk_pixbuf_get_from_surface (surface, 0, 0, cairo_image_surface_get_width (surface), cairo_image_surface_get_height (surface));
+  pixbuf2 = gdk_pixbuf_scale_simple (pixbuf, gdk_pixbuf_get_width (pixbuf) * scale, gdk_pixbuf_get_height (pixbuf) * scale, GDK_INTERP_NEAREST);
+
+  gtk_picture_set_pixbuf (GTK_PICTURE (image), pixbuf2);
+
+  g_object_unref (pixbuf);
+  g_object_unref (pixbuf2);
+
+  cairo_surface_destroy (surface);
+  pango_font_description_free (desc);
+}
+
+static void
+update_buttons (void)
+{
+  gtk_widget_set_sensitive (up_button, scale < 32);
+  gtk_widget_set_sensitive (down_button, scale > 1);
+}
+
+static void
+scale_up (void)
+{
+  scale += 1;
+  update_buttons ();
+  update_image ();
+}
+
+static void
+scale_down (void)
+{
+  scale -= 1;
+  update_buttons ();
+  update_image ();
+}
+
+GtkWidget *
+do_fontrendering (GtkWidget *do_widget)
+{
+  if (!window)
+    {
+      GtkBuilder *builder;
+
+      builder = gtk_builder_new_from_resource ("/fontrendering/fontrendering.ui");
+      gtk_builder_connect_signals (builder, NULL);
+      window = GTK_WIDGET (gtk_builder_get_object (builder, "window"));
+      gtk_window_set_display (GTK_WINDOW (window),
+                              gtk_widget_get_display (do_widget));
+      g_signal_connect (window, "destroy",
+                        G_CALLBACK (on_destroy), NULL);
+      g_object_set_data_full (G_OBJECT (window), "builder", builder, g_object_unref);
+      font_button = GTK_WIDGET (gtk_builder_get_object (builder, "font_button"));
+      up_button = GTK_WIDGET (gtk_builder_get_object (builder, "up_button"));
+      down_button = GTK_WIDGET (gtk_builder_get_object (builder, "down_button"));
+      entry = GTK_WIDGET (gtk_builder_get_object (builder, "entry"));
+      image = GTK_WIDGET (gtk_builder_get_object (builder, "image"));
+      hinting = GTK_WIDGET (gtk_builder_get_object (builder, "hinting"));
+      hint_metrics = GTK_WIDGET (gtk_builder_get_object (builder, "hint_metrics"));
+      text_radio = GTK_WIDGET (gtk_builder_get_object (builder, "text_radio")); 
+
+      g_signal_connect (up_button, "clicked", G_CALLBACK (scale_up), NULL);
+      g_signal_connect (down_button, "clicked", G_CALLBACK (scale_down), NULL);
+      g_signal_connect (entry, "notify::text", G_CALLBACK (update_image), NULL);
+      g_signal_connect (font_button, "notify::font-desc", G_CALLBACK (update_image), NULL);
+      g_signal_connect (hinting, "notify::active", G_CALLBACK (update_image), NULL);
+      g_signal_connect (hint_metrics, "notify::active", G_CALLBACK (update_image), NULL);
+      g_signal_connect (text_radio, "notify::active", G_CALLBACK (update_image), NULL);
+
+      update_image ();
+    }
+
+  if (!gtk_widget_get_visible (window))
+    gtk_widget_show (window);
+  else
+    {
+      gtk_widget_destroy (window);
+    }
+
+  return window;
+}
--- a/demos/gtk-demo/fontrendering.ui
+++ b/demos/gtk-demo/fontrendering.ui
@@ -0,0 +1,185 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<interface>
+  <!-- interface-requires gtk+ 3.94 -->
+  <object class="GtkAdjustment" id="scale_adj">
+    <property name="lower">0</property>
+    <property name="value">0</property>
+    <property name="upper">24</property>
+    <property name="step-increment">1</property>
+    <property name="page-increment">4</property>
+    <property name="page-size">0</property>
+  </object>
+  <object class="GtkWindow" id="window">
+    <property name="default-width">600</property>
+    <property name="default-height">300</property>
+    <property name="title">Font rendering</property>
+    <child>
+      <object class="GtkGrid">
+        <property name="margin-top">10</property>
+        <property name="row-spacing">10</property>
+        <property name="column-spacing">10</property>
+        <child>
+          <object class="GtkLabel">
+            <property name="margin-start">10</property>
+            <property name="label">Text</property>
+            <property name="xalign">1</property>
+            <style><class name="dim-label"/></style>
+          </object>
+          <packing>
+            <property name="left-attach">0</property>
+            <property name="top-attach">0</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkEntry" id="entry">
+            <property name="text">Fonts render</property>
+          </object>
+          <packing>
+            <property name="left-attach">1</property>
+            <property name="top-attach">0</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="margin-start">10</property>
+            <property name="label">Font</property>
+            <property name="xalign">1</property>
+            <style><class name="dim-label"/></style>
+          </object>
+          <packing>
+            <property name="left-attach">0</property>
+            <property name="top-attach">1</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkFontButton" id="font_button">
+          </object>
+          <packing>
+            <property name="left-attach">1</property>
+            <property name="top-attach">1</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="label">Hinting</property>
+            <property name="xalign">1</property>
+            <style><class name="dim-label"/></style>
+          </object>
+          <packing>
+            <property name="left-attach">2</property>
+            <property name="top-attach">0</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkComboBoxText" id="hinting">
+            <property name="active">0</property>
+            <property name="valign">center</property>
+            <items>
+              <item translatable="yes" id="none">None</item>
+              <item translatable="yes" id="slight">Slight</item>
+              <item translatable="yes" id="medium">Medium</item>
+              <item translatable="yes" id="full">Full</item>
+            </items>
+          </object>
+          <packing>
+            <property name="left-attach">3</property>
+            <property name="top-attach">0</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkCheckButton" id="hint_metrics">
+            <child>
+              <object class="GtkLabel">
+                <property name="label">Hint Metrics</property>
+                <style><class name="dim-label"/></style>
+              </object>
+            </child>
+          </object>
+          <packing>
+            <property name="left-attach">3</property>
+            <property name="top-attach">1</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkButton" id="up_button">
+            <property name="icon-name">list-add-symbolic</property>
+            <style><class name="circular"/></style>
+          </object>
+          <packing>
+            <property name="left-attach">4</property>
+            <property name="top-attach">0</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkButton" id="down_button">
+            <property name="icon-name">list-remove-symbolic</property>
+            <style><class name="circular"/></style>
+          </object>
+          <packing>
+            <property name="left-attach">4</property>
+            <property name="top-attach">1</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="label"></property>
+            <property name="hexpand">1</property>
+          </object>
+          <packing>
+            <property name="left-attach">6</property>
+            <property name="top-attach">0</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkBox">
+            <property name="orientation">horizontal</property>
+            <property name="halign">center</property>
+            <property name="valign">center</property>
+            <style><class name="linked"/></style>
+            <child>
+              <object class="GtkRadioButton" id="text_radio">
+                <property name="draw-indicator">0</property>
+                <property name="label">Text</property>
+              </object>
+            </child>
+            <child>
+              <object class="GtkRadioButton" id="grid_radio">
+                <property name="draw-indicator">0</property>
+                <property name="label">Grid</property>
+                <property name="group">text_radio</property>
+              </object>
+            </child>
+          </object>
+          <packing>
+            <property name="left-attach">0</property>
+            <property name="top-attach">3</property>
+            <property name="width">7</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkScrolledWindow">
+            <property name="hscrollbar-policy">automatic</property>
+            <property name="vscrollbar-policy">automatic</property>
+            <property name="propagate-natural-height">1</property>
+            <property name="shadow-type">in</property>
+            <property name="hexpand">1</property>
+            <property name="vexpand">1</property>
+            <child>
+              <object class="GtkPicture" id="image">
+                <property name="halign">center</property>
+                <property name="valign">center</property>
+                <property name="can-shrink">0</property>
+                <property name="keep-aspect-ratio">1</property>
+              </object>
+            </child>
+          </object>
+          <packing>
+            <property name="left-attach">0</property>
+            <property name="top-attach">4</property>
+            <property name="width">7</property>
+          </packing>
+        </child>
+      </object>
+    </child>
+  </object>
+</interface>
--- a/demos/gtk-demo/meson.build
+++ b/demos/gtk-demo/meson.build
@@ -26,6 +26,7 @@ demos = files([
  'expander.c',
  'filtermodel.c',
  'fishbowl.c',
+  'fontrendering.c',
  'foreigndrawing.c',
  'gestures.c',
  'glarea.c',
--- a/gsk/gl/gskglglyphcache.c
+++ b/gsk/gl/gskglglyphcache.c
@@ -28,6 +28,8 @@ typedef struct
 {
  PangoFont *font;
  PangoGlyph glyph;
+  guint xshift;
+  guint yshift;
  guint scale; /* times 1024 */
 } GlyphCacheKey;

@@ -120,6 +122,8 @@ glyph_cache_equal (gconstpointer v1, gconstpointer v2)

  return key1->font == key2->font &&
         key1->glyph == key2->glyph &&
+         key1->xshift == key2->xshift &&
+         key1->yshift == key2->yshift &&
         key1->scale == key2->scale;
 }

@@ -128,7 +132,7 @@ glyph_cache_hash (gconstpointer v)
 {
  const GlyphCacheKey *key = v;

-  return GPOINTER_TO_UINT (key->font) ^ key->glyph ^ key->scale;
+  return GPOINTER_TO_UINT (key->font) ^ key->glyph ^ (key->xshift << 24) ^ (key->yshift << 26) ^ key->scale;
 }

 static void
@@ -158,7 +162,7 @@ dirty_glyph_free (gpointer v)

 static void
 add_to_cache (GskGLGlyphCache  *cache,
-              GlyphCacheKey        *key,
+              GlyphCacheKey    *key,
              GskGLCachedGlyph *value)
 {
  GskGLGlyphAtlas *atlas;
@@ -262,10 +266,10 @@ render_glyph (const GskGLGlyphAtlas *atlas,
  glyph_info.glyph = key->glyph;
  glyph_info.geometry.width = value->draw_width * 1024;
  if (key->glyph & PANGO_GLYPH_UNKNOWN_FLAG)
-    glyph_info.geometry.x_offset = 0;
+    glyph_info.geometry.x_offset = key->xshift * 256;
  else
-    glyph_info.geometry.x_offset = - value->draw_x * 1024;
-  glyph_info.geometry.y_offset = - value->draw_y * 1024;
+    glyph_info.geometry.x_offset = key->xshift * 256 - value->draw_x * 1024;
+  glyph_info.geometry.y_offset = key->yshift * 256 - value->draw_y * 1024;

  glyph_string.num_glyphs = 1;
  glyph_string.glyphs = &glyph_info;
@@ -308,19 +312,30 @@ upload_dirty_glyphs (GskGLGlyphCache *self,
  atlas->dirty_glyphs = NULL;
 }

+#define PHASE(x) ((x % PANGO_SCALE) * 4 / PANGO_SCALE)
+
 const GskGLCachedGlyph *
-gsk_gl_glyph_cache_lookup (GskGLGlyphCache *cache,
-                           gboolean         create,
-                           PangoFont       *font,
-                           PangoGlyph       glyph,
-                           float            scale)
+gsk_gl_glyph_cache_lookup (GskGLGlyphCache       *cache,
+                           gboolean               create,
+                           PangoFont             *font,
+                           const PangoGlyph       glyph,
+                           int                    x,
+                           int                    y,
+                           float                  scale)
 {
  GskGLCachedGlyph *value;
+  guint xshift;
+  guint yshift;
+  
+  xshift = PHASE (x);
+  yshift = PHASE (y);

  value = g_hash_table_lookup (cache->hash_table,
                               &(GlyphCacheKey) {
                                 .font = font,
                                 .glyph = glyph,
+                                 .xshift = xshift,
+                                 .yshift = yshift,
                                 .scale = (guint)(scale * 1024)
                               });

@@ -357,6 +372,8 @@ gsk_gl_glyph_cache_lookup (GskGLGlyphCache *cache,

      key->font = g_object_ref (font);
      key->glyph = glyph;
+      key->xshift = xshift;
+      key->yshift = yshift;
      key->scale = (guint)(scale * 1024);

      if (ink_rect.width > 0 && ink_rect.height > 0)
--- a/gsk/gl/gskglglyphcacheprivate.h
+++ b/gsk/gl/gskglglyphcacheprivate.h
@@ -56,7 +56,9 @@ GskGLImage *             gsk_gl_glyph_cache_get_glyph_image (GskGLGlyphCache
 const GskGLCachedGlyph * gsk_gl_glyph_cache_lookup          (GskGLGlyphCache        *self,
                                                             gboolean                create,
                                                             PangoFont              *font,
-                                                             PangoGlyph              glyph,
+                                                             const PangoGlyph        glyph,
+                                                             int                     x,
+                                                             int                     y,
                                                             float                   scale);

 #endif
--- a/gsk/gl/gskglrenderer.c
+++ b/gsk/gl/gskglrenderer.c
@@ -417,14 +417,16 @@ render_text_node (GskGLRenderer   *self,
                                         TRUE,
                                         (PangoFont *)font,
                                         gi->glyph,
+                                         x_position + gi->geometry.x_offset,
+                                         gi->geometry.y_offset,
                                         text_scale);

      /* e.g. whitespace */
      if (glyph->draw_width <= 0 || glyph->draw_height <= 0)
        goto next;

-      cx = (double)(x_position + gi->geometry.x_offset) / PANGO_SCALE;
-      cy = (double)(gi->geometry.y_offset) / PANGO_SCALE;
+      cx = (x_position + gi->geometry.x_offset) / PANGO_SCALE;
+      cy = gi->geometry.y_offset / PANGO_SCALE;

      ops_set_texture (builder, gsk_gl_glyph_cache_get_glyph_image (&self->glyph_cache,
                                                                    glyph)->texture_id);
--- a/gsk/vulkan/gskvulkancolortextpipeline.c
+++ b/gsk/vulkan/gskvulkancolortextpipeline.c
@@ -120,12 +120,16 @@ gsk_vulkan_color_text_pipeline_collect_vertex_data (GskVulkanColorTextPipeline *

      if (gi->glyph != PANGO_GLYPH_EMPTY)
        {
-          double cx = (double)(x_position + gi->geometry.x_offset) / PANGO_SCALE;
-          double cy = (double)(gi->geometry.y_offset) / PANGO_SCALE;
+          double cx = (x_position + gi->geometry.x_offset) / PANGO_SCALE;
+          double cy = gi->geometry.y_offset / PANGO_SCALE;
          GskVulkanColorTextInstance *instance = &instances[count];
          GskVulkanCachedGlyph *glyph;

-          glyph = gsk_vulkan_renderer_get_cached_glyph (renderer, font, gi->glyph, scale);
+          glyph = gsk_vulkan_renderer_get_cached_glyph (renderer, font,
+                                                        gi->glyph,
+                                                        x_position + gi->geometry.x_offset,
+                                                        gi->geometry.y_offset,
+                                                        scale);

          instance->tex_rect[0] = glyph->tx;
          instance->tex_rect[1] = glyph->ty;
--- a/gsk/vulkan/gskvulkanglyphcache.c
+++ b/gsk/vulkan/gskvulkanglyphcache.c
@@ -115,6 +115,8 @@ gsk_vulkan_glyph_cache_class_init (GskVulkanGlyphCacheClass *klass)
 typedef struct {
  PangoFont *font;
  PangoGlyph glyph;
+  guint xshift;
+  guint yshift;
  guint scale; /* times 1024 */
 } GlyphCacheKey;

@@ -126,6 +128,8 @@ glyph_cache_equal (gconstpointer v1, gconstpointer v2)

  return key1->font == key2->font &&
         key1->glyph == key2->glyph &&
+         key1->xshift == key2->xshift &&
+         key1->yshift == key2->yshift &&
         key1->scale == key2->scale;
 }

@@ -134,7 +138,7 @@ glyph_cache_hash (gconstpointer v)
 {
  const GlyphCacheKey *key = v;

-  return GPOINTER_TO_UINT (key->font) ^ key->glyph ^ key->scale;
+  return GPOINTER_TO_UINT (key->font) ^ key->glyph ^ (key->xshift << 24) ^ (key->yshift << 26) ^ key->scale;
 }

 static void
@@ -267,10 +271,10 @@ render_glyph (Atlas          *atlas,
  gi.glyph = key->glyph;
  gi.geometry.width = value->draw_width * 1024;
  if (key->glyph & PANGO_GLYPH_UNKNOWN_FLAG)
-    gi.geometry.x_offset = 0;
+    gi.geometry.x_offset = key->xshift * 256;
  else
-    gi.geometry.x_offset = - value->draw_x * 1024;
-  gi.geometry.y_offset = - value->draw_y * 1024;
+    gi.geometry.x_offset = key->xshift * 256 - value->draw_x * 1024;
+  gi.geometry.y_offset = key->yshift * 256 - value->draw_y * 1024;

  glyphs.num_glyphs = 1;
  glyphs.glyphs = &gi;
@@ -328,18 +332,29 @@ gsk_vulkan_glyph_cache_new (GskRenderer      *renderer,
  return cache;
 }

+#define PHASE(x) ((x % PANGO_SCALE) * 4 / PANGO_SCALE)
+
 GskVulkanCachedGlyph *
 gsk_vulkan_glyph_cache_lookup (GskVulkanGlyphCache *cache,
                               gboolean             create,
                               PangoFont           *font,
                               PangoGlyph           glyph,
+                               int                  x,
+                               int                  y,
                               float                scale)
 {
  GlyphCacheKey lookup_key;
  GskVulkanCachedGlyph *value;
+  guint xshift;
+  guint yshift;
+
+  xshift = PHASE (x);
+  yshift = PHASE (y);

  lookup_key.font = font;
  lookup_key.glyph = glyph;
+  lookup_key.xshift = xshift;
+  lookup_key.yshift = yshift;
  lookup_key.scale = (guint)(scale * 1024);

  value = g_hash_table_lookup (cache->hash_table, &lookup_key);
@@ -374,6 +389,8 @@ gsk_vulkan_glyph_cache_lookup (GskVulkanGlyphCache *cache,

      key->font = g_object_ref (font);
      key->glyph = glyph;
+      key->xshift = xshift;
+      key->yshift = yshift;
      key->scale = (guint)(scale * 1024);

      if (ink_rect.width > 0 && ink_rect.height > 0)
--- a/gsk/vulkan/gskvulkanglyphcacheprivate.h
+++ b/gsk/vulkan/gskvulkanglyphcacheprivate.h
@@ -22,6 +22,8 @@ GskVulkanCachedGlyph *gsk_vulkan_glyph_cache_lookup         (GskVulkanGlyphCache
                                                             gboolean             create,
                                                             PangoFont           *font,
                                                             PangoGlyph           glyph,
+                                                             int                  x,
+                                                             int                  y,
                                                             float                scale);

 void                  gsk_vulkan_glyph_cache_begin_frame    (GskVulkanGlyphCache *cache);
--- a/gsk/vulkan/gskvulkanrenderer.c
+++ b/gsk/vulkan/gskvulkanrenderer.c
@@ -339,15 +339,6 @@ gsk_vulkan_renderer_ref_texture_image (GskVulkanRenderer *self,
  return image;
 }

-guint
-gsk_vulkan_renderer_cache_glyph (GskVulkanRenderer *self,
-                                 PangoFont         *font,
-                                 PangoGlyph         glyph,
-                                 float              scale)
-{
-  return gsk_vulkan_glyph_cache_lookup (self->glyph_cache, TRUE, font, glyph, scale)->texture_index;
-}
-
 GskVulkanImage *
 gsk_vulkan_renderer_ref_glyph_image (GskVulkanRenderer  *self,
                                     GskVulkanUploader  *uploader,
@@ -356,11 +347,24 @@ gsk_vulkan_renderer_ref_glyph_image (GskVulkanRenderer  *self,
  return g_object_ref (gsk_vulkan_glyph_cache_get_glyph_image (self->glyph_cache, uploader, index));
 }

+guint
+gsk_vulkan_renderer_cache_glyph (GskVulkanRenderer *self,
+                                 PangoFont         *font,
+                                 PangoGlyph         glyph,
+                                 int                x,
+                                 int                y,
+                                 float              scale)
+{
+  return gsk_vulkan_glyph_cache_lookup (self->glyph_cache, TRUE, font, glyph, x, y, scale)->texture_index;
+}
+
 GskVulkanCachedGlyph *
 gsk_vulkan_renderer_get_cached_glyph (GskVulkanRenderer *self,
                                      PangoFont         *font,
                                      PangoGlyph         glyph,
+                                      int                x,
+                                      int                y,
                                      float              scale)
 {
-  return gsk_vulkan_glyph_cache_lookup (self->glyph_cache, FALSE, font, glyph, scale);
+  return gsk_vulkan_glyph_cache_lookup (self->glyph_cache, FALSE, font, glyph, x, y, scale);
 }
--- a/gsk/vulkan/gskvulkanrendererprivate.h
+++ b/gsk/vulkan/gskvulkanrendererprivate.h
@@ -45,6 +45,8 @@ typedef struct
 guint                  gsk_vulkan_renderer_cache_glyph      (GskVulkanRenderer *renderer,
                                                             PangoFont         *font,
                                                             PangoGlyph         glyph,
+                                                             int                x,
+                                                             int                y,
                                                             float              scale);

 GskVulkanImage *       gsk_vulkan_renderer_ref_glyph_image  (GskVulkanRenderer *self,
@@ -54,6 +56,8 @@ GskVulkanImage *       gsk_vulkan_renderer_ref_glyph_image  (GskVulkanRenderer *
 GskVulkanCachedGlyph * gsk_vulkan_renderer_get_cached_glyph (GskVulkanRenderer *self,
                                                             PangoFont         *font,
                                                             PangoGlyph         glyph,
+                                                             int                x,
+                                                             int                y,
                                                             float              scale);


--- a/gsk/vulkan/gskvulkanrenderpass.c
+++ b/gsk/vulkan/gskvulkanrenderpass.c
@@ -369,6 +369,7 @@ gsk_vulkan_render_pass_add_node (GskVulkanRenderPass           *self,
        int i;
        guint count;
        guint texture_index;
+        gint x_position;
        GskVulkanRenderer *renderer = GSK_VULKAN_RENDERER (gsk_vulkan_render_get_renderer (render));

        if (font_has_color_glyphs (font))
@@ -401,11 +402,17 @@ gsk_vulkan_render_pass_add_node (GskVulkanRenderPass           *self,
        op.text.texture_index = G_MAXUINT;
        op.text.scale = self->scale_factor;

+        x_position = 0;
        for (i = 0, count = 0; i < num_glyphs; i++)
          {
            const PangoGlyphInfo *gi = &glyphs[i];

-            texture_index = gsk_vulkan_renderer_cache_glyph (renderer, (PangoFont *)font, gi->glyph, op.text.scale);
+            texture_index = gsk_vulkan_renderer_cache_glyph (renderer,
+                                                             (PangoFont *)font,
+                                                             gi->glyph,
+                                                             x_position + gi->geometry.x_offset,
+                                                             gi->geometry.y_offset,
+                                                             op.text.scale);
            if (op.text.texture_index == G_MAXUINT)
              op.text.texture_index = texture_index;
            if (texture_index != op.text.texture_index)
@@ -420,6 +427,8 @@ gsk_vulkan_render_pass_add_node (GskVulkanRenderPass           *self,
              }
            else
              count++;
+
+            x_position += gi->geometry.width;
          }

        if (op.text.texture_index != G_MAXUINT && count != 0)
--- a/gsk/vulkan/gskvulkantextpipeline.c
+++ b/gsk/vulkan/gskvulkantextpipeline.c
@@ -128,12 +128,17 @@ gsk_vulkan_text_pipeline_collect_vertex_data (GskVulkanTextPipeline  *pipeline,

      if (gi->glyph != PANGO_GLYPH_EMPTY)
        {
-          double cx = (double)(x_position + gi->geometry.x_offset) / PANGO_SCALE;
-          double cy = (double)(gi->geometry.y_offset) / PANGO_SCALE;
+          double cx = (x_position + gi->geometry.x_offset) / PANGO_SCALE;
+          double cy = gi->geometry.y_offset / PANGO_SCALE;
          GskVulkanTextInstance *instance = &instances[count];
          GskVulkanCachedGlyph *glyph;

-          glyph = gsk_vulkan_renderer_get_cached_glyph (renderer, font, gi->glyph, scale);
+          glyph = gsk_vulkan_renderer_get_cached_glyph (renderer,
+                                                        font,
+                                                        gi->glyph,
+                                                        x_position + gi->geometry.x_offset,
+                                                        gi->geometry.y_offset,
+                                                        scale);

          instance->tex_rect[0] = glyph->tx;
          instance->tex_rect[1] = glyph->ty;
--- a/gtk/gtksettings.c
+++ b/gtk/gtksettings.c
@@ -2080,7 +2080,7 @@ settings_update_font_options (GtkSettings *settings)

  priv->font_options = cairo_font_options_create ();

-  cairo_font_options_set_hint_metrics (priv->font_options, CAIRO_HINT_METRICS_ON);
+  cairo_font_options_set_hint_metrics (priv->font_options, CAIRO_HINT_METRICS_OFF);

  hint_style = CAIRO_HINT_STYLE_DEFAULT;
  if (hinting == 0)
Author	SHA1	Message	Date
Matthias Clasen	e00d393b6a	vulkan: implement subpixel positioning Pass the glyph position into the glyph caching functions, not just the glyph index. This allows us to cache different images for different subpixel positions.	2018-07-28 22:34:05 -04:00
Matthias Clasen	4a87115763	gl: implement subpixel positioning Pass the glyph position into the glyph caching functions, not just the glyph index. This allows us to cache different images for different subpixel positions.	2018-07-28 21:34:37 -04:00
Matthias Clasen	273d60fefa	Turn off metrics hinting This will be necessary to see the effects of subpixel positioning.	2018-07-28 21:34:37 -04:00
Matthias Clasen	e781f986f7	Sync with improvements in the gtk3 version Add a grid which shows subpixel phases.	2018-07-28 11:34:28 -04:00
Matthias Clasen	40b90a16ab	Add a font rendering demo This renders a magnified version of the text, to make the effect of various font rendering options more visible.	2018-07-27 18:42:22 -04:00