This is a fix for issue #15944, and handles corner cases in the FrameBuffer
code when using stride values where the last line's stride may extend past
the end of the underlying buffer. This commit includes extra tests for
these corner cases.
For example a GS8 format FrameBuffer with a width of 8, height of 2 and
stride of 10 should be able to fit into a buffer of size 18 (10 bytes for
the first horizontal line, and 8 bytes for the second -- the full 10 bytes
are not needed).
Similarly a 1 by 9 FrameBuffer in MONO_VLSB format with a stride of 10
should be able to fit into a buffer of length 11 (10 bytes for the first
8 lines, and then one byte for the 9th line.
Being able to do this is particularly important when cropping the corner of
an existing FrameBuffer, either to copy a sprite or to clip drawing.
Signed-off-by: Corran Webster <cwebster@unital.dev>
This ensures that the buffer is large enough for the specified width,
height, bits-per-pixel, and stride.
Also makes the legacy FrameBuffer1 constructor re-use the FrameBuffer
make_new to save some code size.
Fixes issue #12562.
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
