[PATCH v2 2/4] windowscodecs/tests: Add a DXT3 test image for DDS decoder.

[Ziqing Hui]

We only tested DXT1 images with 1 blocks before. That's not enough.

Also, for CopyBlocks(), when boundsInBlocks parameter is NULL, the stride should be the stride of the frame itself.

Signed-off-by: Ziqing Hui <zhui(a)codeweavers.com>
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 dlls/windowscodecs/tests/ddsformat.c | 67 ++++++++++++++++++++++++----
 1 file changed, 59 insertions(+), 8 deletions(-)