Fix heap corruption with smaller mipmaps due to decompression output
always being a 4x4 block rather than actual mipmap size. It's necessary to
pad the allocated data size to allow for the overflow.
Fix heap corruption with DXT1 due to using improper data offsets for the type.
Fix data offsets not always taking the depth value into account.
Adjust code for slight increase in decode performance.
Update bcdec to 0.98
Adds bcdec lib to convert compressed DDS textures to RGBA based on what the
system supports. BC7 if BPTC extension not supported, DXT? if S3TC extension
not supported.
Should support cubemaps and volume textures but those were not tested.
Addtional changes:
- remove indexed DDS support since it had bugs but didn't work anyway
(R8 should be used instead)
- fix issues with volume textures (nothing to test with)
- remove old compression support flags as they are now obsolete
Fixes#4920
Taylor Richards