Re: Non-RGBA Texture Storage

On Oct 26, 4:45 pm, crjjrc <crj...@xxxxxxxxx> wrote:
The red book states that some implementations perform faster with
GL_RGBA over GL_RGB thanks to better memory alignment. This suggests
to me that implementations that perform worse do not store the
implicit alpha of 1.0 for GL_RGB textures (otherwise the memory
alignment would be the same). Is this interpretation correct?

Yup. It means internally 8 bits are reserved/undefined and just place
holder for alignment. "pure" 24 bit internal format will save storage
space but means the memory arbiter will be more complicated and there
will be always some extra traffic, etc.. aligned is less hassle.

.

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