   On 2010-05-20 18:23, Gregg Tavares wrote:  On Thu, May 20,
2010 at 8:53 AM, Chris Marrin <cmarrin@apple.com
<mailto:cmarrin@apple.com>> wrote:  On May 19, 2010, at 7:40 PM,
Gregg Tavares wrote:      > ...     > What I don't get is why
the need for these conversions? If you     load a grayscale
image as RGB you'll get the same visual result as     LUMINANCE.
So it seems like the valid reason to do these     conversions is
for memory savings since you can always create RGB     or RGBA
textures that will give you the same visual result.      I don't
see how loading a grayscale as RGB is the same as     LUMINANCE.
The OpenGL texturing engine deals with LUMINANCE     textures
differently from RGB. The problem the information that an
original image was one channel is lost in the browser
implementations. Even if not (if the browsers were forced to
pass     along the original image format information)
implementations would     have to have internal format
conversion to get the image into the     right form