Quoting Chris Wilson (2017-07-31 22:51:25) > Luminance/Intensity when converted to RGB should be replicated to fill > the RGB channels, but they differ on how the alpha channel is filled, as > luminance is set to 1 (unless alpha is supplied) and intensity is > replicated into alpha as well. > > https://www.khronos.org/opengl/wiki/Image_Format: > > Legacy Image Formats > > Warning: This section describes legacy OpenGL APIs that have been > removed from core OpenGL 3.1 and above (they are only deprecated in > OpenGL 3.0). It is recommended that you not use this functionality in > your programs. > > As with other deprecated functionality, it is advised that you not rely > on these features. > > Luminance and intensity formats are color formats. They are one or two > channel formats like RED or RG, but they specify particular behavior. > > When a GL_RED format is sampled in a shader, the resulting vec4 is (Red, > 0, 0, 1). When a GL_INTENSITY format is sampled, the resulting vec4 is > (I, I, I, I). The single intensity value is read into all four > components. For GL_LUMINANCE, the result is (L, L, L, 1). There is also > a two-channel GL_LUMINANCE_ALPHA format, which gives (L, L, L, A). > > v2: luminance -> xxx1, intensity -> xxxx, luminance_alpha -> xxxw
If that quote is the expected behaviour for glReadPixels and glGetTexSubImage, there's a similar stanza to fix in texgetimage.c (As well as the piglit tests to update.) With a quick grep through VK-GL-CTS I didn't anything to refer to. -Chris _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
