Hi,
I am working on a linux (directfb/fbdev) port of chromium on a set top box platform which has a Mali-400 GPU.
I have an issue with an HTML application creating a webgl context in RGB (without alpha).
After analysis, we can see that chromium creates a frame buffer object, and tries to attach a texture via glFramebufferTexture2D. When checking the status via glCheckFramebufferStatus, we get the error GL_FRAMEBUFFER_UNSUPPORTED. This issue happens only if the color buffer is in format GL_RGB. There is no issue if the format is GL_RGBA.
it seems that the Mali-400 opengl implementation does not support RGB texture as a frame buffer attachment. Is it the case?
Thanks&Regards,
Lidwine
Is this behavior present on all types of Mali GPU/drivers versions?
All of the Mali-2/3/400 family. The newer Mali-T600/700/800 families support it (however, note that 24-bit surfaces are generally significantly less efficient than 32-bit surfaces, as they are a power of two, therefore do not align neatly on power of two address boundaries)
Are there any plan for an update to support RGB?
No.
HTH,
Pete