Imagination PowerVR SDK Blog

minimum values for mipmap dimensions


#1

I see there are 2 constants for minimum mipmap sizes:
PVRTC2_MIN_TEXWIDTH        = 16;
PVRTC2_MIN_TEXHEIGHT        = 8;
The fact that these two are different means that mipmaps won’t work on iPhone, because glCompressedTexImage2D fails if the texture isn’t square (that’s a limitation on iPhone).
Any suggestions how to work around this issue?



#2

These are the minimum sizes for calculating the data size of each mipmap level. They do not affect the width and height parameters passed to glCompressedTexImage2D.





In other words, mipmaps of 8x8 and below will all have a data size of 32 bytes.


#3

Oh yeah, now I see Tongue. Thanks for the quick answer.