I'm a bit confused as the powervrs are claming zero-overdraw. If this is true, the chip has to operate on per-pixel level instead of per-quad level that's pretty much standard for years. And according to the configuration, some powerVR seems using 2 pixel shaders/TMUs which does not seem natural for a quad based renderer.
So it's possible that only one fragment survives the depth testing. In this case, only interpolated attributes have well-defined ddx/ddy, other non-linear function are probably not. For example, the mip-map level calculation of a dependant texture fetch.
Can someone shed a light on this?
So it's possible that only one fragment survives the depth testing. In this case, only interpolated attributes have well-defined ddx/ddy, other non-linear function are probably not. For example, the mip-map level calculation of a dependant texture fetch.
Can someone shed a light on this?