Picking through our GL call traces for more PowerVR optimization ideas, I noticed that we are using scissor rectangles for viewports (GL_SCISSOR_TEST). I see that in one of the PowerVR docs, it recommends that developers prefer stencil to scissor (assuming one is really required) as it is performed completely on-chip.
Is this recommendation still recommended for PowerVR Series 6 GPUs? Or is this an old Series 5/SGX tip?
Also on Series 6, is this implemented with an internal fragment shader modification or with fixed-function hardware?