Too high GPU times on https://www.newegg.com/pc-build-kits

[mstange]

Scrolling around in the middle part of https://www.newegg.com/pc-build-kits is not 60fps on macOS in a very large Firefox window on my external HiDPI 5k screen.

[glennw]

The main point that shows up in the profile is the amount of overdraw.

The opaque pass is around 1.22x while the transparent pass is ~2.5x overdraw.

One way that I've been thinking about to deal with this is to ensure we cache pictures that end up having several translucent overlays, so that they are pre-rendered into a surface and we only have to draw them once into the main scene.

I'll need to do some more investigation and find out exactly why the overdraw is that high.

[kvark]

I looked a bit at the GPU capture:

• there are a few full-screen-ish items that get (mostly) depth culled. This is fine by itself, but only within the assumption that the driver is able to enable the early depth test (which, for example, is not the case for some drivers when shaders use "discard" instruction). Thus, we need to get some IHV-specific profiling tools to expose this info and confirm (RenderDoc can't do this). Particular shaders I noticed used for those passes in this case are : Image, YuvImage, Blend
• Some of the border corners are giant, and we could benefit from a more detailed tessellation (into opaque/transparent parts)

Note: I don't quite understand yet how the transparent pass reaches 2.5x overdraw. As I mentioned, most of the pixels appear to be depth culled.