ULES00126 Virtua Tennis: World Tour - Start Menu not showing properly in some backends

[ppmeis]

Platform: Windows 10 x64 October 2018 Update
Hardware: i7 3770K/Nvidia GTX 1080
PPSSPP Build: Latest

Start a normal match, after game is loaded press start. No start menu in Vulkan and Direct3D11.

Tested with latest build. Lightning seems to be fine thanks to latest changes, but now start menu has disappeared in some backends:

Vulkan:

ULES00126_0001.zip

OpenGL seems to be fine:

Direct3D9:

Direct3D11:

ULES00126_0002.zip

Originally posted by @ppmeis in #4140 (comment)

[hrydgard]

Is it really new that the pause menu disappears? If so, could you try to find the build where it happens?

[ppmeis]

Tested previous builds, this bug is present since v1.5.4:

• v1.5.4-189-gc1a23658d working fine:
  
  ULES00126_0001.zip

• v1.5.4-197-gea50561c8 fail
  
  ULES00126_0001.zip

[hrydgard]

It sounded like it was new when you said "but now start menu has disappeared in some backends:".

Very low-impact, pushing back to 1.9.

[unknownbrackets]

Copying this here from #4140:

Near texture 0x08973d00 + several draws to VAIDISOVA. I think that's a separate issue related to depth.

It draws verts with a crazy high Z, depth clamp, and standard minz/maxz. It uses src >= depth test. This passes and it draws the BG and clamped depth. Lighting is disabled. Alpha test and blend, but 8c alpha sent.

Not clear what should be keeping it from drawing... it doesn't draw on a PSP running the same dump...

The range implies allowing depth clamp was the cause, but I'm just not sure why it SHOULDN'T clamp in this case:
v1.5.4-189-gc1a23658d...v1.5.4-197-gea50561c8

-[Unknown]

[ppmeis]

Tested with latest build, same issues. Also I saw a new render error after a point:

It should show both players

ULES00126_0001.zip

[meowthed]

Issue still present as of 1.9.3 on Vulkan backend

[ppmeis]

Tested in latest Windows build. Same issues.

[hrydgard]

I think that dark overlay with a way-out-of-range depth value is a remnant from the Dreamcast version, and nobody simply noticed that it wasn't rendering on the PSP. The Dreamcast notoriously had full FP32 depth and depth sorting! (early PowerVR took the tricks you can do with tile-based rendering very far).

That said, why we are clamping and the PSP is not is unclear. This only "works" right now in D3D9 and GLES because we don't do depth clamping.

[hrydgard]

Anyway, this has such small impact that I'm postponing the investigation to after 1.10.

[unknownbrackets]

It should show both players

This is caused by draw 481. As far as I can tell, it's caused by some verts with depth very negative not being clamped, as per notes in #12058. It works in softgpu with those rules implemented.

v1.5.4-197-gea50561c8 fail

This is 621/639. In this case, it's definitely negative Z, the initial Z is positive, but the projection matrix reverses it (just to be reversed again by the viewport.) This draw should just be clipped. I wonder if they initially intended to gray the screen, but it didn't work and they just left it rather than debug since it looked fine not grayed.

Both seem like they'll be fixed by implementing the Z rules noted in #12058.

-[Unknown]