"Motion blur" - LCD persistence shader

[iota97]

Well, should help testing if we broke it at least, 2008 feels...

[hrydgard]

It's not really motion blur (that requires motion vectors), more like image persistence or slow LCD. So maybe just call it "LCD simulation"? :)

Although it is true that back in the PS2 days, people did call this kind of thing motion blur.

[hrydgard]

Good test case, I'll merge when PPSSPP has been fixed so it works :)

[hrydgard]

Just tried it on Vulkan, seems to work perfectly fine when alone or last in the list. Other positions ... not so much :) For example, try putting it before Bloom.

Not sure if we should simply regulate where it can appear, or fix it somehow...

[jcchikikomori]

Best test scenario for this is Tekken 6. I attempt to fake the motion blur experience with the PS3 & the Arcade machines, including this texture pack. It's almost 1:1 with the PS3 but HD

https://github.com/kharij/Tekken-6-HD-Texture-Pack

[jcchikikomori]

It's not really motion blur (that requires motion vectors), more like image persistence or slow LCD. So maybe just call it "LCD simulation"? :)

Although it is true that back in the PS2 days, people did call this kind of thing motion blur.

That's what it calls like huh.. I called it the "motion blur" way back in my childish days, but not confidently when Crysis came out with the actual motion blur

[iota97]

I really thought I had tested Vulkan too, my bad.

Anyway Vulkan works fine, OpenGL was broken in: bd674c4.

The previous frame is in sampler2, and get pushed to queries:

ppsspp/Common/GPU/OpenGL/thin3d_gl.cpp

Line 1248 in b06ea97

queries.push_back({ &samplerLocs_[2], "sampler2" });

After that commit the check is on samplers_ rather than queries (reverting just this change on the commit fix it):

ppsspp/Common/GPU/OpenGL/thin3d_gl.cpp

Line 1257 in b06ea97

if (i < (int)samplers_.size()) {

I have no idea why this was changed, so I'll leave the fix to you :)

[hrydgard]

Oh interesting, I'll fix it up.

And, I think I will simply enforce that this type of shader lives at the end of the shader list, and only one is allowed. Not gonna make very nice UI for it, it'll just be forced for now.

[hrydgard]

I'm replacing this PR with #16531, which includes the commits from this one.