Do any Doom ports support Ambient Occlusion?

If no, is there a technical reason to make this impossible/severely hard?

GZDoom does.

1 minute ago, Nevander said:

GZDoom does.

Right'o, thanks! Not a huge fan of the blur in the GL ports, I kinda like the hard edged pixels, but I guess they might be incompatible with ambient occlusion...

1 minute ago, Soundblock said:

 

Right'o, thanks! Not a huge fan of the blur in the GL ports, I kinda like the hard edged pixels, but I guess they might be incompatible with ambient occlusion...

You can turn texture filtering (the blur) off in texture settings.  Set it to "nearest" for your nice, crunchy pixels :)

Texture filtering is completely optional and separate, as far as I know anyway. I can't use AO without lag so I keep it off. But I do know you can have crisp pixels.

Alright, I'll play around with some settings next time I boot it up, thx guys. Been a while and last time I believe I used ZDoom.

It's been years since I used the port but I'm pretty sure Doomsday has this too.

I have thought about coding it in EDGE, we will see what happens :)

Does GZDoom still just have the basic SSAO effect? That has always kind of bugged me to use because the level geometry is so simple that it's really easy to notice how it disappears near the screen boundary, and has weird effects at certain angles, etc. I would love to see a Doom port implement a more complex algorithm like HBAO, or even using a voxel-based system like VXAO or path tracing or whatever.

On 17/4/2018 at 9:51 PM, Eric the Sandvich said:

If that's true, I'd be pissed to find that something as simple as rendering SSAO on Doom level geometry taking up 40% more GPU usage on a GTX 1080 Ti.

 

Although I'm fairly certain something else is causing that...

I play GZDoom with AO enabled with little perfomance impact on an R7 250. It's hard to believe you'd have such an impact on a 1080.

On 4/18/2018 at 3:42 AM, Linguica said:

Does GZDoom still just have the basic SSAO effect? That has always kind of bugged me to use because the level geometry is so simple that it's really easy to notice how it disappears near the screen boundary, and has weird effects at certain angles, etc. I would love to see a Doom port implement a more complex algorithm like HBAO, or even using a voxel-based system like VXAO or path tracing or whatever.

The SSAO pass in GZDoom is a HBAO variant (newer than original HBAO, can't recall the name of the paper it is based on right now). It is called SSAO since there's been so many variants of screen space AO since the original depth-only SSAO algorithm. As a result, most newer games don't try to name the specific algorithm. The near screen boundary artifact is an inherent limitation of screen space AO as it cannot sample depth information outside the rendered canvas. Theoretically, the effect could be reduced a bit by rendering more than just the visual screen, but that comes at a performance cost.

By the way, the level complexity has no impact on the cost of a screen-space algorithm.

Based on my limited experience, different graphics cards seem to cope with GZDoom's AO differently. On my old integrated laptop AO would cause a big hit to FPS, but my new 1060 powered laptop doesn't even seem to notice it.