AMD Ray Tracing/Path Tracing Thread -

[shankly1985]

I wanted to post this video I found on the AMD Reddit but wasn't sure where I wanted to post it.
I created an AMD Ray Tracing discussion thread to talk about the future and even present ray tracing information.
MineCraft seems to be working so far on the patreon version of the mod. Running on a 480 and getting to my surprise ok FPS for what its worth. Would be nice to see maybe a VEGA or Navi running this.

 

[Grim5]

17fps lows, but whats your resolution?

 

[shankly1985]

17fps lows, but whats your resolution?

It's not my video so I not sure.

 

[shankly1985]

Not sure what the resolution is here but in the brief moments he/she shows the FPS counter it is running around 17fps not ideal like. Also, I should add to the title this isn't Ray Tracing its Path Tracing and is the reason this is working on AMD.

RX 580

For comparision, 2060 is getting around 45/30 fps again though I do know the in-game resolution.

 

[shankly1985]

5700XT playable frame rates with Ray Tracing on Minecraft 40/60 fps

 

[Grim5]

It's playable, but even so it looks like it droped into the 20s a few times

 

[shankly1985]

It's playable, but even so it looks like it droped into the 20s a few times

5700xt doesn't drop below 35fps in his run. Its the water part that is the most demanding 35/45fps away from the water 40/60fps

Edit
even with the texture pack it doesn't drop below 30fps

 

[Grim5]

5700xt doesn't drop below 35fps in his run. Its the water part that is the most demanding 35/45fps away from the water 40/60fps

Edit
even with the texture pack it doesn't drop below 30fps

Sorry I should have clarified. Towards the end of the video there are parts where he doesn't have any fps counter and the screen starts lagging crazy

 

[shankly1985]

Sorry I should have clarified. Towards the end of the video there are parts where he doesn't have any fps counter and the screen starts lagging crazy

That's on a 580 it's hard to really say without a frame counter

 

[Gregster]

Good to see AMD jumping on RT. Hopefully both get better at it, as it is superb when done well

 

[D1craig]

Whats the difference between ray and path tracing?

 

[shankly1985]

Whats the difference between ray and path tracing?

Not sure I do know Minecraft is using path tracing though.

 

[Rroff]

Whats the difference between ray and path tracing?

They are both forms of ray tracing. Path tracing is kind of like a scattergun approach - imagine firing a load of shot at a point on the screen and just letting each pellet bounce off and see where it goes randomly then use the results to build a sample of how that point is lit in the scene - usually in a game the data would be gathered over a few frames which can result in artefacts but that will improve - it also means the results are quite noisy as each time you use that scattergun sample the results will be very slightly different due to the random nature of it so various techniques have to be used to get consistent results. Traditional ray tracing you'd find each point in a scene then test it with a direct line between it and known light sources and it is much harder to do indirect light and soft shadows though most ray tracers used a variety of techniques so as to be able to do those kind of features.

 

[D1craig]

I don’t understand how it’s so difficult to put a sun in a scene before anything else is put in and then stick everything else in afterwards so the shadows are not so hard to produce because the will be made right away. To me it seems a lot more difficult for it to be done the old way...

 

[Rroff]

I don’t understand how it’s so difficult to put a sun in a scene before anything else is put in and then stick everything else in afterwards so the shadows are not so hard to produce because the will be made right away. To me it seems a lot more difficult for it to be done the old way...

I'm not quite sure what you are saying there but shadows in games are done completely different to what I think you are saying it is a bit hard to explain but normally in a game lights don't cast shadows from objects they merely brighten the side of an object facing the light - objects are special cased to cast a shadow as if from the light that is illuminating the scene - usually by some form of copying a 2D map of the object into a texture and then projecting it into the scene. This is why ray tracing (or some form of it) will eventually transform games.

 

[D1craig]

Most games I’ve played in the last few years have had shadows and a day cycle, I can’t say I remember the shadows staying still while the day progressed.

Ok so wouldn’t it be less got constrained to do it the way I said and add a light source first then add all the objects? Is making a realistic light source so difficult for the god to handle? I’m not even the slightest bit a coder so I’ve no idea.

 

[Rroff]

Most games I’ve played in the last few years have had shadows and a day cycle, I can’t say I remember the shadows staying still while the day progressed.

Ok so wouldn’t it be less got constrained to do it the way I said and add a light source first then add all the objects? Is making a realistic light source so difficult for the god to handle? I’m not even the slightest bit a coder so I’ve no idea.

Traditionally lights in a video game don't cast shadows - you stick a light (sun) in and then some objects and all that would happen is the side of the objects facing the sun are illuminated based on distance and the falloff type of the light you get no shadows at all and even if one object is between the light and another object it doesn't stop the one behind being illuminated. Shadows are then processed separately and tacked on using a variety of shadow mapping (using a copy of the object projected into or projected as a texture of some form) or stencil techniques (projecting a copy of the polygons of an object and clipping them to the scene).