Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Announcing Microsoft DirectX Raytracing

blogs.msdn.microsoft.com

Post reply on HN
Print view View original

11–20 of 235 posts

Re: Announcing Microsoft DirectX Raytracing

#11

Post by bhouston »

binarycrusader wrote: post #9
bhouston wrote: post #7

The only issue is that a lot of this is already possible in the current renderers at a reduced cost. - Soft shadows work in WebGL fairly well using PCSS: https://clara.io/player/v2/8f49e7c3-7c5e-43f0-a09c-33a55bb1b... - Translucency can be faked effectively using a few different methods. https://clara.io/view/5c7d28c0-91d7-4432-a131-3e6fd657a042 - Screen space ambient occlusion, if using SAO, is amazing. SAO test: ht…

Maybe, but it may make it substantially more accessible and easier for the average developer that isn't a domain expert in a dozen areas of graphics rendering technology and doesn't want to use a pre-built engine.

This will make it easier to port existing shaders from high end VFX to real-time, like RenderMan and OSL shaders for sure. Trivial even.

Re: Announcing Microsoft DirectX Raytracing

#13

Post by bhouston »

mnw21cam wrote: post #6

> From each light source within a scene, rays of light are projected, bouncing around until they strike the camera. Which is definitely not how raytracing is done if you want to get an image before the end of the world occurs. Rays are traced from the camera, and then back to the light sources. Some amount of pre-lighting can be done by tracing photons forwards from lights, but not the main image generation.

In path tracing (https://en.wikipedia.org/wiki/Path_tracing), which is what the VFX industry uses primarily, both directions happen.

Re: Announcing Microsoft DirectX Raytracing

#15

Post by oh_sigh »

bhouston wrote: post #13
mnw21cam wrote: post #6

> From each light source within a scene, rays of light are projected, bouncing around until they strike the camera. Which is definitely not how raytracing is done if you want to get an image before the end of the world occurs. Rays are traced from the camera, and then back to the light sources. Some amount of pre-lighting can be done by tracing photons forwards from lights, but not the main image generation.

In path tracing ( https://en.wikipedia.org/wiki/Path_tracing ), which is what the VFX industry uses primarily, both directions happen.

Does anyone use path tracing for live renderings? I think that is the question.

Re: Announcing Microsoft DirectX Raytracing

#16

Post by zdfjkhiuj »

bhouston wrote: post #7

The only issue is that a lot of this is already possible in the current renderers at a reduced cost. - Soft shadows work in WebGL fairly well using PCSS: https://clara.io/player/v2/8f49e7c3-7c5e-43f0-a09c-33a55bb1b... - Translucency can be faked effectively using a few different methods. https://clara.io/view/5c7d28c0-91d7-4432-a131-3e6fd657a042 - Screen space ambient occlusion, if using SAO, is amazing. SAO test: ht…

I'm not sure it's fair to describe those as hacks. Those techniques are also used for animated movies, which take many CPU-years to render. Those "hacks" are used even when artist have huge amounts of hardware, no real-time constraints, and need extremely high quality.

Techniques other than raytracing have an artistic place, not merely a pragmatic one.

Re: Announcing Microsoft DirectX Raytracing

#17

Post by jasonwatkinspdx »

bhouston wrote: post #7

The only issue is that a lot of this is already possible in the current renderers at a reduced cost. - Soft shadows work in WebGL fairly well using PCSS: https://clara.io/player/v2/8f49e7c3-7c5e-43f0-a09c-33a55bb1b... - Translucency can be faked effectively using a few different methods. https://clara.io/view/5c7d28c0-91d7-4432-a131-3e6fd657a042 - Screen space ambient occlusion, if using SAO, is amazing. SAO test: ht…

While the above is accurrate I think it's a bit one sided.

Physically Based Rendering has become the dominant approach in VFX because it's a huge simplification and productivity boost. Integrating tons of special purpose hacks into one renderer isn't just hard for the renderer devs, the control parameters exposed to artists become an absolute nightmare. Combing the PBR perspective with raytracing greatly simplifies both sides of this.

Not every game is trying to be the next Far Cry. Ray tracing will be adopted by teams that value that unification and simplification over getting the very last bit of performance possible by a pile of hacks. As the hardware improves, which still seems likely, we'll see the balance point of who makes that call shift in favor of tracing IMO.

Re: Announcing Microsoft DirectX Raytracing

#18

Post by digi_owl »

bhouston wrote: post #7

The only issue is that a lot of this is already possible in the current renderers at a reduced cost. - Soft shadows work in WebGL fairly well using PCSS: https://clara.io/player/v2/8f49e7c3-7c5e-43f0-a09c-33a55bb1b... - Translucency can be faked effectively using a few different methods. https://clara.io/view/5c7d28c0-91d7-4432-a131-3e6fd657a042 - Screen space ambient occlusion, if using SAO, is amazing. SAO test: ht…

I really wish i kept a bookmark for an article over at filfre.net, because in it a game dev, from back around the C64 era i believe, lamented how whenever there was a big step up in hardware performance, game developers had a bad habit of getting stuck trying to show how far they could push the hardware while ignoring game mechanics and similar.

Effectively whenever some new piece of hardware hit the market, the quality of games would be rolled back by a number of years as companies released what may well be glorified tech demos.

And as of late i wonder if the pace of GPU development have lead to perhaps the most prolonged period of such tech demos.

Re: Announcing Microsoft DirectX Raytracing

#20

Post by orbital-decay »

bhouston wrote: post #7

The only issue is that a lot of this is already possible in the current renderers at a reduced cost. - Soft shadows work in WebGL fairly well using PCSS: https://clara.io/player/v2/8f49e7c3-7c5e-43f0-a09c-33a55bb1b... - Translucency can be faked effectively using a few different methods. https://clara.io/view/5c7d28c0-91d7-4432-a131-3e6fd657a042 - Screen space ambient occlusion, if using SAO, is amazing. SAO test: ht…

>My experience with the game industry, even if you have a better way of doing things, if it takes more CPU/GPU cycles that a hack that achieves basically the same quality, it will not be adopted. It is that simple.

That's not always the case. Physically based materials, tonemapping and many more were widely adopted in game engines because they're easier to get proper and predictable results with. It's the same with most rendering techniques based on real physics, they are usually easier to work with, which is a very real advantage which allows devs to make more realistic environments in less time.

It's the same process that led the non-realtime world to physically based renderers, although it is slower in GPUs because of obvious hardware constraints.

Post reply on HN