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Raymarching stuff looks incredible in VR but most of the available examples are web-based and the overhead of WebGL for a technique that relies on raw GPU throu
by andybak 6y ago
Raymarching stuff looks incredible in VR but most of the available examples are web-based and the overhead of WebGL for a technique that relies on raw GPU throughput often kills it.
Someone really needs to update this to work with current headsets and controllers: https://github.com/jimbo00000/RiftRay https://github.com/jimbo00000/RiftRay
(it works on the Rift last time I checked but uses the original 3DOF remove for interactions)
- GuB-42 6y agoValve actually used cdak (http://www.pouet.net/prod.php?which=55758 http://www.pouet.net/prod.php?which=55758) to demo their prototype headset. It was a specially optimized version to be able to run at full framerate on the hardware of that time. I have looked for it but it doesn't seem to be available anywhere. There is a Shadertoy version but without the optimization and last time I tried I actually had to tweak it a little to make it compile.
- CyberDildonics 6y agoWhy would raymarching and VR be different from anything else and VR? What is the overhead of webgl you are talking about? Raymarching is heavily shader dependent which shouldn't be bottlenecked by webgl at all.
- andybak 6y agoI thought there were some differences in how shaders were compiled. I'm no expert on this but my understanding was always that WebGl couldn't get the same raw performance as native apps - even at the shader level. Some of the slides here seem to support this: https://www.khronos.org/assets/uploads/developers/library/2015-gtc/NVIDIA-Shaders-WebGL-Meetup-GTC_Mar15.pdf https://www.khronos.org/assets/uploads/developers/library/20...
- CyberDildonics 6y agoWhat part of the slides support that? All it says is 'loss of performance on some mobile devices'.
- user-the-name 6y agoWhat overhead is that? Raymarching does rely on raw GPU throughput, but the common methods of doing it work by issuing extremely few API calls, and leaving the GPU alone to do the work. API overhead caused by WebGL is absolutely minuscule.
- andybak 6y agoHmmm. I need to go back and check but I'm fairly sure I've had better performance from Shadertoy shaders ported to native than I've even had running them via WebVR.