arnold6 USD tests

I am testing new Arnold6 native USD support. Fist time to pixel is super fast, 2-3 seconds on arnold6 CPU with 1 million splines USD asset 8 sec. on Arnold6 GPU in Houdini and Gaffer.

Its a shame, that’s Autodesk HtoA plugin is is unusable. interactive rendering does not takes any updates, except shader values changes and light exposure changes. Also, Arnold6 GPU have big render artifacts with spline render mode set to “Thick”. what it look likes a cool shader, are actually render artefacts.

also arnold6 GPU renders 5 times slower then CPU version as soon i turn on SSS or transmission. ( quadro RTX5000 vs Xeon 6 core at 2.4 GHz )

testing new Arnold 6.0.3 GPU renderer update on particles


Recent HtoA 5.2.1 made it possible to actually use Arnold6 GPU in Houdini, i tool it on a test ride with particles. (5 million particles).

the setup is quite simple, pure diffuse shading only AA samples. I’ve chosen a darker frame to test the sample quality.


CPU 2 minutes on 6 core Xeon

GPU 1 minute (Nvidia Quadro RTX5000), same sample count the CPU render above but more little more noise.

GPU 1:30 minute, increased the sample to get a noise free render.

the Arnold GPU render it getting slowly faster the Arnold CPU in some cases, there is still long road ahead to for the GPU renderer speed to catch up with competition.

star simulation with OpenCL

birth of a massive star. for my little #astrophysics exploration, i’ve created a star simulation using openCL in houdini. its based on nbody #physics model, only driven by #gravity. using #nvidia #quadro rtx 5000 #NVIDIAStudio. #arnoldrender

the colours are not quite right, I am trying to integrate kelvin colour temperature.  the current colour is based on density and speed.  

In this simulation, I assumed  48% amount of negative gravity to fill the mystery of dark matter. I used 1 million nbodies for the simulation.  for the steps, I am planning to add finer particle streams to get more details.

Renderman Spline rendering

I’ve tested RenderMan with spline rendering. it’s much faster compared with baked Geometry. the spline primitives are very good in Renderman.

I’ve stopped the test with mantra after 10 minutes, it is super slow even with optimized render settings.


the Renderman images rendered for 3:20 on a 6 core Xeon
2.7ghz with pxr pathtracer. 4k resolution

geometry:

splines primitives:

rendering splines directly saves a lot disk space and meshing time. interactive rendering was super responsive.

Octane 2019.2 renderings is very fast, I’ve used the geo to render it. 2 minutes, as except its lot faster the CPU renderings. the spline rendering in octane does features custom width yet.

Octane gives physical correct shading out of the box. Renderman the shading is extreme flexible with NPR renderings, which is hard to get in Octane. the IPR responsibility was a little slow with shader tweaks.