LuxCoreRender Forums

FarbigeWelt wrote: ↑Mon Dec 10, 2018 6:41 pm Higher resolutions lead to better results with denoiser. 1xHD images was not nice.

I am pretty sure now that I know what lead to the disturbing low res images.
Instead of the bar light in the current scene I used two hollow spheres to get indirect light.
I may retry with the indirect light to be sure enough.

B.Y.O.B. wrote: ↑Mon Dec 10, 2018 7:28 pm

FarbigeWelt wrote: ↑Mon Dec 10, 2018 6:25 pm Path rendrer seems not work with well with heterogenous, scattering medium.

I did not encounter any problems yet, all my smoke renders were done with Path OpenCL.
Maybe your problems were caused by something else, e.g. the spotlights being not-intersectable light sources?

BiDir lead so far to the only expected result. Most close path with three suns. However using point lights instead of spot lights improved the result remarkably. Now I have almost what I intended to get. Many thanks for the tip, and sure the dolphins would say "So long! And thanks for the fish!" (Douglas Adams)

50 Samples in both cases, spot the different denoiser results!

At least I don’t have to care about statics.
The pool on to top 5*5*1.2 m^3 equals 30 tons or 1.2 ton per sqm.

Beer Foam 2.0

Background
Due to the fact my latest version of the dark beer scene „Hinech“ does not render foam through glass visibly anymore neither BiDir nor UniDir path, I started from scratch to get the picture I like to have.

Goals
Natural looking foam on (and in) liquids.
Faster particle simulation, shorter render times, reliability of scene setup.

Render times about 2 minutes for 1 Mpixel images on my 2 GPU.
Wireframe: Blender internal.

Funny Intermediates

After fooling myself with setting parameters of both Blender particle system and the plugin ‚Molecular script’ for hours, I found first steps for creating foam in a container.

The plugin simulates self collision between particles something what Blender unfortunately does not simulate.
As observed, there are many ways to crash Blender reproducibly with both simulators. Therefore auto-saving the scene every two minutes is a welcome feature if one does not like to get a very bad mood.

To use the plugin ‚Molecular script’ Blender Physics: must not be chosen ‚No’, otherwise particles keep their initial place, they keep initial place too if subframe is not set to zero.

Because particles jump if value .Timestep, in ‚Paricles’ submenu ,Physics’ is set to default 1/30 ([s] per frame).
Actually lower values make much sense, the particles’ animations get smoother and more accurate.
Lower values here mean e.g. 1/256 (observation: lower values than 1/1024 can crash Blender).

The plugin‘s simulation is visible, e.g. wireframe or solid, it starts after a click on the button ,Simulation‘.
This kind of simulation is slow because its speed depends on drawing speed, which is often at rates much below 25 [frames/s], especially if particles number larger than 250.

Default plugin value ‚mol_substep‘ is 4. This value can be decreased, although higher values increase simulation‘s accuracy, they also increase time. However, if value of ‚Timesteps‘ is e.g. a tenth of its default value; ‚mol_step‘ set to zero may fit as although results differ much using higher values due to resolving and then avoiding overlapping particles the better the higher the value of , mol_step is set.

Anyway, the simulation is much faster if started with a click on the button ‘Bake all Dynamics‘ in the ‚Particles’ submenu ‚Cache‘.
But way leads to different results because simulation is done with Blender ,Particles‘ and not with the plugin.

Currently, I am interested in understanding interaction of ,Particles‘ parameter with the plugin if only its self collision feature is enabled. After that I am going to enable plugin‘s particle linking feature. Sure I have already some experiences with that but it is very difficult to understand what its parameter do if there is an interaction with ,Particles, parameter.

The picture above is from the same scene but with different path depths of total 12, the other three are 10 and the render time was 11h32 instead of 6h20m.

Brightness and gamma of following picture are heavily amplified to make the difference visible. With default brightness and gamma the picture is completely dark. The onion like rings are interesting, aren't they? Indeed path depth of former render was not needed. But then, decreasing path depth did not alter speed much as one can see in the table below.

FarbigeWelt wrote: ↑Mon Apr 08, 2019 8:47 pm The onion like rings are interesting, aren't they?

My guess is: floating point precision limits

Behaviour with total path depth of only 6.