This adds a new option "Sample All Lights" to the Sampling panel in Cycles (Branched Path). When enabled, Cycles will sample all the lights in the scene for the indirect samples, instead of randomly picking one. This is already happening for direct samples, now you can optionally enable it for indirect.
Example file and renders:
Blend file: http://www.pasteall.org/blend/27411
Random: http://www.pasteall.org/pic/show.php?id=68033
All: http://www.pasteall.org/pic/show.php?id=68034
Sampling all lights is a bit slower, but there is less variance, so it should help in situations with many lights.
Patch by myself with some tweaks by Brecht.
Differential Revision: https://developer.blender.org/D391
This adds an option in the Volume Sampling panel, which helps rendering lamps
inside or near volumes with less noise. It can also increase noise though and
needs improvements to support MIS and heterogeneous volumes, but since it's
useful in some cases already (especially world volumes) it's there now.
Based on the code in the old branch by Stuart, with modifications by Thomas
and Brecht.
Differential Revision: https://developer.blender.org/D291
Indirect and Direct samples can now be clamped individually. This way we can clamp the indirect samples (fireflies), while keeping the direct highlights.
Example render: http://www.pasteall.org/pic/show.php?id=66586
WARNING: This breaks backwards compatibility. If you had Clamping enabled in an old file, you must re-enable either Direct/Indirect clamping or both again.
Reviewed by: brecht
Differential Revision: https://developer.blender.org/D303
Z, Index, normal, UV and vector passes are only affected by surfaces with alpha
transparency equal to or higher than this threshold. With value 0.0 the first
surface hit will always write to these passes, regardless of transparency. With
higher values surfaces that are mostly transparent can be skipped until an opaque
surface is encountered.
This is done by adding a Volume Scatter node. In many cases you will want to
add together a Volume Absorption and Volume Scatter node with the same color
and density to get the expected results.
This should work with branched path tracing, mixing closures, overlapping
volumes, etc. However there's still various optimizations needed for sampling.
The main missing thing from the volume branch is the equiangular sampling for
homogeneous volumes.
The heterogeneous scattering code was arranged such that we can use a single
stratified random number for distance sampling, which gives less noise than
pseudo random numbers for each step. For volumes where the color is textured
there still seems to be something off, needs to be investigated.
Volumes can now have textured colors and density. There is a Volume Sampling
panel in the Render properties with these settings:
* Step size: distance between volume shader samples when rendering the volume.
Lower values give more accurate and detailed results but also increased render
time.
* Max steps: maximum number of steps through the volume before giving up, to
protect from extremely long render times with big objects or small step sizes.
This is much more compute intensive than homogeneous volume, so when you are not
using a texture you should enable the Homogeneous Volume option in the material
or world for faster rendering.
One important missing feature is that Generated texture coordinates are not yet
working in volumes, and they are the default coordinates for nearly all texture
nodes. So until that works you need to plug in object texture coordinates or a
world space position.
This is work by "storm", Stuart Broadfoot, Thomas Dinges and myself.
This is the simplest possible volume rendering case, constant density inside
the volume and no scattering or emission. My plan is to tweak, verify and commit
more volume rendering effects one by one, doing it all at once makes it
difficult to verify correctness and track down bugs.
Documentation is here:
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Materials/Volume
Currently this hooks into path tracing in 3 ways, which should get us pretty
far until we add more advanced light sampling. These 3 hooks are repeated in
the path tracing, branched path tracing and transparent shadow code:
* Determine active volume shader at start of the path
* Change active volume shader on transmission through a surface
* Light attenuation over line segments between camera, surfaces and background
This is work by "storm", Stuart Broadfoot, Thomas Dinges and myself.
* UI: Remove deprecated condition (CURVE_RIBBONS) and hide backface property, when it's hardcoded in C (Curve/Line segments && Ribbons).
* Remove "use_tangent_normal" and "CURVE_KN_TANGENTGNORMAL" as its unused (follow up for last commit).
This actually works somewhat now, although viewport rendering is broken and any
kind of network error or connection failure will kill Blender.
* Experimental WITH_CYCLES_NETWORK cmake option
* Networked Device is shown as an option next to CPU and GPU Compute
* Various updates to work with the latest Cycles code
* Locks and thread safety for RPC calls and tiles
* Refactored pointer mapping code
* Fix error in CPU brand string retrieval code
This includes work by Doug Gale, Martijn Berger and Brecht Van Lommel.
Reviewers: brecht
Differential Revision: http://developer.blender.org/D36
* Change the default Light Path settings.
* Diffuse/Glossy bounces are now set to 4, to give a bit faster renders in default scenes. More bounces are often not needed (especially in animation).
* Transmission bounces have been increased to 12, to not run into problems with dark glass too quickly.
* Max/Min bounces are now 12/3.
* Keep the Mapping node default type as Point for now, instead of Texture. The
latter is a better default, but this is breaking API compatibility and it's
too close to release to expect addons to be fixed in time.
* Vector Transform and Mapping nodes had properties with name "type" to set the
type of vector, but this conflicts with the node type property, so renamed to
vector_type now.
scale and rotation in mapping node, there would be shearing, and the only way
to avoid that was to add 2 mapping nodes. This is because to transform the
texture, the inverse transform needs to be done on the texture coordinate
Now the mapping node has Texture/Point/Vector/Normal types to transform the
vector for a particular purpose. Point is the existing behavior, Texture is
the new default that behaves more like you might expect.
Notes:
* Made those edits by full checking of py files, so I should have spoted most needed edits, yet it remains quite probable I missed a few ones, we'll fix if/when someone notice it...
* Also made some cleanup "on the road"!
and "Branched Path Tracing", to try to make it more clear that this is not
related to progressive refinement, non-progressive was always a bad name anyway.
* Add a "Total Samples" info at the bottom of the panel.
This makes understanding the Non-Progressive integrator easier, as it displays how many samples are used for the different ray types.
* Rename Squared Samples to Square samples, to indicate that the action is not already done. The new Total Samples info should make this easier to understand now as well. Also added back for Progressive integrator, for consistency.
Screenshot:
http://www.pasteall.org/pic/show.php?id=57980
These are not animatable! Note this is the case of most (all?) render settings, maybe we should go over both Cycles and internal ones, there are still quite a bunch of them that are marked as animatable... :/
- Removed the cycles subdivision and interpolation of hairkeys.
- Removed the parent settings.
- Removed all of the advanced settings and presets.
- This simplifies the UI to a few settings for the primitive type and a shape mode.
* Non-Progressive integrator is now available on the GPU (CUDA, sm_20 and above).
Implementation details:
* kernel_path_trace() has been split up into two functions:
kernel_path_trace_non_progressive() and kernel_path_trace_progressive().
* We compile two CUDA kernel entry functions (in kernel.cu) for the two integrators, they are still inside one .cubin file but due to the kernel separation there should be no performance problem. I tested with the BMW file on my Geforce 540M and the render times were the same for 100 samples (1.57 min in my case).
This is part of my GSoC project, SVN merge of r59032 + manual merge of UI changes for this from my branch.
* Render Passes are now available for Subsurface Scattering (Direct, Indirect and Color pass).
This is part of my GSoC project, SVN merge of r58587, r58828 and r58835.
* After some feedback decided to remove this option from the Progressive integrator, it only makes sense for Non-Progressive where we have different values for the sample types.
* Add Presets for Sampling. This comes with a simple Preview and Final preset, but as this is varying a lot depending on the scene, they should just be a starting point. The user can add own presets here.
* Some UI layout changes to match the settings a bit better.
* Add a "Squared Samples" option to the UI, to use squared values for ease of use. This can make it easier from an artist point of view, to weak settings.
With this enabled, all Sample values will be squared. So 10 Samples become 100 Samples.
For the Non-Progressive integrator: 4 AA Samples * 5 Diffuse Samples would become 16 AA Samples * 25 Diffuse = 400 in total.
Patch by Matt Heimlich, with some minor edits by myself. Thanks!
* Make it more clear for the user what affects 3D View and Final render.
* Static / Dynamic BVH only affects viewport, BVH Cache only final. (see BlenderSync::get_scene_params)
