Commit Graph

5 Commits

Author SHA1 Message Date
Brecht Van Lommel
5873301257 Sample as Lamp option for world shaders, to enable multiple importance sampling.
By default lighting from the world is computed solely with indirect light
sampling. However for more complex environment maps this can be too noisy, as
sampling the BSDF may not easily find the highlights in the environment map
image. By enabling this option, the world background will be sampled as a lamp,
with lighter parts automatically given more samples.

Map Resolution specifies the size of the importance map (res x res). Before
rendering starts, an importance map is generated by "baking" a grayscale image
from the world shader. This will then be used to determine which parts of the
background are light and so should receive more samples than darker parts.
Higher resolutions will result in more accurate sampling but take more setup
time and memory.

Patch by Mike Farnsworth, thanks!
2012-01-20 17:49:17 +00:00
Brecht Van Lommel
66b1dfae89 Cycles: tweaks to properties and nodes
* Passes renamed to samples
* Camera lens radius renamed to aperature size/blades/rotation
* Glass and fresnel nodes input is now index of refraction
* Glossy and velvet fresnel socket removed
* Mix/add closure node renamed to mix/add shader node
* Blend weight node added for shader mixing weights

There is some version patching code for reading existing files, but it's not
perfect, so shaders may work a bit different.
2011-09-16 13:14:02 +00:00
Brecht Van Lommel
63d4bafff5 Cycles: some steps to getting OpenCL backend to compile. 2011-05-20 12:26:01 +00:00
Brecht Van Lommel
922bb24865 Cycles: color space control for image/environment texture nodes. Ideally would
be automated but need to think about how to do this, not so simply in a node
system. But guideline for now is, for color textures set to sRGB, for things like
bump or roughness map, set to Linear.
2011-05-13 14:32:08 +00:00
Ton Roosendaal
da376e0237 Cycles render engine, initial commit. This is the engine itself, blender modifications and build instructions will follow later.
Cycles uses code from some great open source projects, many thanks them:

* BVH building and traversal code from NVidia's "Understanding the Efficiency of Ray Traversal on GPUs":
http://code.google.com/p/understanding-the-efficiency-of-ray-traversal-on-gpus/
* Open Shading Language for a large part of the shading system:
http://code.google.com/p/openshadinglanguage/
* Blender for procedural textures and a few other nodes.
* Approximate Catmull Clark subdivision from NVidia Mesh tools:
http://code.google.com/p/nvidia-mesh-tools/
* Sobol direction vectors from:
http://web.maths.unsw.edu.au/~fkuo/sobol/
* Film response functions from:
http://www.cs.columbia.edu/CAVE/software/softlib/dorf.php
2011-04-27 11:58:34 +00:00