Commit Graph

19 Commits

Author SHA1 Message Date
Thomas Dinges
88b30ccb8c Cycles:
* Style cleanup for M_PI constants.
* Move Wireframe node into __EXTRA_NODES__ define
2013-06-14 14:29:00 +00:00
Brecht Van Lommel
b20a7e01d0 Cycles: experimental correlated multi-jittered sampling pattern that can be used
instead of sobol. So far one doesn't seem to be consistently better or worse than
the other for the same number of samples but more testing is needed.

The random number generator itself is slower than sobol for most number of samples,
except 16, 64, 256, .. because they can be computed faster. This can probably be
optimized, but we can do that when/if this actually turns out to be useful.

Paper this implementation is based on:
http://graphics.pixar.com/library/MultiJitteredSampling/

Also includes some refactoring of RNG code, fixing a Sobol correlation issue with
the first BSDF and < 16 samples, skipping some unneeded RNG calls and using a
simpler unit square to unit disk function.
2013-06-07 16:06:22 +00:00
Thomas Dinges
6b7d2ed8b6 Code cleanup / Cycles:
* Use M_2PI_F in more places and do multiplication instead of division in gradient texture.
2013-05-21 13:22:11 +00:00
Thomas Dinges
7636aeffe1 Cycles / Math:
* Add M_2PI_F and M_4PI_F constants and use them inside the codebase.
2013-05-12 14:13:29 +00:00
Brecht Van Lommel
54729df020 Cycles OSL: diffuse_toon and specular_toon closures. These are toon shaders with
a size parameter between 0.0 and 1.0 that gives a angle of reflection between
0° and 90°, and a smooth parameter that gives and angle over which a smooth
transition from full to no reflection happens.

These work with global illumination and do importance sampling of the area within
the angle. Note that unlike most other BSDF's these are not energy conserving in
general, in particular if their weight is 1.0 and size > 2/3 (or 60°) they will
add more energy in each bounce.

Diffuse: http://www.pasteall.org/pic/show.php?id=42119
Specular: http://www.pasteall.org/pic/show.php?id=42120
2012-12-19 21:17:16 +00:00
Brecht Van Lommel
f0a9b66469 Cycles: Anisotropic BSDF enabled, with tangents now computed from the active UV map.
It's using the Ward BSDF currently, which has some energy loss so might be a bit
dark. More/better BSDF options can be implemented later.

Patch by Mike Farnsworth, some modifications by me. Currently it's not possible yet
to set a custom tangent, that will follow as part of per-bsdf normals patch.
2012-10-10 13:02:20 +00:00
Campbell Barton
fbe13ab84a style cleanup 2012-09-20 12:29:28 +00:00
Campbell Barton
a199ae5368 style cleanup: whitespace, also add '?' to save over popup since it wasnt totally clear it was a question (user pointed this out, they thought it was just notification and lost their work). 2012-07-31 23:06:12 +00:00
Campbell Barton
0fbb6bff27 style cleanup: block comments 2012-06-09 17:22:52 +00:00
Brecht Van Lommel
022d12a721 Fix most of #31307: cycles panorama camera not working correct with speed
vectors and window texture coordinates. Only for Fisheye Equisolid it's
still not working correct yet. Patch from Dalai with modifications.
2012-05-07 10:53:09 +00:00
Brecht Van Lommel
c0331cfc09 Cycles: minor refactoring of fisheye code to fit code style. 2012-05-05 19:44:35 +00:00
Dalai Felinto
d710638c47 small fix for equisolid fisheye (cycles)
the FOV formular is: R = 2 * lens * sin (theta / 2)
in this case theta is fov/2 already, thus the fix
2012-05-04 16:29:41 +00:00
Dalai Felinto
d7fbe03a8a Fisheye Camera for Cycles
For sample images see:
http://www.dalaifelinto.com/?p=399 (equisolid)
http://www.dalaifelinto.com/?p=389 (equidistant)

The 'use_panorama' option is now part of a new Camera type: 'Panorama'.
Created two other panorama cameras:

- Equisolid: most of lens in the market simulate this lens - e.g. Nikon, Canon, ...)
             this works as a real lens up to an extent. The final result takes the
             sensor dimensions into account also.
             .:. to simulate a Nikon DX2S with a 10.5mm lens do:
                 sensor: 23.7 x 15.7
                 fisheye lens: 10.5
                 fisheye fov: 180
                 render dimensions: 4288 x 2848

- Equidistant: this is not a real lens model. Although the old equidistant lens simulate
               this lens. The result is always as a circular fisheye that takes the whole sensor
               (in other words, it doesn't take the sensor into consideration).
               This is perfect for fulldomes ;)

               For the UI we have 10 to 360 as soft values and 10 to 3600 as hard values (because we can).


Reference material:
http://www.hdrlabs.com/tutorials/downloads_files/HDRI%20for%20CGI.pdf
http://www.bobatkins.com/photography/technical/field_of_view.html

Note, this is not a real simulation of the light path through the lens.
The ideal solution would be this:
https://graphics.stanford.edu/wikis/cs348b-11/Assignment3
http://www.graphics.stanford.edu/papers/camera/


Thanks Brecht for the fix, suggestions and code review.
Kudos for the dome community for keeping me stimulated on the topic since 2009 ;)

Patch partly implemented during lab time at VisGraf, IMPA - Rio de Janeiro.
2012-05-04 16:20:51 +00:00
Brecht Van Lommel
9b8dae71a5 Cycles: support for environment texture "Mirror Ball" projection mode, next to
existing "Equirectangular". This projection is useful to create light probes
from a chrome ball placed in a real scene. It expects as input a photograph of
the chrome ball, cropped so the ball just fits inside the image boundaries.

Example setup with panorama camera and mixing two (poor quality) photographs
from different viewpoints to avoid stretching and hide the photographer:
http://www.pasteall.org/pic/28036
2012-03-08 19:52:58 +00:00
Brecht Van Lommel
4a90339519 Cycles: support for camera rendering an environment map with equirectangular
environment map, by enabling the Panorama option in the camera.

http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Camera#Panorama

The focal length or sensor settings are not used, the UI can be tweaked still to
communicate this, also panorama should probably become a proper camera type like
perspective or ortho.
2012-02-28 16:44:54 +00:00
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
cdee3435c6 Cycles: internal changes that should have no effect on user level yet, added
shader flags for various purposes, and some code for light types other than
points.
2011-09-27 20:37:24 +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
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