Most of the changes are related to adding support for motion data throughout
the code. There's some code for actual camera/object motion blur raytracing
but it's unfinished (it badly slows down the raytracing kernel even when the
option is turned off), so that code it disabled still.
Motion vector export from Blender tries to avoid computing derived meshes
when the mesh does not have a deforming modifier, and it also won't store
motion vectors for every vertex if only the object or camera is moving.
=== BVH build time optimizations ===
* BVH building was multithreaded. Not all building is multithreaded, packing
and the initial bounding/splitting is still single threaded, but recursive
splitting is, which was the main bottleneck.
* Object splitting now uses binning rather than sorting of all elements, using
code from the Embree raytracer from Intel.
http://software.intel.com/en-us/articles/embree-photo-realistic-ray-tracing-kernels/
* Other small changes to avoid allocations, pack memory more tightly, avoid
some unnecessary operations, ...
These optimizations do not work yet when Spatial Splits are enabled, for that
more work is needed. There's also other optimizations still needed, in
particular for the case of many low poly objects, the packing step and node
memory allocation.
BVH raytracing time should remain about the same, but BVH build time should be
significantly reduced, test here show speedup of about 5x to 10x on a dual core
and 5x to 25x on an 8-core machine, depending on the scene.
=== Threads ===
Centralized task scheduler for multithreading, which is basically the
CPU device threading code wrapped into something reusable.
Basic idea is that there is a single TaskScheduler that keeps a pool of threads,
one for each core. Other places in the code can then create a TaskPool that they
can drop Tasks in to be executed by the scheduler, and wait for them to complete
or cancel them early.
=== Normal ====
Added a Normal output to the texture coordinate node. This currently
gives the object space normal, which is the same under object animation.
In the future this might become a "generated" normal so it's also stable for
deforming objects, but for now it's already useful for non-deforming objects.
=== Render Layers ===
Per render layer Samples control, leaving it to 0 will use the common scene
setting.
Environment pass will now render environment even if film is set to transparent.
Exclude Layers" added. Scene layers (all object that influence the render,
directly or indirectly) are shared between all render layers. However sometimes
it's useful to leave out some object influence for a particular render layer.
That's what this option allows you to do.
=== Filter Glossy ===
When using a value higher than 0.0, this will blur glossy reflections after
blurry bounces, to reduce noise at the cost of accuracy. 1.0 is a good
starting value to tweak.
Some light paths have a low probability of being found while contributing much
light to the pixel. As a result these light paths will be found in some pixels
and not in others, causing fireflies. An example of such a difficult path might
be a small light that is causing a small specular highlight on a sharp glossy
material, which we are seeing through a rough glossy material. With path tracing
it is difficult to find the specular highlight, but if we increase the roughness
on the material the highlight gets bigger and softer, and so easier to find.
Often this blurring will be hardly noticeable, because we are seeing it through
a blurry material anyway, but there are also cases where this will lead to a
loss of detail in lighting.
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
and 5 float image textures. For CPU render this limit will be lifted later
on with image cache support. Patch by Mike Farnsworth.
Also changed color space option in image/environment texture node, to show
options Color and Non-Color Data, instead of sRGB and Linear, this is more
descriptive, and it was not really correct to equate Non-Color Data with
Linear.
undesired dark rings, and give more accurate lighting when the light is
behind the object. As a bonus, the code is simpler & faster.
Patch by Yasuhiro Fujii, detailed explanation here:
http://mimosa-pudica.net/improved-oren-nayar.html
very well for colors that can be outside of the 0.0..1.0 range, giving +/- infinity
results.
Now we just use a simple linear contrast factor as proposed by Paolo Sourvinos, and
clamp values to be >= 0, and also make the parameters work more in the 0..1 range
instead of the 0..100 range, to be more consistent with other nodes.
texture coordinates, due to int overflow.
Also minor tweak in shader code to avoid copying uninitialized
values, should have no effect though because they were not used.
Currently supported passes:
* Combined, Z, Normal, Object Index, Material Index, Emission, Environment,
Diffuse/Glossy/Transmission x Direct/Indirect/Color
Not supported yet:
* UV, Vector, Mist
Only enabled for CPU devices at the moment, will do GPU tweaks tommorrow,
also for environment importance sampling.
Documentation:
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Passes
Contrast helps to adjust IBL (HDR images used for background lighting).
Note: In the UI we are caling it Bright instead of Brightness. This copy what Blender composite is doing.
Note2: the algorithm we are using produces pure black when contrast is 100. I'm not a fan of that, but it's a division by zero. I would like to look at other algorithms (what gimp does for example). But that would be only after 2.62.
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!
* Adding hue instead of removing it.
fmod doesn't work as % when it comes to negative numbers:
fmod( 1.3, 1) == 1.3 % 1 == 0.3
fmod(-0.3, 1) != -0.3 % 1
Node specially useful for Texture correction.
This is also a nice example of a simple node made from scratch in case someone wants to create their custom nodes.
Review by Brecht.
reviewed by Brecht, with help from Lukas.
Note: dot is reversed compared to Blender.
In Blender Normals point outside, while in Cycles they point inside.
If you use your own custom vector with the Normal Node you will see a difference.
If you feed it with object normals it should work just as good.
as with the HSV node the OSL code is relying on the (yet to be implemented) autorename.
Also the svm code could use mix (svm_lerp) instead:
32 . float3 color_inv = make_float3(1.0f, 1.0f, 1.0f) - color;
35 . . stack_store_float3(stack, out_color, svm_lerp(color_inv, color, factor));
I have a feeling that each node 'program' should have the least program as possible. I'll see with Brecht later.
But overall I don't know if that's any fast. And apart from that I think we will need this kind of function to move to a library if multiple functions linked in are not a problem.
----------------------------
reviewed and approved by Brecht
Important note:
the camera Z is reverted compared to Blender render.
Now it goes from zero (camera) to positive (in front of the camera)
.........................
note, the OSL code has a problem.
In the original node the input and output nodes have the same name (Color).
So this will be fixed here once Brecht come up with a nice autorenaming (or we do a doversion patch) for that.
Array indexing doesn't work there.
I'm yet to setup my CUDA computer, in the meantime this proved to work (tested by Daniel Salazar).
If I found other ways of doing it I get back to that.
* Fix#29257: nan-pixels with zero roughness for glass/glossy.
* Fix#29239: crash with border rendering, this is not working yet, but should
no longer crash now.
* Show object name in 3d view rendered draw type.
* Attempt to improve Sample as Light option description.
* Fix excessive fireflies in Velvet BSDF (patch by David).
* Disable some unused SSE code
* Remove RTTI disabling flags for now, this is giving some compile issues and
was only needed of OSL which we're not using yet.
* Disable precompiled cuda binaries, always do at run time
* Change preview samples default to 10
* Hide volume panels since they don't do anything yet
using them, but rather do it now that I have the chance still. Highlights:
* Wood and Marble merged into a single Wave texture
* Clouds + Distorted Noise merged into new Noise node
* Blend renamed to Gradient
* Stucci removed, was mostly useful for old bump
* Noise removed, will come back later, didn't actually work yet
* Depth setting is now Detail socket, which accepts float values
* Scale socket instead of Size socket
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/Textures
* Sun, area and point lights with size now supported
* Cast shadow option to disable shadow casting for lamps
* Emission strength of materials tweaked such that setting strength to 1.0
basically makes the material "shadeless" in that the value of the color
input will be the resulting color in the image.
decided it's better to render objects as either surface or volume.
This may break the volume rendering patch, but shaders with volume closures still
get tagged as having volume closures, so it should be fixable without too many
changes.
* 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.
* Fix missing update when editing objects with emission materials.
* Fix preview pass rendering set to 1 not showing full resolution.
* Fix CUDA runtime compiling failing due to missing cache directory.
* Use settings from first render layer for visibility and material override.
And a bunch of incomplete and still disabled code mostly related to closure
sampling.
* Compute MD5 hash to deal with nvidia opencl compiler cache not recognizing
changes in #included files, makes it possible to do kernel compile only
once and remember it for the next time blender is started.
* Kernel tweak to compile with ATI/linux. Enabling any more functionality than
simple clay render still chokes the compiler though, without a specific error
message ..
