Code is added to restrict the pixel size of strands in cycles. It works best with ribbon primitives and a preset for these is included. It uses distance dependent expansion of the strands and then stochastic strand removal to give a fading. To prevent a slowdown for triangle mesh objects in the BVH an extra visibility flag has been added. It is also only applied for camera rays.
The strand width settings are also changed, so that the particle size is not included in the width calculation. Instead there is a separate particle system parameter for width scaling.
* After PyNodes merge, many node sockets had sliders, instead of the arrow buttons (as the PROP_FACTOR subtype now actually was used). Change those back now, after artists feedback.
well as I would like, but it works, just add a subsurface scattering node and
you can use it like any other BSDF.
It is using fully raytraced sampling compatible with progressive rendering
and other more advanced rendering algorithms we might used in the future, and
it uses no extra memory so it's suitable for complex scenes.
Disadvantage is that it can be quite noisy and slow. Two limitations that will
be solved are that it does not work with bump mapping yet, and that the falloff
function used is a simple cubic function, it's not using the real BSSRDF
falloff function yet.
The node has a color input, along with a scattering radius for each RGB color
channel along with an overall scale factor for the radii.
There is also no GPU support yet, will test if I can get that working later.
Node Documentation:
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/Shaders#BSSRDF
Implementation notes:
http://wiki.blender.org/index.php/Dev:2.6/Source/Render/Cycles/Subsurface_Scattering
Also moved the sync and merge for previews into the respective tree callbacks for consistency. This way the handling of previews can be changed for each tree type individually if necessary.
* If the node tree can be updated from context (tree has get_from_context callback defined), reset the pointers first to clear the editor path if no tree can be found.
* Stupid mistake: snode->from != snode->from is always false.
* Shader nodes context update: set the 'from' pointer to the active object, even if it doesn't have a material or node tree.
PyNodes opens up the node system in Blender to scripters and adds a number of UI-level improvements.
=== Dynamic node type registration ===
Node types can now be added at runtime, using the RNA registration mechanism from python. This enables addons such as render engines to create a complete user interface with nodes.
Examples of how such nodes can be defined can be found in my personal wiki docs atm [1] and as a script template in release/scripts/templates_py/custom_nodes.py [2].
=== Node group improvements ===
Each node editor now has a tree history of edited node groups, which allows opening and editing nested node groups. The node editor also supports pinning now, so that different spaces can be used to edit different node groups simultaneously. For more ramblings and rationale see (really old) blog post on code.blender.org [3].
The interface of node groups has been overhauled. Sockets of a node group are no longer displayed in columns on either side, but instead special input/output nodes are used to mirror group sockets inside a node tree. This solves the problem of long node lines in groups and allows more adaptable node layout. Internal sockets can be exposed from a group by either connecting to the extension sockets in input/output nodes (shown as empty circle) or by adding sockets from the node property bar in the "Interface" panel. Further details such as the socket name can also be changed there.
[1] http://wiki.blender.org/index.php/User:Phonybone/Python_Nodes
[2] http://projects.blender.org/scm/viewvc.php/trunk/blender/release/scripts/templates_py/custom_nodes.py?view=markup&root=bf-blender
[3] http://code.blender.org/index.php/2012/01/improving-node-group-interface-editing/
- Cycles materials now render in Blender Internal too, skipping the nodes.
Not very useful, but at least things then show up on renders and in
previews.
- Node editor: if wrong shader nodes are in a tree, they draw with thene
color RED ALERT headers now. (Switching render engine will show it).
It was caused by image threading safe commit and it was noticeable
only on really multi-core CPU (like dual-socket Xeon stations), was
not visible on core i7 machine.
The reason of slowdown was spinlock around image buffer referencing,
which lead to lots of cores waiting for single core and using image
buffer after it was referenced was not so much longer than doing
reference itself.
The most clear solution here seemed to be introducing Image Pool
which will contain list of loaded and referenced image buffers, so
all threads could skip lock if the pool is used for reading only.
Lock only needed in cases when buffer for requested image user is
missing in the pool. This lock will happen only once per image so
overall amount of locks is much less that it was before.
To operate with pool:
- BKE_image_pool_new() creates new pool
- BKE_image_pool_free() destroys pool and dereferences all image
buffers which were loaded to it
- BKE_image_pool_acquire_ibuf() returns image buffer for given
image and user. Pool could be NULL and in this case fallback to
BKE_image_acquire_ibuf will happen.
This helps to avoid lots to if(poll) checks in image sampling
code.
- BKE_image_pool_release_ibuf releases image buffer. In fact, it
will only do something if pool is NULL, in all other case it'll
equal to DoNothing operation.
Patch [#33445] - Experimental Cycles Hair Rendering (CPU only)
This patch allows hair data to be exported to cycles and introduces a new line segment primitive to render with.
The UI appears under the particle tab and there is a new hair info node available.
It is only available under the experimental feature set and for cpu rendering.
This commit makes BKE_image_acquire_ibuf referencing result, which means once
some area requested for image buffer, it'll be guaranteed this buffer wouldn't
be freed by image signal.
To de-reference buffer BKE_image_release_ibuf should now always be used.
To make referencing working correct we can not rely on result of
image_get_ibuf_threadsafe called outside from thread lock. This is so because
we need to guarantee getting image buffer from list of loaded buffers and it's
referencing happens atomic. Without lock here it is possible that between call
of image_get_ibuf_threadsafe and referencing the buffer IMA_SIGNAL_FREE would
be called. Image signal handling too is blocking now to prevent such a
situation.
Threads are locking by spinlock, which are faster than mutexes. There were some
slowdown reports in the past about render slowdown when using OSX on Xeon CPU.
It shouldn't happen with spin locks, but more tests on different hardware would
be really welcome. So far can not see speed regressions on own computers.
This commit also removes BKE_image_get_ibuf, because it was not so intuitive
when get_ibuf and acquire_ibuf should be used.
Thanks to Ton and Brecht for discussion/review :)
A test variable needed to be absoluted (positive).
Gives expected resuts on negative raiser values.
(next; digging in opencl :)
(In old compo code too, not effective).
Shader nodes (Blender Internal), Math node Power() didn't accept negative
values for input. Added same code as for compositor case - only allow to
raise with integer values for negatives.
* Shader script node added, which stores either a link to a text datablock or
file on disk, and has functions to add and remove sockets.
* Callback RenderEngine.update_script_node(self, node) added for render engines
to compile the shader and update the node with new sockets.
Thanks to Thomas, Lukas and Dalai for the implementation.
Storing this list in the node has the advantage of requiring far fewer calls to the potentially expensive internal_connect callback. This was called on every node redraw ...
Also it will allow Cycles to properly use the internal links for muted nodes, which ensures consistent behavior. The previous method was not applicable in Cycles because transient list return values are not supported well in the RNA and particularly the C++ API implementation.
not do correct partial updates, now it remembers if the opengl texture is a
non-color data texture or not and takes that into account for the update.
Also includes some renaming ncd => is_data for consistency with color space
terminology used elsewhere.
It is not a well-supported feature of the primary node systems (shader, compositor, texture) in Blender. If anybody wants to create a node system that has actual use for loops, they can do so much more elegantly with Python nodes, but it does not have to be a core node type in Blender. Removing this should ease node code maintenance a bit.
when tree is being executed. This could lead to nor initialized color space
for the image.
Solved by insuring image buffer is loaded before checking for whether color
conversion is needed.
