This inconsistency drove me totally crazy, it's really confusing
when it's inconsistent especially when you work on both Cycles and
Blender sides.
Shouldn;t cause merge PITA, it's whitespace changes only, Git should
be able to merge it nicely.
Issue was caused by wrong order of scene device update, which could
lead to missing object flags in shader kernel.
This patch solves a bit more than that making sure objects flags are
always properly updated, so adding/removing volume BSDF will properly
reflect on viewport where camera might become being in volume and so.
So now cases when object has both hair motion blur and deformation motion blur
vector pass is all correct.
We could get rid of the flag in the future, still need to look deeper into all
the areas trying to find a more clear solution.
This way there's much less cross-references between objects and meshes
device update functions.
The only thing remained s the object bounds calculation which is needed
by bvh update. This could also be decoupled, but it's not that crucial
yet because its's how it used to be for ages now.
This adds an AABB collision check for objects with volumes and if there's a
collision detected then the object will have SD_OBJECT_INTERSECTS_VOLUME flag.
This solves a speed regression introduced by the fix for T39823 by skipping
volume stack update in cases no volumes intersects the current SSS object.
The idea is to only count intersections with objects which has volumetric shader
and ignore all other objects.
This is probably as fast as we can go without involving some forth level magic.
Root of the issue goes back to the on-fly normals commit and the
latest fix for it wasn't actually correct. I've mixed two fixes
in there.
So the idea here goes back to storing negative scaled object flag
and flip runtime-calculated normal if this flag is set, which is
pretty much the same as the original fix for the issue from me.
The issue with motion blur wasn't caused by the rumtime normals
patch and it had issues before, because it already did runtime
normals calculation. Now made it so motion triangles takes the
negative scale flag into account.
This actually makes code more clean imo and avoids rather confusing
flipping code in mesh.cpp.
Fix T41115: Motion Blur renders Objects Black - But not in Viewport Preview
This actually extends previous fix to normals and makes it all much nicer now.
Worth doing some intense testing, quick one worked just fine but there always
could be some corner cases.
Fix T41079: Solid black render of object with negative scale and smooth shading
In both cases the issue was caused by negative scaled objects with single mesh
users for which scale gets applied when using static BVH.
Since the on-fly normals calculation land normals for such cases weren't flipped
leading them to point to a wrong direction.
Added a special object flag for this, which is a bit of a bummer because now
we've got less bits for real useful things, but this is the only way to get
proper normals without adding more complexity in the on-fly calculations.
This now supports multiple steps and subframe sampling of motion.
There is one difference for object and camera transform motion blur. It still
only supports two steps there, but the transforms are now sampled at subframe
times instead of the previous and next frame and then interpolated/extrapolated.
This will give different render results in some cases but it's more accurate.
Part of the code is from the summer of code project by Gavin Howard, but it has
been significantly rewritten and extended.
Problem is that the particle systems in the cycles database are not
stored in a well-defined order. This means the particle_id for dupli
objects can not simply be assigned using a global running index during
sync.
Now the particle index is assigned locally for each particle system.
When transferring particle data to the device as a single texture, the
particle indices are offset based on the final order of particle systems
in the database.
Reviewers: brecht
Reviewed By: brecht
CC: Andreas80
Differential Revision: https://developer.blender.org/D352
* Revert r57203 (len() renaming)
There seems to be a problem with nVidia OpenCL after this and I haven't figured out the real cause yet.
Better to selectively enable native length() later, after figuring out what's wrong.
This fixes [#35612].
* Rename some math functions:
len -> length
len_squared -> length_squared
normalize_len -> normalize_length
* This way OpenCL uses its inbuilt length() function, rather than our own. The other two functions have been renamed for consistency.
* Tested CPU, CUDA and OpenCL compile, should be no functional changes.
Now there is a single BVH traversal code with #ifdefs for various features.
At runtime it will then select the appropriate variation to use depending if
instancing, hair or motion blur is in use.
This makes scenes without hair render a bit faster, especially after the
minimum width feature was added. It's not the most beautiful code, but we can't
use c++ templates and there were already 4 copies, adding 4 more to handle the
hair case separately would be too much.
Addition of a RNA function to toggle between the hair settings and rebuild the cache. This enables the usage of the render step, child number and full display percentage with f12 rendering.
A scaling to the strand radius has also been added for the static bvh. This only matches up with dynamic for uniform scaling.
A very small fix is included for multiple uvs/vertex colours when using child particles.
should be no functional changes yet. UV, tangent and intercept are now stored
as attributes, with the intention to add more like multiple uv's, vertex
colors, generated coordinates and motion vectors later.
Things got a bit messy due to having both triangle and curve data in the same
mesh data structure, which also gives us two sets of attributes. This will get
cleaned up when we split the mesh class.
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.
Also some simple OSL optimization, passing thread data pointer directly instead
of via thread local storage, and creating ustrings for attribute lookup.
Generated and UV coordinates from the duplicator of instance instead of the
object itself.
This was used in e.g. Big Buck Bunny for texturing instanced feathers with
a UV map on the bird. Many files changed, mainly to do some refactoring to
get rid of G.rendering global in duplilist code.
