Fix T45381: Crash Blender 2.75 in Win7 x64 AMD card
The issue is basically caused by graphics card driver which crashes when
querying OpenCL platforms. This isn't something we can really solve from
the CLEW side, because opencl.dll does exist in old driver and even has
all the needed symbols, but first ever call to clGetPlatformIDs crashes.
While rest of the blender works fine with those older ATI/AMD cards it's
really needed to solve crashes of OpenCL device enumeration.
Solution here is to force disable OpenCL platforms if we've detected that
display card is using old ATI/AMD driver. It's not really proper solution
so it's done in the python side where it's easy to do tweaks. Reasoning
behind this change is:
- If one uses really old driver it's likely because it's the latest one
he/she can ever to install (because of discontinued support from AMD).
- If old card is used it's likely to not have dedicated GPUs for rendering.
- Even if there's a dedicated GPU device enumeration is likely to crash
because of attempt to query OpenCL from the old card.
There are still some tweaks needed likely, but this commit should make
some of the configurations to work.
extensions, once to get final context extensions.
Not so nice because we get a warning on startup from GLEW, but at least
it GL extensions should work now.
This commit implements point density texture for Cycles shading nodes.
It's done via creating voxel texture at shader compilation time, Not
totally memory efficient, but avoids adding sampling code to kernel
(which keeps render time as low as possible), In the future this will
be compensated by using OpenVDB for more efficient storage of sparse
volume data.
Sampling of the voxel texture is happening at blender side and the
same code is used as for Blender Internal's renderer.
This texture is controlled by only object, particle system and radius.
Linear falloff is used and there's no turbulence. This is because
falloff is expected to happen using Curve Mapping node. Turbulence
will be done as a distortion on the input coordinate. It's already
possible to fake it using nose textures and in the future we can add
more proper turbulence distortion node, which then could also be used
for 2D texture mapping.
Particle color support is done by Lukas, thanks!
The idea of this node is to sampling of 3D voxels at a given coordinate
supporting different mapping strategies (world space mapping, object
local space etc).
Currently not in use, it's a preparation step for supporting point density
textures.
The idea is to give artists a simplier way to control memory usage in such
scenes as grass fields by doing automatic object culling based on whether
object is visible in the frame or not.
This is controlled on per-object level. In order to use this option few steps
are required:
- Enable Simplify in scene settings
- Enable Camera Cull option in the Simplify panel
- Set camera cull margin (measured in relative value to the render resolution)
This setting is used to avoid possible flickering caused by changes in shadow
which are cast by objects outside of the frame.
- Enable Camera Cull for objects which are desired to be culled
(object culling option could be found in Option panel in object buttons).
There is still room for improvements, but this worked quite well during
Gooseberry open movie project, so think it's useful feature even in it's current
non-ideal state.
This means render devices now might skip building baking kernels in cases when
only actual render-related functionality is used.
For now it's only implemented for OpenCL split kernel device and mainly needed
to work around some compiler-specific bugs which crashes on building the kernel.
Using OpenCL for baking might still crash the driver, but at least there is now
higher probability of that GPU will be usable to render the scene.
Real fix should actually be done in the driver side.
The idea is to make all kernels as small as possible to work around possible
issues with buggy drivers which might fail building feature-complete kernels.
It's indeed just a workaround to make at last simple test scenes to render
on OpenCL. Real fix should happen from the driver side.
It is rather annoying attitude nowadays to use const qualifier all over the
place, including using it for multi-dimensional arrays. This isn't really
supported in GCC prior to version 5.0 because it considers such an arrays
to be a "pointer to a const pointer" which gives implicit casting errors.
It's not possible to disable this particular type of warnings treated as
errors in any GCC version prior to 5.0 as well, meaning currently usage of
-Werror globally in Blender code is not possible at all.
This commit makes it possible to use -Werror in areas which are complaint
with older GCC versions. New advanced CMake options are:
- WITH_COMPOSITOR_WERROR
- WITH_LIBMV_WERROR
- WITH_CYCLES_WERROR
Turning on importance sampling on area lights increases noise on diffuse
surfaces. This was caused by PDF calculated for an intersected point on
light instead of original light position.
Patch by Stefan with some own modifications.
Requires having latest El Capitan beta 3 OSX due to ome crucial fixes made in the
compiler. Supports same features as NVidia OpenCL apart from CMJ (there's no
experimental feature set support in megakernel yet).
Uses megakernel internally, which works much better than the split kernel. Split
kernel is not supported on OSX still, needs to be investigated still.
Some more details can be found there:
http://wiki.blender.org/index.php/Dev:2.6/Source/Render/Cycles/OpenCL#AMD_on_OSX
From artists perspective it makes sense to always apply displacement in a local
space.
TODO: Double-check that BVH is being packed properly. From quick tests seems it's
all fine, but might be missing some obvious failure still.
When using MIS, the world is treated as regular light and in this case
we can now also limit the maximum amount of bounces, the background light
will contribute to the scene.
This can improve performance in some cases, where it's e.g. sufficient to
only have a contribution on first 1-2 bounces.
Examples can be found in the differential.
Differential revision: https://developer.blender.org/D1399
option.
This makes sense, since contexts get created at runtime, there is little
reason to require recompilation for this.
Only works on linux currently, will be doing more OSs later
This is not really supported by OpenCL but might happen in certain
configurations. There might be some remained cases when this happens
but so far can not find any,
The issue was caused by some changes made to msgfmt which were needed to make
modified (cleaned-up, stripped-comments messages) working.
Unfortunately that fix was merged into the release branch, so this fix is to
be ported there as well and verified against rc1 translations.
