This was in fact really nasty bug, caused by multitex_nodes
function using global variable R (which is a copy of current
renderer). this variable is not initialized to anything
meaningful for until first rendering (preview or final)
happened.
Since multitex_nodes might be used outside of render pipeline,
made it so whether CM is on or off as an argument to functions
multitex_ext_safe and multitex_ext. Now multitex_nodes() is
only shall be used for stuff happening from render pipeline!
Also needed to make some changes to other places, so all the
usages of texture sampling knows for the fact whether CM is
on or off.
And one more change is related on behavior of dispalcement,
wave, warp, weightvg modifiers and smoke. They'll be always
using CM off since texture is used for influence, not for
color.
It's rather bigger patch, but it's mostly straightforward
changes, which we really need to be done.
Reviewed by Brecht, thanks!
many modifiers were calculating normals, when those normals were ignored by the next modifier.
now flag normals as dirty and recalculate for modifiers that set use `dependsOnNormals()` callback.
Quick test on mesh with 12 modifiers (mostly build type), calculated normals 6 times, now it only runs once - so this will give some speedup too.
This caused high resolution smoke to always regenerate new tile when domain was reinitialized, slowing down especially adaptive domain simulations. Now noise tile is saved in Blender temp directory instead.
Previously it was nearly impossible to have fast moving objects emitting smoke or they would just leave behind a row of smoke poofs instead of continious stream of smoke. Now it's possible to set number of subframes for each smoke flow.
Another new thing is ability to set size of smoke flow particles instead of using closest smoke cell. This also works with my earlier "full sample" commit, so no more blocky particles either. :)
For more info check my blog post: http://www.miikahweb.com/en/blog/2013/05/17/blender-smoke-subframes
This commit also includes couple of fixes I spotted while testing:
* Fix: dissolve was applied at different time for low res and high res simulations.
* Fix: full sample setting didn't get copied with domain.
This is hopefully the ultimate solution against smoke blockiness near emitter.
Previously high resolution flow/emitter voxels were generated based on the low resolution ones. So if you had 32 resolution and 4 division high resolution, it still used smoke flow generated from those 32 resolution voxels. Now I introduced a new sampling method called "Full Sample" that generates full resolution flow for for high resolution domain as well.
Read more about it in my blog post: https://www.miikahweb.com/en/blog/2013/05/10/getting-rid-of-smoke-blockiness
Also changed "quick smoke" operator default voxel data interpolation mode to "Cubic B-Spline" to smoothen out it even more.
Issue was introduced by svn rev56273 and was caused by
both smokeModifier_do and smokeModifier_reset (which is
called from smokeModifier_do) do mutex lock/unlock.
This lead to quite undefined behavior caused by the same
thread released mutex twice.
Solved by not locking mutex from inside routines calling
from smokeModifier_process -- mutex is locked in parent
function anyway.
Added a mutex lock for smoke data access. The render was already working with a
copy of the volume data, so it's just a short lock to copy things and should not
block the UI much.
generator with a local one. It's not thread safe and will not give repeatable
results, so in most cases it should not be used.
Also fixes#34992 where the noise texture of a displacement modifier was not
properly random in opengl animation render, because the seed got reset to a
fixed value by an unrelated function while for final render it changed each
frame.
In some cases high resolution domain could have higher density than the low resolution counterpart, causing adaptive domain to clip off areas where density is still above domain threshold. Now also high resolution data is used to determine domain bounds.
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.
Documentation & Test blend files:
------------------
http://wiki.blender.org/index.php/User:MiikaH/GSoC-2012-Smoke-Simulator-Improvements
Credits:
------------------
Miika Hamalainen (MiikaH): Student / Main programmer
Daniel Genrich (Genscher): Mentor / Programmer of merged patches from Smoke2 branch
Google: For Google Summer of Code 2012
a) Another boundary fix. Resulted in smoke getting "sucked" back into the domain
b) Disabling substeps (internal thing). Fixes arbitrary explosions/instabilities.
Part of my Blender Smoke Development.
Detail: Smoke solver and Blender side of smoke now share the same cell length.
First reported by the Sintel artists long ago, again reported by MiikaH.
Part of my Smoke Development Project Phase III.
