- particle.c wasn't setting all components of the vector when reading cache and setting dummy velocity values.
- some functions incorrectly took a float[3] argument when the 4th value was set.
- remove a few redundant lines of code.
Reported by Jean Francois Sarazin
Lack of normal normalisation caused scaling issues. SIGGRAPH fix by jahka and jesterKing. Thanks to host dfelinto with entertainment provided by slikdigit.
* Objects are now always rotated in the directions of the hair paths
* Secondary fix: particle size wasn't updated for hair particles, so dupliobject size couldn't be change after the hair was edited
* Noise is now considered an animated texture as it changes with every frame
* Converted a few places in particles code to use the particle system's own random table instead of BLI_frand.
* Canvas and brush can be now enabled simultaneously. This way it's possible for two canvases to interact.
* Added basic anti-aliasing support for vertex surfaces.
* 3D-view color preview now works even when there's subsurf modifier after Dynamic Paint in modifier stack.
* Added a new brush option to use proximity from object center.
* Default surface frame range now use scene's start and end values.
* Improved ray checks for volume brushes.
* Added new "non-closed" option for volume brushes. This way it's possible to use planar meshes as "volume" brushes with predefined ray direction.
* New carrot branch splash image by CGEffex.
* Improved brush affection code.
* Lots of smaller improvements.
* Fixed: Weight paint didn't work with particles.
* Fixed: Point cache didn't work for non-wave surfaces anymore since last commit.
In addition the billboards can be scaled by the particle velocity with optional head and tail factors (similar to line drawing options). This allows for pseudo-motionblur effects.
Committed changes from previous weeks, biggest changes are:
* Canvas can now have multiple "surfaces" that each can have specific format, type and settings.
* Renewed UI to support this new system.
* Aside from old "image sequence" output format, Dynamic Paint can now work on vertex level as well. Currently vertex paint and displace are supported.
* Integrated vertex level painting with Point Cache.
* Added viewport preview for Point Cache surfaces.
Due to massive amount of changes, old Dynamic Paint saves are no longer supported. Also some features are temporarily missing or may not work properly.
- making local object data - Curve/Mesh/MBall lost references to linked materials.
- joining a linked mesh object into a local one lost the link.
As well as these reported bugs, checked all local functions for consistency/correctness and found other cases which would also fail.
- making local metaball didn't ensure unique ID name.
- make_local_armature() was missing check for object users - main body of code would never run.
- local particles didn't set the dupli-group or textures to extern.
checked all local functions for consistency/correctness.
the same, but big changes have happened both on the outside and on the inside.
New UI:
* The old parameters were quite true to the underlying algorithm, but were quite obscure
from a users point of view. Now there are only a few intuitive basic parameters that
define the basic fluid behavior.
** By default particle size is now used to determine the interaction radius, rest
density and spring rest lengths so that it's easy to get stable simulations by simply
emitting particles for a few frames and adjusting the particle size (easy when the
particle size is drawn) so that the fluid appears continuous (particles are touching
eachother).
** Stiffness - in reality most fluids are very incompressible, but this is a very hard
problem to solve with particle based fluid simulation so some compromises have to be
made. So the bigger the stiffness parameter is the less the fluid will compress under
stress, but the more substeps are needed for stable simulation.
** Viscosity - how much internal friction there is in the fluid. Large viscosities also
smooth out instabilities, so less viscous fluids again need more substeps to remain
stable.
** Buoancy - with high buoancy low pressure areas inside the fluid start to rise against
gravity, and high pressure areas start to come down.
* In addition to these basic parameters there are separate advanced parameters that can
either be tweaked relative to the basic parameters (or particle size) or defined
independently.
** Repulsion - the stiffness parameter tries to keep the fluid density constant, but this
can lead to small clumps of particles, so the repulsion keeps the particles better
separated.
** Stiff viscosity - the normal viscosity only applies when particles are moving closer to
eachother to allow free flowing fluids. Stiff viscosity also applies smoothing to
particles that are moving away from eachother.
** Interaction radius - by default this is 4 * particle size.
** Rest density - by default this is a density that the particles have when they're packed
densely next to eachother.
** Spring rest length - by default this is 2 * particle size.
* There are also new options for 3d view particle coloring in the display panel to show
particle velocity and acceleration. These make it easier to see what's happening in the
fluid simulations, but can of course be used with other particles as well.
* Viscoelastic springs have some new options too. The plasticity can now be set to much
higher values for instant deletion of springs as the elastic limit is exeeded. In addition
to that there is an option to only create springs for a certain number of frames when a
particle is born. These options give new possibilities for breaking viscoelastic fluids.
New in the code:
* Most of the fluids code is now thread safe, so when particle dynamics go threaded there
will be a nice speed boost to fluids as well.
* Fluids now use a bvh-tree instead of a kd-tree for the neighbor lookups. The bvh-tree
implementation makes the code quite a bit cleaner and should also give a slight speed
boost to the simulation too.
* Previously only force fields were calculated with the different integration methods, but
now the fluid calculations are also done using the selected integration method, so there
are again more choices in effecting simulation accuracy and stability. This change also
included a nice cleanup of the whole particle integration code.
As the internals are pretty stirred up old particle fluid simulations will probably not
work correctly straight away, but with some tweaking the same level of control is still
available by not using the "relative versions" of the advanced parameters (by default these
are not used when loading old files).
* Grid distribution isn't really suited for hair, so this is now disabled.
* Setting a jittered distribution with particles/face = 1 now creates particles on the center of faces.
* Quite a bit of cleanup of the whole particle distribution code.
* Tsk! Particle mirroring was working fine for the case where subsurf modifier was before particles (orcos are transformed in this case), but not the other way around (unnecessary inverse transform of orcos).
* Not really satisfied with having to check for the CD_ORIGINDEX layer, so if Brecht or somebody else knows a better way then please change this :)
- use NULL rather then 0 where possible (makes code & function calls more readable IMHO).
- set static variables and functions (exposed some unused vars/funcs).
- use func(void) rather then func() for definitions.
* Greetings from farsthary: particle rotation is now taken into account for particle effector direction.
** This gives all kinds of new possibilities as he shows in his blog http://farsthary.wordpress.com/2011/02/08/vortex-particle-simple-tut/.
**The only modification I made to his patch was to use the actual rotated particle direction as the effector direction as this defaults to the particle velocity vector, so no actual new options are needed.
* I also added an "effector amount" setting for particle effectors so that only a part of the particles can be considered as effectors. This makes it possible to create simple "farsthary vortexes" with only one particle system.
* Also some tiny reorganization of the falloff min/max values for a nicer ui.
* Effecting particle properties with textures was possible in 2.49,
but not in 2.5 anymore.
* Now particles have their own textures (available in texture panel
for objects with particle systems), which are totally separate from
the material textures.
* Currently a basic set of particle properties is available for
texture control. Some others could still be added, but the whole
system is not intended as an "change anything with a texture" as
this kind of functionality will be provided with node particles in
the future much better.
* Combined with the previously added "particle texture coordinates"
this new functionality also solves the problem of animating particle
properties through the particle lifetime nicely.
* Currently the textures only use the intensity of the texture in
"multiply" blending mode, so in order for the textures to effect
a particle parameter there has to be a non-zero value defined for
the parameter in the particle settings. Other blend modes can be
added later if they're considered useful enough.
