After 2.63 there was a bugfix to take object scale into account for the duplicated
objects, but this breaks compatibility on earlier files. Now there is an option to
control if the scale should be used or not.
Scale is used by default on newer files, and not used on older ones.
can type in any value, and only when sliding the number value there is a limit.
It was already possible to assign any value to a socket with node linking, so
this shouldn't cause any new issues.
Also raised the limits on the math nodes, with a patch by Agustin Benavidez.
- More angular velocity modes to support creative effects.
- Renamed "Initial Rotation" to "Initial Orientation" to better reflect the functionality
- Renamed "Spin" angular velocity mode to "Velocity".
- Organized the rotation panel a bit better.
- Also some better names and tooltips for the different rotation values.
- The main problem was that in order to be accurate all particle
rotations have to be calculated incrementally so the only working
solution is to store rotations to the point cache (previously
this was only done for dynamic rotations). This can nearly double
the point cache size so it's not ideal to have this as a default
as in many cases you don't care about particle rotations.
- Particle rotation panel now has a new "enable" checkbox that
enables rotation calculations and the storing of rotations to
point cache.
- Old files will have rotations enabled via do_versions so that in
the worst case old files will only get bigger point caches, but no
sudden loss of particle rotations.
Note about long lines: I did not touch to two pieces of code (because I don’t see any way to keep a nicely formated, compact code, with shorter lines):
* The node types definitions into rna_nodetree_types.h
* The vgroup name functions into rna_particle.c
by Gaia Clary.
Rationale: the name was confusing and not always used consistently, and this
map itself is not something that can be layered, rather the map can be used
as texture coordinates in some layered setup.
The original intent was to indicate this contained more than just UV's, but
the game engine settings have already been moved out, and apparently users
didn't really get this from the name anyway.
- remove redundant casts
- replace strcmp's with "" to just check first char.
- added WM_event_print(), debug mode only to print events since the structs values are not that meaningful.
- added warnings if locale/font dirs cant be found.
There has been quite a bit of fuss about particle dupliobject rotation in 2.59, so here are some changes to make things work a bit more consistently and predictably in 2.60.
Much of the confusion has been about what the "Initial rotation" for particles actually means. Simply put it's just a vector that that the particles (and the dupliobjects) are aligned to and around which they can be rotated with the phase controls. I've now renamed these controls under a label "Rotation axis".
In 2.59 and previous versions the dupliobject's global x-axis was aligned to the particle rotation axis for non-hair particles. This meant that the object's own rotation (in addition to the particle rotation) could effect the dupliobjects' rotations. This old behavior can still be used with the "Rotation" option in the particle render panel when object/group is set as the visualization. This option is also activated automatically for old files to maintain backwards compatibility.
Now the default dupliobject rotations ignore the object's own rotation completely and align the object's tracking axis to the particle rotation axis. The tracking axis can be found under the Object tab -> Animation Hacks panel.
In 2.58 the way of calculating the rotation for hair didn't work as intended and enabled many non-functional combinations of options. For this reason I removed most of the rotation options for hair in 2.59. Now the options have been reimplemented better and the dupliobject's tracking axis is aligned to the hair direction by default (Rotation axis = Velocity / Hair). All the other axis options work too along with the phase controls.
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.
Reviewed by Tom Musgrove and myself.
From the patch description:
ValterVB on #blendercoders submitted a long list of missing tooltips in Blender, and I went through the list and added all I knew. After that I crowdsourced the rest by putting a spreadsheet on Google docs and having people fill in the missing ones that I didn't know. So if there's some weird tooltip in there that doesn't make sense, that's why.
Thanks to Wolter, spacetug and others on BlenderArtists for contributing tooltips.
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.
* New option to distribute particles in a hexagonal grid.
* This is much more stable for fluids than normal grid distribution and looks quite nice otherwise too :)
* Also some small scale code cleanup of grid distribution code.
