sb->lcom : Center Of Mass .. might be used to create loc IPO
sb_>lrot : is a matrix[3] esitmates the roatation in world coordinates .. might be used to create rot IPO
sb_>lscale : is a matrix[3] esitmates the scaling in world coordinates .. might be used to create scale IPO
(no python for that yet .. but may be matt has mercy on me )
can be cropped direclty in soft body module by function
static void SB_estimate_transform(Object *ob,float lloc[3],float lrot[3][3],float lscale[3][3])
The targets lloc,lrot,lscale should work to be NULL, just in case you don't need it.
However i'd prefer if they were accessed via properties
which should be calculated automagically if
sb->solverflags & SBSO_ESTIMATEIPO
is set, like they do in draw_sb_motion(..) in drawobject.c
added static void draw_sb_motion(Scene *scene, Object *ob) to drawobject.c
for debuggering (had a hard time with destructive matrix operations )
if it causes any trouble with your build on any OS make sure to comment that away.
softbody.c and DNA should compile fine in any case.
- HEADER (beginning of each file)
* general header:
+ 8 char: "BPHYSICS"
+ 1 int: simulation type (same as PTCacheID->type)
* custom header (same for sb, particles and cloth, but can be different for new dynamics)
+ 1 int: totpoint (number of points)
+ 1 int: data_types (bit flags for what the stored data is)
- DATA (directly after header)
*totpoint times the data as specified in data_types flags
- simulation type
soft body = 0, particles = 1, cloth = 2
- data types (more can be added easily when needed)
data flag contains
----------------------------------------
index (1<<0) 1 int (index of current point)
location (1<<1) 3 float
velocity (1<<2) 3 float
rotation (1<<3) 4 float (quaternion)
avelocity (1<<4) 3 float (used for particles)
xconst (1<<4) 3 float (used for cloth)
size (1<<5) 1 float
times (1<<6) 3 float (birth, die & lifetime of particle)
boids (1<<7) 1 BoidData
Notes:
- Every frame is not nescessary since data is interpolated for the inbetween frames.
- For now every point is needed for every cached frame, the "index" data type is reserved for future usage.
- For loading external particle caches only "location" data is necessary, other needed values are determined from the given data.
- Non-dynamic data should be written into an info file if external usage is desired.
* Info file is named as normal cache files, but with frame number 0;
* "Non-dynamic" means data such as particle times.
* Written automatically when baking to disk so basically a library of particle simulations should be possible.
- Old disk cache format is supported for reading, so pre 2.5 files shouldn't break. However old style memory cache (added during 2.5 development) is not supported. To keep memory cached simulations convert the cache to disk cache before svn update and save the blend.
- External sb and cloth caches should be perfectly possible, but due to lack of testing these are not yet enabled in ui.
Other changes:
- Multiple point caches per dynamics system.
* In the future these will hopefully be nla editable etc, but for now things are simple and the current (selected) point cache is used.
* Changing the amount of cached points (for example particle count) is allowed, but might not give correct results if multiple caches are present.
- Generalization of point cache baking etc operator & rna code.
- Comb brushing particle hair didn't work smoothly.
Note: Rna access to softbody point cache is through softbody modifier although the point cache is in softbody settings. This is to make it similar to cloth.
Bugfix: Softbody rna was trying to get "ob->soft->softflag" instead of the correct "ob->softflag".
missing commits from peter 20942, 21165, 21170, 21174, 21597
these files still need manual merging
source/blender/makesdna/DNA_sequence_types.h
source/blender/src/sequence.c
source/blender/src/seqeffects.c
source/blender/src/editseq.c
source/blender/include/BSE_sequence.h
Think global, act local!
The old favorite G.scene gone! Man... that took almost 2 days.
Also removed G.curscreen and G.edbo.
Not everything could get solved; here's some notes.
- modifiers now store current scene in ModifierData. This is not
meant for permanent, but it can probably stick there until we
cleaned the anim system and depsgraph to cope better with
timing issues.
- Game engine G.scene should become an argument for staring it.
Didn't solve this yet.
- Texture nodes should get scene cfra, but the current implementation
is too tightly wrapped to do it easily.
=======================
Caching and Baking:
- The point cache is now cleared on DAG_object_flush_update(), and not cleared for time dependency graph updates.
- There is now a Bake button instead of Protect. Also cache start and end frames were added to softbody and particles.
- The cloth autoprotect feature was removed.
- The Ctrl+B menu now also bakes cloth and particles next to softbody and fluids. Additionally there are now frree bake and free cache menu entries.
- The point cache api has been changed. There is now a PTCacheID struct for each point cache type that can be filled and then used to call the point cache functions.
- PointCache struct was added to DNA and is automatically allocated for each physics type.
- Soft body now supports Bake Editing just like cloth.
- Tried to make the systems deal consistently with time ipo's and offsets. Still not sure it all works correct, but too complicated to solve completely now.
Library Linking:
- Added some more warnings to prevent editing settings on library linked objects.
- Linked objects now read from the cache located next to the original library file, and never write to it. This restores old behavior for softbodies. For local simulation the mesh and not the object should be linked.
- Dupligroups and proxies can't create local point caches at the moment, how to implement that I'm not sure. We probably need a proxy point cache for that to work (ugh).
Physics UI:
- Renamed deflection panel to collision for consistency and reorganized the buttons. Also removed some softbody collision buttons from the softbody panel that were duplicated in this panel for cloth.
- Tweaked field panel buttons to not jump around when changing options.
- Tabbing e.g. Soft Body Collision into the Soft Body panel, it now only shows Collision to make the panel names readable.
- I tried to make enabled/disabling physics more consistent, since all three system did things different. Now the two modifier buttons to enable the modifier for the viewport and rendering are also duplicated in the physics panels. Toggling the Soft Body and Cloth buttons now both remove their modifiers.
- Fixed modifier error drawing glitch.
Particles:
- Particles are now recalculated more often than before. Previously it did partial updates based on the changes, but that doesn't work well with DAG_object_flush_update() ..
- Fixed memory leak loading keyed particle system. Now keys are not written to file anymore but always created after loading.
- Make particle threads work with autothreads.
Continue Physics:
- The timeline play now has a Continue Physics option in the playback menu, which keeps the simulations going without writing them to the cache.
- This doesn't always work that well, some changes are not immediately updated, but this can be improved later. Still it's fun to get a feel for the physics.
Todo:
- Point cache can get out of sync with and undo and changing a file without saving it.
- Change the point cache file format to store a version (so old point cache files can be either converted or at least ignored), and to do correct endian conversion.
- Menu item and/or buttons for Ctrl+B.
- A system("rm ..") was changed to remove() since the former is very slow for clearing point caches. These system() calls were already giving trouble in a bug in the tracker, but really most use of this system("") should be changed and tested.
- The Soft Body Collision and Clot Collision panel titles don't mention there's point cache settings there too, doing that makes them unreadable with the default panel setup.. but may need to make the names longer anyway.
a glance to view is the "STU PID semi implicit euler"
most of the work to implement a semi implicit euler was done ..
now i am dealing with the tradeoffs between 'calculation time' which is quite expensive .. inverting a 0(n*n) sparse matrix /* once agian thanks to brecht for his work on making sparse matrices LU decomposition and evaluating inverses that easy*/ putting it into and cropping works pretty nice .. argh off topic again
...
while i spent a little time on reading recent papers i found :
1. control on springs needs to be split in pushing and pulling /* fabric pushes easy but pulls hard */
2. diagonals on 4-gons (in the current SB model) can be seen as shear .. thus need a contol to modify .. this commit wil add it
3. 2 nd order springs /*aka rigidity */ can focus on bending .. thus renaming 'em
i have no idea how i would provide backward compatiblity, but the spots i marked in code :)
=========
Merge of the famous particle patch by Janne Karhu, a full rewrite
of the Blender particle system. This includes:
- Emitter, Hair and Reactor particle types.
- Newtonian, Keyed and Boids physics.
- Various particle visualisation and rendering types.
- Vertex group and texture control for various properties.
- Interpolated child particles from parents.
- Hair editing with combing, growing, cutting, .. .
- Explode modifier.
- Harmonic, Magnetic fields, and multiple falloff types.
.. and lots of other things, some more info is here:
http://wiki.blender.org/index.php/BlenderDev/Particles_Rewritehttp://wiki.blender.org/index.php/BlenderDev/Particles_Rewrite_Doc
The new particle system cannot be backwards compatible. Old particle
systems are being converted to the new system, but will require
tweaking to get them looking the same as before.
Point Cache
===========
The new system to replace manual baking, based on automatic caching
on disk. This is currently used by softbodies and the particle system.
See the Cache API section on:
http://wiki.blender.org/index.php/BlenderDev/PhysicsSprint
Documentation
=============
These new features still need good docs for the release logs, help
for this is appreciated.
- new feature, twiddled with lattice resizing to try to maintain
existing vertex changes... much nicer than just resetting the
lattice if you decide you need more detail in the lattice.
- modifiers work with lattices now. yes, that does mean you
can make a chain of lattices effecting each other 8 miles
long.
- some cleanup of softbody code, was rather splintered and call
path was twisted and confusing. reworked main object step
routine to do things in a more obvious and consistent manner
and without duplicate code
- added ob->softflag OB_SB_RESET instead of sbObjectReset
call
- modifier changes reset softbody now
- moved curve_getVertexCos/curve_applyVertexCos into curve.c
- update curve modifier eval to work with virtual modifiers
- update modifier apply to work with curves/surfs
- update make parent to also recalc object data
NOTE: Although you can turn SB on for curve/font objects at the
moment it doesn't really work because they call deform in
multiple steps and this confuses SB. Not sure how to deal with
atm.
- added verteCos argument to sbObjectReset, lack of this was
causing softbody objects to not be initialized with deform
- made convert-to-mesh option call DAG_scene_sort, prevents
crashes due to obsolete object pointer
- changed mesh_modifier, sbObjectStep, object_deform to take vertexCo
argument instead of operating on mesh
- fixed bug where a derived mesh would not be returned in editmode
- removed object_wave, replaced by init_wave_deform and calc_wave_deform
- moved cached DerivedMesh to Object, not Mesh... fixes heisenbugs
with linked objects
(which still can't really handle moving targets)
leaving 2 bug fixes
1. multiple objects need a reset on cache variable
2. quads always need to be handled as 2 triangles
(since they don't need to share a plane)
added a collision detecting function in effect.c for SB
( no need to be there, but i did not find a better place )
but should handle 'moving targets' up to 0.2 blender units/frame
well .. important info in this case:
collision
uses 'face normal' to decide if *intrusion* happend
uses 'damping' of collision target to slow down movement
when *intrusion* happend
+some more removing unneeded code in softbody.c
User level notes are in Wiki here;
http://wiki.blender.org/bin/view.pl/Blenderdev/Softbodies
And will be added in blender3d.org CMS later.
Tech level notes are still pending, but here's the most relevant ones;
- made ob->soft struct SoftBody to hold all settings, and read/save in
files
- added (temporal!) conversion for the old settings. So: read old files
with softbody experiments now, and save over!
- cleaned API calls for softbody, which are only 5 of them now:
sbNew()
sbFree()
sbObjectStep() (animation steps)
sbObjectToSoftbody() (full re-initialize data)
sbObjectReset() (only reset motion)
- API calls accepts time in frames now, within softbody.c it converts
Further, internally code was cleaned some (missing tabs etc). Also tried
to keep a well defined structure with hints how to add support for more
objects. Can write notes about that...
