- 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.
Particle point cache can now be loaded from external files.
- Activated by "external" checkbox in cache panel and giving proper folder path and file name identifier.
- External cache panel has controls for particle emission start, end, lifetime and random lifetime. These should be set according to the external data for correct playback.
- External files should be named "identifier_frame_index.bphys" or "identifier_frame.bphys" where:
* "identifier" is a freely choseable name.
* "frame" is the cached frame number.
** Six digits padded with zeros!, for example "000024".
* "index" can be used to tell caches with the same identifier apart.
** Two digits starting from zero.
** The index and the underscore before are optional. If no index is present the index number in ui should be set to -1.
- Cache file format is pure floating point numbers (in binary, not text!) with each particle's data one after the other with the following data members:
* 3 floats: particle's location vector
* 3 floats: particle's velocity vector (per second)
* 4 floats: particle's rotation quaternion
* 3 floats: particle's angular velocity vector (per second)
* 1 float: frame of the actual data (this can be non-integer for particles that are born or die between two integer frames, but otherwise should be the same as the "frame" in the file name)
- Cache files don't have to exist for each frame.
* Frames without actual data are interpolated from surrounding frames that have data (extrapolation is not supported).
- Cache file formats with extended (or reduced even) data members are in future plans for easier usage.
- Current code only does particles, don't yet know if it's applicable to cloth or sb.
- Known issue: endianness can't yet be handled in any way.
Other changes:
New hard limits for many particle parameters. Some examples:
- Maximum amount of particles: 10M particles :) And before you all go and crash your Blender trying this out remember that this limit is only for those freaks who really have the machine power to handle it. 10M particles alone take around 2.2 Gb of memory / disk space in saved file and each cached frame takes around 0.5 Gb of memory / disk space depending on cache mode.
* Known issue: To actually use this many particles they most likely need to be allocated in parts as taking hold of a 2.2Gb chunk of memory at once is probably not ok with any operating system.
- Maximum amount of children: 100k children/particle (1T childparticles here we come :D)
- Kink frequency: -100k to 100k half-rotations (really strange the previous limit was only from zero upwards)
- Path draw steps: 10 (power of 2 remember)
- Path render steps: 20 (power of 2 also!! If over 1M segments doesn't get you smooth paths then I think nothing will!)
Too many new features to list! But here are the biggies:
- Boids can move on air and/or land, or climb a goal object.
- Proper interaction with collision objects.
* Closest collision object in negative z direction is considered as ground.
* Other collision objects are obstacles and boids collide with them.
- Boid behavior rules are now added to a dynamic list.
* Many new rules and many still not implemented.
* Different rule evaluation modes (fuzzy, random, average).
- Only particle systems defined by per system "boid relations" are considered for simulation of that system.
* This is in addition to the boids own system of course.
* Relations define other systems as "neutral", "friend" or "enemy".
- All effectors now effect boid physics, not boid brains.
* This allows forcing boids somewhere.
* Exception to this is new "boid" effector, which defines boid predators (positive strength) and goals (negative strength).
Known issue:
- Boid health isn't yet stored in pointcache so simulations with "fight" rule are not be read from cache properly.
- Object/Group visualization object's animation is not played in "particle time". This is definately the wanted behavior, but isn't possible with the current state of dupliobject code.
Other new features:
- Particle systems can now be named separately from particle settings.
* Default name for particle settings is now "ParticleSettings" instead of "PSys"
- Per particle system list of particle effector weights.
* Enables different effection strengths for particles from different particle systems with without messing around with effector group setting.
Other code changes:
- KDTree now supports range search as it's needed for new boids.
- "Keyed particle targets" renamed as general "particle targets", as they're needed for boids too. (this might break some files saved with new keyed particles)
Bug fixes:
- Object & group visualizations didn't work.
- Interpolating pointcache didn't do rotation.
this works for the calling operators from python and using the RNA api.
bpy.ops.CONSOLE_exec() is now bpy.ops.console.exec()
eg.
split.itemO("PARTICLE_OT_editable_set", text="Free Edit") becomes... split.itemO("particle.editable_set", text="Free Edit")
For now any operator thats called checks if its missing _OT_ and assumes its python syntax and converts it before doing the lookup.
bpy.ops is a python class in release/ui/bpy_ops.py which does the fake submodules and conversion, the C operator api is at bpy.__ops__
personally Id still rather rename C id-names not to contain the _OT_ text which would avoid the conversion, its called a lot since the UI has to convert the operators.
- Keyed targets in one list instead of "chaining", this opens up many more possibilities than before and is much less obscure.
- Better keyed timing possibilities (time & duration in frames).
- Looping over keyed targets list.
Other changes:
- New child setting "length" with threshold (great for guard & underfur with a single particle system)
- Modularization of path interpolation code.
- Cleared "animateable" flags from many particle settings that shouldn't be animateable.
Fixes:
- Keyed particles weren't copied properly (ancient bug).
- Hair rotations depended on global z-axis for root rotation so downward facing strands could flip rotation randomly. Now initial hair rotation is derived from face dependent hair matrix. (This caused for example ugly flipping of child strands on some cases).
- Children from faces weren't calculated straight after activating them.
- Multiple disk cache fixes:
* Disk cache didn't work correctly with frame steps.
* Conversion from memory cache to disk cache didn't work with cloth.
* Disk cache crashed on some frames trying to close an already closed cache file.
* Trails didn't work with disk cached particles.
- Child rough effects were effected by emitter object loc/rot making them next to useless with animation, why didn't anybody tell me this!!
- Lots of random code cleanup.
"moving the ID browser into its own panel. Eventually these panels should loose their headers to distinguish them from other, normal panels. Also a few other fixes for bones and armature panels."
* Baked normal particles can now use the "Path" visualization.
* Path "max length" & "abs length" are now history:
- New option to set path start & end times + random variation to length.
- Much more flexible (and calculated better) than previous options.
- This works with parents, children, hair & normal particles unlike old length option.
- Only known issue for now is that children from faces don't get calculated correctly when using path start time.
* New option "trails" for "halo", "line" and "billboard" visualizations:
- Draws user controllable number of particle instances along particles path backwards from current position.
- Works with children too for cool/weird visualizations that weren't possible before.
* Normal particle children's velocities are now approximated better when needed so that "line" visualization trails will look nice.
* New particle instance modifier options:
- "path"-option works better and has controllable (max)position along path (with random variation possible).
- "keep shape"-option for hair, keyed, or baked particles allows to place the instances to a single point (with random variation possible) along particle path.
- "axis" option to make rotation handling better (still not perfect, but will have to do for now).
Some fixes & cleanup done along the way:
* Random path length didn't work for non-child particles.
* Cached & unborn particles weren't reset to emit locations.
* Particle numbers weren't drawn in the correct place.
* Setting proper render & draw visualizations was lost somewhere when initializing new particle settings.
* Changing child mode wasn't working correctly.
* Some cleanup & modularization of particle child effector code and particle drawing & rendering code.
* Object & group visualizations didn't work.
* Child simplification didn't work.
RNA
* Added the relevant active_*_index properties, with proper
get/set/range, updates and notifiers.
* Context.tool_settings.
* ToolSettings.vertex_group_weight.
Operators
* MESH_OT_uv_texture_add/remove
* MESH_OT_vertex_color_add/remove
* MESH_OT_sticky_add/remove
* OBJECT_OT_vertex_group_add/remove/assign/remove_from/
select/deselect/copy/copy_to_linked
* OBJECT_OT_shape_key_add/remove
UI
* Some updates and cleanups in list template code.
Known issue: when going in & out of editmode, uv textures and vertex
colors dissappear. I thought me->edit_mesh would be NULL when not in
edit mode but it is not?
Image Window
* Unpack operator now works.
* Some small layout code tweaks.
Info Window Header
* Moved to python UI code.
* template_running_jobs, template_operator_search added.
* Ported external data operators: pack/unpack all, make
paths relative/absolute, find/report missing files.
Also
* Report RPT_INFO too, not only warnings and errors.
* Run UI handle functions after RNA and Operators.
* Rename particle system add/remove operators, to not
include "slot", that's only there for materials because
that's what they are called now in RNA.
* Adding/removing particle systems to an object.
* Changing of particle settings.
* Currently showing an object's particle systems in a list (like materials).
* Based on what happens during simulation the cache is marked (also in cache panel, this could possibly be extended to 3d view as well) as:
- exact (not marked)
- outdated (simulation is not done completely with current settings)
- non-exact (frames were skipped during simulation)
* The parameter "cache step" effects the number of frames between saved cache frames.
- This can save a lot of memory (or disk space) if absolutely frame accurate simulation is not required.
- Speeds up the "quick caching" very much.
- Frames between cached frames are interpolated from the cached frames.
- Current default value of 10 frames works nicely with up/down-arrows (skip 10 frames forwards/backwards on timeline), but can be changed if wanted.
* The caching can work in normal or "quick" mode:
[Normal cache]
- Basic: Calculate what even happens (settings change, big frame steps etc.) and cache results, if possible try to use "cache step" when saving cache frames.
- Becomes non-exact: After larger than 1 frame steps.
- Becomes outdated: After any change effecting the simulation other than frame steps.
- Pros/cons: Freedom of doing anything and playing with particles, but exact results have to calculated from the beginning.
[Quick cache]
- Basic: Calculate simulation up to current frame automatically on changes with cache step sized jumps in simulation. With multiple "quick cached" simulations the smallest cache step is used.
- Becomes non-exact: Always from frame 1 (unless cache step = 1).
- Becomes outdated: Never.
- Pros/cons: Not very accurate, but super fast!
- Todo: Transform of any animated (non-autokeyed) object is locked! Probably needs some tinkering with anim sys overrides.
* The simulation can be run forwards or backwards even if it's cache is outdated or non-exact, the following rules apply in these situations:
- step forwards (to unknown) -> simulate from last exact frame, store result
- step backwards (to known) -> result is interpolated from existing frames, store result, clear cache forwards if current frame is after last exact frame
* "Calculate to current frame" runs the simulation from start to current frame with a frame steps of 1.
- Baking does the same, but runs the simulation all the way to the end of simulation.
- Rendering does this automatically if the simulation is outdated of non-exact, so all rendered simulations will always be updated and exact.
* Every cache panel also holds buttons to "Bake all dynamics", "Free all dynamics" and "Update all dynamics to current frame".
* Cloth simulation supports the new cache too.
* Allows moving, rotating & scaling of particle simulations.
* Setting in particle render options.
* Changes viewed & rendered particles from global space to parent space.
* Doesn't effect simulations at all.
* Particles support larger than 1 frame changes, bigger frame changes can result in inaccurate results, but it's super fast and you get a nice feeling of how the particles behave!
* "Cache to current frame" button calculates the exact result of particles at current frame.
* Current state of cache can be protected by making it a bake.
* Cache is now in memory by default, disk cache is an option.
* Only "viewport %" number of particles are calculated and cached in viewport, baking and rendering calculate all particles.
* Info on cached frames and memory usage given in ui.
* Support for exact "autocaching" of changes and large frame changes(disabled for now until exact place in event system is decided)
* "Continue physics" is probably deprecated after this and should be removed once sb & cloth use the new cache code.
Todo:
* Make softbody & cloth use the new cache things.
Other changes:
* Some cleanup of particle buttons.
* Context now allows pinning a datablock, independent of
selection.
* Initial ID browse buttons for most buttons tabs.
* Browsing from world to texture now displays world textures
again, but is a bit of a hack, not sure there is a right
way to do this.
* There's a button to switch between active materials and
textures now, only temporary though.
* There's some code to put context part in own region,
disabled still because it doesn't work that well yet.
* Added a constraint tab in the buttons window.
* Added more sequencer buttons (effect strips).
Note: Sequencer buttons will go into the sequencer itself (n-key Panel) later.
* Particle button tweaks by William Reynish. Thanks!
* Some RNA fixes and new properties.
-Many things not yet working properly :)
-Experimental new (hopefully more logical) categorization of buttons, feedback on this is very welcome.
-Separate render & draw types, for example now there is actually a render option "halo" instead of all the different point draw types.
-Particles get recalculated only from buttons that actually change something that has to be recalculated, for example changing visualization doesn't reset particles any more.
-Boid physics buttons are still missing as I'm currently redoing the whole boids code.
-Point caching is still very wip, so baking is not possible for example, but I added a few cache baking flags for rna that were/will be needed for particle buttons logic.
