A bunch of fun stuff now possible because of new pointcache code:

* 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.

1 files changed, 3 insertions, 2 deletions

diff --git a/source/blender/blenkernel/BKE_particle.h b/source/blender/blenkernel/BKE_particle.h
index 73f0195d1d8..aa24706077d 100644
--- a/source/blender/blenkernel/BKE_particle.h
+++ b/source/blender/blenkernel/BKE_particle.h
@@ -91,7 +91,8 @@ typedef struct ParticleTexture{
 	float ivel;							/* used in reset */
 	float time, life, exist, size;		/* used in init */
 	float pvel[3];						/* used in physics */
-	float length, clump, kink, rough;	/* used in path caching */
+	float length, clump, kink, effector;/* used in path caching */
+	float rough1, rough2, roughe;		/* used in path caching */
 } ParticleTexture;
 
 typedef struct BoidVecFunc{
@@ -270,7 +271,7 @@ void psys_update_world_cos(struct Object *ob, struct ParticleSystem *psys);
 int do_guide(struct Scene *scene, struct ParticleKey *state, int pa_num, float time, struct ListBase *lb);
 float psys_get_size(struct Object *ob, struct Material *ma, struct ParticleSystemModifierData *psmd, struct IpoCurve *icu_size, struct ParticleSystem *psys, struct ParticleSettings *part, struct ParticleData *pa, float *vg_size);
 float psys_get_timestep(struct ParticleSettings *part);
-float psys_get_child_time(struct ParticleSystem *psys, struct ChildParticle *cpa, float cfra);
+float psys_get_child_time(struct ParticleSystem *psys, struct ChildParticle *cpa, float cfra, float *birthtime, float *dietime);
 float psys_get_child_size(struct ParticleSystem *psys, struct ChildParticle *cpa, float cfra, float *pa_time);
 void psys_get_particle_on_path(struct Scene *scene, struct Object *ob, struct ParticleSystem *psys, int pa_num, struct ParticleKey *state, int vel);
 int psys_get_particle_state(struct Scene *scene, struct Object *ob, struct ParticleSystem *psys, int p, struct ParticleKey *state, int always);