[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [16578] trunk/blender/source/blender/ blenkernel/intern/particle.c: Fix for [#17642] Particule Hair - Vertex Group lenght don't works without Children

[Janne Karhu]

Revision: 16578
          http://projects.blender.org/plugins/scmsvn/viewcvs.php?view=rev&root=bf-blender&revision=16578
Author:   jhk
Date:     2008-09-17 21:29:44 +0200 (Wed, 17 Sep 2008)

Log Message:
-----------
Fix for [#17642] Particule Hair - Vertex Group lenght don't works without Children
- This feature had been removed from the code! So this is how things work now:
For normal (non-child) hair particles the length vgroup is used if we're not in particle edit mode and if there are no child particles. So for example checking "Parents" in the visualization panel when children are in use will result in full length parent strands, this is a feature so that you can see how the parent's go to predict child behavior better, not a bug :)

Modified Paths:
--------------
    trunk/blender/source/blender/blenkernel/intern/particle.c

Modified: trunk/blender/source/blender/blenkernel/intern/particle.c
===================================================================
--- trunk/blender/source/blender/blenkernel/intern/particle.c	2008-09-17 17:59:29 UTC (rev 16577)
+++ trunk/blender/source/blender/blenkernel/intern/particle.c	2008-09-17 19:29:44 UTC (rev 16578)
@@ -1775,37 +1775,17 @@
 static int check_path_length(int k, ParticleCacheKey *keys, ParticleCacheKey *state, float max_length, float *cur_length, float length, float *dvec)
 {
 	if(*cur_length + length > max_length){
-		//if(p<totparent){
-		//	if(k<=(int)cache[totpart+p]->time){
-		//		/* parents need to be calculated fully first so that they don't mess up their children */
-		//		/* we'll make a note of where we got to though so that they're easy to finish later */
-		//		state->time=(max_length-*cur_length)/length;
-		//		cache[totpart+p]->time=(float)k;
-		//	}
-		//}
-		//else{
 		VecMulf(dvec, (max_length - *cur_length) / length);
 		VECADD(state->co, (state - 1)->co, dvec);
 		keys->steps = k;
 		/* something over the maximum step value */
 		return k=100000;
-		//}
 	}
 	else {
 		*cur_length+=length;
 		return k;
 	}
 }
-static void finalize_path_length(ParticleCacheKey *keys)
-{
-	ParticleCacheKey *state = keys;
-	float dvec[3];
-	state += state->steps;
-
-	VECSUB(dvec, state->co, (state - 1)->co);
-	VecMulf(dvec, state->steps);
-	VECADD(state->co, (state - 1)->co, dvec);
-}
 static void offset_child(ChildParticle *cpa, ParticleKey *par, ParticleKey *child, float flat, float radius)
 {
 	VECCOPY(child->co,cpa->fuv);
@@ -1986,7 +1966,7 @@
 	ParticleCacheKey **cache= psys->childcache;
 	ParticleCacheKey **pcache= psys->pathcache;
 	ParticleCacheKey *state, *par = NULL, *key[4];
-	ParticleData *pa;
+	ParticleData *pa=NULL;
 	ParticleTexture ptex;
 	float *cpa_fuv=0;
 	float co[3], orco[3], ornor[3], t, rough_t, cpa_1st[3], dvec[3];
@@ -2287,10 +2267,6 @@
 			get_strand_normal(ctx->ma, ornor, cur_length, state->vel);
 		}
 	}
-
-	/* now let's finalise the interpolated parents that we might have left half done before */
-	if(i<ctx->totparent)
-		finalize_path_length(keys);
 }
 
 void *exec_child_path_cache(void *data)
@@ -2364,6 +2340,7 @@
 	ParticleCacheKey *ca, **cache=psys->pathcache;
 	ParticleSystemModifierData *psmd = psys_get_modifier(ob, psys);
 	ParticleEditSettings *pset = &G.scene->toolsettings->particle;
+	ParticleSettings *part = psys->part;
 	
 	ParticleData *pa;
 	ParticleKey keys[4], result, *kkey[2] = {NULL, NULL};
@@ -2389,6 +2366,8 @@
 	float nosel_col[3];
 	float length, vec[3];
 	float *vg_effector= NULL, effector=0.0f;
+	float *vg_length= NULL, pa_length=1.0f, max_length=1.0f, cur_length=0.0f;
+	float len, dvec[3];
 
 	/* we don't have anything valid to create paths from so let's quit here */
 	if((psys->flag & PSYS_HAIR_DONE)==0 && (psys->flag & PSYS_KEYED)==0)
@@ -2440,6 +2419,9 @@
 	if(psys->part->from!=PART_FROM_PARTICLE) {
 		if(!(psys->part->flag & PART_CHILD_EFFECT))
 			vg_effector = psys_cache_vgroup(psmd->dm, psys, PSYS_VG_EFFECTOR);
+		
+		if(!edit && !psys->totchild)
+			vg_length = psys_cache_vgroup(psmd->dm, psys, PSYS_VG_LENGTH);
 	}
 
 	/*---first main loop: create all actual particles' paths---*/
@@ -2453,6 +2435,12 @@
 		if(editupdate && !(pa->flag & PARS_EDIT_RECALC)) continue;
 		else memset(cache[i], 0, sizeof(*cache[i])*(steps+1));
 
+		if(!edit && !psys->totchild) {
+			pa_length = part->length * (1.0f - part->randlength*pa->r_ave[0]);
+			if(vg_length)
+				pa_length *= psys_interpolate_value_from_verts(psmd->dm,part->from,pa->num,pa->fuv,vg_length);
+		}
+
 		cache[i]->steps = steps;
 
 		if(edit)
@@ -2678,6 +2666,27 @@
 
 			}
 
+			if(!edit && !psys->totchild) {
+				/* check if path needs to be cut before actual end of data points */
+				if(k){
+					VECSUB(dvec,ca->co,(ca-1)->co);
+					if(part->flag&PART_ABS_LENGTH)
+						len=VecLength(dvec);
+					else
+						len=1.0f/(float)steps;
+
+					k=check_path_length(k,cache[i],ca,max_length,&cur_length,len,dvec);
+				}
+				else{
+					/* initialize length calculation */
+					if(part->flag&PART_ABS_LENGTH)
+						max_length= part->abslength*pa_length;
+					else
+						max_length= pa_length;
+
+					cur_length= 0.0f;
+				}
+			}
 		}
 	}
 
@@ -2690,6 +2699,9 @@
 
 	if(vg_effector)
 		MEM_freeN(vg_effector);
+
+	if(vg_length)
+		MEM_freeN(vg_length);
 }
 /************************************************/
 /*			Particle Key handling				*/