[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [13881] trunk/blender/source/blender: Cloth: fixed completely useless/wrong friction force; changed some initial settings

[Daniel Genrich]

Revision: 13881
          http://projects.blender.org/plugins/scmsvn/viewcvs.php?view=rev&root=bf-blender&revision=13881
Author:   genscher
Date:     2008-02-27 04:23:17 +0100 (Wed, 27 Feb 2008)

Log Message:
-----------
Cloth: fixed completely useless/wrong friction force; changed some initial settings

Modified Paths:
--------------
    trunk/blender/source/blender/blenkernel/intern/cloth.c
    trunk/blender/source/blender/blenkernel/intern/collision.c
    trunk/blender/source/blender/src/buttons_object.c

Modified: trunk/blender/source/blender/blenkernel/intern/cloth.c
===================================================================
--- trunk/blender/source/blender/blenkernel/intern/cloth.c	2008-02-26 23:39:52 UTC (rev 13880)
+++ trunk/blender/source/blender/blenkernel/intern/cloth.c	2008-02-27 03:23:17 UTC (rev 13881)
@@ -184,7 +184,7 @@
 	clmd->sim_parms->maxgoal = 1.0f;
 	clmd->sim_parms->mingoal = 0.0f;
 	clmd->sim_parms->defgoal = 0.0f;
-	clmd->sim_parms->goalspring = 10.0f;
+	clmd->sim_parms->goalspring = 1.0f;
 	clmd->sim_parms->goalfrict = 5.0f;
 }
 

Modified: trunk/blender/source/blender/blenkernel/intern/collision.c
===================================================================
--- trunk/blender/source/blender/blenkernel/intern/collision.c	2008-02-26 23:39:52 UTC (rev 13880)
+++ trunk/blender/source/blender/blenkernel/intern/collision.c	2008-02-27 03:23:17 UTC (rev 13881)
@@ -492,33 +492,27 @@
 		if(magrelVel < -ALMOST_ZERO) 
 		{
 			// Calculate Impulse magnitude to stop all motion in normal direction.
-			float tangential[3], magtangent;
+			float magtangent;
 			double impulse = 0.0;
 			float vrel_t_pre[3];
-			float vrel_t[3], temp[3];
+			float temp[3];
 			
 			// calculate tangential velocity
 			VECCOPY(temp, collpair->normal);
 			VecMulf(temp, magrelVel);
 			VECSUB(vrel_t_pre, relativeVelocity, temp);
 			
-			VECCOPY(vrel_t, vrel_t_pre);
+			magtangent = INPR(vrel_t_pre,vrel_t_pre) - MIN2(clmd->coll_parms->friction * 0.01 * magrelVel,INPR(vrel_t_pre,vrel_t_pre));
 			
-			VecMulf(vrel_t, MAX2(1.0 - (clmd->coll_parms->friction * magrelVel / sqrt(INPR(vrel_t_pre,vrel_t_pre))), 0.0));
-			
-			VECSUB(tangential, vrel_t_pre, vrel_t);
-			VecMulf(tangential, 0.5);
-			
-			magtangent = INPR(tangential, tangential);
-			
 			// Apply friction impulse.
 			if (magtangent > ALMOST_ZERO) 
-			{
-				impulse = magtangent / ( 1.0 + w1*w1 + w2*w2 + w3*w3);
-				magtangent = sqrt(magtangent);
-				VECADDMUL(cloth1->verts[collpair->ap1].impulse, tangential, w1 * impulse/magtangent);
-				VECADDMUL(cloth1->verts[collpair->ap2].impulse, tangential, w2 * impulse/magtangent);
-				VECADDMUL(cloth1->verts[collpair->ap3].impulse, tangential, w3 * impulse/magtangent);
+			{	
+				Normalize(vrel_t_pre);
+
+				impulse = -2.0 * magtangent / ( 1.0 + w1*w1 + w2*w2 + w3*w3);
+				VECADDMUL(cloth1->verts[collpair->ap1].impulse, vrel_t_pre, w1 * impulse);
+				VECADDMUL(cloth1->verts[collpair->ap2].impulse, vrel_t_pre, w2 * impulse);
+				VECADDMUL(cloth1->verts[collpair->ap3].impulse, vrel_t_pre, w3 * impulse);
 			}
 			
 

Modified: trunk/blender/source/blender/src/buttons_object.c
===================================================================
--- trunk/blender/source/blender/src/buttons_object.c	2008-02-26 23:39:52 UTC (rev 13880)
+++ trunk/blender/source/blender/src/buttons_object.c	2008-02-27 03:23:17 UTC (rev 13881)
@@ -5221,7 +5221,7 @@
 				MEM_freeN (clvg2);
 			}
 			
-			uiDefButF(block, NUM, B_CLOTH_RENEW, "Pin Stiff:", 10,50,150,20, &clmd->sim_parms->goalspring, 0.0, 500.0, 10, 0, "Pin (vertex target position) spring stiffness");
+			uiDefButF(block, NUM, B_CLOTH_RENEW, "Pin Stiff:", 10,50,150,20, &clmd->sim_parms->goalspring, 0.0, 50.0, 50, 0, "Pin (vertex target position) spring stiffness");
 			uiDefBut(block, LABEL, 0, "",160,50,150,20, NULL, 0.0, 0, 0, 0, "");	
 			// uiDefButI(block, NUM, B_CLOTH_RENEW, "Pin Damp:", 160,50,150,20, &clmd->sim_parms->goalfrict, 1.0, 100.0, 10, 0, "Pined damping (higher = doesn't oszilate so much)");
 			/*
@@ -5335,7 +5335,7 @@
 		{
 			uiDefButF(block, NUM, REDRAWBUTSOBJECT, "Min Distance:",	   160,60,150,20, &clmd->coll_parms->epsilon, 0.001f, 1.0, 0.01f, 0, "Minimum distance between collision objects before collision response takes in, can be changed for each frame");
 			uiDefButS(block, NUM, REDRAWBUTSOBJECT, "Collision Quality:",	   10,40,150,20, &clmd->coll_parms->loop_count, 1.0, 20.0, 1.0, 0, "How many collision iterations should be done. (higher = better = slower), can be changed for each frame");
-			uiDefButF(block, NUM, REDRAWBUTSOBJECT, "Friction:",	   160,40,150,20, &clmd->coll_parms->friction, 0.0, 10.0, 1.0, 0, "Friction force if a collision happened (high=slower movement when collided)");
+			uiDefButF(block, NUM, REDRAWBUTSOBJECT, "Friction:",	   160,40,150,20, &clmd->coll_parms->friction, 0.0, 80.0, 1.0, 0, "Friction force if a collision happened (0=movement not changed, 100=no movement left)");
 			
 			uiDefButBitI(block, TOG, CLOTH_COLLSETTINGS_FLAG_SELF, B_CLOTH_RENEW, "Enable selfcollisions",	10,20,150,20, &clmd->coll_parms->flags, 0, 0, 0, 0, "Enable selfcollisions with this object");
 			if (clmd->coll_parms->flags & CLOTH_COLLSETTINGS_FLAG_SELF)