[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [14660] trunk/blender/source/blender/ blenkernel/intern/mball.c: Fix for bug #8825.

[Jiri Hnidek]

Revision: 14660
          http://projects.blender.org/plugins/scmsvn/viewcvs.php?view=rev&root=bf-blender&revision=14660
Author:   jiri
Date:     2008-05-02 14:43:46 +0200 (Fri, 02 May 2008)

Log Message:
-----------
Fix for bug #8825. find_first_point() finds first points of implicite surface in better way now. It goes 
from center of every metalement to 26 directions and try to find every place, where implicite function 
crosses zero value. Size of step is size of polygonization cube. It can be proofed, that smaller size of step 
is useless.

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

Modified: trunk/blender/source/blender/blenkernel/intern/mball.c
===================================================================
--- trunk/blender/source/blender/blenkernel/intern/mball.c	2008-05-02 12:27:05 UTC (rev 14659)
+++ trunk/blender/source/blender/blenkernel/intern/mball.c	2008-05-02 12:43:46 UTC (rev 14660)
@@ -1214,8 +1214,8 @@
 		p->y = neg.y;
 		p->z = neg.z;
 		while (1) {
+			if (i++ == RES) return;
 			p->x = 0.5f*(pos.x + neg.x);
-			if (i++ == RES) return;
 			if ((function(p->x,p->y,p->z)) > 0.0)	pos.x = p->x; else neg.x = p->x; 
 		}
 	}
@@ -1224,8 +1224,8 @@
 		p->x = neg.x;
 		p->z = neg.z;
 		while (1) {
+			if (i++ == RES) return;
 			p->y = 0.5f*(pos.y + neg.y);
-			if (i++ == RES) return;
 			if ((function(p->x,p->y,p->z)) > 0.0)	pos.y = p->y; else neg.y = p->y;
 		}
   	}
@@ -1234,8 +1234,8 @@
 		p->x = neg.x;
 		p->y = neg.y;
 		while (1) {
+			if (i++ == RES) return;
 			p->z = 0.5f*(pos.z + neg.z);
-			if (i++ == RES) return;
 			if ((function(p->x,p->y,p->z)) > 0.0)	pos.z = p->z; else neg.z = p->z;
 		}
 	}
@@ -1300,6 +1300,8 @@
 	int index[3]={1,0,-1};
 	float f =0.0f;
 	float in_v, out_v;
+	MB_POINT workp;
+	float tmp_v, workp_v, max_len, len, dx, dy, dz, nx, ny, nz, MAXN;
 
 	ml = mainb[a];
 
@@ -1360,23 +1362,49 @@
 
 					out_v = mbproc->function(out.x, out.y, out.z);
 
-					/* find "first point" on Implicit Surface of MetaElemnt ml */
-					converge(&in, &out, in_v, out_v, mbproc->function, &mbproc->start, mb, 0);
-	
-					/* indexes of CUBE, which includes "first point" */
-					c_i= (int)floor(mbproc->start.x/mbproc->size );
-					c_j= (int)floor(mbproc->start.y/mbproc->size );
-					c_k= (int)floor(mbproc->start.z/mbproc->size );
-		
-					mbproc->start.x= mbproc->start.y= mbproc->start.z= 0.0;
+					/* find "first points" on Implicit Surface of MetaElemnt ml */
+					//converge(&in, &out, in_v, out_v, mbproc->function, &mbproc->start, mb, 0);
+					workp = in;
+					workp_v = in_v;
+					max_len = sqrt((out.x-in.x)*(out.x-in.x) + (out.y-in.y)*(out.y-in.y) + (out.z-in.z)*(out.z-in.z));
 
-					/* add CUBE (with indexes c_i, c_j, c_k) to the stack,
-					 * this cube includes found point of Implicit Surface */
-					if (ml->flag & MB_NEGATIVE)
-						add_cube(mbproc, c_i, c_j, c_k, 2);
-					else
-						add_cube(mbproc, c_i, c_j, c_k, 1);
+					nx = abs((out.x - in.x)/mbproc->size);
+					ny = abs((out.y - in.y)/mbproc->size);
+					nz = abs((out.z - in.z)/mbproc->size);
+					
+					MAXN = MAX3(nx,ny,nz);
+
+					dx = (out.x - in.x)/MAXN;
+					dy = (out.y - in.y)/MAXN;
+					dz = (out.z - in.z)/MAXN;
+
+					len = 0.0;
+					while(len<=max_len) {
+						workp.x += dx;
+						workp.y += dy;
+						workp.z += dz;
+						/* compute value of implicite function */
+						tmp_v = mbproc->function(workp.x, workp.y, workp.z);
+						/* add cube to the stack, when value of implicite function crosses zero value */
+						if((tmp_v<0.0 && workp_v>=0.0)||(tmp_v>0.0 && workp_v<=0.0)) {
+
+							/* indexes of CUBE, which includes "first point" */
+							c_i= (int)floor(workp.x/mbproc->size);
+							c_j= (int)floor(workp.y/mbproc->size);
+							c_k= (int)floor(workp.z/mbproc->size);
+
+							/* add CUBE (with indexes c_i, c_j, c_k) to the stack,
+							 * this cube includes found point of Implicit Surface */
+							if (ml->flag & MB_NEGATIVE)
+								add_cube(mbproc, c_i, c_j, c_k, 2);
+							else
+								add_cube(mbproc, c_i, c_j, c_k, 1);
+						}
+						len = sqrt((workp.x-in.x)*(workp.x-in.x) + (workp.y-in.y)*(workp.y-in.y) + (workp.z-in.z)*(workp.z-in.z));
+						workp_v = tmp_v;
+					}
 						
+					mbproc->start.x= mbproc->start.y= mbproc->start.z= 0.0;
 					
 				}
 			}