foo

diff --git a/src/frac.c b/src/frac.c
index 071b5c2..93cb963 100644 (file)
--- a/src/frac.c
+++ b/src/frac.c
@@ -118,29 +118,68 @@ int frac_build_cells(struct fracture *frac)
 
 static int build_cell(struct fracture *frac, int cellidx)
 {
-       int i, j, num;
-       struct plane plane, *pptr;
+       int i, j, num, clipres;
+       struct plane plane;
        struct frac_cell *cell = frac->cells + cellidx;
+       struct poly poly, clipped, *polys, *pptr;
+       float bsize;
+
+       if(!(polys = dynarr_alloc(0, sizeof *polys))) {
+               return -1;
+       }
+
+       cmesh_bsphere(frac->mesh, 0, &bsize);
+       size *= 2;
 
        num = dynarr_size(frac->cells);
        for(i=0; i<num; i++) {
                if(i == cellidx) continue;
                midplane(&plane, &cell->pt, &frac->cells[i].pt);
-               if(!(pptr = dynarr_push(cell->planes, &plane))) {
+               plane_poly(&plane, &poly, bsize);
+               if(!(pptr = dynarr_push(polys, &poly))) {
                        return -1;
                }
-               cell->planes = pptr;
+               polys = pptr;
        }
 
+       num = dynarr_size(polys);
+       valid_planes = alloca(num * sizeof *valid_planes);
+       memset(valid_planes, 0xff, num * sizeof *valid_planes);
+
        /* clip all planes against each other to end up with a convex cell */
-       num = dynarr_size(cell->planes);
+       cell->num_polys = num;
        for(i=0; i<num; i++) {
                for(j=0; j<num; j++) {
-                       if(i == j) continue;
+                       if(i == j || !valid_planes[j]) {
+                               continue;
+                       }
+
+                       /* clip plane polygon i with plane j */
+                       poly_plane(polys + j, &plane);
+                       init_poly(&clipped);
+                       if((clipres = clip_poly(&clipped, polys + i, &plane)) < 0) {
+                               /* completely clipped, mark it for removal */
+                               valid_planes[i] = 0;
+                               cell->num_polys--;
+                               break;
+                       }
+               }
+       }
 
-                       clip_poly...
+       if(!(cell->polys = malloc(cell->num_polys * sizeof *cell->polys))) {
+               return -1;
+       }
+       pptr = cell->polys;
+       for(i=0; i<num; i++) {
+               if(valid_planes[i]) {
+                       assert(pptr - cell->polys < cell->num_polys);
+                       *pptr++ = polys[i];
+               } else {
+                       destroy_poly(polys + i);
                }
        }
+       darr_free(polys);
+       return 0;
 }
 
 int frac_build_shell(struct fracture *frac)

diff --git a/src/frac.h b/src/frac.h
index 72192b7..8a7e022 100644 (file)
--- a/src/frac.h
+++ b/src/frac.h
@@ -7,8 +7,8 @@
 
 struct frac_cell {
        cgm_vec3 pt;
-       struct cmesh *mesh;
-       struct plane *planes;                   /* dynarr */
+       struct poly *polys;
+       int num_polys;
 };
 
 struct fracture {

diff --git a/src/geom.c b/src/geom.c
index 81e9df4..4e30628 100644 (file)
--- a/src/geom.c
+++ b/src/geom.c
@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include <assert.h>
 #include "geom.h"
 #include "dynarr.h"
 
@@ -130,6 +131,12 @@ float ray_poly(const cgm_ray *ray, const struct poly *poly)
        return t;
 }
 
+int init_poly(struct poly *p)
+{
+       p->verts = dynarr_alloc(0, sizeof *p->verts);
+       assert(p->verts);
+       return p->verts ? 0 : -1;
+}
 
 /* returns:
  *  1 -> both inside

diff --git a/src/geom.h b/src/geom.h
index ebb6659..19c10ff 100644 (file)
--- a/src/geom.h
+++ b/src/geom.h
@@ -27,6 +27,8 @@ int plane_poly(const struct plane *plane, struct poly *poly, float size);
 float ray_plane(const cgm_ray *ray, const struct plane *plane);
 float ray_poly(const cgm_ray *ray, const struct poly *poly);
 
+int init_poly(struct poly *p);
+void destroy_poly(struct poly *p);
 int clip_poly(struct poly *pout, const struct poly *pin, const struct plane *plane);
 
 #endif /* GEOM_H_ */