zoomedit: Added Pixmap to drawing; added "point in polygon" checker; rooms are now selectable

1 files changed, 76 insertions, 0 deletions

diff --git a/geometry.c b/geometry.c
index 238e2fa..322deee 100644
--- a/geometry.c
+++ b/geometry.c
@@ -57,6 +57,82 @@ int vertexInRect(const VERTEX *v, const RECTANGLE *rect) {
   return ret;
 }
 
+static int quadrant(VERTEX *v) {
+  if(v->x > 0 && v->y >= 0) return 1;
+  if(v->x >= 0 && v->y < 0) return 2;
+  if(v->x < 0 && v->y <= 0) return 3;
+  if(v->x <= 0 && v->y > 0) return 4;
+  
+  return 0;
+}
+
+gboolean vertexInPolygon(const VERTEX *v, const POLYGON *p) {
+  int d = 0, i, li;
+  int q, ql, q2;
+  LINE d1 = {{-1, -1}, {1, 1}};
+  LINE d2 = {{-1, 1}, {1, -1}};
+  LINE l;
+  VERTEX v2;
+  
+  
+  if(p->nVertices == 0) return FALSE;
+  
+  v2.x = p->vertices[p->nVertices-1].x - v->x;
+  v2.y = p->vertices[p->nVertices-1].y - v->y;
+  q = quadrant(&v2);
+  
+  if(q == 0) return TRUE;
+  
+  for(i = 0; i < p->nVertices; i++) {
+    ql = q;
+    
+    v2.x = p->vertices[i].x - v->x;
+    v2.y = p->vertices[i].y - v->y;
+    q = quadrant(&v2);
+    
+    if(q == 0) return TRUE;
+    
+    switch(q-ql) {
+      case 0:
+        break;
+      case 1:
+      case -3:
+        d++;
+        break;
+      case 3:
+      case -1:
+        d--;
+        break;
+      default:
+        l.v1.x = p->vertices[(i>0)?i-1:p->nVertices-1].x - v->x;
+        l.v1.y = p->vertices[(i>0)?i-1:p->nVertices-1].y - v->y;
+        
+        l.v2 = v2;
+        
+        if(q == 1 || q == 3) {
+          if(!(lineIntersection(&l, &d2, &v2) & INTERSECTION_LINE)) return FALSE;
+          
+          q2 = quadrant(&v2);
+          if(q2 == 0) return TRUE;
+          
+          if((q == 1 && q2 == 2) || (q == 3 && q2 == 4)) d -= 2;
+          else d += 2;
+        }
+        else {
+          if(!(lineIntersection(&l, &d1, &v2) & INTERSECTION_LINE)) return FALSE;
+          
+          q2 = quadrant(&v2);
+          if(q2 == 0) return TRUE;
+          
+          if((q == 2 && q2 == 3) || (q == 4 && q2 == 1)) d -= 2;
+          else d += 2;
+        }
+    }
+  }
+  
+  return (d == 0) ? FALSE : TRUE;
+}
+
 int lineIntersection(const LINE *la, const LINE *lb, VERTEX *v) {
   double xa1 = la->v1.x, ya1 = la->v1.y;
   double xa2 = la->v2.x, ya2 = la->v2.y;