zoomedit: Implemented geometry functions.

1 files changed, 50 insertions, 0 deletions

diff --git a/geometry.h b/geometry.h
new file mode 100644
index 0000000..c936e59
--- /dev/null
+++ b/geometry.h
@@ -0,0 +1,50 @@
+#ifndef GEOMETRY_H_
+#define GEOMETRY_H_
+
+
+#define EDGE_NONE        0
+#define EDGE_LEFT   (1<<0)
+#define EDGE_RIGHT  (1<<1)
+#define EDGE_TOP    (1<<2)
+#define EDGE_BOTTOM (1<<3)
+#define EDGE_ALL    (EDGE_LEFT|EDGE_RIGHT|EDGE_TOP|EDGE_BOTTOM)
+
+#define INTERSECTION_ERROR          -1
+#define INTERSECTION_NONE            0
+#define INTERSECTION_IDENTICAL       1
+#define INTERSECTION_LINE_LINE       2
+#define INTERSECTION_LINE_SEGMENT    3
+#define INTERSECTION_SEGMENT_LINE    4
+#define INTERSECTION_SEGMENT_SEGMENT 5
+
+
+typedef struct _VERTEX {
+  double x, y;
+} VERTEX;
+
+typedef struct _RECTANGLE {
+  double x, y, width, height;
+} RECTANGLE;
+
+typedef struct _LINE {
+  VERTEX v1, v2;
+} LINE;
+
+typedef struct _VERTEX_LIST {
+  unsigned int nVertices;
+  VERTEX *vertices;
+} VERTEX_LIST, POLYGON;
+
+
+void addVertex(VERTEX_LIST *list, VERTEX *v);
+void insertVertex(VERTEX_LIST *list, VERTEX *v, unsigned int n);
+void deleteVertex(VERTEX_LIST *list, unsigned int n);
+
+
+int vertexInRect(const VERTEX *v, const RECTANGLE *rect);
+int lineIntersection(const LINE *la, const LINE *lb, VERTEX *v);
+int lineRectIntersection(const LINE *l, const RECTANGLE *rect, int edge, VERTEX *v);
+int lineRectIntersections(const LINE *line, const RECTANGLE *rect, int edge, VERTEX *v1, VERTEX *v2);
+void simplifyPolygon(const POLYGON *in, const RECTANGLE *rect, POLYGON *out);
+
+#endif /*GEOMETRY_H_*/