worked on 3D walls

geo/GPCPolygon2.h

@@ -2,6 +2,8 @@
 #define GPCPOLYGON2_H
 
 #include "../lib/gpc/gpc.cpp.h"
+#include "Polygon2.h"
+#include "Triangle3.h"
 
 class GPCPolygon2 {
 
@@ -44,6 +46,11 @@ public:
 		;
 	}
 
+	void add(const Polygon2& poly) {
+		GPCPolygon cur;
+		toGPC(poly, cur);
+		gpc_polygon_clip(GPC_UNION, &state, &cur, &state);
+	}
 	void add(const Floorplan::Polygon2& poly) {
 		GPCPolygon cur;
 		toGPC(poly, cur);
@@ -55,6 +62,11 @@ public:
 		toGPC(poly, cur);
 		gpc_polygon_clip(GPC_DIFF, &state, &cur, &state);
 	}
+	void remove(const Polygon2& poly) {
+		GPCPolygon cur;
+		toGPC(poly, cur);
+		gpc_polygon_clip(GPC_DIFF, &state, &cur, &state);
+	}
 
 	std::vector<std::vector<Point3>> get() {
 
@@ -88,6 +100,57 @@ public:
 
 	}
 
+	std::vector<Triangle3> getTriangles() {
+
+		gpc_tristrip res;
+		res.num_strips = 0;
+		res.strip = nullptr;
+
+		//res.strip = (gpc_vertex_list*) malloc(1024);
+		gpc_polygon_to_tristrip(&state, &res);
+
+		std::vector<Triangle3> trias;
+
+		for (int i = 0; i < res.num_strips; ++i) {
+			gpc_vertex_list lst = res.strip[i];
+			for (int j = 2; j < lst.num_vertices; ++j) {
+
+				gpc_vertex& v1 = lst.vertex[j - 2];
+				gpc_vertex& v2 = lst.vertex[j - 1];
+				gpc_vertex& v3 = lst.vertex[j];
+
+				// https://en.wikipedia.org/wiki/Triangle_strip
+				// GL_TRIANGLE_STRIP
+				// Draws a series of triangles (three-sided polygons) using vertices v0, v1, v2, then v2, v1, v3 (note the order), then v2, v3, v4, and so on. The ordering is to ensure that the triangles are all drawn with the same orientation so that the strip can correctly form part of a surface.
+				// For odd n, vertices n, n+1, and n+2 define triangle n. For even n, vertices n+1, n, and n+2 define triangle n. N-2 triangles are drawn.
+
+				if (j % 2 == 0) {
+					Triangle3 tria(
+						Point3(v1.x, v1.y, z),
+						Point3(v2.x, v2.y, z),
+						Point3(v3.x, v3.y, z)
+					);
+					trias.push_back(tria);
+				} else {
+					Triangle3 tria(
+						Point3(v2.x, v2.y, z),
+						Point3(v1.x, v1.y, z),
+						Point3(v3.x, v3.y, z)
+					);
+					trias.push_back(tria);
+				}
+
+
+			}
+
+		}
+
+		gpc_free_tristrip(&res);
+
+		return std::move(trias);
+
+	}
+
 	std::vector<std::vector<Point3>> get(float z) {
 
 		gpc_tristrip res;
@@ -118,7 +181,7 @@ public:
 
 private:
 
-	void toGPC(Floorplan::Polygon2 poly, GPCPolygon& result) {
+	void toGPC(const Floorplan::Polygon2& poly, GPCPolygon& result) {
 
 		std::vector<gpc_vertex> verts;
 		for (Point2 p2 : poly.points) {
@@ -133,5 +196,20 @@ private:
 
 	}
 
+	void toGPC(const Polygon2& poly, GPCPolygon& result) {
+
+		std::vector<gpc_vertex> verts;
+		for (Point2 p2 : poly) {
+			gpc_vertex vert; vert.x = p2.x; vert.y = p2.y;
+			verts.push_back(vert);
+		}
+
+		gpc_vertex_list list;
+		list.num_vertices = verts.size();
+		list.vertex = verts.data();
+		gpc_add_contour(&result, &list, 0);
+
+	}
+
 };
 #endif