ENGINES: Insert loop for ray-casting algorithm

src/engines/aurora/trigger.cpp

@@ -59,21 +59,26 @@ bool Trigger::contains(float x, float y) const {
 	if (!_boundingbox.isIn(x, y))
 		return false;
 
-	glm::vec3 orig(x, y, 1000);
-	glm::vec3 intersection;
-
-	for (size_t i = 2; i < vertexCount; ++i) {
-		if (glm::intersectRayTriangle(orig,
-					glm::vec3(0, 0, -1),
-					_geometry[0],
-					_geometry[i - 1],
-					_geometry[i],
-					intersection) == 1) {
-			return true;
-		}
+	// Initialization
+	std::vector<glm::vec3>::const_iterator it1, it2;
+	int count = 0;
+
+	// Set first iterator to the last vertex
+	it1 = _geometry.end();
+	it1--;
+
+	// Cycle through the vertices, counting the number of ray intersections
+	for (it2 = _geometry.begin(); it2 != _geometry.end(); ++it2) {
+		// Check for a ray intersection
+		if (isRayIntersect(x, y, it1->x, it1->y, it2->x, it2->y))
+			count++;
+
+		// Store for the next loop
+		it1 = it2;
 	}
 
-	return false;
+	// Ray-casting algorithm
+	return (count % 2) ? true : false;
 }
 
 void Trigger::calculateDistance() {
@@ -117,4 +122,14 @@ void Trigger::prepare() {
 	_prepared = true;
 }
 
+/*
+ * Return true if a ray extending from (x, y) to (x, infinity)
+ * intersects the line segment from (x1, y1) to (x2, y2).
+ */
+bool Trigger::isRayIntersect(float x,  float y,
+                             float x1, float y1,
+                             float x2, float y2) const {
+	return true; // TODO
+}
+
 } // End of namespace Engines

src/engines/aurora/trigger.h

@@ -54,6 +54,10 @@ class Trigger : public Graphics::Renderable {
 private:
 	bool _prepared;
 	Common::BoundingBox _boundingbox;
+
+	bool isRayIntersect(float x,  float y,
+	                    float x1, float y1,
+	                    float x2, float y2) const;
 };
 
 } // End of namespace Engines