Added triangle function, not working perfectly but u see something like a triangle

.gitignore

@@ -7,6 +7,7 @@ build/
 /data/*
 !/data/README.txt
 /result*
+/cmake-build-debug
 
 # Latex stuff
 *.aux

ex1.cpp

@@ -40,8 +40,8 @@ int main() {
   // Set up the camera
   PerspectiveCamera camera;
   camera.setFovAngle(70);
-  camera.setPosition(Vector3d(-2.5f, 2.5f, -10.0f));
-  camera.setForwardDirection(Vector3d(0.25f, -0.33f, 1.0f));
+  camera.setPosition(Vector3d(-2.5f, 2.5f, -12.0f));
+  camera.setForwardDirection(Vector3d(0.0f, -0.33f, 1.0f));
   camera.setUpDirection(Vector3d(0.2f, 1.0f, 0.0f));
 
   // Render the scene

primitive/triangle.cpp

@@ -21,19 +21,63 @@ Triangle::Triangle(Vector3d const &a, Vector3d const &b, Vector3d const &c, Vect
 
 
 bool Triangle::intersect(Ray &ray) const {
-  // IMPLEMENT ME!
+    Vector3d edge1 = this->vertex[0] - this->vertex[2];
+    Vector3d edge2 = this->vertex[1] - this->vertex[2];
+    Vector3d normalVector = crossProduct(edge1, edge2);
+    float d = dotProduct(this->vertex[0], normalVector) / length(normalVector);
+
+    // catch divided by 0
+    float dotDirectionNormalVector = dotProduct(ray.direction, normalVector);
+    if (dotDirectionNormalVector == 0) {
+        return false;
+    }
+
+    float t = (d - dotProduct(ray.origin, ray.direction)) / dotDirectionNormalVector;
+    Vector3d p = ray.origin + t * ray.direction;
+
+    // Barycentric Coordinates a,b to determine if intersect with Triangle
+    float triangleArea = length(normalVector) / 2;
+
+    Vector3d rightSide = crossProduct(this->vertex[2] - this->vertex[1], p - this->vertex[1]);
+    Vector3d leftSide = crossProduct(this->vertex[0] - this->vertex[2], p - this->vertex[2]);
+
+    float triangleAreaRightSide = length(rightSide) / 2;
+    float triangleAreaLeftSide = length(leftSide) / 2;
+
+    float a = triangleAreaRightSide / triangleArea;
+
+    float b = triangleAreaLeftSide / triangleArea;
 
     // Determine whether the ray intersects the triangle
 
+
+    if(1.0f - a - b >= 1.0f || 0.0f >= a || 0.0f >= b){
+        return false;
+    }
+
+    if(dotProduct(normalVector, leftSide) < 0){
+        return false;
+    }
+
+    if(dotProduct(normalVector, rightSide) < 0){
+        return false;
+    }
+
     // Test whether this is the foremost primitive in front of the camera
+    if (t >= ray.length) {
+        //it is bigger so further away
+        return false;
+    }
 
     // (Optional for now) Calculate the normal
 
     // (Optional for now) Calculate the surface position
 
     // Set the new length and the current primitive
+    ray.length = t;
+    ray.primitive = this;
 
-  return false;
+    return true;
 }
 
 // Bounding box ////////////////////////////////////////////////////////////////