Added basic triangle raycasting.

src/dawn/physics/3d/Ray3D.cpp

@@ -23,6 +23,9 @@ bool_t Dawn::raytestSphere(
   glm::vec3 *hit,
   glm::vec3 *normal
 ) {
+  assertNotNull(hit);
+  assertNotNull(normal);
+
   glm::vec3 h, n;
   auto result = glm::intersectRaySphere(
     ray.origin, ray.direction,
@@ -30,8 +33,8 @@ bool_t Dawn::raytestSphere(
     h, n
   );
 
-  if(hit != nullptr) *hit = h;
-  if(normal != nullptr) *normal = n;
+  *hit = h;
+  *normal = n;
 
   return result;
 }
@@ -39,19 +42,54 @@ bool_t Dawn::raytestSphere(
 bool_t Dawn::raytestTriangle(
   struct Ray3D ray,
   struct PhysicsTriangle triangle,
-  glm::vec2 *hit,
-  float_t *distance
+  glm::vec3 *hitPoint,
+  glm::vec3 *hitNormal,
+  float_t *hitDistance
 ) {
-  glm::vec2 h;
-  float_t d;
-  auto result = glm::intersectRayTriangle(
-    ray.origin, ray.direction,
-    triangle.v0, triangle.v1, triangle.v2,
-    h, d
-  );
-  if(hit != nullptr) *hit = h;
-  if(distance != nullptr) *distance = d;
-  return result;
+  assertNotNull(hitPoint);
+  assertNotNull(hitNormal);
+  assertNotNull(hitDistance);
+
+  // Calculate the normal of the triangle
+  glm::vec3 e0 = triangle.v1 - triangle.v0;
+  glm::vec3 e1 = triangle.v2 - triangle.v0;
+  glm::vec3 normal = glm::normalize(glm::cross(e0, e1));
+
+  // Calculate the denominator of the ray-triangle intersection formula
+  float_t denominator = glm::dot(normal, ray.direction);
+
+  // If the denominator is zero, the ray and triangle are parallel and there is no intersection
+  if(denominator == 0) return -1;
+
+  // Calculate the distance from the ray origin to the plane of the triangle
+  float_t d = glm::dot(triangle.v0 - ray.origin, normal) / denominator;
+
+  // If the distance is negative, the intersection point is behind the ray origin and there is no intersection
+  if(d < 0) return -1;
+
+  // Calculate the intersection point
+  glm::vec3 intersectionPoint = ray.origin + d * ray.direction;
+
+  // Check if the intersection point is inside the triangle
+  glm::vec3 edge0 = triangle.v1 - triangle.v0;
+  glm::vec3 edge1 = triangle.v2 - triangle.v1;
+  glm::vec3 edge2 = triangle.v0 - triangle.v2;
+  glm::vec3 c0 = intersectionPoint - triangle.v0;
+  glm::vec3 c1 = intersectionPoint - triangle.v1;
+  glm::vec3 c2 = intersectionPoint - triangle.v2;
+  glm::vec3 n0 = glm::cross(edge0, c0);
+  glm::vec3 n1 = glm::cross(edge1, c1);
+  glm::vec3 n2 = glm::cross(edge2, c2);
+  if (glm::dot(n0, normal) >= 0 && glm::dot(n1, normal) >= 0 && glm::dot(n2, normal) >= 0) {
+    // If the intersection point is inside the triangle, set the hit point, normal and distance
+    *hitPoint = intersectionPoint;
+    *hitNormal = normal;
+    *hitDistance = d;
+    return true;
+  }
+
+  // If the intersection point is outside the triangle, there is no intersection
+  return false;
 }
 
 bool_t Dawn::raytestAABB(

src/dawn/physics/3d/Ray3D.hpp

@@ -26,8 +26,9 @@ namespace Dawn {
   bool_t raytestTriangle(
     struct Ray3D ray,
     struct PhysicsTriangle triangle,
-    glm::vec2 *hit,
-    float_t *distance
+    glm::vec3 *hitPoint,
+    glm::vec3 *hitNormal,
+    float_t *hitDistance
   );
 
   bool_t raytestAABB(