[CORE][FIX] Hit test fix

- Add critical debug logs
- Change transforming ray to local space to transforming vex to world space (because of scaling)
- Fix not updating bounding box causing hit test failure

FinalProject/FinalProject.vcxproj

@@ -120,7 +120,6 @@
     <ClCompile Include="modelthumbnailwidget.cpp" />
     <ClCompile Include="pagewidget.cpp" />
     <ClCompile Include="pushbutton.cpp" />
-    <ClCompile Include="ray.cpp" />
     <ClCompile Include="renderable.cpp" />
     <ClCompile Include="roundedcornerwidget.cpp" />
     <ClCompile Include="sceneviewer.cpp" />

FinalProject/FinalProject.vcxproj.filters

@@ -171,9 +171,6 @@
     <ClCompile Include="skybox.cpp">
       <Filter>Source Files\OpenGL Abstractions</Filter>
     </ClCompile>
-    <ClCompile Include="ray.cpp">
-      <Filter>Source Files\OpenGL Abstractions</Filter>
-    </ClCompile>
     <ClCompile Include="boundary.cpp">
       <Filter>Source Files\OpenGL Abstractions</Filter>
     </ClCompile>

FinalProject/mesh.cpp

@@ -54,7 +54,7 @@ void Mesh::setupMesh() {
     //_vao.setVertexAttributePointer(4, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), (void*)OFFSETOF(Vertex, _bitangent));
 }
 
-HitRecord Mesh::hit(const Ray& ray) const {
+HitRecord Mesh::hit(const Ray& ray, const glm::mat4& modelMatrix) const {
     // Test whether the ray hits the mesh
     
     // Traverse the indices to test every triangle
@@ -64,20 +64,30 @@ HitRecord Mesh::hit(const Ray& ray) const {
         Vertex v1 = _vertices[_indices[i + 1]];
         Vertex v2 = _vertices[_indices[i + 2]];
 
+        glm::vec3 v0pos = glm::vec3(modelMatrix * glm::vec4(v0._position, 1.0f));
+        glm::vec3 v1pos = glm::vec3(modelMatrix * glm::vec4(v1._position, 1.0f));
+        glm::vec3 v2pos = glm::vec3(modelMatrix * glm::vec4(v2._position, 1.0f));
+
         // Moller Trumbore algorithm
         // https://en.wikipedia.org/wiki/M%C3%B6ller%E2%80%93Trumbore_intersection_algorithm
-        glm::vec3 edge1 = v1._position - v0._position;
-        glm::vec3 edge2 = v2._position - v0._position;
+        glm::vec3 edge1 = v1pos - v0pos;
+        glm::vec3 edge2 = v2pos - v0pos;
         glm::vec3 pvec = glm::cross(ray.direction(), edge2);
         float det = glm::dot(edge1, pvec);
-        if (det < 0.0001f) continue;
+        if (abs(det) < 0.0001f) {
+            continue;
+        }
         float invDet = 1.0f / det;
-        glm::vec3 tvec = ray.origin() - v0._position;
+        glm::vec3 tvec = ray.origin() - v0pos;
         float u = glm::dot(tvec, pvec) * invDet;
-        if (u < 0.0f || u > 1.0f) continue;
+        if (u < 0.0f || u > 1.0f) {
+            continue;
+        }
         glm::vec3 qvec = glm::cross(tvec, edge1);
         float v = glm::dot(ray.direction(), qvec) * invDet;
-        if (v < 0.0f || u + v > 1.0f) continue;
+        if (v < 0.0f || u + v > 1.0f) {
+            continue;
+        }
         float t = glm::dot(edge2, qvec) * invDet;
         if (t > 0.0001f) {
             // Hit

FinalProject/mesh.h

@@ -36,7 +36,7 @@ public:
 
 public:
     void render(const ShaderProgram& shader) const ;
-    HitRecord hit(const Ray& ray) const;
+    HitRecord hit(const Ray& ray, const glm::mat4& modelMatrix) const;
 
 private:
     void setupMesh();

FinalProject/model.cpp

@@ -189,22 +189,14 @@ void Model::render(const ShaderProgram& shader) const {
     }
 }
 
-HitRecord Model::hit(const Ray& ray) const {
-    // 1. use the aabb method to test whether hit the boundary box
-    // 2. if hit, use the mesh hit method to test whether hit the mesh
-    
-    if (_boundBox.hit(ray)) {
-        for (unsigned int i = 0; i < _meshes.size(); i++) {
-            HitRecord hitRecord = _meshes[i].hit(ray);
-            if (hitRecord.hitted()) {
-                return hitRecord;
-            }
+HitRecord Model::hit(const Ray& ray, const glm::mat4& modelMatrix) const {
+    for (unsigned int i = 0; i < _meshes.size(); i++) {
+        HitRecord hitRecord = _meshes[i].hit(ray, modelMatrix);
+        if (hitRecord.hitted()) {
+            return hitRecord;
         }
-        return HitRecord();
-    }
-    else {
-        return HitRecord(); // return a false hit record
     }
+    return HitRecord();
 }
 
 Model* Model::copyToCurrentContext() const {

FinalProject/model.h

@@ -49,5 +49,5 @@ private:
 
 public:
     void render(const ShaderProgram& shader) const;
-    HitRecord hit(const Ray& ray) const;    // test the hit record of an input array (transformed into local space)
+    HitRecord hit(const Ray& ray, const glm::mat4& modelMatrix) const;    // test the hit record of an input array (transformed into local space)
 };

FinalProject/ray.cpp

@@ -1,14 +0,0 @@
-#include "ray.h"
-
-Ray Ray::toLocalSpace(glm::mat4 modelMatrix) const {
-    // The model matrix is the matrix that transforms local space to world space
-    // Therefore the inverse of the model matrix transforms world space to local space
-    glm::mat4 inversedModelMatrix = glm::inverse(modelMatrix);
-    
-    // Transform the origin and direction of the ray to local space
-    glm::vec4 localOrigin = inversedModelMatrix * glm::vec4(_origin, 1.0f);
-    glm::vec4 localDirection = inversedModelMatrix * glm::vec4(_direction, 0.0f);
-    
-    // Return the new ray
-    return Ray(glm::vec3(localOrigin), glm::vec3(localDirection));
-}

FinalProject/ray.h

@@ -14,7 +14,4 @@ public:
 public:
     inline glm::vec3 origin() const { return _origin; }
     inline glm::vec3 direction() const { return _direction; }
-
-public:
-    Ray toLocalSpace(glm::mat4 modelMatrix) const;
 };

FinalProject/renderable.cpp

@@ -75,12 +75,17 @@ void Renderable::render(ShaderProgram shader) {
 void Renderable::updateBoundary() {
     // Traverse every vertex in the transferred model and update the boundary
     Boundary newBoundary;
+    glm::mat4 model = modelMatrix();
     for (auto& mesh : _model->meshes()) {
         for (auto& vertex : mesh.vertices()) {
-            glm::vec4 transformedVertex = modelMatrix() * glm::vec4(vertex._position, 1.0f);
+            glm::vec4 transformedVertex = model * glm::vec4(vertex._position, 1.0f);
             newBoundary.updateControlPoints(glm::vec3(transformedVertex));
         }
     }
+    _boundary = newBoundary;
+    Logger::debug("Boundary updated");
+    Logger::debug("[+] Bottom control point: " + std::to_string(newBoundary.bottomControlPoint().x) + ", " + std::to_string(newBoundary.bottomControlPoint().y) + ", " + std::to_string(newBoundary.bottomControlPoint().z));
+    Logger::debug("[+] Top control point: " + std::to_string(newBoundary.topControlPoint().x) + ", " + std::to_string(newBoundary.topControlPoint().y) + ", " + std::to_string(newBoundary.topControlPoint().z));
 }
 
 HitRecord Renderable::hit(const Ray& ray) const {
@@ -90,6 +95,6 @@ HitRecord Renderable::hit(const Ray& ray) const {
     }
     else {
         // If the ray hits the boundary box
-        return _model->hit(ray.toLocalSpace(modelMatrix()));
+        return _model->hit(ray, modelMatrix());
     }
 }

FinalProject/sceneviewer.cpp

@@ -125,6 +125,7 @@ void SceneViewer::initializeGL() {
     Model* model = new Model("E:\\Repositories\\CollegeProjects\\CGAssignments\\FinalProject\\Models\\backpack\\backpack.obj");
     Renderable* backpack = new Renderable(model);
     backpack->move(glm::vec3(-5.0f, -2.0f, -2.0f));
+    backpack->updateBoundary();
     _objects.push_back(backpack);
     
     Renderable* backpack2 = new Renderable(model);