Fix Camera Projection and View Matrix Calculation

Headers/System/Camera.hpp

@@ -59,7 +59,7 @@ class Camera : public System::Component {
         return new_camera;
     }
 
-    void RenderStart() ; 
+    void RenderStart(int windowWidth, int windowHeight) ;
     void TakeScreenshot(const std::string& filename);
 }; 
 }

Headers/System/Scene.hpp

@@ -18,7 +18,7 @@ namespace System {
         /// Initializes the scene, setting up audio and physics engines.
         /// </summary>
         static void Initialize();
-        void Run();
+        void Run(int windowWidth, int windowHeight);
         static void Shutdown();
     };
 }

Sources/System/Camera.cpp

@@ -6,6 +6,7 @@
 #include <System/Graphics/GraphicsHelpers.h>
 #include <climits>
 #include <System/Image.hpp>
+#include <System/Transform.hpp>
 
 
 namespace System {
@@ -56,24 +57,38 @@ System::Camera::~Camera() {
     allCameras.erase(std::remove(allCameras.begin(), allCameras.end(), this), allCameras.end());
 }
 
-void System::Camera::RenderStart()  {
+void System::Camera::RenderStart(int windowWidth, int windowHeight) {
     if (targetTexture == nullptr) {
         // Render to the screen
         System::Graphics::GL::gl_glBindFramebuffer(System::Graphics::GL_FrameBufferTarget::GL_FRAMEBUFFER, 0);// render to the screen (This is done by using 0 as the second parameter of glBindFramebuffer).
-        System::Graphics::GL::gl_glViewport(viewport.x, viewport.y, viewport.width, viewport.height);
+
+        int pixelX = static_cast<int>(viewport.x * windowWidth);
+        int pixelY = static_cast<int>(viewport.y * windowHeight);
+        int pixelWidth = static_cast<int>(viewport.width * windowWidth);
+        int pixelHeight = static_cast<int>(viewport.height * windowHeight);
+
+        System::Graphics::GL::gl_glViewport(pixelX, pixelY, pixelWidth, pixelHeight);
         System::Graphics::GL::gl_glClear(System::Graphics::GL_BitField::COLOR_BUFFER_BIT | System::Graphics::GL_BitField::DEPTH_BUFFER_BIT);
+
+        float aspect = static_cast<float>(pixelWidth) / static_cast<float>(pixelHeight);
+
         projectionMatrix = orthographic
             ? System::Matrix4x4::Ortho(viewport.x, viewport.x + viewport.width, viewport.y, viewport.y + viewport.height, nearClipPlane, farClipPlane)
-            : System::Matrix4x4::Perspective(Mathf::Radians(60.0f), viewport.width / viewport.height, nearClipPlane, farClipPlane);
+            : System::Matrix4x4::Perspective(Mathf::Radians(60.0f), aspect, nearClipPlane, farClipPlane);
 
-        viewMatrix = Matrix4x4::LookAt(System::Vector3(0, 0, 5), System::Vector3(0, 0, 0), System::Vector3(0, 1, 0));
+        viewMatrix = Matrix4x4::LookAt(transform()->GetPosition(), transform()->GetPosition() + transform()->forward(), transform()->up());
 
     }else{
         //Render to the target texture
         System::Graphics::GL::gl_glBindFramebuffer(System::Graphics::GL_FrameBufferTarget::GL_FRAMEBUFFER, targetTexture->GetNativeTexturePtr());
         System::Graphics::GL::gl_glViewport(0, 0, targetTexture->GetWidth(), targetTexture->GetHeight());
         System::Graphics::GL::gl_glClear(System::Graphics::GL_BitField::COLOR_BUFFER_BIT | System::Graphics::GL_BitField::DEPTH_BUFFER_BIT);
 
+        float aspect = static_cast<float>(targetTexture->GetWidth()) / static_cast<float>(targetTexture->GetHeight());
+        projectionMatrix = orthographic
+            ? System::Matrix4x4::Ortho(viewport.x, viewport.x + viewport.width, viewport.y, viewport.y + viewport.height, nearClipPlane, farClipPlane)
+            : System::Matrix4x4::Perspective(Mathf::Radians(60.0f), aspect, nearClipPlane, farClipPlane);
+        viewMatrix = Matrix4x4::LookAt(transform()->GetPosition(), transform()->GetPosition() + transform()->forward(), transform()->up());
     }
 }
 void Camera::TakeScreenshot(const std::string& filename) {

Sources/System/Scene.cpp

@@ -60,7 +60,7 @@ physicsEngine = new JoltPhysicsEngine();
     }
 
 
-    void Scene::Run() {
+    void Scene::Run(int windowWidth, int windowHeight) {
         // Update All GameObjects
         for (GameObject* go : GameObject::allGameObjects) {
             for (auto const& [type, components] : go->components) {
@@ -71,7 +71,7 @@ physicsEngine = new JoltPhysicsEngine();
         }
         // Render Scene
         System::Camera* cam = Camera::Getmain();
-        cam->RenderStart();
+        cam->RenderStart(windowWidth, windowHeight);
         for (int i = 0; i < GameObject::allGameObjects.size(); i++) {
             GameObject* go = GameObject::allGameObjects[i];
             System::MeshRenderer* renderer = go->GetComponent<System::MeshRenderer>();

Tests/scene_render/scene_render.cpp

@@ -46,7 +46,7 @@ int main() {
     renderer->material = material;
 
     System::Scene scene;
-    scene.Run();
+    scene.Run(800, 600);
 
     delete material;
     delete shader;