From d7efcff2c8a31bbbb2764702d639ff7739a001b4 Mon Sep 17 00:00:00 2001
From: miaurizius <maurice@miaurizius.de>
Date: Fri, 24 Apr 2026 13:23:15 +0200
Subject: [PATCH] added camera movement

---
 CMakeLists.txt     |  3 ++-
 include/Camera.hpp | 31 +++++++++++++++++++++++
 src/main.cpp       | 63 ++++++++++++++++++++++++++++++++++++----------
 3 files changed, 83 insertions(+), 14 deletions(-)
 create mode 100644 include/Camera.hpp

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 02a17ac..54f33a7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -13,7 +13,8 @@ add_executable(${PROJECT_NAME} src/main.cpp
         src/Shader.cpp
         include/Shader.hpp
         include/IndexBuffer.hpp
-        libs/stb_image.hpp)
+        libs/stb_image.hpp
+        include/Camera.hpp)
 
 target_compile_definitions(${PROJECT_NAME} PRIVATE $<$<CONFIG:Debug>:_DEBUG>)
 
diff --git a/include/Camera.hpp b/include/Camera.hpp
new file mode 100644
index 0000000..d7ca7a4
--- /dev/null
+++ b/include/Camera.hpp
@@ -0,0 +1,31 @@
+#pragma once
+
+#include "glm/glm.hpp"
+#include "glm/ext/matrix_transform.hpp"
+#include "glm/gtc/matrix_transform.hpp"
+
+class Camera {
+private:
+    glm::mat4 projection;
+    glm::mat4 view;
+    glm::mat4 viewProj;
+
+public:
+    Camera(float fov, float width, float height) {
+        projection = glm::perspective(fov/2.0f, width/height, 0.1f, 1000.f);
+        view = glm::mat4(1.0f);
+        update();
+    }
+
+    glm::mat4 getViewProj() {
+        return viewProj;
+    }
+
+    void update() {
+        viewProj = projection * view;
+    }
+
+    void translate(glm::vec3 v) {
+        view = glm::translate(view, v*-1.0f);
+    }
+};
\ No newline at end of file
diff --git a/src/main.cpp b/src/main.cpp
index 553a4ad..8002fbf 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -9,6 +9,7 @@
 #include "VertexBuffer.hpp"
 #include "Shader.hpp"
 #define STB_IMAGE_IMPLEMENTATION
+#include "Camera.hpp"
 #include "stb_image.hpp"
 #include "glm/glm.hpp"
 #include "glm/ext/matrix_transform.hpp"
@@ -80,7 +81,7 @@ int main() {
     #ifdef _DEBUG
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_DEBUG_FLAG); //remove for stable release
     #endif
-
+    SDL_GL_SetSwapInterval(1);
 
     uint32 flags = SDL_WINDOW_OPENGL; //| SDL_WINDOW_FULLSCREEN;
 
@@ -169,12 +170,11 @@ int main() {
     auto model = glm::mat4(1.0f);
     model = glm::scale(model, glm::vec3(1.2f));
 
-    auto projection = glm::ortho(-2.0f, 2.0f, -2.0f, 2.0f, -10.0f, 100.0f);
-    projection = glm::perspective(glm::radians(45.0f), 4.0f/3.0f, 0.1f, 100.0f);
+    Camera camera(90.0f, 800.0f, 600.0f);
+    camera.translate(glm::vec3(0.0f, 0.0f, 5.0f));
+    camera.update();
 
-    auto view = glm::translate(glm::mat4(1.0f), glm::vec3(0.0f, 0.0f, -3.0f));
-
-    auto modelViewProj = projection * view * model;
+    auto modelViewProj = camera.getViewProj() * model;
 
     int modelViewProjMatrixLocation = glGetUniformLocation(shader.getShaderId(), "u_modelViewProj");
 
@@ -185,13 +185,56 @@ int main() {
 
     bool running = true;
     SDL_Event e;
+
+    bool btnW;
+    bool btnS;
+    bool btnA;
+    bool btnD;
+
     while (running) {
+        while (SDL_PollEvent(&e)) {
+            if (e.type == SDL_EVENT_QUIT) {
+                running = false;
+            } else if (e.type == SDL_EVENT_KEY_DOWN) {
+                switch (e.key.key) {
+                    case SDLK_W: btnW = true; break;
+                    case SDLK_S: btnS = true; break;
+                    case SDLK_A: btnA = true; break;
+                    case SDLK_D: btnD = true; break;
+                    default: break;
+                }
+            } else if (e.type == SDL_EVENT_KEY_UP) {
+                switch (e.key.key) {
+                    case SDLK_W: btnW = false; break;
+                    case SDLK_S: btnS = false; break;
+                    case SDLK_A: btnA = false; break;
+                    case SDLK_D: btnD = false; break;
+                    default: break;
+                }
+            }
+        }
+
         glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
         glClear(GL_COLOR_BUFFER_BIT);
         time += delta;
 
+        if (btnW) {
+            camera.translate(glm::vec3(0.0f, 0.0f, -2.0f*delta));
+        }
+        if (btnS) {
+            camera.translate(glm::vec3(0.0f, 0.0f, 2.0f*delta));
+        }
+        if (btnA) {
+            camera.translate(glm::vec3(-1.0f*delta, 0.0f, 0.0f));
+        }
+        if (btnD) {
+            camera.translate(glm::vec3(1.0f*delta, 0.0f, 0.0f));
+        }
+
+        camera.update();
+
         model = glm::rotate(model, 1.0f*delta, glm::vec3(0.0f, 1.0f, 0.0f));
-        modelViewProj = projection * view * model;
+        modelViewProj = camera.getViewProj() * model;
 
         if (colorUniformLocation != 1) {
             glUniform4f(colorUniformLocation, sinf(time)*sinf(time), 0.0f, 1.0f, 1.0f);
@@ -209,12 +252,6 @@ int main() {
 
         SDL_GL_SwapWindow(window);
 
-        while (SDL_PollEvent(&e)) {
-            if (e.type == SDL_EVENT_QUIT) {
-                running = false;
-            }
-        }
-
         const uint64 endCounter = SDL_GetPerformanceCounter();
         const uint64 counterElapsed = endCounter - lastCounter;
         delta = (static_cast<float32>(counterElapsed) / static_cast<float32>(perfCounterFrequency));