From 2a313fbc517d51cd6d1c2ab216e9531473354bf4 Mon Sep 17 00:00:00 2001
From: Amy Retzerau <amy.retzerau@gmail.com>
Date: Mon, 25 Aug 2025 11:32:01 +0200
Subject: [PATCH] feat: added FullscreenQuad

---
 FullScreenQuad.hpp | 33 +++++++++++++++++++++++++++++++++
 main.cpp           |  6 ++++++
 2 files changed, 39 insertions(+)
 create mode 100644 FullScreenQuad.hpp

diff --git a/FullScreenQuad.hpp b/FullScreenQuad.hpp
new file mode 100644
index 0000000..a56fc81
--- /dev/null
+++ b/FullScreenQuad.hpp
@@ -0,0 +1,33 @@
+#include <GL/glew.h>
+
+
+class FullScreenQuad {
+private:
+    unsigned int vao;
+public:
+    FullScreenQuad();
+    int getVAO() { return vao;}
+};
+
+FullScreenQuad::FullScreenQuad(){
+    float quadVertices[] = { // vertex attributes for a quad that fills the entire screen in Normalized Device Coordinates.
+        // positions   // texCoords
+        -1.0f,  1.0f,  0.0f, 1.0f,
+        -1.0f, -1.0f,  0.0f, 0.0f,
+         1.0f, -1.0f,  1.0f, 0.0f,
+
+        -1.0f,  1.0f,  0.0f, 1.0f,
+         1.0f, -1.0f,  1.0f, 0.0f,
+         1.0f,  1.0f,  1.0f, 1.0f
+    };
+    unsigned int vbo;
+    glGenVertexArrays(1, &vao);
+    glGenBuffers(1, &vbo);
+    glBindVertexArray(vao);
+    glBindBuffer(GL_ARRAY_BUFFER, vbo);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(quadVertices), &quadVertices, GL_STATIC_DRAW);
+    glEnableVertexAttribArray(0);
+    glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(float), (void*)0);
+    glEnableVertexAttribArray(1);
+    glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(float), (void*)(2 * sizeof(float)));
+}
diff --git a/main.cpp b/main.cpp
index 0e778d5..a96172e 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,6 +1,7 @@
 #include <GL/glew.h>
 #include <GLFW/glfw3.h>
 #include <cstdio>
+#include "FullScreenQuad.hpp"
 
 float vertices[] = {
     -0.5f, -0.5f, 0.0f,
@@ -129,6 +130,8 @@ int main(int argc, char** argv) {
     unsigned int shaderProgramm = compShader();
     unsigned int VAO = initVAO();
 
+    FullScreenQuad fsq{};
+
     while (!glfwWindowShouldClose(window))
     {
         processInput(window);
@@ -143,6 +146,9 @@ int main(int argc, char** argv) {
 
         glBindVertexArray(VAO);
 	glDrawArrays(GL_TRIANGLES, 0, 3);
+	glBindVertexArray(fsq.getVAO());	
+	glDrawArrays(GL_TRIANGLES, 0, 6);
+
         /* Poll for and process events */
         glfwPollEvents();