feat(OpenGL-hello): rotate

OpenGL/hello/include/shader.h

@@ -106,7 +106,11 @@ public:
     { 
         glUniform4f(glGetUniformLocation(ID, name.c_str()), value1, value2, value3, value4); 
     }
-
+    // ------------------------------------------------------------------------
+    void setMat4(const std::string &name, float* value) const
+    { 
+        glUniformMatrix4fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE, value); 
+    }
 private:
     // utility function for checking shader compilation/linking errors.
     // ------------------------------------------------------------------------

OpenGL/hello/src/main.cpp

@@ -4,6 +4,9 @@
 #include <GLFW/glfw3.h>
 #include <cmath>
 #include <iostream>
+#include <glm/glm.hpp>
+#include <glm/gtc/matrix_transform.hpp>
+#include <glm/gtc/type_ptr.hpp>
 
 // 四边形顶点
 float vertices[] = {
@@ -24,7 +27,7 @@ void framebuffer_size_callback(GLFWwindow *window, int width, int height);
 void processInput(GLFWwindow *window);
 
 // settings
-const unsigned int SCR_WIDTH = 800;
+const unsigned int SCR_WIDTH = 600;
 const unsigned int SCR_HEIGHT = 600;
 
 int main() {
@@ -37,7 +40,7 @@ int main() {
   // glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
 
   // 创建窗口
-  GLFWwindow *window = glfwCreateWindow(800, 600, "LearnOpenGL", NULL, NULL);
+  GLFWwindow *window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", NULL, NULL);
   if (window == NULL) {
     std::cout << "Failed to create GLFW window" << std::endl;
     glfwTerminate();
@@ -144,6 +147,7 @@ int main() {
   // 绑定纹理
   shader.setInt("texture1", 0);
   shader.setInt("texture2", 1);
+  // 设置变换矩阵
 
   // 循环渲染
   while (!glfwWindowShouldClose(window)) {
@@ -162,6 +166,12 @@ int main() {
 
     // 绘制三角形
     shader.use();
+
+    glm::mat4 trans(1.0f);
+    trans = glm::translate(trans,glm::vec3(0.5,-0.5,0.0));
+    trans = glm::rotate(trans, (float)glfwGetTime(), glm::vec3(0.0, 0.5, 0.5));
+    trans = glm::scale(trans, glm::vec3(0.5, 0.5, 0.5));
+    shader.setMat4("trans",glm::value_ptr(trans));
     glBindVertexArray(VAO);
     glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
 

OpenGL/hello/src/tex.vs

@@ -6,9 +6,11 @@ layout (location = 2) in vec2 aTexCoord;
 out vec3 ourColor;
 out vec2 TexCoord;
 
+uniform mat4 trans;
+
 void main()
 {
-    gl_Position = vec4(aPos, 1.0);
+    gl_Position = trans * vec4(aPos, 1.0);
     ourColor = aColor;
     TexCoord = aTexCoord;
 }