Dumb

src/main.cpp

@@ -1,10 +1,27 @@
 #include <glad/glad.h>
 #include <GLFW/glfw3.h>
 #include <stdio.h>
+#include <vector>
+
+#include "shaders.cpp"
 
 #define WINDOW_WIDTH 640
 #define WINDOW_HEIGHT 480
 
+const char *vertexShaderSource = "#version 330 core\n"
+	"layout (location = 0) in vec3 aPos;\n"
+	"void main()\n"
+	"{\n"
+	"   gl_Position = vec4(aPos.x, aPos.y, aPos.z, 1.0);\n"
+	"}\0";
+
+const char *fragShaderSource = "#version 330 core\n"
+"out vec4 FragColor;\n"
+"void main()\n"
+"{\n"
+"	FragColor = vec4(1.0f, 0.5f, 0.2f, 1.0f);\n"
+"}\0";
+
 static float verts[] = {
 	-0.5f, -0.5f, 0.0f,
 	 0.5f, -0.5f, 0.0f,
@@ -22,16 +39,41 @@ void processInput(GLFWwindow *win) {
 	}
 }
 
-void renderCallback(GLFWwindow *win) {
+void preRenderCallback(GLFWwindow *win) {
-	glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
-	glClear(GL_COLOR_BUFFER_BIT);
-
 	unsigned int VBO;
 	glGenBuffers(1, &VBO);
 
 	glBindBuffer(GL_ARRAY_BUFFER, VBO);
 	glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_DYNAMIC_DRAW); // for moving stuff
 	//glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_STATIC_DRAW);
+
+	// Compile a bunch of shaders etc
+	unsigned int vertShader = Shader::compile(GL_VERTEX_SHADER, vertexShaderSource);
+	unsigned int fragShader = Shader::compile(GL_FRAGMENT_SHADER, fragShaderSource);
+	unsigned int shaders[2] = {vertShader, fragShader};
+
+	// Create a shader program & link the shaders etc
+	unsigned int shaderProg;
+	shaderProg = Shader::createProgram( std::vector<unsigned int> (std::begin(shaders), std::end(shaders)) );
+
+	// Copy verts into buffer
+	glBindBuffer(GL_ARRAY_BUFFER, VBO);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_STATIC_DRAW);
+
+	// Set attrib pointers
+	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
+	glEnableVertexAttribArray(0);
+
+	// Use the shader program whenever we want to render
+	glUseProgram(shaderProg);
+	glDeleteShader(vertShader);
+	glDeleteShader(vertShader);  
+
+}
+
+void renderCallback(GLFWwindow *win) {
+	glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
+	glClear(GL_COLOR_BUFFER_BIT);
 }
 
 int main() {
@@ -57,6 +99,8 @@ int main() {
 	glViewport(0, 0, WINDOW_WIDTH, WINDOW_HEIGHT);
 	glfwSetFramebufferSizeCallback(win, framebuffer_size_callback);
 
+	preRenderCallback(win);
+
 	while (!glfwWindowShouldClose(win)) {
 		// Handle input
 		processInput(win);

src/shader_loader.cpp

@@ -1,2 +0,0 @@
-#include <fstream>
-

src/shaders.cpp

@@ -0,0 +1,48 @@
+#include <fstream>
+#include <glad/glad.h>
+#include <vector>
+
+namespace Shader {
+	unsigned int compile(GLenum shadertype, const char* shaderSource) {
+		unsigned int shader;
+		shader = glCreateShader(shadertype);
+		glShaderSource(shader, 1, &shaderSource, NULL);
+		glCompileShader(shader);
+
+		int success;
+		char infolog[512];
+		glGetShaderiv(shader, GL_COMPILE_STATUS, &success);
+		if (!success) {
+			glGetShaderInfoLog(shader, 512, NULL, infolog);
+			printf("Shader Compilation Error:\n%s\n", infolog);
+		} else {
+			printf("Compiled shader %u!\n", shadertype);
+		}
+
+		return shader;
+	}
+
+	unsigned int createProgram(std::vector<unsigned int> shaders) {
+		unsigned int shaderProg;
+		shaderProg = glCreateProgram();
+
+		// Link the shaders
+		for(unsigned int s : shaders) 
+			glAttachShader(shaderProg, s);
+
+		glLinkProgram(shaderProg);
+
+		// Check for errors
+		int success;
+		char infolog[512];
+		glGetProgramiv(shaderProg, GL_LINK_STATUS, &success);
+		if (!success) {
+			glGetProgramInfoLog(shaderProg, 512, NULL, infolog);
+			printf("Shader Program Linking Error:\n%s\n", infolog);
+		} else {
+			printf("Linked shaders & created program: %u\n", shaderProg);
+		}
+
+		return shaderProg;
+	}
+}