source: opengl-game/game02.cpp@ 92bc4fe

// Include standard headers
#include <stdio.h>
#include <stdlib.h>

// Include GLEW
#include <GL/glew.h>

// Include GLFW
#include <GLFW/glfw3.h>
GLFWwindow* window;

// Include GLM
#include <glm/glm.hpp>
using namespace glm;

#include "common/shader.hpp"

int main( void )
{
        // Initialise GLFW
        if( !glfwInit() )
        {
                fprintf( stderr, "Failed to initialize GLFW\n" );
                getchar();
                return -1;
        }

        glfwWindowHint(GLFW_SAMPLES, 4);
        glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
        glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
        glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE); // To make MacOS happy; should not be needed
        glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);

        // Open a window and create its OpenGL context
        window = glfwCreateWindow( 1024, 768, "Tutorial 02 - Red triangle", NULL, NULL);
        if( window == NULL ){
                fprintf( stderr, "Failed to open GLFW window. If you have an Intel GPU, they are not 3.3 compatible. Try the 2.1 version of the tutorials.\n" );
                getchar();
                glfwTerminate();
                return -1;
        }
        glfwMakeContextCurrent(window);

        // Initialize GLEW
        glewExperimental = true; // Needed for core profile
        if (glewInit() != GLEW_OK) {
                fprintf(stderr, "Failed to initialize GLEW\n");
                getchar();
                glfwTerminate();
                return -1;
        }

        // Ensure we can capture the escape key being pressed below
        glfwSetInputMode(window, GLFW_STICKY_KEYS, GL_TRUE);

        // Dark blue background
        glClearColor(0.0f, 0.0f, 0.4f, 0.0f);

        GLuint VertexArrayID;
        glGenVertexArrays(1, &VertexArrayID);
        glBindVertexArray(VertexArrayID);

        // Create and compile our GLSL program from the shaders
        GLuint programID = LoadShaders("SimpleVertexShader.vertexshader", "SimpleFragmentShader.fragmentshader");


        static const GLfloat g_vertex_buffer_data[] = {
                -1.0f, -1.0f, 0.0f,
                 1.0f, -1.0f, 0.0f,
                 0.0f,  1.0f, 0.0f,
        };

        GLuint vertexbuffer;
        glGenBuffers(1, &vertexbuffer);
        glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
        glBufferData(GL_ARRAY_BUFFER, sizeof(g_vertex_buffer_data), g_vertex_buffer_data, GL_STATIC_DRAW);

        do{

                // Clear the screen
                glClear( GL_COLOR_BUFFER_BIT );

                // Use our shader
                glUseProgram(programID);

                // 1rst attribute buffer : vertices
                glEnableVertexAttribArray(0);
                glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
                glVertexAttribPointer(
                        0,                  // attribute 0. No particular reason for 0, but must match the layout in the shader.
                        3,                  // size
                        GL_FLOAT,           // type
                        GL_FALSE,           // normalized?
                        0,                  // stride
                        (void*)0            // array buffer offset
                );

                // Draw the triangle !
                glDrawArrays(GL_TRIANGLES, 0, 3); // 3 indices starting at 0 -> 1 triangle

                glDisableVertexAttribArray(0);

                // Swap buffers
                glfwSwapBuffers(window);
                glfwPollEvents();

        } // Check if the ESC key was pressed or the window was closed
        while( glfwGetKey(window, GLFW_KEY_ESCAPE ) != GLFW_PRESS &&
                   glfwWindowShouldClose(window) == 0 );

        // Cleanup VBO
        glDeleteBuffers(1, &vertexbuffer);
        glDeleteVertexArrays(1, &VertexArrayID);
        glDeleteProgram(programID);

        // Close OpenGL window and terminate GLFW
        glfwTerminate();

        return 0;
}