#include <GL/glut.h>

#define WIDTH 640
#define HEIGHT 480

unsigned int TEX_NAME;

unsigned char* tex_data;

void display();

int main(int argc, char** argv)
{
    glutInit(&argc, argv);

    glutInitWindowSize(WIDTH, HEIGHT);
    glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE);

    glutCreateWindow("A test thing");

    // Set all callback functions
    glutDisplayFunc(display);

    // Set up opengl
    glViewport(0, 0, WIDTH, HEIGHT);
    glEnable(GL_TEXTURE_2D);
    glClearColor(0.0f, 0.5f, 0.5f, 0.0f);

    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(0.0, 1.0, 0.0, 1.0, -1.0, 1.0);

    // Prepare texture-related nonsense
    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

    tex_data = new unsigned char[WIDTH * HEIGHT * 4];

    for (int i = 0; i < WIDTH * HEIGHT * 4; i++) {
        tex_data[i] = 0;
    }

    glGenTextures(1, &TEX_NAME);
    glBindTexture(GL_TEXTURE_2D, TEX_NAME);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, WIDTH, HEIGHT, 0, GL_RGBA, GL_UNSIGNED_BYTE, tex_data);

    glutMainLoop();

    return 0;
}

void display()
{
    glClear(GL_COLOR_BUFFER_BIT);
    glEnable(GL_TEXTURE_2D);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();

    glBindTexture(GL_TEXTURE_2D, TEX_NAME);

    // Draw quad
    glBegin(GL_QUADS);
    glColor3f(1.0f, 1.0f, 1.0f);
    glTexCoord2f(0.0f, 0.0f);
    glVertex3f(0.0, 0.0, 0.0);
    glTexCoord2f(1.0f, 0.0f);
    glVertex3f(1.0, 0.0, 0.0);
    glTexCoord2f(1.0f, 1.0f);
    glVertex3f(1.0, 1.0, 0.0);
    glTexCoord2f(0.0f, 1.0f);
    glVertex3f(0.0, 1.0, 0.0);
    glEnd();

    glutSwapBuffers();
}