assessment3.1.cpp

/* OpenGL module
 * Assessment 5
 *
 * author: Miguel Gonzalez <[email protected]>
 */

#include <GL/glut.h>

int number = 12;

GLubyte wb[2]={0x00, 0xFF};
GLubyte check[1024];

void init()
{
  for (int i=0;i<(number*number);i++)
  {
    for (int j=0; j<number; j++)
    {
      check[i*number+j] = wb[(i/number+j)%2];
    }
  }
}

void drawCheckerboard()
{
  glRasterPos3f(0.0f, 0.0f, 0.0f);
  glColor3f(1.0f, 0.0f, 0.0f);
  glBitmap(number*number, number*number, 0.0, 0.0, 0.0, 0.0, check);
  glRasterPos3f(0.0f, 0.0f, 0.0f);
  glColor3f(0.0f, 1.0f, 0.0f);
  glEnable(GL_COLOR_LOGIC_OP);
  glLogicOp(GL_XOR);
  glBitmap(number*number, number*number, -4.0, 4.0, 0.0, 0.0, check);
  glDisable(GL_COLOR_LOGIC_OP);
  glRasterPos3f(-1.0f, 1.0f, 0.0f);
  glCopyPixels(0.0f, 0.0f, 128.0f, 128.0f, GL_COLOR);
}

void display()
{
  glMatrixMode(GL_MODELVIEW);
  glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
  glClear(GL_COLOR_BUFFER_BIT);
  glLoadIdentity();

  glPushMatrix();
  drawCheckerboard();
  glPopMatrix();
  glFlush();
  glutSwapBuffers();
}

void reshape(GLsizei w, GLsizei h)
{
  glViewport (0, 0, (GLsizei) w, (GLsizei) h);
  glLoadIdentity();
}

int main(int argc, char** argv)
{
  glutInit(&argc, argv);
  init();
  glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
  glutInitWindowSize(800, 600);
  glutInitWindowPosition(100, 100);
  glutCreateWindow("OpenGL - Assessment 4");

  glDisable(GL_LIGHTING);
  glEnable(GL_COLOR_LOGIC_OP);

  glutReshapeFunc(reshape);
  glutDisplayFunc(display);

  glutMainLoop();
  return 0;
}