/*
When creating your project, uncheck OWL,
uncheck Class Library, select Static
instead of Dynamic and change the target
model to Console from GUI.
Also link glut.lib to your project once its done.
*/

#include <windows.h>   // Standard Header For Most Programs
#include <gl/gl.h>     // The GL Header File
#include <gl/glut.h>   // The GL Utility Toolkit (Glut) Header

void init ( GLvoid )     // Create Some Everyday Functions
{

  glShadeModel(GL_SMOOTH);							// Enable Smooth Shading
	glClearColor(0.0f, 0.0f, 0.0f, 0.5f);				// Black Background
	glClearDepth(1.0f);									// Depth Buffer Setup
	glEnable(GL_DEPTH_TEST);							// Enables Depth Testing
	glDepthFunc(GL_LEQUAL);								// The Type Of Depth Testing To Do
   glEnable ( GL_COLOR_MATERIAL );
	glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
}

void display ( void )   // Create The Display Function
{
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);	// Clear Screen And Depth Buffer
	glLoadIdentity();									// Reset The Current Modelview Matrix
	glTranslatef(-1.5f,0.0f,-6.0f);						// Move Left 1.5 Units And Into The Screen 6.0
	glBegin(GL_TRIANGLES);								// Drawing Using Triangles
		glVertex3f( 0.0f, 1.0f, 0.0f);					// Top
		glVertex3f(-1.0f,-1.0f, 0.0f);					// Bottom Left
		glVertex3f( 1.0f,-1.0f, 0.0f);					// Bottom Right
	glEnd();											// Finished Drawing The Triangle
	glTranslatef(3.0f,0.0f,0.0f);						// Move Right 3 Units
	glBegin(GL_QUADS);									// Draw A Quad
		glVertex3f(-1.0f, 1.0f, 0.0f);					// Top Left
		glVertex3f( 1.0f, 1.0f, 0.0f);					// Top Right
		glVertex3f( 1.0f,-1.0f, 0.0f);					// Bottom Right
		glVertex3f(-1.0f,-1.0f, 0.0f);					// Bottom Left
	glEnd();


  glutSwapBuffers ( );
  // Swap The Buffers To Not Be Left With A Clear Screen
}

void reshape ( int w, int h )   // Create The Reshape Function (the viewport)
{
  glViewport     ( 0, 0, w, h );
  glMatrixMode   ( GL_PROJECTION );  // Select The Projection Matrix
  glLoadIdentity ( );                // Reset The Projection Matrix
  if ( h==0 )  // Calculate The Aspect Ratio Of The Window
     gluPerspective ( 80, ( float ) w, 1.0, 5000.0 );
  else
     gluPerspective ( 80, ( float ) w / ( float ) h, 1.0, 5000.0 );
  glMatrixMode   ( GL_MODELVIEW );  // Select The Model View Matrix
  glLoadIdentity ( );    // Reset The Model View Matrix
}

void keyboard ( unsigned char key, int x, int y )  // Create Keyboard Function
{
  switch ( key ) {
    case 27:        // When Escape Is Pressed...
      exit ( 0 );   // Exit The Program
      break;        // Ready For Next Case
    default:        // Now Wrap It Up
      break;
  }
}

void arrow_keys ( int a_keys, int x, int y )  // Create Special Function (required for arrow keys)
{
  switch ( a_keys ) {
    case GLUT_KEY_UP:     // When Up Arrow Is Pressed...
      glutFullScreen ( ); // Go Into Full Screen Mode
      break;
    case GLUT_KEY_DOWN:               // When Down Arrow Is Pressed...
      glutReshapeWindow ( 500, 500 ); // Go Into A 500 By 500 Window
      break;
    default:
      break;
  }
}

void main ( int argc, char** argv )   // Create Main Function For Bringing It All Together
{
  glutInit            ( &argc, argv ); // Erm Just Write It =)
  init ();
  glutInitDisplayMode ( GLUT_RGB | GLUT_DOUBLE ); // Display Mode
  glutInitWindowSize  ( 500, 500 ); // If glutFullScreen wasn't called this is the window size
  glutCreateWindow    ( "NeHe's OpenGL Framework" ); // Window Title (argv[0] for current directory as title)
  glutFullScreen      ( );          // Put Into Full Screen
  glutDisplayFunc     ( display );  // Matching Earlier Functions To Their Counterparts
  glutReshapeFunc     ( reshape );
  glutKeyboardFunc    ( keyboard );
  glutSpecialFunc     ( arrow_keys );
  glutMainLoop        ( );          // Initialize The Main Loop
}