varray.cpp

OPENGL2.0用于ARM11 3D处理

/*
 * License Applicability. Except to the extent portions of this file are
 * made subject to an alternative license as permitted in the SGI Free
 * Software License B, Version 1.1 (the "License"), the contents of this
 * file are subject only to the provisions of the License. You may not use
 * this file except in compliance with the License. You may obtain a copy
 * of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
 * Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
 * 
 * http://oss.sgi.com/projects/FreeB
 * 
 * Note that, as provided in the License, the Software is distributed on an
 * "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
 * DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
 * CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
 * PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
 * 
 * Original Code. The Original Code is: OpenGL Sample Implementation,
 * Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
 * Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
 * Copyright in any portions created by third parties is as indicated
 * elsewhere herein. All Rights Reserved.
 * 
 * Additional Notice Provisions: The application programming interfaces
 * established by SGI in conjunction with the Original Code are The
 * OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
 * April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
 * 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
 * Window System(R) (Version 1.3), released October 19, 1998. This software
 * was created using the OpenGL(R) version 1.2.1 Sample Implementation
 * published by SGI, but has not been independently verified as being
 * compliant with the OpenGL(R) version 1.2.1 Specification.
 *
 */

/*
 *  varray.c
 *  This program demonstrates vertex arrays.
 */
#include "stdafx.h"
#include <stdlib.h>
#include <stdio.h>

#include <gles/gles.h>
#include <math.h>


#define POINTER 1
#define INTERLEAVED 2

#define DRAWARRAY 1
#define ARRAYELEMENT  2
#define DRAWELEMENTS 3

int setupMethod = POINTER;
int derefMethod = DRAWARRAY;

static void display(void);
static void reshape(int w,int h);
static void init(void);
static void mouse();

void setupPointers(void)
{
   static GLshort vertices[] = {25, 25,
                       100, 325,
                       175, 25,
                       175, 325,
                       250, 25,
                       325, 325};
   static GLfloat colors[] = {1.0, 0.2, 0.2, 1.0,
                       0.2, 0.2, 1.0, 1.0,
                       0.8, 1.0, 0.2, 1.0,
                       0.75, 0.75, 0.75, 1.0,
                       0.35, 0.35, 0.35, 1.0,
                       0.5, 0.5, 0.5, 1.0};

   glEnableClientState (GL_VERTEX_ARRAY);
   glEnableClientState (GL_COLOR_ARRAY);

   glVertexPointer (2, GL_SHORT, 0, vertices);
   glColorPointer (4, GL_FLOAT, 0, colors);
}


static void init(void) 
{
   glClearColor (0.0, 0.0, 0.0, 0.0);
   glShadeModel (GL_SMOOTH);
   setupPointers ();
}

void VarrayRender()
{
   
   glClear (GL_COLOR_BUFFER_BIT);

   if (derefMethod == DRAWARRAY) 
      glDrawArrays (GL_TRIANGLES, 0, 6);
 /*  else if (derefMethod == ARRAYELEMENT) {
	   GLuint indices[4] = {2,3,5};
	   glDrawElements (GL_TRIANGLES, 3, GL_INT, indices);
	   //glDrawArrays (GL_TRIANGLES, 0, 3);
     
   }*/
   else if (derefMethod == DRAWELEMENTS) {
      GLuint indices[4] = {0, 1, 3, 4};

      glDrawElements (GL_TRIANGLE_FAN, 4, GL_UNSIGNED_SHORT, indices);
   }
   mouse();
   glFlush ();
}

static void reshape (int w, int h)
{
   glViewport (0, 0, (GLsizei) w, (GLsizei) h);
   glMatrixMode (GL_PROJECTION);
   glLoadIdentity ();
   glOrthof(0.0, (GLfloat) w, 0.0, (GLfloat) h, -1.0, 1.0);
}

static void mouse ()
{
   if (derefMethod == DRAWARRAY) 
        derefMethod = ARRAYELEMENT;
   else if (derefMethod == ARRAYELEMENT) 
        derefMethod = DRAWELEMENTS;
   else if (derefMethod == DRAWELEMENTS) 
        derefMethod = DRAWARRAY;
            //glutPostRedisplay();
}

int VarrayDemo()
{

	init ();
    reshape(WINDOW_WIDTH, WINDOW_HEIGHT);

   return 1; 
}


int VarrayDeinit()
{

   return 1; 
}