/* * Copyright (c) 2002-2004 LWJGL Project * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are * met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * * Neither the name of 'LWJGL' nor the names of * its contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* * Copyright (c) 2003 Sun Microsystems, Inc. All Rights Reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are * met: * * - Redistribution of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistribution in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * Neither the name of Sun Microsystems, Inc. or the names of * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * This software is provided "AS IS," without a warranty of any kind. ALL * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN * MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR * ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR * DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE * DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF * SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * You acknowledge that this software is not designed or intended for use * in the design, construction, operation or maintenance of any nuclear * facility. */ package com.sun.opengl.impl; import java.nio.IntBuffer; import javax.media.opengl.*; /** * Util.java * <p/> * <p/> * Created 7-jan-2004 * * @author Erik Duijs */ class Util { /** * temp int[] of one for getting an int from some GL functions */ private int[] scratch = new int[1]; /** * Return ceiling of integer division * * @param a * @param b * * @return int */ protected static int ceil(int a, int b) { return (a % b == 0 ? a / b : a / b + 1); } /** * Method compPerPix. * * @param format * * @return int */ protected static int compPerPix(int format) { /* Determine number of components per pixel */ switch ( format ) { case GL.GL_COLOR_INDEX: case GL.GL_STENCIL_INDEX: case GL.GL_DEPTH_COMPONENT: case GL.GL_RED: case GL.GL_GREEN: case GL.GL_BLUE: case GL.GL_ALPHA: case GL.GL_LUMINANCE: return 1; case GL.GL_LUMINANCE_ALPHA: return 2; case GL.GL_RGB: case GL.GL_BGR: return 3; case GL.GL_RGBA: case GL.GL_BGRA: return 4; default : return -1; } } /** * Method nearestPower. * <p/> * Compute the nearest power of 2 number. This algorithm is a little strange, but it works quite well. * * @param value * * @return int */ protected static int nearestPower(int value) { int i; i = 1; /* Error! */ if ( value == 0 ) return -1; for ( ; ; ) { if ( value == 1 ) { return i; } else if ( value == 3 ) { return i << 2; } value >>= 1; i <<= 1; } } /** * Method bytesPerPixel. * * @param format * @param type * * @return int */ protected static int bytesPerPixel(int format, int type) { int n, m; switch ( format ) { case GL.GL_COLOR_INDEX: case GL.GL_STENCIL_INDEX: case GL.GL_DEPTH_COMPONENT: case GL.GL_RED: case GL.GL_GREEN: case GL.GL_BLUE: case GL.GL_ALPHA: case GL.GL_LUMINANCE: n = 1; break; case GL.GL_LUMINANCE_ALPHA: n = 2; break; case GL.GL_RGB: case GL.GL_BGR: n = 3; break; case GL.GL_RGBA: case GL.GL_BGRA: n = 4; break; default : n = 0; } switch ( type ) { case GL.GL_UNSIGNED_BYTE: m = 1; break; case GL.GL_BYTE: m = 1; break; case GL.GL_BITMAP: m = 1; break; case GL.GL_UNSIGNED_SHORT: m = 2; break; case GL.GL_SHORT: m = 2; break; case GL.GL_UNSIGNED_INT: m = 4; break; case GL.GL_INT: m = 4; break; case GL.GL_FLOAT: m = 4; break; default : m = 0; } return n * m; } /** * Convenience method for returning an int, rather than getting it out of a buffer yourself. * * @param what * * @return int */ protected int glGetIntegerv(GL gl, int what) { gl.glGetIntegerv(what, scratch, 0); return scratch[0]; } }