OpenGL/util/warp.c

/* Copyright (c) 2001, Stanford University
 * All rights reserved
 *
 * See the file LICENSE.txt for information on redistributing this software.
 */

#include "cr_error.h"
#include "cr_warp.h"

void
crWarpPoint(const float *align, const float *point, float *result)
{
    float w, x, y;

    x = align[0] * point[0] + align[1] * point[1] + align[2];
    y = align[3] * point[0] + align[4] * point[1] + align[5];
    w = align[6] * point[0] + align[7] * point[1] + align[8];

    if (w == 0)
        crError("Crud in alignment matrix --> w == 0. bleh!");

    result[0] = x / w;
    result[1] = y / w;
}