/*
 * Copyright (c) 2002 Light Weight Java Game Library 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 'Light Weight Java Game Library' 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.
 */

/**
 * $Id$
 *
 * Win32 math library.
 *
 * @author cix_foo <cix_foo@users.sourceforge.net>
 * @version $Revision$
 */
 
 
#ifdef _DEBUG
#include <stdio.h>
#endif

#include <windows.h>
#include "org_lwjgl_Math_MatrixOpInvert_MatrixOpSafe.h"
#include "MatrixOpCommon.h"

/*
 * Class:     org_lwjgl_Math_MatrixOpInvert_MatrixOpSafe
 * Method:    execute
 * Signature: (IIIIIZIIZ)V
 */
JNIEXPORT void JNICALL Java_org_lwjgl_Math_00024MatrixOpInvert_00024MatrixOpSafe_execute
  (
	JNIEnv * env,
	jobject obj,
	jint sourceAddress,
	jint sourceStride,
	jint numElements,
	jint sourceWidth,
	jint sourceHeight,
	jboolean transposeSource,
	jint destAddress,
	jint destStride,
	jboolean transposeDest
  )
{
        // We are under the assumption that sourceWidth == sourceHeight and the matrix 
        // defined within is invertable
        
        SrcMatrix source  (sourceAddress,  sourceStride, 
                sourceWidth,  sourceHeight,  numElements, transposeSource);
        DstMatrix dest  (destAddress,      destStride,   
                source.width, source.height, source.elements, transposeDest);
    
        float * sourceRecord, * destRecord;
        
        int   temp_side = source.width-1;
        float temp_matrix [temp_side*temp_side];
 
        for (int i = 0; i < source.elements; i++)
        {
            sourceRecord = source.nextRecord();
            destRecord   = dest.nextRecord();

            // calculate the determinant
            float det = determinant(sourceRecord, source.width);
            
#ifdef _DEBUG
            printf("Determinant: %f\n", det);
#endif

            float sign;
            
            for (int col = 0; col < source.width; col++)
            {
                /*
                    Maintain sign:
                    
                    + - + - ...
                    - + - + ..
                    + - + - ..
                    - + - + ..
                    : : : : \
                */
            
                sign = (col & 1) ? -1.0f : 1.0f;
                
                for (int row = 0; row < source.height; row++)
                {
                    // get the sub matrix
                    subMatrix(sourceRecord, source.width, temp_matrix, col, row);
                    
                    // transpose the result
                    destRecord[col + row * source.height] 
                            = (sign / det) * determinant(temp_matrix, temp_side); 
                    
                    // swap signs
                    sign = (sign == 1) ? -1.0f : 1.0f;
                }
            }
    
            dest.writeRecord();
        }
}