1 /*------------------------------------------------------------------------

     2  *

     3  * OpenVG 1.1 Reference Implementation

     4  * -----------------------------------

     5  *

     6  * Copyright (c) 2007 The Khronos Group Inc.

     7  * Portions copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).

     8  *

     9  * Permission is hereby granted, free of charge, to any person obtaining a

    10  * copy of this software and /or associated documentation files

    11  * (the "Materials "), to deal in the Materials without restriction,

    12  * including without limitation the rights to use, copy, modify, merge,

    13  * publish, distribute, sublicense, and/or sell copies of the Materials,

    14  * and to permit persons to whom the Materials are furnished to do so,

    15  * subject to the following conditions: 

    16  *

    17  * The above copyright notice and this permission notice shall be included 

    18  * in all copies or substantial portions of the Materials. 

    19  *

    20  * THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

    21  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

    22  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.

    23  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,

    24  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR

    25  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE MATERIALS OR

    26  * THE USE OR OTHER DEALINGS IN THE MATERIALS.

    27  *

    28  *//**

    29  * \file

    30  * \brief	Implementation of non-inline matrix functions.

    31  * \note	

    32  *//*-------------------------------------------------------------------*/

    33 

    34 #include "riDefs.h"

    35 #include "riMath.h"

    36 

    37 #if 0

    38 #include <stdio.h>

    39 

    40 static void printMatrix(const Matrix3x3& m)

    41 {

    42     // For tracing a bug in matrix inverse in release-builds.

    43     for(int i = 0; i < 3; i++)

    44     {

    45         printf("[%.4f %.4f %.4f]\n", m[i][0], m[i][1], m[i][2]);

    46     }

    47 }

    48 

    49 #endif

    50 

    51 namespace OpenVGRI

    52 {

    53 

    54 /*-------------------------------------------------------------------*//*!

    55 * \brief	Inverts a 3x3 matrix. Returns false if the matrix is singular.

    56 * \param	

    57 * \return	

    58 * \note		

    59 *//*-------------------------------------------------------------------*/

    60 

    61 bool Matrix3x3::invert()

    62 {

    63     // \todo Save computation on affine matrices?

    64 	bool affine = isAffine();

    65 	RIfloat det00 = matrix[1][1]*matrix[2][2] - matrix[2][1]*matrix[1][2];

    66 	RIfloat det01 = matrix[2][0]*matrix[1][2] - matrix[1][0]*matrix[2][2];

    67 	RIfloat det02 = matrix[1][0]*matrix[2][1] - matrix[2][0]*matrix[1][1];

    68 

    69 	RIfloat d = matrix[0][0]*det00 + matrix[0][1]*det01 + matrix[0][2]*det02;

    70 	if( d == 0.0f ) return false;	//singular, leave the matrix unmodified and return false

    71 	d = 1.0f / d;

    72 

    73 	Matrix3x3 t;

    74 

    75     // \note There is some bug (in GCC?) in accessing matrix elements: If data

    76     // is accessed like: t[i][j], then the following will produce incorrect

    77     // resulst on optimized builds. If the data is accessed through t.matrix,

    78     // then the output is correct. Debug build works correctly, and if print

    79     // calls are inserted, the code also works correctly. The context to get

    80     // this bug appear are fill paints (linear and radial gradient test

    81     // functions).

    82 

    83 	t.matrix[0][0] = d * det00;

    84 	t.matrix[1][0] = d * det01;

    85 	t.matrix[2][0] = d * det02;

    86     //printf("t\n");

    87     //printMatrix(t);

    88 	t.matrix[0][1] = d * (matrix[2][1]*matrix[0][2] - matrix[0][1]*matrix[2][2]);

    89 	t.matrix[1][1] = d * (matrix[0][0]*matrix[2][2] - matrix[2][0]*matrix[0][2]);

    90 	t.matrix[2][1] = d * (matrix[2][0]*matrix[0][1] - matrix[0][0]*matrix[2][1]);

    91 	t.matrix[0][2] = d * (matrix[0][1]*matrix[1][2] - matrix[1][1]*matrix[0][2]);

    92 	t.matrix[1][2] = d * (matrix[1][0]*matrix[0][2] - matrix[0][0]*matrix[1][2]);

    93 	t.matrix[2][2] = d * (matrix[0][0]*matrix[1][1] - matrix[1][0]*matrix[0][1]);

    94 	if(affine)

    95 		t[2].set(0,0,1);	//affine matrix stays affine

    96 	*this = t;

    97 	return true;

    98 }

    99 

   100 //==============================================================================================

   101 

   102 }	//namespace OpenVGRI