egl/sfopenvg/riMath.cpp
branchEGL_MERGE
changeset 57 2bf8a359aa2f
child 88 a5a3a8cb368e
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/egl/sfopenvg/riMath.cpp	Wed May 12 11:20:41 2010 +0100
@@ -0,0 +1,75 @@
+/*------------------------------------------------------------------------
+ *
+ * OpenVG 1.1 Reference Implementation
+ * -----------------------------------
+ *
+ * Copyright (c) 2007 The Khronos Group Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and /or associated documentation files
+ * (the "Materials "), to deal in the Materials without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Materials,
+ * and to permit persons to whom the Materials are furnished to do so,
+ * subject to the following conditions: 
+ *
+ * The above copyright notice and this permission notice shall be included 
+ * in all copies or substantial portions of the Materials. 
+ *
+ * THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE MATERIALS OR
+ * THE USE OR OTHER DEALINGS IN THE MATERIALS.
+ *
+ *//**
+ * \file
+ * \brief	Implementation of non-inline matrix functions.
+ * \note	
+ *//*-------------------------------------------------------------------*/
+
+#include "riDefs.h"
+#include "riMath.h"
+
+namespace OpenVGRI
+{
+
+/*-------------------------------------------------------------------*//*!
+* \brief	Inverts a 3x3 matrix. Returns false if the matrix is singular.
+* \param	
+* \return	
+* \note		
+*//*-------------------------------------------------------------------*/
+
+bool Matrix3x3::invert()
+{
+	bool affine = isAffine();
+	RIfloat det00 = matrix[1][1]*matrix[2][2] - matrix[2][1]*matrix[1][2];
+	RIfloat det01 = matrix[2][0]*matrix[1][2] - matrix[1][0]*matrix[2][2];
+	RIfloat det02 = matrix[1][0]*matrix[2][1] - matrix[2][0]*matrix[1][1];
+
+	RIfloat d = matrix[0][0]*det00 + matrix[0][1]*det01 + matrix[0][2]*det02;
+	if( d == 0.0f ) return false;	//singular, leave the matrix unmodified and return false
+	d = 1.0f / d;
+
+	Matrix3x3 t;
+	t[0][0] = d * det00;
+	t[1][0] = d * det01;
+	t[2][0] = d * det02;
+	t[0][1] = d * (matrix[2][1]*matrix[0][2] - matrix[0][1]*matrix[2][2]);
+	t[1][1] = d * (matrix[0][0]*matrix[2][2] - matrix[2][0]*matrix[0][2]);
+	t[2][1] = d * (matrix[2][0]*matrix[0][1] - matrix[0][0]*matrix[2][1]);
+	t[0][2] = d * (matrix[0][1]*matrix[1][2] - matrix[1][1]*matrix[0][2]);
+	t[1][2] = d * (matrix[1][0]*matrix[0][2] - matrix[0][0]*matrix[1][2]);
+	t[2][2] = d * (matrix[0][0]*matrix[1][1] - matrix[1][0]*matrix[0][1]);
+	if(affine)
+		t[2].set(0,0,1);	//affine matrix stays affine
+	*this = t;
+	return true;
+}
+
+//==============================================================================================
+
+}	//namespace OpenVGRI