1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/qcms/matrix.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,136 @@
1.4 +/* vim: set ts=8 sw=8 noexpandtab: */
1.5 +// qcms
1.6 +// Copyright (C) 2009 Mozilla Foundation
1.7 +// Copyright (C) 1998-2007 Marti Maria
1.8 +//
1.9 +// Permission is hereby granted, free of charge, to any person obtaining
1.10 +// a copy of this software and associated documentation files (the "Software"),
1.11 +// to deal in the Software without restriction, including without limitation
1.12 +// the rights to use, copy, modify, merge, publish, distribute, sublicense,
1.13 +// and/or sell copies of the Software, and to permit persons to whom the Software
1.14 +// is furnished to do so, subject to the following conditions:
1.15 +//
1.16 +// The above copyright notice and this permission notice shall be included in
1.17 +// all copies or substantial portions of the Software.
1.18 +//
1.19 +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
1.20 +// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
1.21 +// THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
1.22 +// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
1.23 +// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
1.24 +// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
1.25 +// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
1.26 +
1.27 +#include <stdlib.h>
1.28 +#include "qcmsint.h"
1.29 +#include "matrix.h"
1.30 +
1.31 +struct vector matrix_eval(struct matrix mat, struct vector v)
1.32 +{
1.33 + struct vector result;
1.34 + result.v[0] = mat.m[0][0]*v.v[0] + mat.m[0][1]*v.v[1] + mat.m[0][2]*v.v[2];
1.35 + result.v[1] = mat.m[1][0]*v.v[0] + mat.m[1][1]*v.v[1] + mat.m[1][2]*v.v[2];
1.36 + result.v[2] = mat.m[2][0]*v.v[0] + mat.m[2][1]*v.v[1] + mat.m[2][2]*v.v[2];
1.37 + return result;
1.38 +}
1.39 +
1.40 +//XXX: should probably pass by reference and we could
1.41 +//probably reuse this computation in matrix_invert
1.42 +float matrix_det(struct matrix mat)
1.43 +{
1.44 + float det;
1.45 + det = mat.m[0][0]*mat.m[1][1]*mat.m[2][2] +
1.46 + mat.m[0][1]*mat.m[1][2]*mat.m[2][0] +
1.47 + mat.m[0][2]*mat.m[1][0]*mat.m[2][1] -
1.48 + mat.m[0][0]*mat.m[1][2]*mat.m[2][1] -
1.49 + mat.m[0][1]*mat.m[1][0]*mat.m[2][2] -
1.50 + mat.m[0][2]*mat.m[1][1]*mat.m[2][0];
1.51 + return det;
1.52 +}
1.53 +
1.54 +/* from pixman and cairo and Mathematics for Game Programmers */
1.55 +/* lcms uses gauss-jordan elimination with partial pivoting which is
1.56 + * less efficient and not as numerically stable. See Mathematics for
1.57 + * Game Programmers. */
1.58 +struct matrix matrix_invert(struct matrix mat)
1.59 +{
1.60 + struct matrix dest_mat;
1.61 + int i,j;
1.62 + static int a[3] = { 2, 2, 1 };
1.63 + static int b[3] = { 1, 0, 0 };
1.64 +
1.65 + /* inv (A) = 1/det (A) * adj (A) */
1.66 + float det = matrix_det(mat);
1.67 +
1.68 + if (det == 0) {
1.69 + dest_mat.invalid = true;
1.70 + } else {
1.71 + dest_mat.invalid = false;
1.72 + }
1.73 +
1.74 + det = 1/det;
1.75 +
1.76 + for (j = 0; j < 3; j++) {
1.77 + for (i = 0; i < 3; i++) {
1.78 + double p;
1.79 + int ai = a[i];
1.80 + int aj = a[j];
1.81 + int bi = b[i];
1.82 + int bj = b[j];
1.83 +
1.84 + p = mat.m[ai][aj] * mat.m[bi][bj] -
1.85 + mat.m[ai][bj] * mat.m[bi][aj];
1.86 + if (((i + j) & 1) != 0)
1.87 + p = -p;
1.88 +
1.89 + dest_mat.m[j][i] = det * p;
1.90 + }
1.91 + }
1.92 + return dest_mat;
1.93 +}
1.94 +
1.95 +struct matrix matrix_identity(void)
1.96 +{
1.97 + struct matrix i;
1.98 + i.m[0][0] = 1;
1.99 + i.m[0][1] = 0;
1.100 + i.m[0][2] = 0;
1.101 + i.m[1][0] = 0;
1.102 + i.m[1][1] = 1;
1.103 + i.m[1][2] = 0;
1.104 + i.m[2][0] = 0;
1.105 + i.m[2][1] = 0;
1.106 + i.m[2][2] = 1;
1.107 + i.invalid = false;
1.108 + return i;
1.109 +}
1.110 +
1.111 +struct matrix matrix_invalid(void)
1.112 +{
1.113 + struct matrix inv = matrix_identity();
1.114 + inv.invalid = true;
1.115 + return inv;
1.116 +}
1.117 +
1.118 +
1.119 +/* from pixman */
1.120 +/* MAT3per... */
1.121 +struct matrix matrix_multiply(struct matrix a, struct matrix b)
1.122 +{
1.123 + struct matrix result;
1.124 + int dx, dy;
1.125 + int o;
1.126 + for (dy = 0; dy < 3; dy++) {
1.127 + for (dx = 0; dx < 3; dx++) {
1.128 + double v = 0;
1.129 + for (o = 0; o < 3; o++) {
1.130 + v += a.m[dy][o] * b.m[o][dx];
1.131 + }
1.132 + result.m[dy][dx] = v;
1.133 + }
1.134 + }
1.135 + result.invalid = a.invalid || b.invalid;
1.136 + return result;
1.137 +}
1.138 +
1.139 +
