gfx/qcms/matrix.c@97036ab72558 (annotated)
gfx/qcms/matrix.c
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | /* vim: set ts=8 sw=8 noexpandtab: */ |
| michael@0 | 2 | // qcms |
| michael@0 | 3 | // Copyright (C) 2009 Mozilla Foundation |
| michael@0 | 4 | // Copyright (C) 1998-2007 Marti Maria |
| michael@0 | 5 | // |
| michael@0 | 6 | // Permission is hereby granted, free of charge, to any person obtaining |
| michael@0 | 7 | // a copy of this software and associated documentation files (the "Software"), |
| michael@0 | 8 | // to deal in the Software without restriction, including without limitation |
| michael@0 | 9 | // the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| michael@0 | 10 | // and/or sell copies of the Software, and to permit persons to whom the Software |
| michael@0 | 11 | // is furnished to do so, subject to the following conditions: |
| michael@0 | 12 | // |
| michael@0 | 13 | // The above copyright notice and this permission notice shall be included in |
| michael@0 | 14 | // all copies or substantial portions of the Software. |
| michael@0 | 15 | // |
| michael@0 | 16 | // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| michael@0 | 17 | // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO |
| michael@0 | 18 | // THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
| michael@0 | 19 | // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE |
| michael@0 | 20 | // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION |
| michael@0 | 21 | // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION |
| michael@0 | 22 | // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| michael@0 | 23 | |
| michael@0 | 24 | #include <stdlib.h> |
| michael@0 | 25 | #include "qcmsint.h" |
| michael@0 | 26 | #include "matrix.h" |
| michael@0 | 27 | |
| michael@0 | 28 | struct vector matrix_eval(struct matrix mat, struct vector v) |
| michael@0 | 29 | { |
| michael@0 | 30 | struct vector result; |
| michael@0 | 31 | result.v[0] = mat.m[0][0]*v.v[0] + mat.m[0][1]*v.v[1] + mat.m[0][2]*v.v[2]; |
| michael@0 | 32 | result.v[1] = mat.m[1][0]*v.v[0] + mat.m[1][1]*v.v[1] + mat.m[1][2]*v.v[2]; |
| michael@0 | 33 | result.v[2] = mat.m[2][0]*v.v[0] + mat.m[2][1]*v.v[1] + mat.m[2][2]*v.v[2]; |
| michael@0 | 34 | return result; |
| michael@0 | 35 | } |
| michael@0 | 36 | |
| michael@0 | 37 | //XXX: should probably pass by reference and we could |
| michael@0 | 38 | //probably reuse this computation in matrix_invert |
| michael@0 | 39 | float matrix_det(struct matrix mat) |
| michael@0 | 40 | { |
| michael@0 | 41 | float det; |
| michael@0 | 42 | det = mat.m[0][0]*mat.m[1][1]*mat.m[2][2] + |
| michael@0 | 43 | mat.m[0][1]*mat.m[1][2]*mat.m[2][0] + |
| michael@0 | 44 | mat.m[0][2]*mat.m[1][0]*mat.m[2][1] - |
| michael@0 | 45 | mat.m[0][0]*mat.m[1][2]*mat.m[2][1] - |
| michael@0 | 46 | mat.m[0][1]*mat.m[1][0]*mat.m[2][2] - |
| michael@0 | 47 | mat.m[0][2]*mat.m[1][1]*mat.m[2][0]; |
| michael@0 | 48 | return det; |
| michael@0 | 49 | } |
| michael@0 | 50 | |
| michael@0 | 51 | /* from pixman and cairo and Mathematics for Game Programmers */ |
| michael@0 | 52 | /* lcms uses gauss-jordan elimination with partial pivoting which is |
| michael@0 | 53 | * less efficient and not as numerically stable. See Mathematics for |
| michael@0 | 54 | * Game Programmers. */ |
| michael@0 | 55 | struct matrix matrix_invert(struct matrix mat) |
| michael@0 | 56 | { |
| michael@0 | 57 | struct matrix dest_mat; |
| michael@0 | 58 | int i,j; |
| michael@0 | 59 | static int a[3] = { 2, 2, 1 }; |
| michael@0 | 60 | static int b[3] = { 1, 0, 0 }; |
| michael@0 | 61 | |
| michael@0 | 62 | /* inv (A) = 1/det (A) * adj (A) */ |
| michael@0 | 63 | float det = matrix_det(mat); |
| michael@0 | 64 | |
| michael@0 | 65 | if (det == 0) { |
| michael@0 | 66 | dest_mat.invalid = true; |
| michael@0 | 67 | } else { |
| michael@0 | 68 | dest_mat.invalid = false; |
| michael@0 | 69 | } |
| michael@0 | 70 | |
| michael@0 | 71 | det = 1/det; |
| michael@0 | 72 | |
| michael@0 | 73 | for (j = 0; j < 3; j++) { |
| michael@0 | 74 | for (i = 0; i < 3; i++) { |
| michael@0 | 75 | double p; |
| michael@0 | 76 | int ai = a[i]; |
| michael@0 | 77 | int aj = a[j]; |
| michael@0 | 78 | int bi = b[i]; |
| michael@0 | 79 | int bj = b[j]; |
| michael@0 | 80 | |
| michael@0 | 81 | p = mat.m[ai][aj] * mat.m[bi][bj] - |
| michael@0 | 82 | mat.m[ai][bj] * mat.m[bi][aj]; |
| michael@0 | 83 | if (((i + j) & 1) != 0) |
| michael@0 | 84 | p = -p; |
| michael@0 | 85 | |
| michael@0 | 86 | dest_mat.m[j][i] = det * p; |
| michael@0 | 87 | } |
| michael@0 | 88 | } |
| michael@0 | 89 | return dest_mat; |
| michael@0 | 90 | } |
| michael@0 | 91 | |
| michael@0 | 92 | struct matrix matrix_identity(void) |
| michael@0 | 93 | { |
| michael@0 | 94 | struct matrix i; |
| michael@0 | 95 | i.m[0][0] = 1; |
| michael@0 | 96 | i.m[0][1] = 0; |
| michael@0 | 97 | i.m[0][2] = 0; |
| michael@0 | 98 | i.m[1][0] = 0; |
| michael@0 | 99 | i.m[1][1] = 1; |
| michael@0 | 100 | i.m[1][2] = 0; |
| michael@0 | 101 | i.m[2][0] = 0; |
| michael@0 | 102 | i.m[2][1] = 0; |
| michael@0 | 103 | i.m[2][2] = 1; |
| michael@0 | 104 | i.invalid = false; |
| michael@0 | 105 | return i; |
| michael@0 | 106 | } |
| michael@0 | 107 | |
| michael@0 | 108 | struct matrix matrix_invalid(void) |
| michael@0 | 109 | { |
| michael@0 | 110 | struct matrix inv = matrix_identity(); |
| michael@0 | 111 | inv.invalid = true; |
| michael@0 | 112 | return inv; |
| michael@0 | 113 | } |
| michael@0 | 114 | |
| michael@0 | 115 | |
| michael@0 | 116 | /* from pixman */ |
| michael@0 | 117 | /* MAT3per... */ |
| michael@0 | 118 | struct matrix matrix_multiply(struct matrix a, struct matrix b) |
| michael@0 | 119 | { |
| michael@0 | 120 | struct matrix result; |
| michael@0 | 121 | int dx, dy; |
| michael@0 | 122 | int o; |
| michael@0 | 123 | for (dy = 0; dy < 3; dy++) { |
| michael@0 | 124 | for (dx = 0; dx < 3; dx++) { |
| michael@0 | 125 | double v = 0; |
| michael@0 | 126 | for (o = 0; o < 3; o++) { |
| michael@0 | 127 | v += a.m[dy][o] * b.m[o][dx]; |
| michael@0 | 128 | } |
| michael@0 | 129 | result.m[dy][dx] = v; |
| michael@0 | 130 | } |
| michael@0 | 131 | } |
| michael@0 | 132 | result.invalid = a.invalid || b.invalid; |
| michael@0 | 133 | return result; |
| michael@0 | 134 | } |
| michael@0 | 135 | |
| michael@0 | 136 |
