src/fcmatrix.c

   1 /*
   2  * fontconfig/src/fcmatrix.c
   3  *
   4  * Copyright © 2000 Tuomas J. Lukka
   5  *
   6  * Permission to use, copy, modify, distribute, and sell this software and its
   7  * documentation for any purpose is hereby granted without fee, provided that
   8  * the above copyright notice appear in all copies and that both that
   9  * copyright notice and this permission notice appear in supporting
  10  * documentation, and that the name of Tuomas Lukka not be used in
  11  * advertising or publicity pertaining to distribution of the software without
  12  * specific, written prior permission.  Tuomas Lukka makes no
  13  * representations about the suitability of this software for any purpose.  It
  14  * is provided "as is" without express or implied warranty.
  15  *
  16  * TUOMAS LUKKA DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  17  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  18  * EVENT SHALL TUOMAS LUKKA BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  19  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  20  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  21  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  22  * PERFORMANCE OF THIS SOFTWARE.
  23  */
  24
  25 #include "fcint.h"
  26 #include <math.h>
  27 #include <stdlib.h>
  28 #include <ctype.h>
  29
  30 const FcMatrix    FcIdentityMatrix = { 1, 0, 0, 1 };
  31
  32 FcMatrix *
  33 FcMatrixCopy (const FcMatrix *mat)
  34 {
  35     FcMatrix *r;
  36     if(!mat)
  37         return 0;
  38     r = (FcMatrix *) malloc (sizeof (*r) );
  39     if (!r)
  40         return 0;
  41     FcMemAlloc (FC_MEM_MATRIX, sizeof (FcMatrix));
  42     *r = *mat;
  43     return r;
  44 }
  45
  46 void
  47 FcMatrixFree (FcMatrix *mat)
  48 {
  49     if (mat != &FcIdentityMatrix)
  50     {
  51         FcMemFree (FC_MEM_MATRIX, sizeof (FcMatrix));
  52         free (mat);
  53     }
  54 }
  55
  56 FcBool
  57 FcMatrixEqual (const FcMatrix *mat1, const FcMatrix *mat2)
  58 {
  59     if(mat1 == mat2) return FcTrue;
  60     if(mat1 == 0 || mat2 == 0) return FcFalse;
  61     return mat1->xx == mat2->xx &&
  62            mat1->xy == mat2->xy &&
  63            mat1->yx == mat2->yx &&
  64            mat1->yy == mat2->yy;
  65 }
  66
  67 void
  68 FcMatrixMultiply (FcMatrix *result, const FcMatrix *a, const FcMatrix *b)
  69 {
  70     FcMatrix    r;
  71
  72     r.xx = a->xx * b->xx + a->xy * b->yx;
  73     r.xy = a->xx * b->xy + a->xy * b->yy;
  74     r.yx = a->yx * b->xx + a->yy * b->yx;
  75     r.yy = a->yx * b->xy + a->yy * b->yy;
  76     *result = r;
  77 }
  78
  79 void
  80 FcMatrixRotate (FcMatrix *m, double c, double s)
  81 {
  82     FcMatrix    r;
  83
  84     /*
  85      * X Coordinate system is upside down, swap to make
  86      * rotations counterclockwise
  87      */
  88     r.xx = c;
  89     r.xy = -s;
  90     r.yx = s;
  91     r.yy = c;
  92     FcMatrixMultiply (m, &r, m);
  93 }
  94
  95 void
  96 FcMatrixScale (FcMatrix *m, double sx, double sy)
  97 {
  98     FcMatrix    r;
  99
 100     r.xx = sx;
 101     r.xy = 0;
 102     r.yx = 0;
 103     r.yy = sy;
 104     FcMatrixMultiply (m, &r, m);
 105 }
 106
 107 void
 108 FcMatrixShear (FcMatrix *m, double sh, double sv)
 109 {
 110     FcMatrix    r;
 111
 112     r.xx = 1;
 113     r.xy = sh;
 114     r.yx = sv;
 115     r.yy = 1;
 116     FcMatrixMultiply (m, &r, m);
 117 }
 118 #define __fcmatrix__
 119 #include "fcaliastail.h"
 120 #undef __fcmatrix__