src/fcmatrix.c

   1 /*
   2  * $XFree86: $
   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 <math.h>
  26 #include <stdlib.h>
  27 #include <ctype.h>
  28 #include "fcint.h"
  29
  30 FcMatrix *
  31 FcMatrixCopy (const FcMatrix *mat)
  32 {
  33     FcMatrix *r;
  34     if(!mat)
  35         return 0;
  36     r = (FcMatrix *) malloc (sizeof (*r) );
  37     if (!r)
  38         return 0;
  39     FcMemAlloc (FC_MEM_MATRIX, sizeof (FcMatrix));
  40     *r = *mat;
  41     return r;
  42 }
  43
  44 void
  45 FcMatrixFree (FcMatrix *mat)
  46 {
  47     FcMemFree (FC_MEM_MATRIX, sizeof (FcMatrix));
  48     free (mat);
  49 }
  50
  51 FcBool
  52 FcMatrixEqual (const FcMatrix *mat1, const FcMatrix *mat2)
  53 {
  54     if(mat1 == mat2) return FcTrue;
  55     if(mat1 == 0 || mat2 == 0) return FcFalse;
  56     return mat1->xx == mat2->xx &&
  57            mat1->xy == mat2->xy &&
  58            mat1->yx == mat2->yx &&
  59            mat1->yy == mat2->yy;
  60 }
  61
  62 void
  63 FcMatrixMultiply (FcMatrix *result, const FcMatrix *a, const FcMatrix *b)
  64 {
  65     FcMatrix    r;
  66
  67     r.xx = a->xx * b->xx + a->xy * b->yx;
  68     r.xy = a->xx * b->xy + a->xy * b->yy;
  69     r.yx = a->yx * b->xx + a->yy * b->yx;
  70     r.yy = a->yx * b->xy + a->yy * b->yy;
  71     *result = r;
  72 }
  73
  74 void
  75 FcMatrixRotate (FcMatrix *m, double c, double s)
  76 {
  77     FcMatrix    r;
  78
  79     /*
  80      * X Coordinate system is upside down, swap to make
  81      * rotations counterclockwise
  82      */
  83     r.xx = c;
  84     r.xy = -s;
  85     r.yx = s;
  86     r.yy = c;
  87     FcMatrixMultiply (m, &r, m);
  88 }
  89
  90 void
  91 FcMatrixScale (FcMatrix *m, double sx, double sy)
  92 {
  93     FcMatrix    r;
  94
  95     r.xx = sx;
  96     r.xy = 0;
  97     r.yx = 0;
  98     r.yy = sy;
  99     FcMatrixMultiply (m, &r, m);
 100 }
 101
 102 void
 103 FcMatrixShear (FcMatrix *m, double sh, double sv)
 104 {
 105     FcMatrix    r;
 106
 107     r.xx = 1;
 108     r.xy = sh;
 109     r.yx = sv;
 110     r.yy = 1;
 111     FcMatrixMultiply (m, &r, m);
 112 }