Forward port cworth's patch to branch.

[fontconfig.git] / src / fcmatrix.c

/*
 * $RCSId: $
 *
 * Copyright © 2000 Tuomas J. Lukka
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of Tuomas Lukka not be used in
 * advertising or publicity pertaining to distribution of the software without
 * specific, written prior permission.  Tuomas Lukka makes no
 * representations about the suitability of this software for any purpose.  It
 * is provided "as is" without express or implied warranty.
 *
 * TUOMAS LUKKA DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL TUOMAS LUKKA BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

#include <math.h>
#include <stdlib.h>
#include <ctype.h>
#include "fcint.h"

FcMatrix    _id = { 1, 0, 0, 1 };
const FcMatrixPtr    FcIdentityMatrix = {
    .storage = FcStorageDynamic,
    .u.dyn = &_id
};

FcMatrix *
FcMatrixCopy (const FcMatrix *mat) 
{
    FcMatrix *r;
    if(!mat) 
	return 0;
    r = (FcMatrix *) malloc (sizeof (*r) );
    if (!r)
	return 0;
    FcMemAlloc (FC_MEM_MATRIX, sizeof (FcMatrix));
    *r = *mat;
    return r;
}

void
FcMatrixPtrDestroy (FcMatrixPtr mi)
{
    if (mi.storage == FcStorageDynamic)
	FcMatrixFree (mi.u.dyn);
}

void
FcMatrixFree (FcMatrix *mat)
{
    if (mat != FcMatrixPtrU(FcIdentityMatrix))
    {
	FcMemFree (FC_MEM_MATRIX, sizeof (FcMatrix));
	free (mat);
    }
}

FcBool
FcMatrixEqual (const FcMatrix *mat1, const FcMatrix *mat2)
{
    if(mat1 == mat2) return FcTrue;
    if(mat1 == 0 || mat2 == 0) return FcFalse;
    return mat1->xx == mat2->xx && 
	   mat1->xy == mat2->xy &&
	   mat1->yx == mat2->yx &&
	   mat1->yy == mat2->yy;
}

void
FcMatrixMultiply (FcMatrix *result, const FcMatrix *a, const FcMatrix *b)
{
    FcMatrix	r;

    r.xx = a->xx * b->xx + a->xy * b->yx;
    r.xy = a->xx * b->xy + a->xy * b->yy;
    r.yx = a->yx * b->xx + a->yy * b->yx;
    r.yy = a->yx * b->xy + a->yy * b->yy;
    *result = r;
}

void
FcMatrixRotate (FcMatrix *m, double c, double s)
{
    FcMatrix	r;

    /*
     * X Coordinate system is upside down, swap to make
     * rotations counterclockwise
     */
    r.xx = c;
    r.xy = -s;
    r.yx = s;
    r.yy = c;
    FcMatrixMultiply (m, &r, m);
}

void
FcMatrixScale (FcMatrix *m, double sx, double sy)
{
    FcMatrix	r;

    r.xx = sx;
    r.xy = 0;
    r.yx = 0;
    r.yy = sy;
    FcMatrixMultiply (m, &r, m);
}

void
FcMatrixShear (FcMatrix *m, double sh, double sv)
{
    FcMatrix	r;

    r.xx = 1;
    r.xy = sh;
    r.yx = sv;
    r.yy = 1;
    FcMatrixMultiply (m, &r, m);
}

static FcMatrix * matrices = 0;
static int matrix_ptr = 0, matrix_count = 0;

void 
FcMatrixClearStatic (void)
{
    matrices = 0;
    matrix_ptr = 0;
    matrix_count = 0;
}

FcMatrix *
FcMatrixPtrU (FcMatrixPtr mi)
{
    switch (mi.storage)
    {
    case FcStorageDynamic:
	return mi.u.dyn;
    case FcStorageStatic:
	return &matrices[mi.u.stat];
    default:
	return 0;

    }
}

FcMatrixPtr
FcMatrixPtrCreateDynamic (FcMatrix *mi)
{
    FcMatrixPtr new;
    new.storage = FcStorageDynamic;
    new.u.dyn = mi;
    return new;
}

FcBool
FcMatrixPrepareSerialize(FcMatrix *m)
{
    matrix_count++;
    return FcTrue;
}

FcMatrixPtr
FcMatrixSerialize(FcMatrix *m)
{
    FcMatrixPtr new;

    if (matrix_count == matrix_ptr)
	return FcMatrixPtrCreateDynamic(0);

    new.storage = FcStorageStatic;
    new.u.stat = matrix_ptr++;
    return new;
}