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author | Timothy Pearson <[email protected]> | 2011-12-07 18:20:23 -0600 |
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committer | Timothy Pearson <[email protected]> | 2011-12-07 18:20:23 -0600 |
commit | a9eaee5264ab9f85e01789409ff3c6239262fe82 (patch) | |
tree | 2f3f4114a8a97613c81392c69fa26a2353716f37 /art_rect.c | |
download | libart-lgpl-a9eaee5264ab9f85e01789409ff3c6239262fe82.tar.gz libart-lgpl-a9eaee5264ab9f85e01789409ff3c6239262fe82.zip |
Initial import of libart 2.3.21
Diffstat (limited to 'art_rect.c')
-rw-r--r-- | art_rect.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/art_rect.c b/art_rect.c new file mode 100644 index 0000000..c9dd5b3 --- /dev/null +++ b/art_rect.c @@ -0,0 +1,215 @@ +/* Libart_LGPL - library of basic graphic primitives + * Copyright (C) 1998 Raph Levien + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Library General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Library General Public License for more details. + * + * You should have received a copy of the GNU Library General Public + * License along with this library; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + */ + +#include "config.h" +#include "art_rect.h" + +#include <math.h> + +#ifndef MAX +#define MAX(a, b) (((a) > (b)) ? (a) : (b)) +#endif /* MAX */ + +#ifndef MIN +#define MIN(a, b) (((a) < (b)) ? (a) : (b)) +#endif /* MIN */ + +/* rectangle primitives stolen from gzilla */ + +/** + * art_irect_copy: Make a copy of an integer rectangle. + * @dest: Where the copy is stored. + * @src: The source rectangle. + * + * Copies the rectangle. + **/ +void +art_irect_copy (ArtIRect *dest, const ArtIRect *src) { + dest->x0 = src->x0; + dest->y0 = src->y0; + dest->x1 = src->x1; + dest->y1 = src->y1; +} + +/** + * art_irect_union: Find union of two integer rectangles. + * @dest: Where the result is stored. + * @src1: A source rectangle. + * @src2: Another source rectangle. + * + * Finds the smallest rectangle that includes @src1 and @src2. + **/ +void +art_irect_union (ArtIRect *dest, const ArtIRect *src1, const ArtIRect *src2) { + if (art_irect_empty (src1)) { + art_irect_copy (dest, src2); + } else if (art_irect_empty (src2)) { + art_irect_copy (dest, src1); + } else { + dest->x0 = MIN (src1->x0, src2->x0); + dest->y0 = MIN (src1->y0, src2->y0); + dest->x1 = MAX (src1->x1, src2->x1); + dest->y1 = MAX (src1->y1, src2->y1); + } +} + +/** + * art_irect_intersection: Find intersection of two integer rectangles. + * @dest: Where the result is stored. + * @src1: A source rectangle. + * @src2: Another source rectangle. + * + * Finds the intersection of @src1 and @src2. + **/ +void +art_irect_intersect (ArtIRect *dest, const ArtIRect *src1, const ArtIRect *src2) { + dest->x0 = MAX (src1->x0, src2->x0); + dest->y0 = MAX (src1->y0, src2->y0); + dest->x1 = MIN (src1->x1, src2->x1); + dest->y1 = MIN (src1->y1, src2->y1); +} + +/** + * art_irect_empty: Determine whether integer rectangle is empty. + * @src: The source rectangle. + * + * Return value: TRUE if @src is an empty rectangle, FALSE otherwise. + **/ +int +art_irect_empty (const ArtIRect *src) { + return (src->x1 <= src->x0 || src->y1 <= src->y0); +} + +#if 0 +gboolean irect_point_inside (ArtIRect *rect, GzwPoint *point) { + return (point->x >= rect->x0 && point->y >= rect->y0 && + point->x < rect->x1 && point->y < rect->y1); +} +#endif + +/** + * art_drect_copy: Make a copy of a rectangle. + * @dest: Where the copy is stored. + * @src: The source rectangle. + * + * Copies the rectangle. + **/ +void +art_drect_copy (ArtDRect *dest, const ArtDRect *src) { + dest->x0 = src->x0; + dest->y0 = src->y0; + dest->x1 = src->x1; + dest->y1 = src->y1; +} + +/** + * art_drect_union: Find union of two rectangles. + * @dest: Where the result is stored. + * @src1: A source rectangle. + * @src2: Another source rectangle. + * + * Finds the smallest rectangle that includes @src1 and @src2. + **/ +void +art_drect_union (ArtDRect *dest, const ArtDRect *src1, const ArtDRect *src2) { + if (art_drect_empty (src1)) { + art_drect_copy (dest, src2); + } else if (art_drect_empty (src2)) { + art_drect_copy (dest, src1); + } else { + dest->x0 = MIN (src1->x0, src2->x0); + dest->y0 = MIN (src1->y0, src2->y0); + dest->x1 = MAX (src1->x1, src2->x1); + dest->y1 = MAX (src1->y1, src2->y1); + } +} + +/** + * art_drect_intersection: Find intersection of two rectangles. + * @dest: Where the result is stored. + * @src1: A source rectangle. + * @src2: Another source rectangle. + * + * Finds the intersection of @src1 and @src2. + **/ +void +art_drect_intersect (ArtDRect *dest, const ArtDRect *src1, const ArtDRect *src2) { + dest->x0 = MAX (src1->x0, src2->x0); + dest->y0 = MAX (src1->y0, src2->y0); + dest->x1 = MIN (src1->x1, src2->x1); + dest->y1 = MIN (src1->y1, src2->y1); +} + +/** + * art_irect_empty: Determine whether rectangle is empty. + * @src: The source rectangle. + * + * Return value: TRUE if @src is an empty rectangle, FALSE otherwise. + **/ +int +art_drect_empty (const ArtDRect *src) { + return (src->x1 <= src->x0 || src->y1 <= src->y0); +} + +/** + * art_drect_affine_transform: Affine transform rectangle. + * @dst: Where to store the result. + * @src: The source rectangle. + * @matrix: The affine transformation. + * + * Find the smallest rectangle enclosing the affine transformed @src. + * The result is exactly the affine transformation of @src when + * @matrix specifies a rectilinear affine transformation, otherwise it + * is a conservative approximation. + **/ +void +art_drect_affine_transform (ArtDRect *dst, const ArtDRect *src, const double matrix[6]) +{ + double x00, y00, x10, y10; + double x01, y01, x11, y11; + + x00 = src->x0 * matrix[0] + src->y0 * matrix[2] + matrix[4]; + y00 = src->x0 * matrix[1] + src->y0 * matrix[3] + matrix[5]; + x10 = src->x1 * matrix[0] + src->y0 * matrix[2] + matrix[4]; + y10 = src->x1 * matrix[1] + src->y0 * matrix[3] + matrix[5]; + x01 = src->x0 * matrix[0] + src->y1 * matrix[2] + matrix[4]; + y01 = src->x0 * matrix[1] + src->y1 * matrix[3] + matrix[5]; + x11 = src->x1 * matrix[0] + src->y1 * matrix[2] + matrix[4]; + y11 = src->x1 * matrix[1] + src->y1 * matrix[3] + matrix[5]; + dst->x0 = MIN (MIN (x00, x10), MIN (x01, x11)); + dst->y0 = MIN (MIN (y00, y10), MIN (y01, y11)); + dst->x1 = MAX (MAX (x00, x10), MAX (x01, x11)); + dst->y1 = MAX (MAX (y00, y10), MAX (y01, y11)); +} + +/** + * art_drect_to_irect: Convert rectangle to integer rectangle. + * @dst: Where to store resulting integer rectangle. + * @src: The source rectangle. + * + * Find the smallest integer rectangle that encloses @src. + **/ +void +art_drect_to_irect (ArtIRect *dst, ArtDRect *src) +{ + dst->x0 = floor (src->x0); + dst->y0 = floor (src->y0); + dst->x1 = ceil (src->x1); + dst->y1 = ceil (src->y1); +} |