/* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */ /* cairo - a vector graphics library with display and print output * * Copyright © 2002 University of Southern California * Copyright © 2005 Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it either under the terms of the GNU Lesser General Public * License version 2.1 as published by the Free Software Foundation * (the "LGPL") or, at your option, under the terms of the Mozilla * Public License Version 1.1 (the "MPL"). If you do not alter this * notice, a recipient may use your version of this file under either * the MPL or the LGPL. * * You should have received a copy of the LGPL along with this library * in the file COPYING-LGPL-2.1; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA * You should have received a copy of the MPL along with this library * in the file COPYING-MPL-1.1 * * The contents of this file are subject to the Mozilla Public License * Version 1.1 (the "License"); you may not use this file except in * compliance with the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY * OF ANY KIND, either express or implied. See the LGPL or the MPL for * the specific language governing rights and limitations. * * The Original Code is the cairo graphics library. * * The Initial Developer of the Original Code is University of Southern * California. * * Contributor(s): * Carl D. Worth */ #include "cairoint.h" #include "cairo-box-inline.h" #include "cairo-error-private.h" #include "cairo-list-inline.h" #include "cairo-path-fixed-private.h" #include "cairo-slope-private.h" static cairo_status_t _cairo_path_fixed_add (cairo_path_fixed_t *path, cairo_path_op_t op, const cairo_point_t *points, int num_points); static void _cairo_path_fixed_add_buf (cairo_path_fixed_t *path, cairo_path_buf_t *buf); static cairo_path_buf_t * _cairo_path_buf_create (int size_ops, int size_points); static void _cairo_path_buf_destroy (cairo_path_buf_t *buf); static void _cairo_path_buf_add_op (cairo_path_buf_t *buf, cairo_path_op_t op); static void _cairo_path_buf_add_points (cairo_path_buf_t *buf, const cairo_point_t *points, int num_points); void _cairo_path_fixed_init (cairo_path_fixed_t *path) { VG (VALGRIND_MAKE_MEM_UNDEFINED (path, sizeof (cairo_path_fixed_t))); cairo_list_init (&path->buf.base.link); path->buf.base.num_ops = 0; path->buf.base.num_points = 0; path->buf.base.size_ops = ARRAY_LENGTH (path->buf.op); path->buf.base.size_points = ARRAY_LENGTH (path->buf.points); path->buf.base.op = path->buf.op; path->buf.base.points = path->buf.points; path->current_point.x = 0; path->current_point.y = 0; path->last_move_point = path->current_point; path->has_current_point = FALSE; path->needs_move_to = TRUE; path->has_extents = FALSE; path->has_curve_to = FALSE; path->stroke_is_rectilinear = TRUE; path->fill_is_rectilinear = TRUE; path->fill_maybe_region = TRUE; path->fill_is_empty = TRUE; path->extents.p1.x = path->extents.p1.y = 0; path->extents.p2.x = path->extents.p2.y = 0; } cairo_status_t _cairo_path_fixed_init_copy (cairo_path_fixed_t *path, const cairo_path_fixed_t *other) { cairo_path_buf_t *buf, *other_buf; unsigned int num_points, num_ops; VG (VALGRIND_MAKE_MEM_UNDEFINED (path, sizeof (cairo_path_fixed_t))); cairo_list_init (&path->buf.base.link); path->buf.base.op = path->buf.op; path->buf.base.points = path->buf.points; path->buf.base.size_ops = ARRAY_LENGTH (path->buf.op); path->buf.base.size_points = ARRAY_LENGTH (path->buf.points); path->current_point = other->current_point; path->last_move_point = other->last_move_point; path->has_current_point = other->has_current_point; path->needs_move_to = other->needs_move_to; path->has_extents = other->has_extents; path->has_curve_to = other->has_curve_to; path->stroke_is_rectilinear = other->stroke_is_rectilinear; path->fill_is_rectilinear = other->fill_is_rectilinear; path->fill_maybe_region = other->fill_maybe_region; path->fill_is_empty = other->fill_is_empty; path->extents = other->extents; path->buf.base.num_ops = other->buf.base.num_ops; path->buf.base.num_points = other->buf.base.num_points; memcpy (path->buf.op, other->buf.base.op, other->buf.base.num_ops * sizeof (other->buf.op[0])); memcpy (path->buf.points, other->buf.points, other->buf.base.num_points * sizeof (other->buf.points[0])); num_points = num_ops = 0; for (other_buf = cairo_path_buf_next (cairo_path_head (other)); other_buf != cairo_path_head (other); other_buf = cairo_path_buf_next (other_buf)) { num_ops += other_buf->num_ops; num_points += other_buf->num_points; } if (num_ops) { buf = _cairo_path_buf_create (num_ops, num_points); if (unlikely (buf == NULL)) { _cairo_path_fixed_fini (path); return _cairo_error (CAIRO_STATUS_NO_MEMORY); } for (other_buf = cairo_path_buf_next (cairo_path_head (other)); other_buf != cairo_path_head (other); other_buf = cairo_path_buf_next (other_buf)) { memcpy (buf->op + buf->num_ops, other_buf->op, other_buf->num_ops * sizeof (buf->op[0])); buf->num_ops += other_buf->num_ops; memcpy (buf->points + buf->num_points, other_buf->points, other_buf->num_points * sizeof (buf->points[0])); buf->num_points += other_buf->num_points; } _cairo_path_fixed_add_buf (path, buf); } return CAIRO_STATUS_SUCCESS; } unsigned long _cairo_path_fixed_hash (const cairo_path_fixed_t *path) { unsigned long hash = _CAIRO_HASH_INIT_VALUE; const cairo_path_buf_t *buf; unsigned int count; count = 0; cairo_path_foreach_buf_start (buf, path) { hash = _cairo_hash_bytes (hash, buf->op, buf->num_ops * sizeof (buf->op[0])); count += buf->num_ops; } cairo_path_foreach_buf_end (buf, path); hash = _cairo_hash_bytes (hash, &count, sizeof (count)); count = 0; cairo_path_foreach_buf_start (buf, path) { hash = _cairo_hash_bytes (hash, buf->points, buf->num_points * sizeof (buf->points[0])); count += buf->num_points; } cairo_path_foreach_buf_end (buf, path); hash = _cairo_hash_bytes (hash, &count, sizeof (count)); return hash; } unsigned long _cairo_path_fixed_size (const cairo_path_fixed_t *path) { const cairo_path_buf_t *buf; int num_points, num_ops; num_ops = num_points = 0; cairo_path_foreach_buf_start (buf, path) { num_ops += buf->num_ops; num_points += buf->num_points; } cairo_path_foreach_buf_end (buf, path); return num_ops * sizeof (buf->op[0]) + num_points * sizeof (buf->points[0]); } cairo_bool_t _cairo_path_fixed_equal (const cairo_path_fixed_t *a, const cairo_path_fixed_t *b) { const cairo_path_buf_t *buf_a, *buf_b; const cairo_path_op_t *ops_a, *ops_b; const cairo_point_t *points_a, *points_b; int num_points_a, num_ops_a; int num_points_b, num_ops_b; if (a == b) return TRUE; /* use the flags to quickly differentiate based on contents */ if (a->has_curve_to != b->has_curve_to) { return FALSE; } if (a->extents.p1.x != b->extents.p1.x || a->extents.p1.y != b->extents.p1.y || a->extents.p2.x != b->extents.p2.x || a->extents.p2.y != b->extents.p2.y) { return FALSE; } num_ops_a = num_points_a = 0; cairo_path_foreach_buf_start (buf_a, a) { num_ops_a += buf_a->num_ops; num_points_a += buf_a->num_points; } cairo_path_foreach_buf_end (buf_a, a); num_ops_b = num_points_b = 0; cairo_path_foreach_buf_start (buf_b, b) { num_ops_b += buf_b->num_ops; num_points_b += buf_b->num_points; } cairo_path_foreach_buf_end (buf_b, b); if (num_ops_a == 0 && num_ops_b == 0) return TRUE; if (num_ops_a != num_ops_b || num_points_a != num_points_b) return FALSE; buf_a = cairo_path_head (a); num_points_a = buf_a->num_points; num_ops_a = buf_a->num_ops; ops_a = buf_a->op; points_a = buf_a->points; buf_b = cairo_path_head (b); num_points_b = buf_b->num_points; num_ops_b = buf_b->num_ops; ops_b = buf_b->op; points_b = buf_b->points; while (TRUE) { int num_ops = MIN (num_ops_a, num_ops_b); int num_points = MIN (num_points_a, num_points_b); if (memcmp (ops_a, ops_b, num_ops * sizeof (cairo_path_op_t))) return FALSE; if (memcmp (points_a, points_b, num_points * sizeof (cairo_point_t))) return FALSE; num_ops_a -= num_ops; ops_a += num_ops; num_points_a -= num_points; points_a += num_points; if (num_ops_a == 0 || num_points_a == 0) { if (num_ops_a || num_points_a) return FALSE; buf_a = cairo_path_buf_next (buf_a); if (buf_a == cairo_path_head (a)) break; num_points_a = buf_a->num_points; num_ops_a = buf_a->num_ops; ops_a = buf_a->op; points_a = buf_a->points; } num_ops_b -= num_ops; ops_b += num_ops; num_points_b -= num_points; points_b += num_points; if (num_ops_b == 0 || num_points_b == 0) { if (num_ops_b || num_points_b) return FALSE; buf_b = cairo_path_buf_next (buf_b); if (buf_b == cairo_path_head (b)) break; num_points_b = buf_b->num_points; num_ops_b = buf_b->num_ops; ops_b = buf_b->op; points_b = buf_b->points; } } return TRUE; } cairo_path_fixed_t * _cairo_path_fixed_create (void) { cairo_path_fixed_t *path; path = malloc (sizeof (cairo_path_fixed_t)); if (!path) { _cairo_error_throw (CAIRO_STATUS_NO_MEMORY); return NULL; } _cairo_path_fixed_init (path); return path; } void _cairo_path_fixed_fini (cairo_path_fixed_t *path) { cairo_path_buf_t *buf; buf = cairo_path_buf_next (cairo_path_head (path)); while (buf != cairo_path_head (path)) { cairo_path_buf_t *this = buf; buf = cairo_path_buf_next (buf); _cairo_path_buf_destroy (this); } VG (VALGRIND_MAKE_MEM_UNDEFINED (path, sizeof (cairo_path_fixed_t))); } void _cairo_path_fixed_destroy (cairo_path_fixed_t *path) { _cairo_path_fixed_fini (path); free (path); } static cairo_path_op_t _cairo_path_fixed_last_op (cairo_path_fixed_t *path) { cairo_path_buf_t *buf; buf = cairo_path_tail (path); assert (buf->num_ops != 0); return buf->op[buf->num_ops - 1]; } static inline const cairo_point_t * _cairo_path_fixed_penultimate_point (cairo_path_fixed_t *path) { cairo_path_buf_t *buf; buf = cairo_path_tail (path); if (likely (buf->num_points >= 2)) { return &buf->points[buf->num_points - 2]; } else { cairo_path_buf_t *prev_buf = cairo_path_buf_prev (buf); assert (prev_buf->num_points >= 2 - buf->num_points); return &prev_buf->points[prev_buf->num_points - (2 - buf->num_points)]; } } static void _cairo_path_fixed_drop_line_to (cairo_path_fixed_t *path) { cairo_path_buf_t *buf; assert (_cairo_path_fixed_last_op (path) == CAIRO_PATH_OP_LINE_TO); buf = cairo_path_tail (path); buf->num_points--; buf->num_ops--; } cairo_status_t _cairo_path_fixed_move_to (cairo_path_fixed_t *path, cairo_fixed_t x, cairo_fixed_t y) { _cairo_path_fixed_new_sub_path (path); path->has_current_point = TRUE; path->current_point.x = x; path->current_point.y = y; path->last_move_point = path->current_point; return CAIRO_STATUS_SUCCESS; } static cairo_status_t _cairo_path_fixed_move_to_apply (cairo_path_fixed_t *path) { if (likely (! path->needs_move_to)) return CAIRO_STATUS_SUCCESS; path->needs_move_to = FALSE; if (path->has_extents) { _cairo_box_add_point (&path->extents, &path->current_point); } else { _cairo_box_set (&path->extents, &path->current_point, &path->current_point); path->has_extents = TRUE; } if (path->fill_maybe_region) { path->fill_maybe_region = _cairo_fixed_is_integer (path->current_point.x) && _cairo_fixed_is_integer (path->current_point.y); } path->last_move_point = path->current_point; return _cairo_path_fixed_add (path, CAIRO_PATH_OP_MOVE_TO, &path->current_point, 1); } void _cairo_path_fixed_new_sub_path (cairo_path_fixed_t *path) { if (! path->needs_move_to) { /* If the current subpath doesn't need_move_to, it contains at least one command */ if (path->fill_is_rectilinear) { /* Implicitly close for fill */ path->fill_is_rectilinear = path->current_point.x == path->last_move_point.x || path->current_point.y == path->last_move_point.y; path->fill_maybe_region &= path->fill_is_rectilinear; } path->needs_move_to = TRUE; } path->has_current_point = FALSE; } cairo_status_t _cairo_path_fixed_rel_move_to (cairo_path_fixed_t *path, cairo_fixed_t dx, cairo_fixed_t dy) { if (unlikely (! path->has_current_point)) return _cairo_error (CAIRO_STATUS_NO_CURRENT_POINT); return _cairo_path_fixed_move_to (path, path->current_point.x + dx, path->current_point.y + dy); } cairo_status_t _cairo_path_fixed_line_to (cairo_path_fixed_t *path, cairo_fixed_t x, cairo_fixed_t y) { cairo_status_t status; cairo_point_t point; point.x = x; point.y = y; /* When there is not yet a current point, the line_to operation * becomes a move_to instead. Note: We have to do this by * explicitly calling into _cairo_path_fixed_move_to to ensure * that the last_move_point state is updated properly. */ if (! path->has_current_point) return _cairo_path_fixed_move_to (path, point.x, point.y); status = _cairo_path_fixed_move_to_apply (path); if (unlikely (status)) return status; /* If the previous op was but the initial MOVE_TO and this segment * is degenerate, then we can simply skip this point. Note that * a move-to followed by a degenerate line-to is a valid path for * stroking, but at all other times is simply a degenerate segment. */ if (_cairo_path_fixed_last_op (path) != CAIRO_PATH_OP_MOVE_TO) { if (x == path->current_point.x && y == path->current_point.y) return CAIRO_STATUS_SUCCESS; } /* If the previous op was also a LINE_TO with the same gradient, * then just change its end-point rather than adding a new op. */ if (_cairo_path_fixed_last_op (path) == CAIRO_PATH_OP_LINE_TO) { const cairo_point_t *p; p = _cairo_path_fixed_penultimate_point (path); if (p->x == path->current_point.x && p->y == path->current_point.y) { /* previous line element was degenerate, replace */ _cairo_path_fixed_drop_line_to (path); } else { cairo_slope_t prev, self; _cairo_slope_init (&prev, p, &path->current_point); _cairo_slope_init (&self, &path->current_point, &point); if (_cairo_slope_equal (&prev, &self) && /* cannot trim anti-parallel segments whilst stroking */ ! _cairo_slope_backwards (&prev, &self)) { _cairo_path_fixed_drop_line_to (path); /* In this case the flags might be more restrictive than * what we actually need. * When changing the flags definition we should check if * changing the line_to point can affect them. */ } } } if (path->stroke_is_rectilinear) { path->stroke_is_rectilinear = path->current_point.x == x || path->current_point.y == y; path->fill_is_rectilinear &= path->stroke_is_rectilinear; path->fill_maybe_region &= path->fill_is_rectilinear; if (path->fill_maybe_region) { path->fill_maybe_region = _cairo_fixed_is_integer (x) && _cairo_fixed_is_integer (y); } if (path->fill_is_empty) { path->fill_is_empty = path->current_point.x == x && path->current_point.y == y; } } path->current_point = point; _cairo_box_add_point (&path->extents, &point); return _cairo_path_fixed_add (path, CAIRO_PATH_OP_LINE_TO, &point, 1); } cairo_status_t _cairo_path_fixed_rel_line_to (cairo_path_fixed_t *path, cairo_fixed_t dx, cairo_fixed_t dy) { if (unlikely (! path->has_current_point)) return _cairo_error (CAIRO_STATUS_NO_CURRENT_POINT); return _cairo_path_fixed_line_to (path, path->current_point.x + dx, path->current_point.y + dy); } cairo_status_t _cairo_path_fixed_curve_to (cairo_path_fixed_t *path, cairo_fixed_t x0, cairo_fixed_t y0, cairo_fixed_t x1, cairo_fixed_t y1, cairo_fixed_t x2, cairo_fixed_t y2) { cairo_status_t status; cairo_point_t point[3]; /* If this curves does not move, replace it with a line-to. * This frequently happens with rounded-rectangles and r==0. */ if (path->current_point.x == x2 && path->current_point.y == y2) { if (x1 == x2 && x0 == x2 && y1 == y2 && y0 == y2) return _cairo_path_fixed_line_to (path, x2, y2); /* We may want to check for the absence of a cusp, in which case * we can also replace the curve-to with a line-to. */ } /* make sure subpaths are started properly */ if (! path->has_current_point) { status = _cairo_path_fixed_move_to (path, x0, y0); assert (status == CAIRO_STATUS_SUCCESS); } status = _cairo_path_fixed_move_to_apply (path); if (unlikely (status)) return status; /* If the previous op was a degenerate LINE_TO, drop it. */ if (_cairo_path_fixed_last_op (path) == CAIRO_PATH_OP_LINE_TO) { const cairo_point_t *p; p = _cairo_path_fixed_penultimate_point (path); if (p->x == path->current_point.x && p->y == path->current_point.y) { /* previous line element was degenerate, replace */ _cairo_path_fixed_drop_line_to (path); } } point[0].x = x0; point[0].y = y0; point[1].x = x1; point[1].y = y1; point[2].x = x2; point[2].y = y2; _cairo_box_add_curve_to (&path->extents, &path->current_point, &point[0], &point[1], &point[2]); path->current_point = point[2]; path->has_curve_to = TRUE; path->stroke_is_rectilinear = FALSE; path->fill_is_rectilinear = FALSE; path->fill_maybe_region = FALSE; path->fill_is_empty = FALSE; return _cairo_path_fixed_add (path, CAIRO_PATH_OP_CURVE_TO, point, 3); } cairo_status_t _cairo_path_fixed_rel_curve_to (cairo_path_fixed_t *path, cairo_fixed_t dx0, cairo_fixed_t dy0, cairo_fixed_t dx1, cairo_fixed_t dy1, cairo_fixed_t dx2, cairo_fixed_t dy2) { if (unlikely (! path->has_current_point)) return _cairo_error (CAIRO_STATUS_NO_CURRENT_POINT); return _cairo_path_fixed_curve_to (path, path->current_point.x + dx0, path->current_point.y + dy0, path->current_point.x + dx1, path->current_point.y + dy1, path->current_point.x + dx2, path->current_point.y + dy2); } cairo_status_t _cairo_path_fixed_close_path (cairo_path_fixed_t *path) { cairo_status_t status; if (! path->has_current_point) return CAIRO_STATUS_SUCCESS; /* * Add a line_to, to compute flags and solve any degeneracy. * It will be removed later (if it was actually added). */ status = _cairo_path_fixed_line_to (path, path->last_move_point.x, path->last_move_point.y); if (unlikely (status)) return status; /* * If the command used to close the path is a line_to, drop it. * We must check that last command is actually a line_to, * because the path could have been closed with a curve_to (and * the previous line_to not added as it would be degenerate). */ if (_cairo_path_fixed_last_op (path) == CAIRO_PATH_OP_LINE_TO) _cairo_path_fixed_drop_line_to (path); path->needs_move_to = TRUE; /* After close_path, add an implicit move_to */ return _cairo_path_fixed_add (path, CAIRO_PATH_OP_CLOSE_PATH, NULL, 0); } cairo_bool_t _cairo_path_fixed_get_current_point (cairo_path_fixed_t *path, cairo_fixed_t *x, cairo_fixed_t *y) { if (! path->has_current_point) return FALSE; *x = path->current_point.x; *y = path->current_point.y; return TRUE; } static cairo_status_t _cairo_path_fixed_add (cairo_path_fixed_t *path, cairo_path_op_t op, const cairo_point_t *points, int num_points) { cairo_path_buf_t *buf = cairo_path_tail (path); if (buf->num_ops + 1 > buf->size_ops || buf->num_points + num_points > buf->size_points) { buf = _cairo_path_buf_create (buf->num_ops * 2, buf->num_points * 2); if (unlikely (buf == NULL)) return _cairo_error (CAIRO_STATUS_NO_MEMORY); _cairo_path_fixed_add_buf (path, buf); } if (WATCH_PATH) { const char *op_str[] = { "move-to", "line-to", "curve-to", "close-path", }; char buf[1024]; int len = 0; int i; len += snprintf (buf + len, sizeof (buf), "["); for (i = 0; i < num_points; i++) { if (i != 0) len += snprintf (buf + len, sizeof (buf), " "); len += snprintf (buf + len, sizeof (buf), "(%f, %f)", _cairo_fixed_to_double (points[i].x), _cairo_fixed_to_double (points[i].y)); } len += snprintf (buf + len, sizeof (buf), "]"); #define STRINGIFYFLAG(x) (path->x ? #x " " : "") fprintf (stderr, "_cairo_path_fixed_add (%s, %s) [%s%s%s%s%s%s%s%s]\n", op_str[(int) op], buf, STRINGIFYFLAG(has_current_point), STRINGIFYFLAG(needs_move_to), STRINGIFYFLAG(has_extents), STRINGIFYFLAG(has_curve_to), STRINGIFYFLAG(stroke_is_rectilinear), STRINGIFYFLAG(fill_is_rectilinear), STRINGIFYFLAG(fill_is_empty), STRINGIFYFLAG(fill_maybe_region) ); #undef STRINGIFYFLAG } _cairo_path_buf_add_op (buf, op); _cairo_path_buf_add_points (buf, points, num_points); return CAIRO_STATUS_SUCCESS; } static void _cairo_path_fixed_add_buf (cairo_path_fixed_t *path, cairo_path_buf_t *buf) { cairo_list_add_tail (&buf->link, &cairo_path_head (path)->link); } COMPILE_TIME_ASSERT (sizeof (cairo_path_op_t) == 1); static cairo_path_buf_t * _cairo_path_buf_create (int size_ops, int size_points) { cairo_path_buf_t *buf; /* adjust size_ops to ensure that buf->points is naturally aligned */ size_ops += sizeof (double) - ((sizeof (cairo_path_buf_t) + size_ops) % sizeof (double)); buf = _cairo_malloc_ab_plus_c (size_points, sizeof (cairo_point_t), size_ops + sizeof (cairo_path_buf_t)); if (buf) { buf->num_ops = 0; buf->num_points = 0; buf->size_ops = size_ops; buf->size_points = size_points; buf->op = (cairo_path_op_t *) (buf + 1); buf->points = (cairo_point_t *) (buf->op + size_ops); } return buf; } static void _cairo_path_buf_destroy (cairo_path_buf_t *buf) { free (buf); } static void _cairo_path_buf_add_op (cairo_path_buf_t *buf, cairo_path_op_t op) { buf->op[buf->num_ops++] = op; } static void _cairo_path_buf_add_points (cairo_path_buf_t *buf, const cairo_point_t *points, int num_points) { if (num_points == 0) return; memcpy (buf->points + buf->num_points, points, sizeof (points[0]) * num_points); buf->num_points += num_points; } cairo_status_t _cairo_path_fixed_interpret (const cairo_path_fixed_t *path, cairo_path_fixed_move_to_func_t *move_to, cairo_path_fixed_line_to_func_t *line_to, cairo_path_fixed_curve_to_func_t *curve_to, cairo_path_fixed_close_path_func_t *close_path, void *closure) { const cairo_path_buf_t *buf; cairo_status_t status; cairo_path_foreach_buf_start (buf, path) { const cairo_point_t *points = buf->points; unsigned int i; for (i = 0; i < buf->num_ops; i++) { switch (buf->op[i]) { case CAIRO_PATH_OP_MOVE_TO: status = (*move_to) (closure, &points[0]); points += 1; break; case CAIRO_PATH_OP_LINE_TO: status = (*line_to) (closure, &points[0]); points += 1; break; case CAIRO_PATH_OP_CURVE_TO: status = (*curve_to) (closure, &points[0], &points[1], &points[2]); points += 3; break; default: ASSERT_NOT_REACHED; case CAIRO_PATH_OP_CLOSE_PATH: status = (*close_path) (closure); break; } if (unlikely (status)) return status; } } cairo_path_foreach_buf_end (buf, path); if (path->needs_move_to && path->has_current_point) return (*move_to) (closure, &path->current_point); return CAIRO_STATUS_SUCCESS; } typedef struct _cairo_path_fixed_append_closure { cairo_point_t offset; cairo_path_fixed_t *path; } cairo_path_fixed_append_closure_t; static cairo_status_t _append_move_to (void *abstract_closure, const cairo_point_t *point) { cairo_path_fixed_append_closure_t *closure = abstract_closure; return _cairo_path_fixed_move_to (closure->path, point->x + closure->offset.x, point->y + closure->offset.y); } static cairo_status_t _append_line_to (void *abstract_closure, const cairo_point_t *point) { cairo_path_fixed_append_closure_t *closure = abstract_closure; return _cairo_path_fixed_line_to (closure->path, point->x + closure->offset.x, point->y + closure->offset.y); } static cairo_status_t _append_curve_to (void *abstract_closure, const cairo_point_t *p0, const cairo_point_t *p1, const cairo_point_t *p2) { cairo_path_fixed_append_closure_t *closure = abstract_closure; return _cairo_path_fixed_curve_to (closure->path, p0->x + closure->offset.x, p0->y + closure->offset.y, p1->x + closure->offset.x, p1->y + closure->offset.y, p2->x + closure->offset.x, p2->y + closure->offset.y); } static cairo_status_t _append_close_path (void *abstract_closure) { cairo_path_fixed_append_closure_t *closure = abstract_closure; return _cairo_path_fixed_close_path (closure->path); } cairo_status_t _cairo_path_fixed_append (cairo_path_fixed_t *path, const cairo_path_fixed_t *other, cairo_fixed_t tx, cairo_fixed_t ty) { cairo_path_fixed_append_closure_t closure; closure.path = path; closure.offset.x = tx; closure.offset.y = ty; return _cairo_path_fixed_interpret (other, _append_move_to, _append_line_to, _append_curve_to, _append_close_path, &closure); } static void _cairo_path_fixed_offset_and_scale (cairo_path_fixed_t *path, cairo_fixed_t offx, cairo_fixed_t offy, cairo_fixed_t scalex, cairo_fixed_t scaley) { cairo_path_buf_t *buf; unsigned int i; if (scalex == CAIRO_FIXED_ONE && scaley == CAIRO_FIXED_ONE) { _cairo_path_fixed_translate (path, offx, offy); return; } path->last_move_point.x = _cairo_fixed_mul (scalex, path->last_move_point.x) + offx; path->last_move_point.y = _cairo_fixed_mul (scaley, path->last_move_point.y) + offy; path->current_point.x = _cairo_fixed_mul (scalex, path->current_point.x) + offx; path->current_point.y = _cairo_fixed_mul (scaley, path->current_point.y) + offy; path->fill_maybe_region = TRUE; cairo_path_foreach_buf_start (buf, path) { for (i = 0; i < buf->num_points; i++) { if (scalex != CAIRO_FIXED_ONE) buf->points[i].x = _cairo_fixed_mul (buf->points[i].x, scalex); buf->points[i].x += offx; if (scaley != CAIRO_FIXED_ONE) buf->points[i].y = _cairo_fixed_mul (buf->points[i].y, scaley); buf->points[i].y += offy; if (path->fill_maybe_region) { path->fill_maybe_region = _cairo_fixed_is_integer (buf->points[i].x) && _cairo_fixed_is_integer (buf->points[i].y); } } } cairo_path_foreach_buf_end (buf, path); path->fill_maybe_region &= path->fill_is_rectilinear; path->extents.p1.x = _cairo_fixed_mul (scalex, path->extents.p1.x) + offx; path->extents.p2.x = _cairo_fixed_mul (scalex, path->extents.p2.x) + offx; if (scalex < 0) { cairo_fixed_t t = path->extents.p1.x; path->extents.p1.x = path->extents.p2.x; path->extents.p2.x = t; } path->extents.p1.y = _cairo_fixed_mul (scaley, path->extents.p1.y) + offy; path->extents.p2.y = _cairo_fixed_mul (scaley, path->extents.p2.y) + offy; if (scaley < 0) { cairo_fixed_t t = path->extents.p1.y; path->extents.p1.y = path->extents.p2.y; path->extents.p2.y = t; } } void _cairo_path_fixed_translate (cairo_path_fixed_t *path, cairo_fixed_t offx, cairo_fixed_t offy) { cairo_path_buf_t *buf; unsigned int i; if (offx == 0 && offy == 0) return; path->last_move_point.x += offx; path->last_move_point.y += offy; path->current_point.x += offx; path->current_point.y += offy; path->fill_maybe_region = TRUE; cairo_path_foreach_buf_start (buf, path) { for (i = 0; i < buf->num_points; i++) { buf->points[i].x += offx; buf->points[i].y += offy; if (path->fill_maybe_region) { path->fill_maybe_region = _cairo_fixed_is_integer (buf->points[i].x) && _cairo_fixed_is_integer (buf->points[i].y); } } } cairo_path_foreach_buf_end (buf, path); path->fill_maybe_region &= path->fill_is_rectilinear; path->extents.p1.x += offx; path->extents.p1.y += offy; path->extents.p2.x += offx; path->extents.p2.y += offy; } static inline void _cairo_path_fixed_transform_point (cairo_point_t *p, const cairo_matrix_t *matrix) { double dx, dy; dx = _cairo_fixed_to_double (p->x); dy = _cairo_fixed_to_double (p->y); cairo_matrix_transform_point (matrix, &dx, &dy); p->x = _cairo_fixed_from_double (dx); p->y = _cairo_fixed_from_double (dy); } /** * _cairo_path_fixed_transform: * @path: a #cairo_path_fixed_t to be transformed * @matrix: a #cairo_matrix_t * * Transform the fixed-point path according to the given matrix. * There is a fast path for the case where @matrix has no rotation * or shear. **/ void _cairo_path_fixed_transform (cairo_path_fixed_t *path, const cairo_matrix_t *matrix) { cairo_box_t extents; cairo_point_t point; cairo_path_buf_t *buf; unsigned int i; if (matrix->yx == 0.0 && matrix->xy == 0.0) { /* Fast path for the common case of scale+transform */ _cairo_path_fixed_offset_and_scale (path, _cairo_fixed_from_double (matrix->x0), _cairo_fixed_from_double (matrix->y0), _cairo_fixed_from_double (matrix->xx), _cairo_fixed_from_double (matrix->yy)); return; } _cairo_path_fixed_transform_point (&path->last_move_point, matrix); _cairo_path_fixed_transform_point (&path->current_point, matrix); buf = cairo_path_head (path); if (buf->num_points == 0) return; extents = path->extents; point = buf->points[0]; _cairo_path_fixed_transform_point (&point, matrix); _cairo_box_set (&path->extents, &point, &point); cairo_path_foreach_buf_start (buf, path) { for (i = 0; i < buf->num_points; i++) { _cairo_path_fixed_transform_point (&buf->points[i], matrix); _cairo_box_add_point (&path->extents, &buf->points[i]); } } cairo_path_foreach_buf_end (buf, path); if (path->has_curve_to) { cairo_bool_t is_tight; _cairo_matrix_transform_bounding_box_fixed (matrix, &extents, &is_tight); if (!is_tight) { cairo_bool_t has_extents; has_extents = _cairo_path_bounder_extents (path, &extents); assert (has_extents); } path->extents = extents; } /* flags might become more strict than needed */ path->stroke_is_rectilinear = FALSE; path->fill_is_rectilinear = FALSE; path->fill_is_empty = FALSE; path->fill_maybe_region = FALSE; } /* Closure for path flattening */ typedef struct cairo_path_flattener { double tolerance; cairo_point_t current_point; cairo_path_fixed_move_to_func_t *move_to; cairo_path_fixed_line_to_func_t *line_to; cairo_path_fixed_close_path_func_t *close_path; void *closure; } cpf_t; static cairo_status_t _cpf_move_to (void *closure, const cairo_point_t *point) { cpf_t *cpf = closure; cpf->current_point = *point; return cpf->move_to (cpf->closure, point); } static cairo_status_t _cpf_line_to (void *closure, const cairo_point_t *point) { cpf_t *cpf = closure; cpf->current_point = *point; return cpf->line_to (cpf->closure, point); } static cairo_status_t _cpf_curve_to (void *closure, const cairo_point_t *p1, const cairo_point_t *p2, const cairo_point_t *p3) { cpf_t *cpf = closure; cairo_spline_t spline; cairo_point_t *p0 = &cpf->current_point; if (! _cairo_spline_init (&spline, (cairo_spline_add_point_func_t)cpf->line_to, cpf->closure, p0, p1, p2, p3)) { return _cpf_line_to (closure, p3); } cpf->current_point = *p3; return _cairo_spline_decompose (&spline, cpf->tolerance); } static cairo_status_t _cpf_close_path (void *closure) { cpf_t *cpf = closure; return cpf->close_path (cpf->closure); } cairo_status_t _cairo_path_fixed_interpret_flat (const cairo_path_fixed_t *path, cairo_path_fixed_move_to_func_t *move_to, cairo_path_fixed_line_to_func_t *line_to, cairo_path_fixed_close_path_func_t *close_path, void *closure, double tolerance) { cpf_t flattener; if (! path->has_curve_to) { return _cairo_path_fixed_interpret (path, move_to, line_to, NULL, close_path, closure); } flattener.tolerance = tolerance; flattener.move_to = move_to; flattener.line_to = line_to; flattener.close_path = close_path; flattener.closure = closure; return _cairo_path_fixed_interpret (path, _cpf_move_to, _cpf_line_to, _cpf_curve_to, _cpf_close_path, &flattener); } static inline void _canonical_box (cairo_box_t *box, const cairo_point_t *p1, const cairo_point_t *p2) { if (p1->x <= p2->x) { box->p1.x = p1->x; box->p2.x = p2->x; } else { box->p1.x = p2->x; box->p2.x = p1->x; } if (p1->y <= p2->y) { box->p1.y = p1->y; box->p2.y = p2->y; } else { box->p1.y = p2->y; box->p2.y = p1->y; } } static inline cairo_bool_t _path_is_quad (const cairo_path_fixed_t *path) { const cairo_path_buf_t *buf = cairo_path_head (path); /* Do we have the right number of ops? */ if (buf->num_ops < 4 || buf->num_ops > 6) return FALSE; /* Check whether the ops are those that would be used for a rectangle */ if (buf->op[0] != CAIRO_PATH_OP_MOVE_TO || buf->op[1] != CAIRO_PATH_OP_LINE_TO || buf->op[2] != CAIRO_PATH_OP_LINE_TO || buf->op[3] != CAIRO_PATH_OP_LINE_TO) { return FALSE; } /* we accept an implicit close for filled paths */ if (buf->num_ops > 4) { /* Now, there are choices. The rectangle might end with a LINE_TO * (to the original point), but this isn't required. If it * doesn't, then it must end with a CLOSE_PATH. */ if (buf->op[4] == CAIRO_PATH_OP_LINE_TO) { if (buf->points[4].x != buf->points[0].x || buf->points[4].y != buf->points[0].y) return FALSE; } else if (buf->op[4] != CAIRO_PATH_OP_CLOSE_PATH) { return FALSE; } if (buf->num_ops == 6) { /* A trailing CLOSE_PATH or MOVE_TO is ok */ if (buf->op[5] != CAIRO_PATH_OP_MOVE_TO && buf->op[5] != CAIRO_PATH_OP_CLOSE_PATH) return FALSE; } } return TRUE; } static inline cairo_bool_t _points_form_rect (const cairo_point_t *points) { if (points[0].y == points[1].y && points[1].x == points[2].x && points[2].y == points[3].y && points[3].x == points[0].x) return TRUE; if (points[0].x == points[1].x && points[1].y == points[2].y && points[2].x == points[3].x && points[3].y == points[0].y) return TRUE; return FALSE; } /* * Check whether the given path contains a single rectangle. */ cairo_bool_t _cairo_path_fixed_is_box (const cairo_path_fixed_t *path, cairo_box_t *box) { const cairo_path_buf_t *buf; if (! path->fill_is_rectilinear) return FALSE; if (! _path_is_quad (path)) return FALSE; buf = cairo_path_head (path); if (_points_form_rect (buf->points)) { _canonical_box (box, &buf->points[0], &buf->points[2]); return TRUE; } return FALSE; } /* Determine whether two lines A->B and C->D intersect based on the * algorithm described here: http://paulbourke.net/geometry/pointlineplane/ */ static inline cairo_bool_t _lines_intersect_or_are_coincident (cairo_point_t a, cairo_point_t b, cairo_point_t c, cairo_point_t d) { cairo_int64_t numerator_a, numerator_b, denominator; cairo_bool_t denominator_negative; denominator = _cairo_int64_sub (_cairo_int32x32_64_mul (d.y - c.y, b.x - a.x), _cairo_int32x32_64_mul (d.x - c.x, b.y - a.y)); numerator_a = _cairo_int64_sub (_cairo_int32x32_64_mul (d.x - c.x, a.y - c.y), _cairo_int32x32_64_mul (d.y - c.y, a.x - c.x)); numerator_b = _cairo_int64_sub (_cairo_int32x32_64_mul (b.x - a.x, a.y - c.y), _cairo_int32x32_64_mul (b.y - a.y, a.x - c.x)); if (_cairo_int64_is_zero (denominator)) { /* If the denominator and numerators are both zero, * the lines are coincident. */ if (_cairo_int64_is_zero (numerator_a) && _cairo_int64_is_zero (numerator_b)) return TRUE; /* Otherwise, a zero denominator indicates the lines are * parallel and never intersect. */ return FALSE; } /* The lines intersect if both quotients are between 0 and 1 (exclusive). */ /* We first test whether either quotient is a negative number. */ denominator_negative = _cairo_int64_negative (denominator); if (_cairo_int64_negative (numerator_a) ^ denominator_negative) return FALSE; if (_cairo_int64_negative (numerator_b) ^ denominator_negative) return FALSE; /* A zero quotient indicates an "intersection" at an endpoint, which * we aren't considering a true intersection. */ if (_cairo_int64_is_zero (numerator_a) || _cairo_int64_is_zero (numerator_b)) return FALSE; /* If the absolute value of the numerator is larger than or equal to the * denominator the result of the division would be greater than or equal * to one. */ if (! denominator_negative) { if (! _cairo_int64_lt (numerator_a, denominator) || ! _cairo_int64_lt (numerator_b, denominator)) return FALSE; } else { if (! _cairo_int64_lt (denominator, numerator_a) || ! _cairo_int64_lt (denominator, numerator_b)) return FALSE; } return TRUE; } cairo_bool_t _cairo_path_fixed_is_simple_quad (const cairo_path_fixed_t *path) { const cairo_point_t *points; if (! _path_is_quad (path)) return FALSE; points = cairo_path_head (path)->points; if (_points_form_rect (points)) return TRUE; if (_lines_intersect_or_are_coincident (points[0], points[1], points[3], points[2])) return FALSE; if (_lines_intersect_or_are_coincident (points[0], points[3], points[1], points[2])) return FALSE; return TRUE; } cairo_bool_t _cairo_path_fixed_is_stroke_box (const cairo_path_fixed_t *path, cairo_box_t *box) { const cairo_path_buf_t *buf = cairo_path_head (path); if (! path->fill_is_rectilinear) return FALSE; /* Do we have the right number of ops? */ if (buf->num_ops != 5) return FALSE; /* Check whether the ops are those that would be used for a rectangle */ if (buf->op[0] != CAIRO_PATH_OP_MOVE_TO || buf->op[1] != CAIRO_PATH_OP_LINE_TO || buf->op[2] != CAIRO_PATH_OP_LINE_TO || buf->op[3] != CAIRO_PATH_OP_LINE_TO || buf->op[4] != CAIRO_PATH_OP_CLOSE_PATH) { return FALSE; } /* Ok, we may have a box, if the points line up */ if (buf->points[0].y == buf->points[1].y && buf->points[1].x == buf->points[2].x && buf->points[2].y == buf->points[3].y && buf->points[3].x == buf->points[0].x) { _canonical_box (box, &buf->points[0], &buf->points[2]); return TRUE; } if (buf->points[0].x == buf->points[1].x && buf->points[1].y == buf->points[2].y && buf->points[2].x == buf->points[3].x && buf->points[3].y == buf->points[0].y) { _canonical_box (box, &buf->points[0], &buf->points[2]); return TRUE; } return FALSE; } /* * Check whether the given path contains a single rectangle * that is logically equivalent to: * * cairo_move_to (cr, x, y); * cairo_rel_line_to (cr, width, 0); * cairo_rel_line_to (cr, 0, height); * cairo_rel_line_to (cr, -width, 0); * cairo_close_path (cr); * */ cairo_bool_t _cairo_path_fixed_is_rectangle (const cairo_path_fixed_t *path, cairo_box_t *box) { const cairo_path_buf_t *buf; if (! _cairo_path_fixed_is_box (path, box)) return FALSE; /* This check is valid because the current implementation of * _cairo_path_fixed_is_box () only accepts rectangles like: * move,line,line,line[,line|close[,close|move]]. */ buf = cairo_path_head (path); if (buf->num_ops > 4) return TRUE; return FALSE; } void _cairo_path_fixed_iter_init (cairo_path_fixed_iter_t *iter, const cairo_path_fixed_t *path) { iter->first = iter->buf = cairo_path_head (path); iter->n_op = 0; iter->n_point = 0; } static cairo_bool_t _cairo_path_fixed_iter_next_op (cairo_path_fixed_iter_t *iter) { if (++iter->n_op >= iter->buf->num_ops) { iter->buf = cairo_path_buf_next (iter->buf); if (iter->buf == iter->first) { iter->buf = NULL; return FALSE; } iter->n_op = 0; iter->n_point = 0; } return TRUE; } cairo_bool_t _cairo_path_fixed_iter_is_fill_box (cairo_path_fixed_iter_t *_iter, cairo_box_t *box) { cairo_point_t points[5]; cairo_path_fixed_iter_t iter; if (_iter->buf == NULL) return FALSE; iter = *_iter; if (iter.n_op == iter.buf->num_ops && ! _cairo_path_fixed_iter_next_op (&iter)) return FALSE; /* Check whether the ops are those that would be used for a rectangle */ if (iter.buf->op[iter.n_op] != CAIRO_PATH_OP_MOVE_TO) return FALSE; points[0] = iter.buf->points[iter.n_point++]; if (! _cairo_path_fixed_iter_next_op (&iter)) return FALSE; if (iter.buf->op[iter.n_op] != CAIRO_PATH_OP_LINE_TO) return FALSE; points[1] = iter.buf->points[iter.n_point++]; if (! _cairo_path_fixed_iter_next_op (&iter)) return FALSE; /* a horizontal/vertical closed line is also a degenerate rectangle */ switch (iter.buf->op[iter.n_op]) { case CAIRO_PATH_OP_CLOSE_PATH: _cairo_path_fixed_iter_next_op (&iter); case CAIRO_PATH_OP_MOVE_TO: /* implicit close */ box->p1 = box->p2 = points[0]; *_iter = iter; return TRUE; default: return FALSE; case CAIRO_PATH_OP_LINE_TO: break; } points[2] = iter.buf->points[iter.n_point++]; if (! _cairo_path_fixed_iter_next_op (&iter)) return FALSE; if (iter.buf->op[iter.n_op] != CAIRO_PATH_OP_LINE_TO) return FALSE; points[3] = iter.buf->points[iter.n_point++]; /* Now, there are choices. The rectangle might end with a LINE_TO * (to the original point), but this isn't required. If it * doesn't, then it must end with a CLOSE_PATH (which may be implicit). */ if (! _cairo_path_fixed_iter_next_op (&iter)) { /* implicit close due to fill */ } else if (iter.buf->op[iter.n_op] == CAIRO_PATH_OP_LINE_TO) { points[4] = iter.buf->points[iter.n_point++]; if (points[4].x != points[0].x || points[4].y != points[0].y) return FALSE; _cairo_path_fixed_iter_next_op (&iter); } else if (iter.buf->op[iter.n_op] == CAIRO_PATH_OP_CLOSE_PATH) { _cairo_path_fixed_iter_next_op (&iter); } else if (iter.buf->op[iter.n_op] == CAIRO_PATH_OP_MOVE_TO) { /* implicit close-path due to new-sub-path */ } else { return FALSE; } /* Ok, we may have a box, if the points line up */ if (points[0].y == points[1].y && points[1].x == points[2].x && points[2].y == points[3].y && points[3].x == points[0].x) { box->p1 = points[0]; box->p2 = points[2]; *_iter = iter; return TRUE; } if (points[0].x == points[1].x && points[1].y == points[2].y && points[2].x == points[3].x && points[3].y == points[0].y) { box->p1 = points[1]; box->p2 = points[3]; *_iter = iter; return TRUE; } return FALSE; } cairo_bool_t _cairo_path_fixed_iter_at_end (const cairo_path_fixed_iter_t *iter) { if (iter->buf == NULL) return TRUE; return iter->n_op == iter->buf->num_ops; }