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diff --git a/Build/source/libs/cairo/cairo-src/src/cairo-path-stroke.c b/Build/source/libs/cairo/cairo-src/src/cairo-path-stroke.c
deleted file mode 100644
index 64cec8f272e..00000000000
--- a/Build/source/libs/cairo/cairo-src/src/cairo-path-stroke.c
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-/* -*- 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
- *
- * 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 <cworth@cworth.org>
- * Chris Wilson <chris@chris-wilson.co.uk>
- */
-
-#define _DEFAULT_SOURCE /* for hypot() */
-#include "cairoint.h"
-
-#include "cairo-box-inline.h"
-#include "cairo-boxes-private.h"
-#include "cairo-error-private.h"
-#include "cairo-path-fixed-private.h"
-#include "cairo-slope-private.h"
-#include "cairo-stroke-dash-private.h"
-#include "cairo-traps-private.h"
-
-typedef struct cairo_stroker {
- cairo_stroke_style_t style;
-
- const cairo_matrix_t *ctm;
- const cairo_matrix_t *ctm_inverse;
- double half_line_width;
- double tolerance;
- double spline_cusp_tolerance;
- double ctm_determinant;
- cairo_bool_t ctm_det_positive;
-
- void *closure;
- cairo_status_t (*add_external_edge) (void *closure,
- const cairo_point_t *p1,
- const cairo_point_t *p2);
- cairo_status_t (*add_triangle) (void *closure,
- const cairo_point_t triangle[3]);
- cairo_status_t (*add_triangle_fan) (void *closure,
- const cairo_point_t *midpt,
- const cairo_point_t *points,
- int npoints);
- cairo_status_t (*add_convex_quad) (void *closure,
- const cairo_point_t quad[4]);
-
- cairo_pen_t pen;
-
- cairo_point_t current_point;
- cairo_point_t first_point;
-
- cairo_bool_t has_initial_sub_path;
-
- cairo_bool_t has_current_face;
- cairo_stroke_face_t current_face;
-
- cairo_bool_t has_first_face;
- cairo_stroke_face_t first_face;
-
- cairo_stroker_dash_t dash;
-
- cairo_bool_t has_bounds;
- cairo_box_t bounds;
-} cairo_stroker_t;
-
-static void
-_cairo_stroker_limit (cairo_stroker_t *stroker,
- const cairo_path_fixed_t *path,
- const cairo_box_t *boxes,
- int num_boxes)
-{
- double dx, dy;
- cairo_fixed_t fdx, fdy;
-
- stroker->has_bounds = TRUE;
- _cairo_boxes_get_extents (boxes, num_boxes, &stroker->bounds);
-
- /* Extend the bounds in each direction to account for the maximum area
- * we might generate trapezoids, to capture line segments that are outside
- * of the bounds but which might generate rendering that's within bounds.
- */
-
- _cairo_stroke_style_max_distance_from_path (&stroker->style, path,
- stroker->ctm, &dx, &dy);
-
- fdx = _cairo_fixed_from_double (dx);
- fdy = _cairo_fixed_from_double (dy);
-
- stroker->bounds.p1.x -= fdx;
- stroker->bounds.p2.x += fdx;
-
- stroker->bounds.p1.y -= fdy;
- stroker->bounds.p2.y += fdy;
-}
-
-static cairo_status_t
-_cairo_stroker_init (cairo_stroker_t *stroker,
- const cairo_path_fixed_t *path,
- const cairo_stroke_style_t *stroke_style,
- const cairo_matrix_t *ctm,
- const cairo_matrix_t *ctm_inverse,
- double tolerance,
- const cairo_box_t *limits,
- int num_limits)
-{
- cairo_status_t status;
-
- stroker->style = *stroke_style;
- stroker->ctm = ctm;
- stroker->ctm_inverse = ctm_inverse;
- stroker->tolerance = tolerance;
- stroker->half_line_width = stroke_style->line_width / 2.0;
-
- /* To test whether we need to join two segments of a spline using
- * a round-join or a bevel-join, we can inspect the angle between the
- * two segments. If the difference between the chord distance
- * (half-line-width times the cosine of the bisection angle) and the
- * half-line-width itself is greater than tolerance then we need to
- * inject a point.
- */
- stroker->spline_cusp_tolerance = 1 - tolerance / stroker->half_line_width;
- stroker->spline_cusp_tolerance *= stroker->spline_cusp_tolerance;
- stroker->spline_cusp_tolerance *= 2;
- stroker->spline_cusp_tolerance -= 1;
-
- stroker->ctm_determinant = _cairo_matrix_compute_determinant (stroker->ctm);
- stroker->ctm_det_positive = stroker->ctm_determinant >= 0.0;
-
- status = _cairo_pen_init (&stroker->pen,
- stroker->half_line_width, tolerance, ctm);
- if (unlikely (status))
- return status;
-
- stroker->has_current_face = FALSE;
- stroker->has_first_face = FALSE;
- stroker->has_initial_sub_path = FALSE;
-
- _cairo_stroker_dash_init (&stroker->dash, stroke_style);
-
- stroker->add_external_edge = NULL;
-
- stroker->has_bounds = FALSE;
- if (num_limits)
- _cairo_stroker_limit (stroker, path, limits, num_limits);
-
- return CAIRO_STATUS_SUCCESS;
-}
-
-static void
-_cairo_stroker_fini (cairo_stroker_t *stroker)
-{
- _cairo_pen_fini (&stroker->pen);
-}
-
-static void
-_translate_point (cairo_point_t *point, const cairo_point_t *offset)
-{
- point->x += offset->x;
- point->y += offset->y;
-}
-
-static int
-_cairo_stroker_join_is_clockwise (const cairo_stroke_face_t *in,
- const cairo_stroke_face_t *out)
-{
- cairo_slope_t in_slope, out_slope;
-
- _cairo_slope_init (&in_slope, &in->point, &in->cw);
- _cairo_slope_init (&out_slope, &out->point, &out->cw);
-
- return _cairo_slope_compare (&in_slope, &out_slope) < 0;
-}
-
-/**
- * _cairo_slope_compare_sgn:
- *
- * Return -1, 0 or 1 depending on the relative slopes of
- * two lines.
- **/
-static int
-_cairo_slope_compare_sgn (double dx1, double dy1, double dx2, double dy2)
-{
- double c = (dx1 * dy2 - dx2 * dy1);
-
- if (c > 0) return 1;
- if (c < 0) return -1;
- return 0;
-}
-
-static inline int
-_range_step (int i, int step, int max)
-{
- i += step;
- if (i < 0)
- i = max - 1;
- if (i >= max)
- i = 0;
- return i;
-}
-
-/*
- * Construct a fan around the midpoint using the vertices from pen between
- * inpt and outpt.
- */
-static cairo_status_t
-_tessellate_fan (cairo_stroker_t *stroker,
- const cairo_slope_t *in_vector,
- const cairo_slope_t *out_vector,
- const cairo_point_t *midpt,
- const cairo_point_t *inpt,
- const cairo_point_t *outpt,
- cairo_bool_t clockwise)
-{
- cairo_point_t stack_points[64], *points = stack_points;
- cairo_pen_t *pen = &stroker->pen;
- int start, stop, num_points = 0;
- cairo_status_t status;
-
- if (stroker->has_bounds &&
- ! _cairo_box_contains_point (&stroker->bounds, midpt))
- goto BEVEL;
-
- assert (stroker->pen.num_vertices);
-
- if (clockwise) {
- _cairo_pen_find_active_ccw_vertices (pen,
- in_vector, out_vector,
- &start, &stop);
- if (stroker->add_external_edge) {
- cairo_point_t last;
- last = *inpt;
- while (start != stop) {
- cairo_point_t p = *midpt;
- _translate_point (&p, &pen->vertices[start].point);
-
- status = stroker->add_external_edge (stroker->closure,
- &last, &p);
- if (unlikely (status))
- return status;
- last = p;
-
- if (start-- == 0)
- start += pen->num_vertices;
- }
- status = stroker->add_external_edge (stroker->closure,
- &last, outpt);
- } else {
- if (start == stop)
- goto BEVEL;
-
- num_points = stop - start;
- if (num_points < 0)
- num_points += pen->num_vertices;
- num_points += 2;
- if (num_points > ARRAY_LENGTH(stack_points)) {
- points = _cairo_malloc_ab (num_points, sizeof (cairo_point_t));
- if (unlikely (points == NULL))
- return _cairo_error (CAIRO_STATUS_NO_MEMORY);
- }
-
- points[0] = *inpt;
- num_points = 1;
- while (start != stop) {
- points[num_points] = *midpt;
- _translate_point (&points[num_points], &pen->vertices[start].point);
- num_points++;
-
- if (start-- == 0)
- start += pen->num_vertices;
- }
- points[num_points++] = *outpt;
- }
- } else {
- _cairo_pen_find_active_cw_vertices (pen,
- in_vector, out_vector,
- &start, &stop);
- if (stroker->add_external_edge) {
- cairo_point_t last;
- last = *inpt;
- while (start != stop) {
- cairo_point_t p = *midpt;
- _translate_point (&p, &pen->vertices[start].point);
-
- status = stroker->add_external_edge (stroker->closure,
- &p, &last);
- if (unlikely (status))
- return status;
- last = p;
-
- if (++start == pen->num_vertices)
- start = 0;
- }
- status = stroker->add_external_edge (stroker->closure,
- outpt, &last);
- } else {
- if (start == stop)
- goto BEVEL;
-
- num_points = stop - start;
- if (num_points < 0)
- num_points += pen->num_vertices;
- num_points += 2;
- if (num_points > ARRAY_LENGTH(stack_points)) {
- points = _cairo_malloc_ab (num_points, sizeof (cairo_point_t));
- if (unlikely (points == NULL))
- return _cairo_error (CAIRO_STATUS_NO_MEMORY);
- }
-
- points[0] = *inpt;
- num_points = 1;
- while (start != stop) {
- points[num_points] = *midpt;
- _translate_point (&points[num_points], &pen->vertices[start].point);
- num_points++;
-
- if (++start == pen->num_vertices)
- start = 0;
- }
- points[num_points++] = *outpt;
- }
- }
-
- if (num_points) {
- status = stroker->add_triangle_fan (stroker->closure,
- midpt, points, num_points);
- }
-
- if (points != stack_points)
- free (points);
-
- return status;
-
-BEVEL:
- /* Ensure a leak free connection... */
- if (stroker->add_external_edge != NULL) {
- if (clockwise)
- return stroker->add_external_edge (stroker->closure, inpt, outpt);
- else
- return stroker->add_external_edge (stroker->closure, outpt, inpt);
- } else {
- stack_points[0] = *midpt;
- stack_points[1] = *inpt;
- stack_points[2] = *outpt;
- return stroker->add_triangle (stroker->closure, stack_points);
- }
-}
-
-static cairo_status_t
-_cairo_stroker_join (cairo_stroker_t *stroker,
- const cairo_stroke_face_t *in,
- const cairo_stroke_face_t *out)
-{
- int clockwise = _cairo_stroker_join_is_clockwise (out, in);
- const cairo_point_t *inpt, *outpt;
- cairo_point_t points[4];
- cairo_status_t status;
-
- if (in->cw.x == out->cw.x && in->cw.y == out->cw.y &&
- in->ccw.x == out->ccw.x && in->ccw.y == out->ccw.y)
- {
- return CAIRO_STATUS_SUCCESS;
- }
-
- if (clockwise) {
- if (stroker->add_external_edge != NULL) {
- status = stroker->add_external_edge (stroker->closure,
- &out->cw, &in->point);
- if (unlikely (status))
- return status;
-
- status = stroker->add_external_edge (stroker->closure,
- &in->point, &in->cw);
- if (unlikely (status))
- return status;
- }
-
- inpt = &in->ccw;
- outpt = &out->ccw;
- } else {
- if (stroker->add_external_edge != NULL) {
- status = stroker->add_external_edge (stroker->closure,
- &in->ccw, &in->point);
- if (unlikely (status))
- return status;
-
- status = stroker->add_external_edge (stroker->closure,
- &in->point, &out->ccw);
- if (unlikely (status))
- return status;
- }
-
- inpt = &in->cw;
- outpt = &out->cw;
- }
-
- switch (stroker->style.line_join) {
- case CAIRO_LINE_JOIN_ROUND:
- /* construct a fan around the common midpoint */
- return _tessellate_fan (stroker,
- &in->dev_vector,
- &out->dev_vector,
- &in->point, inpt, outpt,
- clockwise);
-
- case CAIRO_LINE_JOIN_MITER:
- default: {
- /* dot product of incoming slope vector with outgoing slope vector */
- double in_dot_out = -in->usr_vector.x * out->usr_vector.x +
- -in->usr_vector.y * out->usr_vector.y;
- double ml = stroker->style.miter_limit;
-
- /* Check the miter limit -- lines meeting at an acute angle
- * can generate long miters, the limit converts them to bevel
- *
- * Consider the miter join formed when two line segments
- * meet at an angle psi:
- *
- * /.\
- * /. .\
- * /./ \.\
- * /./psi\.\
- *
- * We can zoom in on the right half of that to see:
- *
- * |\
- * | \ psi/2
- * | \
- * | \
- * | \
- * | \
- * miter \
- * length \
- * | \
- * | .\
- * | . \
- * |. line \
- * \ width \
- * \ \
- *
- *
- * The right triangle in that figure, (the line-width side is
- * shown faintly with three '.' characters), gives us the
- * following expression relating miter length, angle and line
- * width:
- *
- * 1 /sin (psi/2) = miter_length / line_width
- *
- * The right-hand side of this relationship is the same ratio
- * in which the miter limit (ml) is expressed. We want to know
- * when the miter length is within the miter limit. That is
- * when the following condition holds:
- *
- * 1/sin(psi/2) <= ml
- * 1 <= ml sin(psi/2)
- * 1 <= ml² sin²(psi/2)
- * 2 <= ml² 2 sin²(psi/2)
- * 2·sin²(psi/2) = 1-cos(psi)
- * 2 <= ml² (1-cos(psi))
- *
- * in · out = |in| |out| cos (psi)
- *
- * in and out are both unit vectors, so:
- *
- * in · out = cos (psi)
- *
- * 2 <= ml² (1 - in · out)
- *
- */
- if (2 <= ml * ml * (1 - in_dot_out)) {
- double x1, y1, x2, y2;
- double mx, my;
- double dx1, dx2, dy1, dy2;
- double ix, iy;
- double fdx1, fdy1, fdx2, fdy2;
- double mdx, mdy;
-
- /*
- * we've got the points already transformed to device
- * space, but need to do some computation with them and
- * also need to transform the slope from user space to
- * device space
- */
- /* outer point of incoming line face */
- x1 = _cairo_fixed_to_double (inpt->x);
- y1 = _cairo_fixed_to_double (inpt->y);
- dx1 = in->usr_vector.x;
- dy1 = in->usr_vector.y;
- cairo_matrix_transform_distance (stroker->ctm, &dx1, &dy1);
-
- /* outer point of outgoing line face */
- x2 = _cairo_fixed_to_double (outpt->x);
- y2 = _cairo_fixed_to_double (outpt->y);
- dx2 = out->usr_vector.x;
- dy2 = out->usr_vector.y;
- cairo_matrix_transform_distance (stroker->ctm, &dx2, &dy2);
-
- /*
- * Compute the location of the outer corner of the miter.
- * That's pretty easy -- just the intersection of the two
- * outer edges. We've got slopes and points on each
- * of those edges. Compute my directly, then compute
- * mx by using the edge with the larger dy; that avoids
- * dividing by values close to zero.
- */
- my = (((x2 - x1) * dy1 * dy2 - y2 * dx2 * dy1 + y1 * dx1 * dy2) /
- (dx1 * dy2 - dx2 * dy1));
- if (fabs (dy1) >= fabs (dy2))
- mx = (my - y1) * dx1 / dy1 + x1;
- else
- mx = (my - y2) * dx2 / dy2 + x2;
-
- /*
- * When the two outer edges are nearly parallel, slight
- * perturbations in the position of the outer points of the lines
- * caused by representing them in fixed point form can cause the
- * intersection point of the miter to move a large amount. If
- * that moves the miter intersection from between the two faces,
- * then draw a bevel instead.
- */
-
- ix = _cairo_fixed_to_double (in->point.x);
- iy = _cairo_fixed_to_double (in->point.y);
-
- /* slope of one face */
- fdx1 = x1 - ix; fdy1 = y1 - iy;
-
- /* slope of the other face */
- fdx2 = x2 - ix; fdy2 = y2 - iy;
-
- /* slope from the intersection to the miter point */
- mdx = mx - ix; mdy = my - iy;
-
- /*
- * Make sure the miter point line lies between the two
- * faces by comparing the slopes
- */
- if (_cairo_slope_compare_sgn (fdx1, fdy1, mdx, mdy) !=
- _cairo_slope_compare_sgn (fdx2, fdy2, mdx, mdy))
- {
- if (stroker->add_external_edge != NULL) {
- points[0].x = _cairo_fixed_from_double (mx);
- points[0].y = _cairo_fixed_from_double (my);
-
- if (clockwise) {
- status = stroker->add_external_edge (stroker->closure,
- inpt, &points[0]);
- if (unlikely (status))
- return status;
-
- status = stroker->add_external_edge (stroker->closure,
- &points[0], outpt);
- if (unlikely (status))
- return status;
- } else {
- status = stroker->add_external_edge (stroker->closure,
- outpt, &points[0]);
- if (unlikely (status))
- return status;
-
- status = stroker->add_external_edge (stroker->closure,
- &points[0], inpt);
- if (unlikely (status))
- return status;
- }
-
- return CAIRO_STATUS_SUCCESS;
- } else {
- points[0] = in->point;
- points[1] = *inpt;
- points[2].x = _cairo_fixed_from_double (mx);
- points[2].y = _cairo_fixed_from_double (my);
- points[3] = *outpt;
-
- return stroker->add_convex_quad (stroker->closure, points);
- }
- }
- }
- }
-
- /* fall through ... */
-
- case CAIRO_LINE_JOIN_BEVEL:
- if (stroker->add_external_edge != NULL) {
- if (clockwise) {
- return stroker->add_external_edge (stroker->closure,
- inpt, outpt);
- } else {
- return stroker->add_external_edge (stroker->closure,
- outpt, inpt);
- }
- } else {
- points[0] = in->point;
- points[1] = *inpt;
- points[2] = *outpt;
-
- return stroker->add_triangle (stroker->closure, points);
- }
- }
-}
-
-static cairo_status_t
-_cairo_stroker_add_cap (cairo_stroker_t *stroker,
- const cairo_stroke_face_t *f)
-{
- switch (stroker->style.line_cap) {
- case CAIRO_LINE_CAP_ROUND: {
- cairo_slope_t slope;
-
- slope.dx = -f->dev_vector.dx;
- slope.dy = -f->dev_vector.dy;
-
- return _tessellate_fan (stroker,
- &f->dev_vector,
- &slope,
- &f->point, &f->cw, &f->ccw,
- FALSE);
-
- }
-
- case CAIRO_LINE_CAP_SQUARE: {
- double dx, dy;
- cairo_slope_t fvector;
- cairo_point_t quad[4];
-
- dx = f->usr_vector.x;
- dy = f->usr_vector.y;
- dx *= stroker->half_line_width;
- dy *= stroker->half_line_width;
- cairo_matrix_transform_distance (stroker->ctm, &dx, &dy);
- fvector.dx = _cairo_fixed_from_double (dx);
- fvector.dy = _cairo_fixed_from_double (dy);
-
- quad[0] = f->ccw;
- quad[1].x = f->ccw.x + fvector.dx;
- quad[1].y = f->ccw.y + fvector.dy;
- quad[2].x = f->cw.x + fvector.dx;
- quad[2].y = f->cw.y + fvector.dy;
- quad[3] = f->cw;
-
- if (stroker->add_external_edge != NULL) {
- cairo_status_t status;
-
- status = stroker->add_external_edge (stroker->closure,
- &quad[0], &quad[1]);
- if (unlikely (status))
- return status;
-
- status = stroker->add_external_edge (stroker->closure,
- &quad[1], &quad[2]);
- if (unlikely (status))
- return status;
-
- status = stroker->add_external_edge (stroker->closure,
- &quad[2], &quad[3]);
- if (unlikely (status))
- return status;
-
- return CAIRO_STATUS_SUCCESS;
- } else {
- return stroker->add_convex_quad (stroker->closure, quad);
- }
- }
-
- case CAIRO_LINE_CAP_BUTT:
- default:
- if (stroker->add_external_edge != NULL) {
- return stroker->add_external_edge (stroker->closure,
- &f->ccw, &f->cw);
- } else {
- return CAIRO_STATUS_SUCCESS;
- }
- }
-}
-
-static cairo_status_t
-_cairo_stroker_add_leading_cap (cairo_stroker_t *stroker,
- const cairo_stroke_face_t *face)
-{
- cairo_stroke_face_t reversed;
- cairo_point_t t;
-
- reversed = *face;
-
- /* The initial cap needs an outward facing vector. Reverse everything */
- reversed.usr_vector.x = -reversed.usr_vector.x;
- reversed.usr_vector.y = -reversed.usr_vector.y;
- reversed.dev_vector.dx = -reversed.dev_vector.dx;
- reversed.dev_vector.dy = -reversed.dev_vector.dy;
- t = reversed.cw;
- reversed.cw = reversed.ccw;
- reversed.ccw = t;
-
- return _cairo_stroker_add_cap (stroker, &reversed);
-}
-
-static cairo_status_t
-_cairo_stroker_add_trailing_cap (cairo_stroker_t *stroker,
- const cairo_stroke_face_t *face)
-{
- return _cairo_stroker_add_cap (stroker, face);
-}
-
-static inline cairo_bool_t
-_compute_normalized_device_slope (double *dx, double *dy,
- const cairo_matrix_t *ctm_inverse,
- double *mag_out)
-{
- double dx0 = *dx, dy0 = *dy;
- double mag;
-
- cairo_matrix_transform_distance (ctm_inverse, &dx0, &dy0);
-
- if (dx0 == 0.0 && dy0 == 0.0) {
- if (mag_out)
- *mag_out = 0.0;
- return FALSE;
- }
-
- if (dx0 == 0.0) {
- *dx = 0.0;
- if (dy0 > 0.0) {
- mag = dy0;
- *dy = 1.0;
- } else {
- mag = -dy0;
- *dy = -1.0;
- }
- } else if (dy0 == 0.0) {
- *dy = 0.0;
- if (dx0 > 0.0) {
- mag = dx0;
- *dx = 1.0;
- } else {
- mag = -dx0;
- *dx = -1.0;
- }
- } else {
- mag = hypot (dx0, dy0);
- *dx = dx0 / mag;
- *dy = dy0 / mag;
- }
-
- if (mag_out)
- *mag_out = mag;
-
- return TRUE;
-}
-
-static void
-_compute_face (const cairo_point_t *point,
- const cairo_slope_t *dev_slope,
- double slope_dx,
- double slope_dy,
- cairo_stroker_t *stroker,
- cairo_stroke_face_t *face)
-{
- double face_dx, face_dy;
- cairo_point_t offset_ccw, offset_cw;
-
- /*
- * rotate to get a line_width/2 vector along the face, note that
- * the vector must be rotated the right direction in device space,
- * but by 90° in user space. So, the rotation depends on
- * whether the ctm reflects or not, and that can be determined
- * by looking at the determinant of the matrix.
- */
- if (stroker->ctm_det_positive)
- {
- face_dx = - slope_dy * stroker->half_line_width;
- face_dy = slope_dx * stroker->half_line_width;
- }
- else
- {
- face_dx = slope_dy * stroker->half_line_width;
- face_dy = - slope_dx * stroker->half_line_width;
- }
-
- /* back to device space */
- cairo_matrix_transform_distance (stroker->ctm, &face_dx, &face_dy);
-
- offset_ccw.x = _cairo_fixed_from_double (face_dx);
- offset_ccw.y = _cairo_fixed_from_double (face_dy);
- offset_cw.x = -offset_ccw.x;
- offset_cw.y = -offset_ccw.y;
-
- face->ccw = *point;
- _translate_point (&face->ccw, &offset_ccw);
-
- face->point = *point;
-
- face->cw = *point;
- _translate_point (&face->cw, &offset_cw);
-
- face->usr_vector.x = slope_dx;
- face->usr_vector.y = slope_dy;
-
- face->dev_vector = *dev_slope;
-}
-
-static cairo_status_t
-_cairo_stroker_add_caps (cairo_stroker_t *stroker)
-{
- cairo_status_t status;
-
- /* check for a degenerative sub_path */
- if (stroker->has_initial_sub_path
- && ! stroker->has_first_face
- && ! stroker->has_current_face
- && stroker->style.line_cap == CAIRO_LINE_CAP_ROUND)
- {
- /* pick an arbitrary slope to use */
- double dx = 1.0, dy = 0.0;
- cairo_slope_t slope = { CAIRO_FIXED_ONE, 0 };
- cairo_stroke_face_t face;
-
- _compute_normalized_device_slope (&dx, &dy,
- stroker->ctm_inverse, NULL);
-
- /* arbitrarily choose first_point
- * first_point and current_point should be the same */
- _compute_face (&stroker->first_point, &slope, dx, dy, stroker, &face);
-
- status = _cairo_stroker_add_leading_cap (stroker, &face);
- if (unlikely (status))
- return status;
-
- status = _cairo_stroker_add_trailing_cap (stroker, &face);
- if (unlikely (status))
- return status;
- }
-
- if (stroker->has_first_face) {
- status = _cairo_stroker_add_leading_cap (stroker,
- &stroker->first_face);
- if (unlikely (status))
- return status;
- }
-
- if (stroker->has_current_face) {
- status = _cairo_stroker_add_trailing_cap (stroker,
- &stroker->current_face);
- if (unlikely (status))
- return status;
- }
-
- return CAIRO_STATUS_SUCCESS;
-}
-
-static cairo_status_t
-_cairo_stroker_add_sub_edge (cairo_stroker_t *stroker,
- const cairo_point_t *p1,
- const cairo_point_t *p2,
- cairo_slope_t *dev_slope,
- double slope_dx, double slope_dy,
- cairo_stroke_face_t *start,
- cairo_stroke_face_t *end)
-{
- _compute_face (p1, dev_slope, slope_dx, slope_dy, stroker, start);
- *end = *start;
-
- if (p1->x == p2->x && p1->y == p2->y)
- return CAIRO_STATUS_SUCCESS;
-
- end->point = *p2;
- end->ccw.x += p2->x - p1->x;
- end->ccw.y += p2->y - p1->y;
- end->cw.x += p2->x - p1->x;
- end->cw.y += p2->y - p1->y;
-
- if (stroker->add_external_edge != NULL) {
- cairo_status_t status;
-
- status = stroker->add_external_edge (stroker->closure,
- &end->cw, &start->cw);
- if (unlikely (status))
- return status;
-
- status = stroker->add_external_edge (stroker->closure,
- &start->ccw, &end->ccw);
- if (unlikely (status))
- return status;
-
- return CAIRO_STATUS_SUCCESS;
- } else {
- cairo_point_t quad[4];
-
- quad[0] = start->cw;
- quad[1] = end->cw;
- quad[2] = end->ccw;
- quad[3] = start->ccw;
-
- return stroker->add_convex_quad (stroker->closure, quad);
- }
-}
-
-static cairo_status_t
-_cairo_stroker_move_to (void *closure,
- const cairo_point_t *point)
-{
- cairo_stroker_t *stroker = closure;
- cairo_status_t status;
-
- /* reset the dash pattern for new sub paths */
- _cairo_stroker_dash_start (&stroker->dash);
-
- /* Cap the start and end of the previous sub path as needed */
- status = _cairo_stroker_add_caps (stroker);
- if (unlikely (status))
- return status;
-
- stroker->first_point = *point;
- stroker->current_point = *point;
-
- stroker->has_first_face = FALSE;
- stroker->has_current_face = FALSE;
- stroker->has_initial_sub_path = FALSE;
-
- return CAIRO_STATUS_SUCCESS;
-}
-
-static cairo_status_t
-_cairo_stroker_line_to (void *closure,
- const cairo_point_t *point)
-{
- cairo_stroker_t *stroker = closure;
- cairo_stroke_face_t start, end;
- cairo_point_t *p1 = &stroker->current_point;
- cairo_slope_t dev_slope;
- double slope_dx, slope_dy;
- cairo_status_t status;
-
- stroker->has_initial_sub_path = TRUE;
-
- if (p1->x == point->x && p1->y == point->y)
- return CAIRO_STATUS_SUCCESS;
-
- _cairo_slope_init (&dev_slope, p1, point);
- slope_dx = _cairo_fixed_to_double (point->x - p1->x);
- slope_dy = _cairo_fixed_to_double (point->y - p1->y);
- _compute_normalized_device_slope (&slope_dx, &slope_dy,
- stroker->ctm_inverse, NULL);
-
- status = _cairo_stroker_add_sub_edge (stroker,
- p1, point,
- &dev_slope,
- slope_dx, slope_dy,
- &start, &end);
- if (unlikely (status))
- return status;
-
- if (stroker->has_current_face) {
- /* Join with final face from previous segment */
- status = _cairo_stroker_join (stroker,
- &stroker->current_face,
- &start);
- if (unlikely (status))
- return status;
- } else if (! stroker->has_first_face) {
- /* Save sub path's first face in case needed for closing join */
- stroker->first_face = start;
- stroker->has_first_face = TRUE;
- }
- stroker->current_face = end;
- stroker->has_current_face = TRUE;
-
- stroker->current_point = *point;
-
- return CAIRO_STATUS_SUCCESS;
-}
-
-static cairo_status_t
-_cairo_stroker_spline_to (void *closure,
- const cairo_point_t *point,
- const cairo_slope_t *tangent)
-{
- cairo_stroker_t *stroker = closure;
- cairo_stroke_face_t new_face;
- double slope_dx, slope_dy;
- cairo_point_t points[3];
- cairo_point_t intersect_point;
-
- stroker->has_initial_sub_path = TRUE;
-
- if (stroker->current_point.x == point->x &&
- stroker->current_point.y == point->y)
- return CAIRO_STATUS_SUCCESS;
-
- slope_dx = _cairo_fixed_to_double (tangent->dx);
- slope_dy = _cairo_fixed_to_double (tangent->dy);
-
- if (! _compute_normalized_device_slope (&slope_dx, &slope_dy,
- stroker->ctm_inverse, NULL))
- return CAIRO_STATUS_SUCCESS;
-
- _compute_face (point, tangent,
- slope_dx, slope_dy,
- stroker, &new_face);
-
- assert (stroker->has_current_face);
-
- if ((new_face.dev_slope.x * stroker->current_face.dev_slope.x +
- new_face.dev_slope.y * stroker->current_face.dev_slope.y) < stroker->spline_cusp_tolerance) {
-
- const cairo_point_t *inpt, *outpt;
- int clockwise = _cairo_stroker_join_is_clockwise (&new_face,
- &stroker->current_face);
-
- if (clockwise) {
- inpt = &stroker->current_face.cw;
- outpt = &new_face.cw;
- } else {
- inpt = &stroker->current_face.ccw;
- outpt = &new_face.ccw;
- }
-
- _tessellate_fan (stroker,
- &stroker->current_face.dev_vector,
- &new_face.dev_vector,
- &stroker->current_face.point,
- inpt, outpt,
- clockwise);
- }
-
- if (_slow_segment_intersection (&stroker->current_face.cw,
- &stroker->current_face.ccw,
- &new_face.cw,
- &new_face.ccw,
- &intersect_point)) {
- points[0] = stroker->current_face.ccw;
- points[1] = new_face.ccw;
- points[2] = intersect_point;
- stroker->add_triangle (stroker->closure, points);
-
- points[0] = stroker->current_face.cw;
- points[1] = new_face.cw;
- stroker->add_triangle (stroker->closure, points);
- } else {
- points[0] = stroker->current_face.ccw;
- points[1] = stroker->current_face.cw;
- points[2] = new_face.cw;
- stroker->add_triangle (stroker->closure, points);
-
- points[0] = stroker->current_face.ccw;
- points[1] = new_face.cw;
- points[2] = new_face.ccw;
- stroker->add_triangle (stroker->closure, points);
- }
-
- stroker->current_face = new_face;
- stroker->has_current_face = TRUE;
- stroker->current_point = *point;
-
- return CAIRO_STATUS_SUCCESS;
-}
-
-/*
- * Dashed lines. Cap each dash end, join around turns when on
- */
-static cairo_status_t
-_cairo_stroker_line_to_dashed (void *closure,
- const cairo_point_t *p2)
-{
- cairo_stroker_t *stroker = closure;
- double mag, remain, step_length = 0;
- double slope_dx, slope_dy;
- double dx2, dy2;
- cairo_stroke_face_t sub_start, sub_end;
- cairo_point_t *p1 = &stroker->current_point;
- cairo_slope_t dev_slope;
- cairo_line_t segment;
- cairo_bool_t fully_in_bounds;
- cairo_status_t status;
-
- stroker->has_initial_sub_path = stroker->dash.dash_starts_on;
-
- if (p1->x == p2->x && p1->y == p2->y)
- return CAIRO_STATUS_SUCCESS;
-
- fully_in_bounds = TRUE;
- if (stroker->has_bounds &&
- (! _cairo_box_contains_point (&stroker->bounds, p1) ||
- ! _cairo_box_contains_point (&stroker->bounds, p2)))
- {
- fully_in_bounds = FALSE;
- }
-
- _cairo_slope_init (&dev_slope, p1, p2);
-
- slope_dx = _cairo_fixed_to_double (p2->x - p1->x);
- slope_dy = _cairo_fixed_to_double (p2->y - p1->y);
-
- if (! _compute_normalized_device_slope (&slope_dx, &slope_dy,
- stroker->ctm_inverse, &mag))
- {
- return CAIRO_STATUS_SUCCESS;
- }
-
- remain = mag;
- segment.p1 = *p1;
- while (remain) {
- step_length = MIN (stroker->dash.dash_remain, remain);
- remain -= step_length;
- dx2 = slope_dx * (mag - remain);
- dy2 = slope_dy * (mag - remain);
- cairo_matrix_transform_distance (stroker->ctm, &dx2, &dy2);
- segment.p2.x = _cairo_fixed_from_double (dx2) + p1->x;
- segment.p2.y = _cairo_fixed_from_double (dy2) + p1->y;
-
- if (stroker->dash.dash_on &&
- (fully_in_bounds ||
- (! stroker->has_first_face && stroker->dash.dash_starts_on) ||
- _cairo_box_intersects_line_segment (&stroker->bounds, &segment)))
- {
- status = _cairo_stroker_add_sub_edge (stroker,
- &segment.p1, &segment.p2,
- &dev_slope,
- slope_dx, slope_dy,
- &sub_start, &sub_end);
- if (unlikely (status))
- return status;
-
- if (stroker->has_current_face)
- {
- /* Join with final face from previous segment */
- status = _cairo_stroker_join (stroker,
- &stroker->current_face,
- &sub_start);
- if (unlikely (status))
- return status;
-
- stroker->has_current_face = FALSE;
- }
- else if (! stroker->has_first_face &&
- stroker->dash.dash_starts_on)
- {
- /* Save sub path's first face in case needed for closing join */
- stroker->first_face = sub_start;
- stroker->has_first_face = TRUE;
- }
- else
- {
- /* Cap dash start if not connecting to a previous segment */
- status = _cairo_stroker_add_leading_cap (stroker, &sub_start);
- if (unlikely (status))
- return status;
- }
-
- if (remain) {
- /* Cap dash end if not at end of segment */
- status = _cairo_stroker_add_trailing_cap (stroker, &sub_end);
- if (unlikely (status))
- return status;
- } else {
- stroker->current_face = sub_end;
- stroker->has_current_face = TRUE;
- }
- } else {
- if (stroker->has_current_face) {
- /* Cap final face from previous segment */
- status = _cairo_stroker_add_trailing_cap (stroker,
- &stroker->current_face);
- if (unlikely (status))
- return status;
-
- stroker->has_current_face = FALSE;
- }
- }
-
- _cairo_stroker_dash_step (&stroker->dash, step_length);
- segment.p1 = segment.p2;
- }
-
- if (stroker->dash.dash_on && ! stroker->has_current_face) {
- /* This segment ends on a transition to dash_on, compute a new face
- * and add cap for the beginning of the next dash_on step.
- *
- * Note: this will create a degenerate cap if this is not the last line
- * in the path. Whether this behaviour is desirable or not is debatable.
- * On one side these degenerate caps can not be reproduced with regular
- * path stroking.
- * On the other hand, Acroread 7 also produces the degenerate caps.
- */
- _compute_face (p2, &dev_slope,
- slope_dx, slope_dy,
- stroker,
- &stroker->current_face);
-
- status = _cairo_stroker_add_leading_cap (stroker,
- &stroker->current_face);
- if (unlikely (status))
- return status;
-
- stroker->has_current_face = TRUE;
- }
-
- stroker->current_point = *p2;
-
- return CAIRO_STATUS_SUCCESS;
-}
-
-static cairo_status_t
-_cairo_stroker_curve_to (void *closure,
- const cairo_point_t *b,
- const cairo_point_t *c,
- const cairo_point_t *d)
-{
- cairo_stroker_t *stroker = closure;
- cairo_spline_t spline;
- cairo_line_join_t line_join_save;
- cairo_stroke_face_t face;
- double slope_dx, slope_dy;
- cairo_spline_add_point_func_t line_to;
- cairo_spline_add_point_func_t spline_to;
- cairo_status_t status = CAIRO_STATUS_SUCCESS;
-
- line_to = stroker->dash.dashed ?
- (cairo_spline_add_point_func_t) _cairo_stroker_line_to_dashed :
- (cairo_spline_add_point_func_t) _cairo_stroker_line_to;
-
- /* spline_to is only capable of rendering non-degenerate splines. */
- spline_to = stroker->dash.dashed ?
- (cairo_spline_add_point_func_t) _cairo_stroker_line_to_dashed :
- (cairo_spline_add_point_func_t) _cairo_stroker_spline_to;
-
- if (! _cairo_spline_init (&spline,
- spline_to,
- stroker,
- &stroker->current_point, b, c, d))
- {
- cairo_slope_t fallback_slope;
- _cairo_slope_init (&fallback_slope, &stroker->current_point, d);
- return line_to (closure, d, &fallback_slope);
- }
-
- /* If the line width is so small that the pen is reduced to a
- single point, then we have nothing to do. */
- if (stroker->pen.num_vertices <= 1)
- return CAIRO_STATUS_SUCCESS;
-
- /* Compute the initial face */
- if (! stroker->dash.dashed || stroker->dash.dash_on) {
- slope_dx = _cairo_fixed_to_double (spline.initial_slope.dx);
- slope_dy = _cairo_fixed_to_double (spline.initial_slope.dy);
- if (_compute_normalized_device_slope (&slope_dx, &slope_dy,
- stroker->ctm_inverse, NULL))
- {
- _compute_face (&stroker->current_point,
- &spline.initial_slope,
- slope_dx, slope_dy,
- stroker, &face);
- }
- if (stroker->has_current_face) {
- status = _cairo_stroker_join (stroker,
- &stroker->current_face, &face);
- if (unlikely (status))
- return status;
- } else if (! stroker->has_first_face) {
- stroker->first_face = face;
- stroker->has_first_face = TRUE;
- }
-
- stroker->current_face = face;
- stroker->has_current_face = TRUE;
- }
-
- /* Temporarily modify the stroker to use round joins to guarantee
- * smooth stroked curves. */
- line_join_save = stroker->style.line_join;
- stroker->style.line_join = CAIRO_LINE_JOIN_ROUND;
-
- status = _cairo_spline_decompose (&spline, stroker->tolerance);
- if (unlikely (status))
- return status;
-
- /* And join the final face */
- if (! stroker->dash.dashed || stroker->dash.dash_on) {
- slope_dx = _cairo_fixed_to_double (spline.final_slope.dx);
- slope_dy = _cairo_fixed_to_double (spline.final_slope.dy);
- if (_compute_normalized_device_slope (&slope_dx, &slope_dy,
- stroker->ctm_inverse, NULL))
- {
- _compute_face (&stroker->current_point,
- &spline.final_slope,
- slope_dx, slope_dy,
- stroker, &face);
- }
-
- status = _cairo_stroker_join (stroker, &stroker->current_face, &face);
- if (unlikely (status))
- return status;
-
- stroker->current_face = face;
- }
-
- stroker->style.line_join = line_join_save;
-
- return CAIRO_STATUS_SUCCESS;
-}
-
-static cairo_status_t
-_cairo_stroker_close_path (void *closure)
-{
- cairo_stroker_t *stroker = closure;
- cairo_status_t status;
-
- if (stroker->dash.dashed)
- status = _cairo_stroker_line_to_dashed (stroker, &stroker->first_point);
- else
- status = _cairo_stroker_line_to (stroker, &stroker->first_point);
- if (unlikely (status))
- return status;
-
- if (stroker->has_first_face && stroker->has_current_face) {
- /* Join first and final faces of sub path */
- status = _cairo_stroker_join (stroker,
- &stroker->current_face,
- &stroker->first_face);
- if (unlikely (status))
- return status;
- } else {
- /* Cap the start and end of the sub path as needed */
- status = _cairo_stroker_add_caps (stroker);
- if (unlikely (status))
- return status;
- }
-
- stroker->has_initial_sub_path = FALSE;
- stroker->has_first_face = FALSE;
- stroker->has_current_face = FALSE;
-
- return CAIRO_STATUS_SUCCESS;
-}
-
-cairo_status_t
-_cairo_path_fixed_stroke_to_shaper (cairo_path_fixed_t *path,
- const cairo_stroke_style_t *stroke_style,
- const cairo_matrix_t *ctm,
- const cairo_matrix_t *ctm_inverse,
- double tolerance,
- cairo_status_t (*add_triangle) (void *closure,
- const cairo_point_t triangle[3]),
- cairo_status_t (*add_triangle_fan) (void *closure,
- const cairo_point_t *midpt,
- const cairo_point_t *points,
- int npoints),
- cairo_status_t (*add_convex_quad) (void *closure,
- const cairo_point_t quad[4]),
- void *closure)
-{
- cairo_stroker_t stroker;
- cairo_status_t status;
-
- status = _cairo_stroker_init (&stroker, path, stroke_style,
- ctm, ctm_inverse, tolerance,
- NULL, 0);
- if (unlikely (status))
- return status;
-
- stroker.add_triangle = add_triangle;
- stroker.add_triangle_fan = add_triangle_fan;
- stroker.add_convex_quad = add_convex_quad;
- stroker.closure = closure;
-
- status = _cairo_path_fixed_interpret (path,
- _cairo_stroker_move_to,
- stroker.dash.dashed ?
- _cairo_stroker_line_to_dashed :
- _cairo_stroker_line_to,
- _cairo_stroker_curve_to,
- _cairo_stroker_close_path,
- &stroker);
-
- if (unlikely (status))
- goto BAIL;
-
- /* Cap the start and end of the final sub path as needed */
- status = _cairo_stroker_add_caps (&stroker);
-
-BAIL:
- _cairo_stroker_fini (&stroker);
-
- return status;
-}
-
-cairo_status_t
-_cairo_path_fixed_stroke_dashed_to_polygon (const cairo_path_fixed_t *path,
- const cairo_stroke_style_t *stroke_style,
- const cairo_matrix_t *ctm,
- const cairo_matrix_t *ctm_inverse,
- double tolerance,
- cairo_polygon_t *polygon)
-{
- cairo_stroker_t stroker;
- cairo_status_t status;
-
- status = _cairo_stroker_init (&stroker, path, stroke_style,
- ctm, ctm_inverse, tolerance,
- polygon->limits, polygon->num_limits);
- if (unlikely (status))
- return status;
-
- stroker.add_external_edge = _cairo_polygon_add_external_edge,
- stroker.closure = polygon;
-
- status = _cairo_path_fixed_interpret (path,
- _cairo_stroker_move_to,
- stroker.dash.dashed ?
- _cairo_stroker_line_to_dashed :
- _cairo_stroker_line_to,
- _cairo_stroker_curve_to,
- _cairo_stroker_close_path,
- &stroker);
-
- if (unlikely (status))
- goto BAIL;
-
- /* Cap the start and end of the final sub path as needed */
- status = _cairo_stroker_add_caps (&stroker);
-
-BAIL:
- _cairo_stroker_fini (&stroker);
-
- return status;
-}
-
-cairo_int_status_t
-_cairo_path_fixed_stroke_polygon_to_traps (const cairo_path_fixed_t *path,
- const cairo_stroke_style_t *stroke_style,
- const cairo_matrix_t *ctm,
- const cairo_matrix_t *ctm_inverse,
- double tolerance,
- cairo_traps_t *traps)
-{
- cairo_int_status_t status;
- cairo_polygon_t polygon;
-
- _cairo_polygon_init (&polygon, traps->limits, traps->num_limits);
- status = _cairo_path_fixed_stroke_to_polygon (path,
- stroke_style,
- ctm,
- ctm_inverse,
- tolerance,
- &polygon);
- if (unlikely (status))
- goto BAIL;
-
- status = _cairo_polygon_status (&polygon);
- if (unlikely (status))
- goto BAIL;
-
- status = _cairo_bentley_ottmann_tessellate_polygon (traps, &polygon,
- CAIRO_FILL_RULE_WINDING);
-
-BAIL:
- _cairo_polygon_fini (&polygon);
-
- return status;
-}