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-rw-r--r--src/svg_path.cpp213
1 files changed, 0 insertions, 213 deletions
diff --git a/src/svg_path.cpp b/src/svg_path.cpp
deleted file mode 100644
index 537b5dd..0000000
--- a/src/svg_path.cpp
+++ /dev/null
@@ -1,213 +0,0 @@
-/*
- * This file is part of gerbolyze, a vector image preprocessing toolchain
- * Copyright (C) 2021 Jan Sebastian Götte <gerbolyze@jaseg.de>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program 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 Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see <https://www.gnu.org/licenses/>.
- */
-
-#include <cmath>
-#include <assert.h>
-#include <iostream>
-#include <sstream>
-#include "cairo_clipper.hpp"
-#include "svg_import_defs.h"
-#include "svg_path.h"
-
-using namespace std;
-
-static void clipper_add_cairo_path(cairo_t *cr, ClipperLib::Clipper &c, bool closed) {
- ClipperLib::Paths in_poly;
- ClipperLib::cairo::cairo_to_clipper(cr, in_poly, CAIRO_PRECISION, ClipperLib::cairo::tNone);
- c.AddPaths(in_poly, ClipperLib::ptSubject, closed);
-}
-
-static void path_to_clipper_via_cairo(cairo_t *cr, ClipperLib::Clipper &c, const pugi::char_t *path_data) {
- istringstream d(path_data);
-
- string cmd;
- double x, y, c1x, c1y, c2x, c2y;
-
- bool first = true;
- bool path_is_empty = true;
- while (!d.eof()) {
- d >> cmd;
- assert (!d.fail());
- assert(!first || cmd == "M");
-
- if (cmd == "Z") { /* Close path */
- cairo_close_path(cr);
- clipper_add_cairo_path(cr, c, /* closed= */ true);
- cairo_new_path(cr);
- path_is_empty = true;
-
- } else if (cmd == "M") { /* Move to */
- d >> x >> y;
- /* We need to transform all points ourselves here, and cannot use the transform feature of cairo_to_clipper:
- * Our transform may contain offsets, and clipper only passes its data into cairo's transform functions
- * after scaling up to its internal fixed-point ints, but it does not scale the transform accordingly. This
- * means a scale/rotation we set before calling clipper works out fine, but translations get lost as they
- * get scaled by something like 1e-6.
- */
- cairo_user_to_device(cr, &x, &y);
- assert (!d.fail());
- if (!first)
- clipper_add_cairo_path(cr, c, /* closed= */ false);
- cairo_new_path (cr);
- path_is_empty = true;
- cairo_move_to(cr, x, y);
-
- } else if (cmd == "L") { /* Line to */
- d >> x >> y;
- cairo_user_to_device(cr, &x, &y);
- assert (!d.fail());
- cairo_line_to(cr, x, y);
- path_is_empty = false;
-
- } else { /* Curve to */
- assert(cmd == "C");
- d >> c1x >> c1y; /* first control point */
- cairo_user_to_device(cr, &c1x, &c1y);
- d >> c2x >> c2y; /* second control point */
- cairo_user_to_device(cr, &c2x, &c2y);
- d >> x >> y; /* end point */
- cairo_user_to_device(cr, &x, &y);
- assert (!d.fail());
- cairo_curve_to(cr, c1x, c1y, c2x, c2y, x, y);
- path_is_empty = false;
- }
-
- first = false;
- }
- if (!path_is_empty) {
- cairo_close_path(cr);
- clipper_add_cairo_path(cr, c, /* closed= */ false);
- }
-}
-
-void gerbolyze::load_svg_path(cairo_t *cr, const pugi::xml_node &node, ClipperLib::PolyTree &ptree) {
- auto *path_data = node.attribute("d").value();
- auto fill_rule = clipper_fill_rule(node);
-
- /* For open paths, clipper does not correctly remove self-intersections. Thus, we pass everything into
- * clipper twice: Once with all paths set to "closed" to compute fill areas, and once with correct
- * open/closed properties for stroke offsetting. */
- cairo_set_tolerance (cr, 0.1); /* FIXME make configurable, scale properly for units */
- cairo_set_fill_rule(cr, CAIRO_FILL_RULE_WINDING);
-
- ClipperLib::Clipper c;
- c.StrictlySimple(true);
- path_to_clipper_via_cairo(cr, c, path_data);
- /* We canont clip the polygon here since that would produce incorrect results for our stroke. */
- c.Execute(ClipperLib::ctUnion, ptree, fill_rule, ClipperLib::pftNonZero);
-}
-
-void gerbolyze::parse_dasharray(const pugi::xml_node &node, vector<double> &out) {
- out.clear();
-
- string val(node.attribute("stroke-dasharray").value());
- if (val.empty() || val == "none")
- return;
-
- istringstream desc_stream(val);
- while (!desc_stream.eof()) {
- /* usvg says the array only contains unitless (px) values. I don't know what resvg does with percentages inside
- * dash arrays. We just assume everything is a unitless number here. In case usvg passes through percentages,
- * well, bad luck. They are a kind of weird thing inside a dash array in the first place. */
- double d;
- desc_stream >> d;
- out.push_back(d);
- }
-
- assert(out.size() % 2 == 0); /* according to resvg spec */
-}
-
-/* Take a Clipper path in clipper-scaled document units, and apply the given SVG dash array to it. Do this by walking
- * the path from start to end while emitting dashes. */
-void gerbolyze::dash_path(const ClipperLib::Path &in, ClipperLib::Paths &out, const vector<double> dasharray, double dash_offset) {
- out.clear();
- if (dasharray.empty() || in.size() < 2) {
- out.push_back(in);
- return;
- }
-
- size_t dash_idx = 0;
- size_t num_dashes = dasharray.size();
- while (dash_offset > dasharray[dash_idx]) {
- dash_offset -= dasharray[dash_idx];
- dash_idx = (dash_idx + 1) % num_dashes;
- }
-
- double dash_remaining = dasharray[dash_idx] - dash_offset;
-
- ClipperLib::Path current_dash;
- current_dash.push_back(in[0]);
- double dbg_total_len = 0.0;
- for (size_t i=1; i<in.size(); i++) {
- ClipperLib::IntPoint p1(in[i-1]), p2(in[i]);
-
- double x1 = p1.X / clipper_scale, y1 = p1.Y / clipper_scale, x2 = p2.X / clipper_scale, y2 = p2.Y / clipper_scale;
- double dist = sqrt(pow(x2-x1, 2) + pow(y2-y1, 2));
- dbg_total_len += dist;
-
- if (dist < dash_remaining) {
- /* dash extends beyond this segment, append this segment and continue. */
- dash_remaining -= dist;
- current_dash.push_back(p2);
-
- } else {
- /* dash started in some previous segment ends in this segment */
- double dash_frac = dash_remaining/dist;
- double x = x1 + (x2 - x1) * dash_frac,
- y = y1 + (y2 - y1) * dash_frac;
- ClipperLib::IntPoint intermediate {(ClipperLib::cInt)round(x * clipper_scale), (ClipperLib::cInt)round(y * clipper_scale)};
-
- /* end this dash */
- current_dash.push_back(intermediate);
- if (dash_idx%2 == 0) { /* dash */
- out.push_back(current_dash);
- } /* else space */
- dash_idx = (dash_idx + 1) % num_dashes;
- double offset = dash_remaining;
-
- /* start next dash */
- current_dash.clear();
- current_dash.push_back(intermediate);
-
- /* handle case where multiple dashes fit into this segment */
- while ((dist - offset) > dasharray[dash_idx]) {
- offset += dasharray[dash_idx];
-
- double dash_frac = offset/dist;
- double x = x1 + (x2 - x1) * dash_frac,
- y = y1 + (y2 - y1) * dash_frac;
- ClipperLib::IntPoint intermediate {(ClipperLib::cInt)round(x * clipper_scale), (ClipperLib::cInt)round(y * clipper_scale)};
-
- /* end this dash */
- current_dash.push_back(intermediate);
- if (dash_idx%2 == 0) { /* dash */
- out.push_back(current_dash);
- } /* else space */
- dash_idx = (dash_idx + 1) % num_dashes;
-
- /* start next dash */
- current_dash.clear();
- current_dash.push_back(intermediate);
- }
-
- dash_remaining = dasharray[dash_idx] - (dist - offset);
- current_dash.push_back(p2);
- }
- }
-}
-
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