/*
* 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 <iostream>
#include <fstream>
#include <gerbolyze.hpp>
#include "svg_import_defs.h"
#include "svg_color.h"
#include "svg_geom.h"
#include "svg_path.h"
#include "vec_core.h"
using namespace gerbolyze;
using namespace std;
using namespace ClipperLib;
bool gerbolyze::SVGDocument::load(string filename) {
ifstream in_f;
in_f.open(filename);
return in_f && load(in_f);
}
bool gerbolyze::SVGDocument::load(istream &in) {
/* Load XML document */
auto res = svg_doc.load(in);
if (!res) {
cerr << "Cannot parse input file" << endl;
return false;
}
root_elem = svg_doc.child("svg");
if (!root_elem) {
cerr << "Input file is missing root <svg> element" << endl;
return false;
}
/* Set up the document's viewport transform */
istringstream vb_stream(root_elem.attribute("viewBox").value());
vb_stream >> vb_x >> vb_y >> vb_w >> vb_h;
cerr << "SVG document viewbox: origin=" << vb_x << "," << vb_y << ", size=" << vb_w << "," << vb_h << endl;
page_w = usvg_double_attr(root_elem, "width");
page_h = usvg_double_attr(root_elem, "height");
/* usvg resolves all units, but instead of outputting some reasonable absolute length like mm, it converts
* everything to px, which depends on usvg's DPI setting (--dpi).
*/
page_w_mm = page_w / assumed_usvg_dpi * 25.4;
page_h_mm = page_h / assumed_usvg_dpi * 25.4;
if (!(page_w_mm > 0.0 && page_h_mm > 0.0 && page_w_mm < 10e3 && page_h_mm < 10e3)) {
cerr << "Warning: Page has zero or negative size, or is larger than 10 x 10 meters! Parsed size: " << page_w << " x " << page_h << " millimeter" << endl;
}
if (fabs((vb_w / page_w) / (vb_h / page_h) - 1.0) > 0.001) {
cerr << "Warning: Document has different document unit scale in x and y direction! Output will likely be garbage!" << endl;
}
/* Get the one document defs element */
defs_node = root_elem.child("defs");
if (!defs_node) {
cerr << "Warning: Input file is missing <defs> node" << endl;
}
setup_viewport_clip();
load_patterns();
_valid = true;
return true;
}
const Paths *gerbolyze::SVGDocument::lookup_clip_path(const pugi::xml_node &node) {
string id(usvg_id_url(node.attribute("clip-path").value()));
if (id.empty() || clip_path_map.count(id) == 0) {
return nullptr;
}
return &clip_path_map[id];
}
Pattern *gerbolyze::SVGDocument::lookup_pattern(const string id) {
if (id.empty() || pattern_map.count(id) == 0) {
return nullptr;
}
return &pattern_map[id];
};
/* Used to convert mm values from configuration such as the minimum feature size into document units. */
double gerbolyze::SVGDocument::mm_to_doc_units(double mm) const {
return mm * (vb_w / page_w_mm);
}
double gerbolyze::SVGDocument::doc_units_to_mm(double px) const {
return px / (vb_w / page_w_mm);
}
bool IDElementSelector::match(const pugi::xml_node &node, bool is_toplevel, bool parent_include) const {
string id = node.attribute("id").value();
//cerr << "match id=" << id << " toplevel=" << is_toplevel << " parent=" << parent_include << endl;
if (is_toplevel && layers) {
bool layer_match = std::find(layers->begin(), layers->end(), id) != layers->end();
if (!layer_match) {
cerr << "Rejecting layer \"" << id << "\"" << endl;
return false;
}
}
if (include.empty() && exclude.empty())
return true;
bool include_match = std::find(include.begin(), include.end(), id) != include.end();
bool exclude_match = std::find(exclude.begin(), exclude.end(), id) != exclude.end();
//cerr << " excl=" << exclude_match << " incl=" << include_match << endl;
if (is_toplevel) {
if (!include.empty())
parent_include = false;
else
parent_include = true;
}
if (exclude_match) {
return false;
}
if (include_match) {
return true;
}
return parent_include;
}
/* Recursively export all SVG elements in the given group. */
void gerbolyze::SVGDocument::export_svg_group(RenderContext &ctx, const pugi::xml_node &group) {
/* Fetch clip path from global registry and transform it into document coordinates. */
Paths clip_path;
auto *lookup = lookup_clip_path(group);
if (!lookup) {
string id(usvg_id_url(group.attribute("clip-path").value()));
if (!id.empty()) {
cerr << "Warning: Cannot find clip path with ID \"" << group.attribute("clip-path").value() << "\" for group \"" << group.attribute("id").value() << "\"." << endl;
}
} else {
clip_path = *lookup;
ctx.mat().transform_paths(clip_path);
}
/* Clip against parent's clip path (both are now in document coordinates) */
if (!ctx.clip().empty()) {
if (!clip_path.empty()) {
Clipper c;
c.StrictlySimple(true);
c.AddPaths(ctx.clip(), ptClip, /* closed */ true);
c.AddPaths(clip_path, ptSubject, /* closed */ true);
/* Nonzero fill since both input clip paths must already have been preprocessed by clipper. */
c.Execute(ctIntersection, clip_path, pftNonZero);
} else {
clip_path = ctx.clip();
}
}
/* Iterate over the group's children, exporting them one by one. */
for (const auto &node : group.children()) {
string name(node.name());
bool match = ctx.match(node);
RenderContext elem_ctx(ctx, xform2d(node.attribute("transform").value()), clip_path, match);
if (name == "g") {
if (ctx.root()) { /* Treat top-level groups as "layers" like inkscape does. */
cerr << "Forwarding layer name to sink: \"" << node.attribute("id").value() << "\"" << endl;
LayerNameToken tok { node.attribute("id").value() };
elem_ctx.sink() << tok;
}
export_svg_group(elem_ctx, node);
if (ctx.root()) {
LayerNameToken tok {""};
elem_ctx.sink() << tok;
}
} else if (name == "path") {
if (!match)
continue;
export_svg_path(elem_ctx, node);
} else if (name == "image") {
if (!match)
continue;
ImageVectorizer *vec = ctx.settings().m_vec_sel.select(node);
if (!vec) {
cerr << "Cannot resolve vectorizer for node \"" << node.attribute("id").value() << "\"" << endl;
continue;
}
double min_feature_size_px = mm_to_doc_units(ctx.settings().m_minimum_feature_size_mm);
vec->vectorize_image(elem_ctx, node, min_feature_size_px);
delete vec;
} else if (name == "defs") {
/* ignore */
} else {
cerr << " Unexpected child: <" << node.name() << ">" << endl;
}
}
}
/* Export an SVG path element to gerber. Apply patterns and clip on the fly. */
void gerbolyze::SVGDocument::export_svg_path(RenderContext &ctx, const pugi::xml_node &node) {
enum gerber_color fill_color = gerber_fill_color(node, ctx.settings());
enum gerber_color stroke_color = gerber_stroke_color(node, ctx.settings());
//cerr << "path: resolved colors, stroke=" << stroke_color << ", fill=" << fill_color << endl;
double stroke_width = usvg_double_attr(node, "stroke-width", /* default */ 1.0);
assert(stroke_width > 0.0);
enum ClipperLib::EndType end_type = clipper_end_type(node);
enum ClipperLib::JoinType join_type = clipper_join_type(node);
vector<double> dasharray;
parse_dasharray(node, dasharray);
double stroke_dashoffset = usvg_double_attr(node, "stroke-dashoffset", /* default */ 0.0);
double stroke_miterlimit = usvg_double_attr(node, "stroke-miterlimit", /* default */ 4.0);
if (!fill_color && !stroke_color) { /* Ignore "transparent" paths */
return;
}
/* Load path from SVG path data and transform into document units. */
/* FIXME transform stroke width here? */
stroke_width = ctx.mat().doc2phys_dist(stroke_width);
Paths stroke_open, stroke_closed;
PolyTree ptree_fill;
PolyTree ptree;
load_svg_path(ctx.mat(), node, stroke_open, stroke_closed, ptree_fill, ctx.settings().curve_tolerance_mm);
Paths fill_paths;
PolyTreeToPaths(ptree_fill, fill_paths);
bool has_fill = fill_color;
bool has_stroke = stroke_color && stroke_width > 0.0;
/* Skip filling for transparent fills. In outline mode, skip filling if a stroke is also set to avoid double lines.
*/
if (has_fill && !(ctx.settings().outline_mode && has_stroke)) {
/* Clip paths. Consider all paths closed for filling. */
if (!ctx.clip().empty()) {
Clipper c;
c.AddPaths(fill_paths, ptSubject, /* closed */ true);
c.AddPaths(ctx.clip(), ptClip, /* closed */ true);
c.StrictlySimple(true);
/* fill rules are nonzero since both subject and clip have already been normalized by clipper. */
c.Execute(ctIntersection, ptree_fill, pftNonZero, pftNonZero);
}
/* Call out to pattern tiler for pattern fills. The path becomes the clip here. */
if (fill_color == GRB_PATTERN_FILL) {
string fill_pattern_id = usvg_id_url(node.attribute("fill").value());
Pattern *pattern = lookup_pattern(fill_pattern_id);
if (!pattern) {
cerr << "Warning: Fill pattern with id \"" << fill_pattern_id << "\" not found." << endl;
} else {
PolyTreeToPaths(ptree_fill, fill_paths);
RenderContext local_ctx(ctx, xform2d(), fill_paths, true);
pattern->tile(local_ctx);
}
} else { /* solid fill */
if (ctx.settings().outline_mode) {
fill_color = GRB_DARK;
}
Paths f_polys;
/* Important for gerber spec compliance and also for reliable rendering results irrespective of board house
* and gerber viewer. */
dehole_polytree(ptree_fill, f_polys);
/* export gerber */
for (const auto &poly : f_polys) {
vector<array<double, 2>> out;
for (const auto &p : poly)
out.push_back(std::array<double, 2>{
((double)p.X) / clipper_scale, ((double)p.Y) / clipper_scale
});
/* In outline mode, manually close polys */
if (ctx.settings().outline_mode && !out.empty())
out.push_back(out[0]);
ctx.sink() << (fill_color == GRB_DARK ? GRB_POL_DARK : GRB_POL_CLEAR) << out;
}
}
}
if (has_stroke) {
ClipperOffset offx;
offx.ArcTolerance = 0.01 * clipper_scale; /* 10µm; TODO: Make this configurable */
offx.MiterLimit = stroke_miterlimit;
/* For stroking we have to separately handle open and closed paths */
for (auto &poly : stroke_closed) {
if (poly.empty())
continue;
/* Special case: A closed path becomes a number of open paths when it is dashed. */
if (dasharray.empty()) {
if (ctx.settings().outline_mode && stroke_color != GRB_PATTERN_FILL) {
/* In outline mode, manually close polys */
poly.push_back(poly[0]);
ctx.sink() << ApertureToken() << poly;
} else {
offx.AddPath(poly, join_type, etClosedLine);
}
} else {
Path poly_copy(poly);
poly_copy.push_back(poly[0]);
Paths out;
dash_path(poly_copy, out, dasharray, stroke_dashoffset);
if (ctx.settings().outline_mode && stroke_color != GRB_PATTERN_FILL) {
ctx.sink() << ApertureToken(stroke_width) << out;
} else {
offx.AddPaths(out, join_type, end_type);
}
}
}
for (const auto &poly : stroke_open) {
Paths out;
dash_path(poly, out, dasharray, stroke_dashoffset);
if (ctx.settings().outline_mode && stroke_color != GRB_PATTERN_FILL) {
ctx.sink() << ApertureToken(stroke_width) << out;
} else {
offx.AddPaths(out, join_type, end_type);
}
}
/* Execute clipper offset operation to generate stroke outlines */
offx.Execute(ptree, 0.5 * stroke_width * clipper_scale);
/* Clip. Note that after the outline, all we have is closed paths as any open path's stroke outline is itself
* a closed path. */
if (!ctx.clip().empty()) {
Clipper c;
Paths outline_paths;
PolyTreeToPaths(ptree, outline_paths);
c.AddPaths(outline_paths, ptSubject, /* closed */ true);
c.AddPaths(ctx.clip(), ptClip, /* closed */ true);
c.StrictlySimple(true);
/* fill rules are nonzero since both subject and clip have already been normalized by clipper. */
c.Execute(ctIntersection, ptree, pftNonZero, pftNonZero);
}
/* Call out to pattern tiler for pattern strokes. The stroke's outline becomes the clip here. */
if (stroke_color == GRB_PATTERN_FILL) {
string stroke_pattern_id = usvg_id_url(node.attribute("stroke").value());
Pattern *pattern = lookup_pattern(stroke_pattern_id);
if (!pattern) {
cerr << "Warning: Fill pattern with id \"" << stroke_pattern_id << "\" not found." << endl;
} else {
Paths clip;
PolyTreeToPaths(ptree, clip);
RenderContext local_ctx(ctx, xform2d(), clip, true);
pattern->tile(local_ctx);
}
} else if (!ctx.settings().outline_mode) {
Paths s_polys;
dehole_polytree(ptree, s_polys);
ctx.sink() << ApertureToken() << (stroke_color == GRB_DARK ? GRB_POL_DARK : GRB_POL_CLEAR) << s_polys;
}
}
ctx.sink() << ApertureToken();
}
void gerbolyze::SVGDocument::render(const RenderSettings &rset, PolygonSink &sink, const ElementSelector &sel) {
assert(_valid);
/* Export the actual SVG document. We do this as we go, i.e. we immediately process each element to gerber as we
* encounter it instead of first rendering everything to a giant list of gerber primitives and then serializing
* those later. Exporting them on the fly saves a ton of memory and is much faster.
*/
/* Scale document pixels to mm for sinks */
PolygonScaler scaler(sink, doc_units_to_mm(1.0));
RenderContext ctx(rset, scaler, sel, vb_paths);
/* Load clip paths from defs with given bezier flattening tolerance and unit scale */
load_clips(rset);
scaler.header({vb_x, vb_y}, {vb_w, vb_h});
export_svg_group(ctx, root_elem);
scaler.footer();
}
void gerbolyze::SVGDocument::render_to_list(const RenderSettings &rset, vector<pair<Polygon, GerberPolarityToken>> &out, const ElementSelector &sel) {
LambdaPolygonSink sink([&out](const Polygon &poly, GerberPolarityToken pol) {
out.emplace_back(pair<Polygon, GerberPolarityToken>{poly, pol});
});
render(rset, sink, sel);
}
void gerbolyze::SVGDocument::setup_viewport_clip() {
/* Set up view port clip path */
Path vb_path;
for (d2p &p : vector<d2p> {
{vb_x, vb_y},
{vb_x+vb_w, vb_y},
{vb_x+vb_w, vb_y+vb_h},
{vb_x, vb_y+vb_h}}) {
vb_path.push_back({ (cInt)round(p[0] * clipper_scale), (cInt)round(p[1] * clipper_scale) });
}
vb_paths.push_back(vb_path);
}
void gerbolyze::SVGDocument::load_patterns() {
/* Set up document-wide pattern registry. Load patterns from <defs> node. */
for (const auto &node : defs_node.children("pattern")) {
pattern_map.emplace(std::piecewise_construct, std::forward_as_tuple(node.attribute("id").value()), std::forward_as_tuple(node, *this));
}
}
void gerbolyze::SVGDocument::load_clips(const RenderSettings &rset) {
/* Set up document-wide clip path registry: Extract clip path definitions from <defs> element */
for (const auto &node : defs_node.children("clipPath")) {
xform2d local_xf(node.attribute("transform").value());
string meta_clip_path_id(usvg_id_url(node.attribute("clip-path").value()));
Clipper c;
/* The clipPath node can only contain <path> children. usvg converts all geometric objects (rect etc.) to
* <path>s. Raster images are invalid inside a clip path. usvg removes all groups that are not relevant to
* rendering, and the only way a group might stay is if it affects rasterization (e.g. through mask, clipPath).
*/
for (const auto &child : node.children("path")) {
Paths _stroke_open, _stroke_closed; /* discarded */
PolyTree ptree_fill;
/* TODO: we currently only support clipPathUnits="userSpaceOnUse", not "objectBoundingBox". */
xform2d child_xf(local_xf);
child_xf.transform(xform2d(child.attribute("transform").value()));
load_svg_path(child_xf, child, _stroke_open, _stroke_closed, ptree_fill, rset.curve_tolerance_mm);
Paths paths;
PolyTreeToPaths(ptree_fill, paths);
c.AddPaths(paths, ptSubject, /* closed */ false);
}
/* Support clip paths that themselves have clip paths */
if (!meta_clip_path_id.empty()) {
if (clip_path_map.count(meta_clip_path_id) > 0) {
/* all clip paths must be closed */
c.AddPaths(clip_path_map[meta_clip_path_id], ptClip, /* closed */ true);
} else {
cerr << "Warning: Cannot find clip path with ID \"" << meta_clip_path_id << "\", ignoring." << endl;
}
}
PolyTree ptree;
c.StrictlySimple(true);
/* This unions all child <path>s together and at the same time applies any meta clip path. */
/* The fill rules are both nonzero since both subject and clip have already been normalized by clipper. */
c.Execute(ctUnion, ptree, pftNonZero, pftNonZero);
/* Insert into document clip path map */
PolyTreeToPaths(ptree, clip_path_map[node.attribute("id").value()]);
}
}
gerbolyze::RenderContext::RenderContext(const RenderSettings &settings,
PolygonSink &sink,
const ElementSelector &sel,
ClipperLib::Paths &clip) :
m_sink(sink),
m_settings(settings),
m_mat(),
m_root(true),
m_included(false),
m_sel(sel),
m_clip(clip)
{
}
gerbolyze::RenderContext::RenderContext(RenderContext &parent, xform2d transform) :
RenderContext(parent, transform, parent.clip(), parent.included())
{
}
gerbolyze::RenderContext::RenderContext(RenderContext &parent, xform2d transform, ClipperLib::Paths &clip, bool included) :
m_sink(parent.sink()),
m_settings(parent.settings()),
m_mat(parent.mat()),
m_root(false),
m_included(included),
m_sel(parent.sel()),
m_clip(clip)
{
m_mat.transform(transform);
}