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Diffstat (limited to 'svg-flatten/src/svg_pattern.cpp')
| -rw-r--r-- | svg-flatten/src/svg_pattern.cpp | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/svg-flatten/src/svg_pattern.cpp b/svg-flatten/src/svg_pattern.cpp new file mode 100644 index 0000000..b62df28 --- /dev/null +++ b/svg-flatten/src/svg_pattern.cpp @@ -0,0 +1,113 @@ +/* + * 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 <assert.h> +#include "svg_import_util.h" +#include "svg_pattern.h" +#include "svg_import_defs.h" +#include "svg_geom.h" +#include <gerbolyze.hpp> + +using namespace std; + +gerbolyze::Pattern::Pattern(const pugi::xml_node &node, SVGDocument &doc) : _node(node), doc(&doc) { + /* Read pattern attributes from SVG node */ + cerr << "creating pattern for node with id \"" << node.attribute("id").value() << "\"" << endl; + x = usvg_double_attr(node, "x"); + y = usvg_double_attr(node, "y"); + w = usvg_double_attr(node, "width"); + h = usvg_double_attr(node, "height"); + patternTransform = node.attribute("patternTransform").value(); + + string vb_s(node.attribute("viewBox").value()); + has_vb = !vb_s.empty(); + if (has_vb) { + istringstream vb_stream(vb_s); + vb_stream >> vb_x >> vb_y >> vb_w >> vb_h; + } + + patternUnits = map_str_to_units(node.attribute("patternUnits").value(), SVG_ObjectBoundingBox); + patternContentUnits = map_str_to_units(node.attribute("patternContentUnits").value(), SVG_UserSpaceOnUse); +} + +/* Tile pattern into gerber. Note that this function may be called several times in case the pattern is + * referenced from multiple places, so we must not clobber any of the object's state. */ +void gerbolyze::Pattern::tile (const gerbolyze::RenderSettings &rset, ClipperLib::Paths &clip) { + assert(doc); + cairo_t *cr = doc->cairo(); + assert(cr); + + cairo_save(cr); + /* Transform x, y, w, h from pattern coordinate space into parent coordinates by applying the inverse + * patternTransform. This is necessary so we iterate over the correct bounds when tiling below */ + cairo_matrix_t mat; + load_cairo_matrix_from_svg(patternTransform, mat); + if (cairo_matrix_invert(&mat) != CAIRO_STATUS_SUCCESS) { + cerr << "Cannot invert patternTransform matrix on pattern \"" << _node.attribute("id").value() << "\"." << endl; + cairo_restore(cr); + } + double inst_x = x, inst_y = y, inst_w = w, inst_h = h; + cairo_user_to_device(cr, &inst_x, &inst_y); + cairo_user_to_device_distance(cr, &inst_w, &inst_h); + cairo_restore(cr); + + ClipperLib::IntRect clip_bounds = get_paths_bounds(clip); + double bx = clip_bounds.left / clipper_scale; + double by = clip_bounds.top / clipper_scale; + double bw = (clip_bounds.right - clip_bounds.left) / clipper_scale; + double bh = (clip_bounds.bottom - clip_bounds.top) / clipper_scale; + + if (patternUnits == SVG_ObjectBoundingBox) { + inst_x *= bw; + inst_y *= bh; + inst_w *= bw; + inst_h *= bh; + } + + /* Switch to pattern coordinates */ + cairo_save(cr); + cairo_translate(cr, bx, by); + apply_cairo_transform_from_svg(cr, patternTransform); + + /* Iterate over all pattern tiles in pattern coordinates */ + for (double inst_off_x = fmod(inst_x, inst_w) - inst_w; + inst_off_x < bw + inst_w; + inst_off_x += inst_w) { + + for (double inst_off_y = fmod(inst_y, inst_h) - inst_h; + inst_off_y < bh + inst_h; + inst_off_y += inst_h) { + + cairo_save(cr); + /* Change into this individual tile's coordinate system */ + cairo_translate(cr, inst_off_x, inst_off_y); + if (has_vb) { + cairo_translate(cr, vb_x, vb_y); + cairo_scale(cr, inst_w / vb_w, inst_h / vb_h); + } else if (patternContentUnits == SVG_ObjectBoundingBox) { + cairo_scale(cr, bw, bh); + } + + /* Export the pattern tile's content like a group */ + doc->export_svg_group(rset, _node, clip); + cairo_restore(cr); + } + } + cairo_restore(cr); +} + |