Reorg: move svg-flatten files into subdir

1 files changed, 123 insertions, 0 deletions

diff --git a/svg-flatten/src/svg_import_util.cpp b/svg-flatten/src/svg_import_util.cpp
new file mode 100644
index 0000000..efa7701
--- /dev/null
+++ b/svg-flatten/src/svg_import_util.cpp
@@ -0,0 +1,123 @@
+/*
+ * 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 "base64.h"
+#include "svg_import_util.h"
+
+using namespace std;
+
+void gerbolyze::print_matrix(cairo_t *cr, bool print_examples) {
+    cairo_matrix_t mat;
+    cairo_get_matrix(cr, &mat);
+    cerr << "    xform matrix = { xx=" << mat.xx << ", yx=" << mat.yx << ", xy=" << mat.xy << ", yy=" << mat.yy << ", x0=" << mat.x0 << ", y0=" << mat.y0 << " }" << endl;
+    if (print_examples) {
+        double x=0, y=0;
+        cairo_user_to_device(cr, &x, &y);
+        cerr << "        (0, 0) -> (" << x << ", " << y << ")" << endl;
+        x = 1, y = 0;
+        cairo_user_to_device(cr, &x, &y);
+        cerr << "        (1, 0) -> (" << x << ", " << y << ")" << endl;
+        x = 0, y = 1;
+        cairo_user_to_device(cr, &x, &y);
+        cerr << "        (0, 1) -> (" << x << ", " << y << ")" << endl;
+        x = 1, y = 1;
+        cairo_user_to_device(cr, &x, &y);
+        cerr << "        (1, 1) -> (" << x << ", " << y << ")" << endl;
+    }
+}
+
+/* Read a double value formatted like usvg formats doubles from an SVG attribute */
+double gerbolyze::usvg_double_attr(const pugi::xml_node &node, const char *attr, double default_value) {
+    const auto *val = node.attribute(attr).value();
+    if (*val == '\0')
+        return default_value;
+
+    return atof(val);
+}
+
+/* Read an url from an usvg attribute */
+string gerbolyze::usvg_id_url(string attr) {
+    if (attr.rfind("url(#", 0) == string::npos)
+        return string();
+
+    attr = attr.substr(strlen("url(#"));
+    attr = attr.substr(0, attr.size()-1);
+    return attr;
+}
+
+gerbolyze::RelativeUnits gerbolyze::map_str_to_units(string str, gerbolyze::RelativeUnits default_val) {
+    if (str == "objectBoundingBox")
+        return SVG_ObjectBoundingBox;
+    else if (str == "userSpaceOnUse")
+        return SVG_UserSpaceOnUse;
+    return default_val;
+}
+
+void gerbolyze::load_cairo_matrix_from_svg(const string &transform, cairo_matrix_t &mat) {
+    if (transform.empty()) {
+        cairo_matrix_init_identity(&mat);
+        return;
+    }
+
+    string start("matrix(");
+    assert(transform.substr(0, start.length()) == start);
+    assert(transform.back() == ')');
+    const string &foo = transform.substr(start.length(), transform.length());
+    const string &bar = foo.substr(0, foo.length() - 1);
+
+    istringstream xform(bar);
+
+    double a, c, e,
+           b, d, f;
+    xform >> a >> b >> c >> d >> e >> f;
+    assert(!xform.fail());
+
+    cairo_matrix_init(&mat, a, b, c, d, e, f);
+}
+
+void gerbolyze::apply_cairo_transform_from_svg(cairo_t *cr, const string &transform) {
+    cairo_matrix_t mat;
+    load_cairo_matrix_from_svg(transform, mat);
+    cairo_transform(cr, &mat); /* or cairo_transform? */
+}
+
+/* Cf. https://tools.ietf.org/html/rfc2397 */
+string gerbolyze::parse_data_iri(const string &data_url) {
+    if (data_url.rfind("data:", 0) == string::npos) /* check if url starts with "data:" */
+        return string();
+
+    size_t foo = data_url.find("base64,");
+    if (foo == string::npos) /* check if this is actually a data URL */
+        return string();
+
+    size_t b64_begin = data_url.find_first_not_of(" ", foo + strlen("base64,"));
+    assert(b64_begin != string::npos);
+
+    return base64_decode(data_url.substr(b64_begin));
+}
+
+/* for debug svg output */
+void gerbolyze::apply_viewport_matrix(cairo_t *cr, cairo_matrix_t &viewport_matrix) {
+    /* Multiply viewport matrix *from the left*, i.e. as if it had been applied *before* the currently set matrix. */
+    cairo_matrix_t old_matrix;
+    cairo_get_matrix(cr, &old_matrix);
+    cairo_set_matrix(cr, &viewport_matrix);
+    cairo_transform(cr, &old_matrix);
+}
+