1 files changed, 112 insertions, 0 deletions
diff --git a/src/ui/svg-renderer.cpp b/src/ui/svg-renderer.cpp
new file mode 100644
index 0000000..e8901d5
--- /dev/null
+++ b/src/ui/svg-renderer.cpp
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/**
+ * SVG to Pixbuf renderer
+ *
+ * Author:
+ *   Michael Kowalski
+ *
+ * Copyright (C) 2020-2021 Michael Kowalski
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include "svg-renderer.h"
+#include "io/file.h"
+#include "xml/repr.h"
+#include "object/sp-root.h"
+#include "display/cairo-utils.h"
+#include "helper/pixbuf-ops.h"
+#include "util/units.h"
+
+namespace Inkscape {
+
+Glib::ustring rgba_to_css_color(double r, double g, double b) {
+    char buffer[16];
+    sprintf(buffer, "#%02x%02x%02x",
+        static_cast<int>(r * 0xff + 0.5),
+        static_cast<int>(g * 0xff + 0.5),
+        static_cast<int>(b * 0xff + 0.5)
+    );
+    return Glib::ustring(buffer);
+}
+
+Glib::ustring rgba_to_css_color(const Gdk::RGBA& color) {
+    return rgba_to_css_color(color.get_red(), color.get_green(), color.get_blue());
+}
+
+Glib::ustring rgba_to_css_color(const SPColor& color) {
+    float rgb[3];
+    color.get_rgb_floatv(rgb);
+    return rgba_to_css_color(rgb[0], rgb[1], rgb[2]);
+}
+
+Glib::ustring double_to_css_value(double value) {
+    char buffer[32];
+    // arbitrarily chosen precision
+    sprintf(buffer, "%.4f", value);
+    return Glib::ustring(buffer);
+}
+
+svg_renderer::svg_renderer(const char* svg_file_path) {
+
+    auto file = Gio::File::create_for_path(svg_file_path);
+
+    _document.reset(ink_file_open(file, nullptr));
+
+    if (_document) {
+        _root = _document->getRoot();
+    }
+
+    if (!_root) throw std::runtime_error("Cannot find root element in svg document");
+}
+
+size_t svg_renderer::set_style(const Glib::ustring& selector, const char* name, const Glib::ustring& value) {
+    auto objects = _document->getObjectsBySelector(selector);
+    for (auto el : objects) {
+        if (SPCSSAttr* css = sp_repr_css_attr(el->getRepr(), "style")) {
+            sp_repr_css_set_property(css, name, value.c_str());
+            el->changeCSS(css, "style");
+            sp_repr_css_attr_unref(css);
+        }
+    }
+    return objects.size();
+}
+
+double svg_renderer::get_width_px() const {
+    return _document->getWidth().value("px");
+}
+
+double svg_renderer::get_height_px() const {
+    return _document->getHeight().value("px");
+}
+
+Inkscape::Pixbuf* svg_renderer::do_render(double scale) {
+    auto w = _document->getWidth().value("px");
+    auto h = _document->getHeight().value("px");
+    auto dpi = 96 * scale;
+    auto area = Geom::Rect(0, 0, w, h);
+
+    return sp_generate_internal_bitmap(_document.get(), area, dpi);
+}
+
+Glib::RefPtr<Gdk::Pixbuf> svg_renderer::render(double scale) {
+    auto pixbuf = do_render(scale);
+    if (!pixbuf) return Glib::RefPtr<Gdk::Pixbuf>();
+
+    // ref it
+    auto raw = Glib::wrap(pixbuf->getPixbufRaw(), true);
+    delete pixbuf;
+    return raw;
+}
+
+Cairo::RefPtr<Cairo::Surface> svg_renderer::render_surface(double scale) {
+    auto pixbuf = do_render(scale);
+    if (!pixbuf) return Cairo::RefPtr<Cairo::Surface>();
+
+    // ref it by saying that we have no reference
+    auto surface = Cairo::RefPtr<Cairo::Surface>(new Cairo::Surface(pixbuf->getSurfaceRaw(), false));
+    delete pixbuf;
+    return surface;
+}
+
+} // namespace