add SvgWidget

README.md

@@ -11,6 +11,7 @@ Raven is a simple user interface library.
  - pango
  - pangocairo
  - xlib
+ - librsvg
 
 # Installing
 

meson.build

@@ -10,11 +10,13 @@ add_project_arguments('-g3',  language : 'cpp')
 cairomm_dep = dependency('cairomm-1.0')
 pangocairo_dep = dependency('pangocairo')
 xlib_dep = dependency('x11')
+librsvg_dep = dependency('librsvg-2.0')
 
 raven_dependencies = [
   cairomm_dep,
   xlib_dep,
-  pangocairo_dep
+  pangocairo_dep,
+  librsvg_dep
 ]
 
 headers = include_directories('src')
@@ -25,6 +27,7 @@ raven_source_files = [
   './src/Painter.cpp',
   './src/Window.cpp',
   './src/Widget.cpp',
+  './src/SvgWidget.cpp',
   './src/ScrollContainer.cpp',
   './src/Button.cpp',
   './src/DocumentLayout.cpp',
@@ -52,6 +55,7 @@ raven_header_files = [
   './src/ScrollContainer.hpp',
   './src/Styles.hpp',
   './src/Widget.hpp',
+  './src/SvgWidget.hpp',
   './src/Window.hpp'
 ]
 

src/SvgWidget.cpp

@@ -0,0 +1,59 @@
+#include "SvgWidget.hpp"
+#include "cairomm/context.h"
+#include "cairomm/enums.h"
+#include "cairomm/surface.h"
+
+namespace Raven {
+
+void SvgWidget::on_init() {
+    m_file = g_file_new_for_path(m_path.c_str());
+    m_handle = rsvg_handle_new_from_gfile_sync(m_file, RSVG_HANDLE_FLAGS_NONE, NULL, NULL);
+
+    set_style(&clear_widget_style);
+
+    if (!m_handle) {
+        std::cerr << "could not load svg file: " << m_path << std::endl;
+        exit(EXIT_FAILURE);
+    }
+
+    set_did_init(true);
+}
+
+void SvgWidget::on_after_layout() {
+    auto width = rect().width();
+    auto height = rect().height();
+
+    if (width == m_known_width && height == m_known_height) {
+        return;
+    }
+
+    m_known_width = width;
+    m_known_height = height;
+
+    RsvgRectangle viewport = {
+        .x = 0.0,
+        .y = 0.0,
+        .width = width,
+        .height = height,
+    };
+
+    m_image_surface = Cairo::ImageSurface::create(Cairo::Format::FORMAT_ARGB32, width, height);
+    m_image_context = Cairo::Context::create(m_image_surface);
+
+    rsvg_handle_render_document(m_handle, m_image_context->cobj(), &viewport, NULL);
+}
+
+void SvgWidget::on_paint() {
+    if (!m_image_surface)
+        return;
+
+    painter()->cairo()->set_source(m_image_surface, 0, 0);
+    painter()->cairo()->paint();
+}
+
+SvgWidget::~SvgWidget() {
+    g_object_unref(m_file);
+    g_object_unref(m_handle);
+}
+
+}

src/SvgWidget.hpp

@@ -0,0 +1,37 @@
+#pragma once
+
+#include <string>
+#include "cairomm/context.h"
+#include "cairomm/enums.h"
+#include "cairomm/refptr.h"
+#include "cairomm/surface.h"
+#include "raven/Widget.hpp"
+#include "librsvg/rsvg.h"
+
+namespace Raven {
+
+class SvgWidget : public Raven::Widget {
+public:
+    SvgWidget(std::string path)
+        : Raven::Widget()
+        , m_path(path) {}
+
+    ~SvgWidget();
+
+    std::string &path() { return m_path; }
+    void set_path(std::string path) { m_path = path; repaint(); }
+protected:
+    void on_init();
+    void on_after_layout();
+    void on_paint();
+private:
+    std::string m_path;
+    RsvgHandle *m_handle;
+    GFile *m_file;
+    Cairo::RefPtr<Cairo::Context> m_image_context;
+    Cairo::RefPtr<Cairo::ImageSurface> m_image_surface;
+    double m_known_width { 0.0 };
+    double m_known_height { 0.0 };
+};
+
+}