Creates an RTImage cache

Fixes:
- Fixes GUI issue on Windows (GDI handles limit reached)
- Fixes an incorrect icon name in Perspective tool
- Adds robustness RTScalable::loadSurfaceFromIcon function

rtgui/perspective.cc

@@ -120,7 +120,7 @@ PerspCorrection::PerspCorrection () : FoldableToolPanel(this, "perspective", M("
     RTImage* const ipersVL = Gtk::manage (new RTImage ("perspective-vertical-bottom-small"));
     RTImage* const ipersVR = Gtk::manage (new RTImage ("perspective-vertical-top-small"));
 
-    RTImage* const ipers_auto_pitch = Gtk::manage (new RTImage ("perspective-vertical-botton", Gtk::ICON_SIZE_BUTTON));
+    RTImage* const ipers_auto_pitch = Gtk::manage (new RTImage ("perspective-vertical-bottom", Gtk::ICON_SIZE_BUTTON));
     RTImage* const ipers_auto_yaw = Gtk::manage (new RTImage ("perspective-horizontal-left", Gtk::ICON_SIZE_BUTTON));
     RTImage* const ipers_auto_pitch_yaw = Gtk::manage (new RTImage ("perspective-horizontal-vertical", Gtk::ICON_SIZE_BUTTON));
 

rtgui/rtimage.cc

@@ -21,21 +21,95 @@
 
 #include "rtimage.h"
 
+#include "rtsurface.h"
+
+std::map<std::pair<Glib::ustring, Gtk::IconSize>, std::shared_ptr<RTSurface>> RTImageCache::cache;
+
+std::shared_ptr<RTSurface> RTImageCache::getCachedSurface(const Glib::ustring &icon_name, const Gtk::IconSize icon_size)
+{
+    // Look for an existing cached icon
+    const auto key = std::pair<Glib::ustring, Gtk::IconSize>(icon_name, icon_size);
+    const auto item = cache.find(key);
+
+    if (item != cache.end()) { // A cached icon exists
+        return item->second;
+    } else { // Create the icon
+        auto surface = std::shared_ptr<RTSurface>(new RTSurface(icon_name, icon_size));
+
+        // Add the surface to the cache if the icon exist
+        if (surface) {
+            cache.insert({key, surface});
+        }
+
+        return surface;
+    }
+}
+
+void RTImageCache::updateCache()
+{
+    // Iterate over cache to updated RTSurface
+    for (auto const& item : cache) {
+        item.second->updateSurface();
+    }
+}
+
 RTImage::RTImage () {}
 
 RTImage::RTImage (const Glib::ustring& iconName, const Gtk::IconSize iconSize) :
-    Gtk::Image(iconName, iconSize),
+    Gtk::Image(),
-    size(iconSize)
+    size(iconSize),
+    icon_name(iconName)
 {
+    // Set surface from icon cache
+    surface = RTImageCache::getCachedSurface(this->icon_name, this->size);
+
+    // Add it to the RTImage if surface exists
+    if (surface) {
+        set(surface->get());
+    }
 }
 
 void RTImage::set_from_icon_name(const Glib::ustring& iconName)
 {
-    Gtk::Image::set_from_icon_name(iconName, this->size);
+    this->icon_name = iconName;
+
+    // Set surface from icon cache
+    surface = RTImageCache::getCachedSurface(this->icon_name, this->size);
+
+    // Add it to the RTImage if surface exists
+    if (surface) {
+        set(surface->get());
+    }
 }
 
 void RTImage::set_from_icon_name(const Glib::ustring& iconName, const Gtk::IconSize iconSize)
 {
+    this->icon_name = iconName;
     this->size = iconSize;
-    Gtk::Image::set_from_icon_name(iconName, this->size);
+
+    // Set surface from icon cache
+    surface = RTImageCache::getCachedSurface(this->icon_name, this->size);
+
+    // Add it to the RTImage if surface exists
+    if (surface) {
+        set(surface->get());
+    }
+}
+
+int RTImage::get_width()
+{
+    if (surface) {
+        return surface->getWidth();
+    }
+
+    return -1;
+}
+
+int RTImage::get_height()
+{
+    if (surface) {
+        return surface->getHeight();
+    }
+
+    return -1;
 }

rtgui/rtimage.h

@@ -20,7 +20,18 @@
  */
 #pragma once
 
-#include <gtkmm/image.h>
+#include <gtkmm.h>
+
+class RTSurface;
+class RTImageCache final
+{
+private:
+    static std::map<std::pair<Glib::ustring, Gtk::IconSize>, std::shared_ptr<RTSurface>> cache;
+
+public:
+    static std::shared_ptr<RTSurface> getCachedSurface(const Glib::ustring &icon_name, const Gtk::IconSize icon_size);
+    static void updateCache();
+};
 
 /**
  * @brief A derived class of Gtk::Image in order to handle theme-related icon sets.
@@ -29,6 +40,8 @@ class RTImage final : public Gtk::Image
 {
 private:
     Gtk::IconSize size;
+    Glib::ustring icon_name;
+    std::shared_ptr<RTSurface> surface;
 
 public:
     RTImage ();
@@ -36,4 +49,7 @@ public:
 
     void set_from_icon_name(const Glib::ustring& iconName);
     void set_from_icon_name(const Glib::ustring& iconName, const Gtk::IconSize iconSize);
+
+    int get_width();
+    int get_height();
 };

rtgui/rtscalable.cc

@@ -68,10 +68,22 @@ Cairo::RefPtr<Cairo::ImageSurface> RTScalable::loadSurfaceFromIcon(const Glib::u
 
     // Looking for corresponding icon (if existing)
     const auto iconInfo = theme->lookup_icon(iconName, size);
+
+    if (!iconInfo) {
+        if (rtengine::settings->verbose) {
+            std::cerr << "Failed to load icon \"" << iconName << "\" for size " << size << "px" << std::endl;
+        }
+
+        return surf;
+    }
+
     const auto iconPath = iconInfo.get_filename();
 
-    if ((iconPath.empty() || !iconInfo) && rtengine::settings->verbose) {
+    if (iconPath.empty()) {
-        std::cerr << "Failed to load icon \"" << iconName << "\" for size " << size << "px" << std::endl;
+        if (rtengine::settings->verbose) {
+            std::cerr << "Failed to load icon \"" << iconName << "\" for size " << size << "px" << std::endl;
+        }
+
         return surf;
     }
 

rtgui/rtsurface.cc

@@ -161,19 +161,7 @@ Cairo::RefPtr<Cairo::ImageSurface> RTSurface::get()
 {
     if (dpiBack != RTScalable::getDPI() ||
         scaleBack != RTScalable::getScale()) {
-            switch (type) {
+            updateSurface();
-                case RTSurface::IconType :
-                    surface = RTScalable::loadSurfaceFromIcon(name, icon_size);
-                    break;
-                case RTSurface::PNGType :
-                    surface = RTScalable::loadSurfaceFromPNG(name);
-                    break;
-                case RTSurface::SVGType :
-                    surface = RTScalable::loadSurfaceFromSVG(name);
-                    break;
-                default :
-                    break;
-            }
 
             // Save new DPI and scale
             dpiBack = RTScalable::getDPI();
@@ -182,3 +170,21 @@ Cairo::RefPtr<Cairo::ImageSurface> RTSurface::get()
 
     return surface;
 }
+
+void RTSurface::updateSurface()
+{
+    // Update surface based on the scale
+    switch (type) {
+        case RTSurface::IconType :
+            surface = RTScalable::loadSurfaceFromIcon(name, icon_size);
+            break;
+        case RTSurface::PNGType :
+            surface = RTScalable::loadSurfaceFromPNG(name);
+            break;
+        case RTSurface::SVGType :
+            surface = RTScalable::loadSurfaceFromSVG(name);
+            break;
+        default :
+            break;
+    }
+}

rtgui/rtsurface.h

@@ -52,4 +52,5 @@ public:
     bool hasSurface();
 
     Cairo::RefPtr<Cairo::ImageSurface> get();
+    void updateSurface();
 };