Support creating wxBitmapBundle from SVG in application resource

Allow creating wxBitmapBitmap from SVG image stored in an application
resource on the platforms where wxHAS_IMAGE_RESOURCES is defined.

On Windows, load the bundle from a resource with RT_RCDATA type and on
MacOS from a file with an extension "svg" placed in the "Resources"
subdirectory of the application bundle.

Closes #22061.

include/wx/bmpbndl.h

@@ -78,6 +78,12 @@ public:
 
     // Load SVG image from the given file (must be a local file, not an URL).
     static wxBitmapBundle FromSVGFile(const wxString& path, const wxSize& sizeDef);
+
+    // Create from SVG image stored as an application resource.
+    // On Windows, name must be a resource with RT_RCDATA type.
+    // On MacOS, name must be a file with an extension "svg" placed in the
+    // "Resources" subdirectory of the application bundle.
+    static wxBitmapBundle FromSVGResource(const wxString& name, const wxSize& sizeDef);
 #endif // wxHAS_SVG
 
     // Create from the resources: all existing versions of the bitmap of the

interface/wx/bmpbndl.h

@@ -76,6 +76,7 @@
     wxBITMAP_BUNDLE_2() macro which can avoid the need to check for
     wxHAS_IMAGE_RESOURCES explicitly in the code in a common case of having
     only 2 embedded resources (for standard and high DPI).
+    See also FromSVGResource().
 
     Also note that the existing code using wxBitmap is compatible with the
     functions taking wxBitmapBundle in wxWidgets 3.1.6 and later because
@@ -187,14 +188,16 @@ public:
         Create a bundle from the bitmaps in the application resources.
 
         This function can only be used on the platforms supporting storing
-        bitmaps in resources, and currently only works under MSW and simply
-        returns an empty bundle on the other platforms.
+        bitmaps in resources, and currently only works under MSW and MacOS
+        and returns an empty bundle on the other platforms.
 
         Under MSW, for this function to create a valid bundle, you must have @c
         RCDATA resource with the given @a name in your application resource
         file (with the extension @c .rc) containing PNG file, and any other
         resources using @a name as prefix and suffix with the scale, e.g. "_2x"
         or "_1_5x" (for 150% DPI) will be also loaded as part of the bundle.
+
+         @see FromSVGResource()
      */
     static wxBitmapBundle FromResources(const wxString& name);
 
@@ -261,6 +264,21 @@ public:
      */
     static wxBitmapBundle FromSVGFile(const wxString& path, const wxSize& sizeDef);
 
+    /**
+        Create a bundle from the SVG image loaded from an application resource.
+        Available only on the platforms supporting images in resources, i.e.,
+        MSW and MacOS.
+
+        @param name On MSW, it must be a resource with @c RT_RCDATA type.
+            On MacOS, it must be a file with an extension "svg" placed in
+            the "Resources" subdirectory of the application bundle.
+        @param sizeDef The default size to return from GetDefaultSize() for
+            this bundle.
+
+        @see FromResources(), FromSVGFile()
+     */
+    static wxBitmapBundle FromSVGResource(const wxString& name, const wxSize& sizeDef);
+
     /**
         Check if bitmap bundle is non-empty.
 

src/common/bmpbndl.cpp

@@ -358,7 +358,7 @@ wxBitmapBundle wxBitmapBundle::FromImpl(wxBitmapBundleImpl* impl)
 }
 
 
-// MSW has its own, actually working, version, in MSW-specific code.
+// MSW and MacOS have their own, actually working, version, in their platform-specific code.
 #if !defined( __WXMSW__ ) && !defined( __WXOSX__ )
 
 /* static */
@@ -374,6 +374,23 @@ wxBitmapBundle wxBitmapBundle::FromResources(const wxString& WXUNUSED(name))
     return wxBitmapBundle();
 }
 
+#ifdef wxHAS_SVG
+
+/* static */
+wxBitmapBundle wxBitmapBundle::FromSVGResource(const wxString& WXUNUSED(name), const wxSize& WXUNUSED(sizeDef))
+{
+    wxFAIL_MSG
+    (
+        "Loading an SVG from a resource not available on this platform, "
+        "don't use this function and call wxBitmapBundle::FromSVG(File)() "
+        "instead."
+    );
+
+    return wxBitmapBundle();
+}
+
+#endif // wxHAS_SVG
+
 #endif // !__WXMSW__ && !__WXOSX__
 
 wxBitmapBundle wxBitmapBundle::FromFiles(const wxString& filename)

src/msw/bmpbndl.cpp

@@ -18,9 +18,12 @@
 // for compilers that support precompilation, includes "wx.h".
 #include "wx/wxprec.h"
 
+#include "wx/utils.h"
+
 #ifndef WX_PRECOMP
     #include "wx/log.h"
 
+    #include "wx/msw/private.h"
     #include "wx/msw/wrapwin.h"
 #endif // WX_PRECOMP
 
@@ -352,3 +355,29 @@ wxBitmapBundle wxBitmapBundle::FromResources(const wxString& name)
 
     return wxBitmapBundle(new wxBitmapBundleImplRC(resourceInfos, bitmap));
 }
+
+#ifdef wxHAS_SVG
+
+/* static */
+wxBitmapBundle wxBitmapBundle::FromSVGResource(const wxString& name, const wxSize& sizeDef)
+{
+    // Currently we hardcode RCDATA resource type as this is what is usually
+    // used for the embedded images. We could allow specifying the type as part
+    // of the name in the future (e.g. "type:name" or something like this) if
+    // really needed.
+    wxCharBuffer svgData = wxCharBuffer::CreateOwned(wxLoadUserResource(name, RT_RCDATA, NULL, wxGetInstance()));
+
+    if ( !svgData.data() )
+    {
+        wxLogError(wxS("SVG image \"%s\" not found, check ")
+                   wxS("that the resource file contains \"RCDATA\" ")
+                   wxS("resource with this name."),
+                   name);
+
+        return wxBitmapBundle();
+    }
+
+    return wxBitmapBundle::FromSVG(svgData.data(), sizeDef);
+}
+
+#endif // wxHAS_SVG

src/osx/core/bmpbndl.mm

@@ -281,3 +281,10 @@ WXImage wxOSXGetImageFromBundle(const wxBitmapBundle& bundle)
 
     return image;
 }
+
+#ifdef wxHAS_SVG
+wxBitmapBundle wxBitmapBundle::FromSVGResource(const wxString& name, const wxSize &sizeDef)
+{
+    return wxBitmapBundle::FromSVGFile(wxFileName(wxStandardPaths::Get().GetResourcesDir(), name, "svg").GetFullPath(), sizeDef);
+}
+#endif // #ifdef wxHAS_SVG