add support for Apple Pencil and build for iOS

engine/node_panel_brush.cpp

@@ -3,6 +3,10 @@
 #include "node_panel_brush.h"
 #include "asset.h"
 
+#ifdef __APPLE__
+#include <Foundation/Foundation.h>
+#endif
+
 Node* NodeButtonBrush::clone_instantiate() const
 {
     return new NodeButtonBrush();
@@ -99,9 +103,13 @@ std::vector<std::string> NodePanelBrush::FindAllBrushes(std::string folder)
     }
     AAssetDir_close(dir);
 #else
+    NSString* bundle_path = [[NSBundle mainBundle] resourcePath];
+    std::string base = [bundle_path cStringUsingEncoding:1];
+    std::string abs_path = base + "/" + folder;
+
     DIR *dp;
     struct dirent *ep;
-    dp = opendir(folder.c_str());
+    dp = opendir(abs_path.c_str());
 
     if (dp != NULL)
     {