diff --git a/src/dlangui/graphics/drawbuf.d b/src/dlangui/graphics/drawbuf.d
index 93dcf362..cd70b355 100644
--- a/src/dlangui/graphics/drawbuf.d
+++ b/src/dlangui/graphics/drawbuf.d
@@ -18,9 +18,13 @@ uint blendARGB(uint dst, uint src, uint alpha) {
 
 class DrawBuf : RefCountedObject {
     protected Rect _clipRect;
+    /// returns current width
     @property int width() { return 0; }
+    /// returns current height
     @property int height() { return 0; }
+    /// returns clipping rectangle, when clipRect.isEmpty == true -- means no clipping.
     @property ref Rect clipRect() { return _clipRect; }
+    /// sets new clipping rectangle, when clipRect.isEmpty == true -- means no clipping.
     @property void clipRect(const ref Rect rect) { 
         _clipRect = rect; 
         _clipRect.intersect(Rect(0, 0, width, height));
@@ -40,6 +44,9 @@ class DrawBuf : RefCountedObject {
     }
     void beforeDrawing() { }
     void afterDrawing() { }
+    /// returns buffer bits per pixel
+    @property int bpp() { return 0; }
+    /// returns pointer to ARGB scanline, null if y is out of range or buffer doesn't provide access to its memory
     uint * scanLine(int y) { return null; }
     abstract void resize(int width, int height);
     abstract void fill(uint color);
@@ -52,9 +59,13 @@ class DrawBuf : RefCountedObject {
     ~this() { clear(); }
 }
 
+alias DrawBufRef = Ref!DrawBuf;
+
 class ColorDrawBufBase : DrawBuf {
     int _dx;
     int _dy;
+    /// returns buffer bits per pixel
+    override @property int bpp() { return 32; }
     @property override int width() { return _dx; }
     @property override int height() { return _dy; }
     override void fillRect(int left, int top, int right, int bottom, uint color) {
diff --git a/src/dlangui/graphics/fonts.d b/src/dlangui/graphics/fonts.d
index 3ffa8351..3730595b 100644
--- a/src/dlangui/graphics/fonts.d
+++ b/src/dlangui/graphics/fonts.d
@@ -1,17 +1,17 @@
-module dlangui.graphics.fonts;
-public import dlangui.graphics.drawbuf;
-public import dlangui.core.types;
-public import dlangui.core.logger;
-import std.algorithm;
-
-enum FontFamily : int {
-    SansSerif,
-    Serif,
-	Fantasy,
-	Cursive,
-    MonoSpace
-}
-
+module dlangui.graphics.fonts;
+public import dlangui.graphics.drawbuf;
+public import dlangui.core.types;
+public import dlangui.core.logger;
+import std.algorithm;
+
+enum FontFamily : int {
+    SansSerif,
+    Serif,
+	Fantasy,
+	Cursive,
+    MonoSpace
+}
+
 struct Glyph
 {
     ubyte   blackBoxX;   ///< 0: width of glyph
@@ -82,101 +82,101 @@ struct GlyphCache
 		clear();
 	}
 }
-
-class Font : RefCountedObject {
-    abstract @property int size();
-    abstract @property int height();
-    abstract @property int weight();
-    abstract @property int baseline();
-    abstract @property bool italic();
-    abstract @property string face();
-    abstract @property FontFamily family();
-    abstract @property bool isNull();
-	// measure text string, return accumulated widths[] (distance to end of n-th character), returns number of measured chars.
-	abstract int measureText(const dchar[] text, ref int[] widths, int maxWidth);
-	// draw text string to buffer
-	abstract void drawText(DrawBuf buf, int x, int y, const dchar[] text, uint color);
-	abstract Glyph * getCharGlyph(dchar ch);
-
+
+class Font : RefCountedObject {
+    abstract @property int size();
+    abstract @property int height();
+    abstract @property int weight();
+    abstract @property int baseline();
+    abstract @property bool italic();
+    abstract @property string face();
+    abstract @property FontFamily family();
+    abstract @property bool isNull();
+	// measure text string, return accumulated widths[] (distance to end of n-th character), returns number of measured chars.
+	abstract int measureText(const dchar[] text, ref int[] widths, int maxWidth);
+	// draw text string to buffer
+	abstract void drawText(DrawBuf buf, int x, int y, const dchar[] text, uint color);
+	abstract Glyph * getCharGlyph(dchar ch);
+
 	// clear usage flags for all entries
 	abstract void checkpoint();
 	// removes entries not used after last call of checkpoint() or cleanup()
 	abstract void cleanup();
-
-    void clear() {}
-
-    ~this() { clear(); }
-}
-alias FontRef = Ref!Font;
-
-struct FontList {
-	FontRef[] _list;
-	uint _len;
-	~this() {
-		for (uint i = 0; i < _len; i++) {
-			_list[i].clear();
-		}
-	}
-	// returns item by index
-	ref FontRef get(int index) {
-		return _list[index];
-	}
-	// returns index of found item, -1 if not found
-	int find(int size, int weight, bool italic, FontFamily family, string face) {
-		for (int i = 0; i < _len; i++) {
-			Font item = _list[i].get;
-			if (item.family != family)
-				continue;
-			if (item.size != size)
-				continue;
-			if (item.italic != italic || item.weight != weight)
-				continue;
-			if (!equal(item.face, face))
-				continue;
-			return i;
-		}
-		return -1;
-	}
-	ref FontRef add(Font item) {
-		Log.d("FontList.add() enter");
-		if (_len >= _list.length) {
-			_list.length = _len < 16 ? 16 : _list.length * 2;
-		}
-		_list[_len++] = item;
-		Log.d("FontList.add() exit");
-		return _list[_len - 1];
-	}
-	// remove unused items - with reference == 1
-	void cleanup() {
-		for (int i = 0; i < _len; i++)
-			if (_list[i].refCount <= 1)
-				_list[i].clear();
-		int dst = 0;
-		for (int i = 0; i < _len; i++) {
-			if (!_list[i].isNull)
-				if (i != dst)
-					_list[dst++] = _list[i];
-		}
-		_len = dst;
-		for (int i = 0; i < _len; i++)
-			_list[i].cleanup();
-	}
-	void checkpoint() {
-		for (int i = 0; i < _len; i++)
-			_list[i].checkpoint();
-	}
-}
-
-class FontManager {
-    static __gshared FontManager _instance;
-    static @property void instance(FontManager manager) {
-        _instance = manager;
-    }
-    static @property FontManager instance() {
-        return _instance;
-    }
-
-    abstract ref FontRef getFont(int size, int weight, bool italic, FontFamily family, string face);
+
+    void clear() {}
+
+    ~this() { clear(); }
+}
+alias FontRef = Ref!Font;
+
+struct FontList {
+	FontRef[] _list;
+	uint _len;
+	~this() {
+		for (uint i = 0; i < _len; i++) {
+			_list[i].clear();
+		}
+	}
+	// returns item by index
+	ref FontRef get(int index) {
+		return _list[index];
+	}
+	// returns index of found item, -1 if not found
+	int find(int size, int weight, bool italic, FontFamily family, string face) {
+		for (int i = 0; i < _len; i++) {
+			Font item = _list[i].get;
+			if (item.family != family)
+				continue;
+			if (item.size != size)
+				continue;
+			if (item.italic != italic || item.weight != weight)
+				continue;
+			if (!equal(item.face, face))
+				continue;
+			return i;
+		}
+		return -1;
+	}
+	ref FontRef add(Font item) {
+		Log.d("FontList.add() enter");
+		if (_len >= _list.length) {
+			_list.length = _len < 16 ? 16 : _list.length * 2;
+		}
+		_list[_len++] = item;
+		Log.d("FontList.add() exit");
+		return _list[_len - 1];
+	}
+	// remove unused items - with reference == 1
+	void cleanup() {
+		for (int i = 0; i < _len; i++)
+			if (_list[i].refCount <= 1)
+				_list[i].clear();
+		int dst = 0;
+		for (int i = 0; i < _len; i++) {
+			if (!_list[i].isNull)
+				if (i != dst)
+					_list[dst++] = _list[i];
+		}
+		_len = dst;
+		for (int i = 0; i < _len; i++)
+			_list[i].cleanup();
+	}
+	void checkpoint() {
+		for (int i = 0; i < _len; i++)
+			_list[i].checkpoint();
+	}
+}
+
+class FontManager {
+    static __gshared FontManager _instance;
+    static @property void instance(FontManager manager) {
+        _instance = manager;
+    }
+    static @property FontManager instance() {
+        return _instance;
+    }
+
+    abstract ref FontRef getFont(int size, int weight, bool italic, FontFamily family, string face);
 
 	// clear usage flags for all entries
 	abstract void checkpoint();
@@ -184,5 +184,5 @@ class FontManager {
 	// removes entries not used after last call of checkpoint() or cleanup()
 	abstract void cleanup();
 
-	~this() {}
-}
+	~this() {}
+}
diff --git a/src/dlangui/graphics/images.d b/src/dlangui/graphics/images.d
index 37d5ef80..c4c2e6ca 100644
--- a/src/dlangui/graphics/images.d
+++ b/src/dlangui/graphics/images.d
@@ -3,7 +3,77 @@ module dlangui.graphics.images;
 import dlangui.graphics.drawbuf;
 import std.stream;
 import libpng.png;
-import core.sys.posix.setjmp;
+
+/// decoded image cache
+class ImageCache {
+
+    static class ImageCacheItem {
+        string _filename;
+        DrawBufRef _drawbuf;
+        bool _error; // flag to avoid loading of file if it has been failed once
+        bool _used;
+        this(string filename) {
+            _filename = filename;
+        }
+        @property ref DrawBufRef get() {
+            if (!_drawbuf.isNull || _error) {
+                _used = true;
+                return _drawbuf;
+            }
+            _drawbuf = loadImage(_filename);
+            _used = true;
+            if (_drawbuf.isNull)
+                _error = true;
+            return _drawbuf;
+        }
+        /// remove from memory, will cause reload on next access
+        void compact() {
+            if (!_drawbuf.isNull)
+                _drawbuf.clear();
+        }
+        /// mark as not used
+        void checkpoint() {
+            _used = false;
+        }
+        /// cleanup if unused since last checkpoint
+        void cleanup() {
+            if (!_used)
+                compact();
+        }
+    }
+    ImageCacheItem[string] _map;
+
+    /// get and cache image
+    ref DrawBufRef get(string filename) {
+        if (filename in _map) {
+            return _map[filename].get;
+        }
+        ImageCacheItem item = new ImageCacheItem(filename);
+        _map[filename] = item;
+        return item.get;
+    }
+	// clear usage flags for all entries
+	void checkpoint() {
+        foreach (item; _map)
+            item.checkpoint();
+    }
+	// removes entries not used after last call of checkpoint() or cleanup()
+	void cleanup() {
+        foreach (item; _map)
+            item.cleanup();
+    }
+}
+
+/// load and decode image from file to ColorDrawBuf, returns null if loading or decoding is failed
+ColorDrawBuf loadImage(string filename) {
+    try {
+        std.stream.File f = new std.stream.File(filename);
+	    scope(exit) { f.close(); }
+        return loadImage(f);
+    } catch (Exception e) {
+        return null;
+    }
+}
 
 /// load and decode image from stream to ColorDrawBuf, returns null if loading or decoding is failed
 ColorDrawBuf loadImage(InputStream stream) {
@@ -37,6 +107,7 @@ extern (C) void lvpng_read_func(png_structp png, png_bytep buf, png_size_t len)
         throw new ImageDecodingException("Error while reading PNG image");
 }
 
+/// load and decode PNG image
 ColorDrawBuf loadPngImage(InputStream stream)
 {
     png_structp png_ptr = null;