diff --git a/src/data/field/choice.cpp b/src/data/field/choice.cpp
index 9ed4f313..71fe6ba0 100644
--- a/src/data/field/choice.cpp
+++ b/src/data/field/choice.cpp
@@ -214,11 +214,8 @@ void ChoiceStyle::initImage() {
 int ChoiceStyle::update(Context& ctx) {
 	// Don't update the choice images, leave that to invalidate()
 	int change = Style       ::update(ctx)
-	           | font         .update(ctx) * CHANGE_OTHER;
-	if (mask_filename.update(ctx)) {
-		change |= CHANGE_MASK;
-		mask = Image();
-	}
+	           | font         .update(ctx) * CHANGE_OTHER
+	           | mask         .update(ctx) * CHANGE_MASK;
 	if (!choice_images_initialized) {
 		// we only want to do this once because it is rather slow, other updates are handled by dependencies
 		choice_images_initialized = true;
@@ -255,13 +252,6 @@ void ChoiceStyle::invalidate() {
 	tellListeners(CHANGE_OTHER);
 }
 
-void ChoiceStyle::loadMask(Package& pkg) {
-	if (mask.Ok() || mask_filename().empty()) return;
-	// load file
-	InputStreamP image_file = pkg.openIn(mask_filename);
-	mask.LoadFile(*image_file);
-}
-
 IMPLEMENT_REFLECTION_ENUM(ChoicePopupStyle) {
 	VALUE_N("dropdown",	POPUP_DROPDOWN);
 	VALUE_N("menu",		POPUP_MENU);
@@ -293,7 +283,7 @@ IMPLEMENT_REFLECTION(ChoiceStyle) {
 	REFLECT_BASE(Style);
 	REFLECT(popup_style);
 	REFLECT(render_style);
-	REFLECT_N("mask",mask_filename);
+	REFLECT(mask);
 	REFLECT(combine);
 	REFLECT(alignment);
 	REFLECT(font);
diff --git a/src/data/field/choice.hpp b/src/data/field/choice.hpp
index b8299b3f..1b5bc007 100644
--- a/src/data/field/choice.hpp
+++ b/src/data/field/choice.hpp
@@ -143,20 +143,17 @@ class ChoiceStyle : public Style {
 	ChoicePopupStyle            popup_style;        ///< Style of popups/menus
 	ChoiceRenderStyle           render_style;       ///< Style of rendering
 	Font                        font;               ///< Font for drawing text (when RENDER_TEXT)
-	CachedScriptableImage       image;				///< Image to draw (when RENDER_IMAGE)
+	CachedScriptableImage       image;              ///< Image to draw (when RENDER_IMAGE)
 	map<String,ScriptableImage> choice_images;      ///< Images for the various choices (when RENDER_IMAGE)
 	bool                        choice_images_initialized;
-	Scriptable<String>          mask_filename;      ///< Filename of an additional mask over the images
+	CachedScriptableMask        mask;               ///< Mask image
 	ImageCombine                combine;            ///< Combining mode for drawing the images
 	Alignment                   alignment;          ///< Alignment of images
-	Image                       mask;               ///< The actual mask image
 	wxImageList*                thumbnails;         ///< Thumbnails for the choices
-	vector<ThumbnailStatus>     thumbnails_status;	///< Which thumbnails are up to date?
+	vector<ThumbnailStatus>     thumbnails_status;  ///< Which thumbnails are up to date?
 	// information from image rendering
 	double content_width, content_height;		///< Size of the rendered image/text
 	
-	/// Load the mask image, if it's not already done
-	void loadMask(Package& pkg);
 	/// Initialize image from choice_images
 	void initImage();
 	
diff --git a/src/data/field/color.cpp b/src/data/field/color.cpp
index b17b9386..c916cd1b 100644
--- a/src/data/field/color.cpp
+++ b/src/data/field/color.cpp
@@ -62,13 +62,13 @@ IMPLEMENT_REFLECTION(ColorStyle) {
 	REFLECT(right_width);
 	REFLECT(top_width);
 	REFLECT(bottom_width);
-	REFLECT_N("mask", mask_filename);
+	REFLECT(mask);
 	REFLECT(combine);
 }
 
 int ColorStyle::update(Context& ctx) {
-	return Style       ::update(ctx)
-	     | mask_filename.update(ctx) * CHANGE_MASK;
+	return Style::update(ctx)
+	     | mask.update(ctx) * CHANGE_MASK;
 }
 
 // ----------------------------------------------------------------------------- : ColorValue
diff --git a/src/data/field/color.hpp b/src/data/field/color.hpp
index 37942fde..bf0244e7 100644
--- a/src/data/field/color.hpp
+++ b/src/data/field/color.hpp
@@ -13,6 +13,7 @@
 #include <util/defaultable.hpp>
 #include <data/field.hpp>
 #include <script/scriptable.hpp>
+#include <script/image.hpp>
 
 // ----------------------------------------------------------------------------- : ColorField
 
@@ -56,13 +57,13 @@ class ColorStyle : public Style {
 	ColorStyle(const ColorFieldP& field);
 	DECLARE_STYLE_TYPE(Color);
 	
-	double             radius;          ///< Radius of round corners
-	double             left_width;      ///< Width of the colored region on the left side
-	double             right_width;     ///< Width of the colored region on the right side
-	double             top_width;       ///< Width of the colored region on the top side
-	double             bottom_width;    ///< Width of the colored region on the bottom side
-	Scriptable<String> mask_filename;   ///< Filename of an additional mask over the images
-	ImageCombine       combine;         ///< How to combine image with the background
+	double               radius;          ///< Radius of round corners
+	double               left_width;      ///< Width of the colored region on the left side
+	double               right_width;     ///< Width of the colored region on the right side
+	double               top_width;       ///< Width of the colored region on the top side
+	double               bottom_width;    ///< Width of the colored region on the bottom side
+	CachedScriptableMask mask;            ///< Mask image
+	ImageCombine         combine;         ///< How to combine image with the background
 	
 	virtual int update(Context&);
 };
diff --git a/src/data/field/image.cpp b/src/data/field/image.cpp
index 33ff2cec..d598b9a9 100644
--- a/src/data/field/image.cpp
+++ b/src/data/field/image.cpp
@@ -23,13 +23,13 @@ IMPLEMENT_REFLECTION(ImageField) {
 
 IMPLEMENT_REFLECTION(ImageStyle) {
 	REFLECT_BASE(Style);
-	REFLECT_N("mask", mask_filename);
+	REFLECT(mask);
 	REFLECT_N("default", default_image);
 }
 
 int ImageStyle::update(Context& ctx) {
 	return Style       ::update(ctx)
-	     | mask_filename.update(ctx) * CHANGE_MASK
+	     | mask         .update(ctx) * CHANGE_MASK
 	     | default_image.update(ctx) * CHANGE_DEFAULT;
 }
 
diff --git a/src/data/field/image.hpp b/src/data/field/image.hpp
index 9595549f..4c5c0029 100644
--- a/src/data/field/image.hpp
+++ b/src/data/field/image.hpp
@@ -35,8 +35,8 @@ class ImageStyle : public Style {
 	inline ImageStyle(const ImageFieldP& field) : Style(field) {}
 	DECLARE_STYLE_TYPE(Image);
 	
-	Scriptable<String> mask_filename; ///< Filename for a mask image
-	ScriptableImage    default_image; ///< Placeholder
+	CachedScriptableMask mask;          ///< Mask image
+	ScriptableImage      default_image; ///< Placeholder
 	
 	virtual int update(Context&);
 };
diff --git a/src/gfx/generated_image.hpp b/src/gfx/generated_image.hpp
index 36b48174..9c9a5309 100644
--- a/src/gfx/generated_image.hpp
+++ b/src/gfx/generated_image.hpp
@@ -35,7 +35,7 @@ class GeneratedImage : public ScriptValue {
 		
 		mutable int    width, height;	///< Width to force the image to, or 0 to keep the width of the input
 										///< In that case, width and height will be later set to the actual size
-		double         zoom;            ///< Zoom factor to use, when witdth=height=0
+		double         zoom;            ///< Zoom factor to use, when width=height=0
 		int            angle;           ///< Angle to rotate image by afterwards
 		PreserveAspect preserve_aspect;
 		bool           saturate;
@@ -55,9 +55,10 @@ class GeneratedImage : public ScriptValue {
 	
 	/// Can this image be generated safely from another thread?
 	virtual bool threadSafe() const { return true; }
-	
 	/// Is this image specific to the set (the local_package)?
 	virtual bool local() const { return false; }
+	/// Is this image blank?
+	virtual bool isBlank() const { return false; }
 	
 	virtual ScriptType type() const;
 	virtual String typeName() const;
@@ -88,6 +89,7 @@ class BlankImage : public GeneratedImage {
   public:
 	virtual Image generate(const Options&) const;
 	virtual bool operator == (const GeneratedImage& that) const;
+	virtual bool isBlank() const { return true; }
 	
 	// Why is this not thread safe? What is GTK smoking?
 	#ifdef __WXGTK__
diff --git a/src/gfx/gfx.hpp b/src/gfx/gfx.hpp
index acd7d95b..fcd3416f 100644
--- a/src/gfx/gfx.hpp
+++ b/src/gfx/gfx.hpp
@@ -167,8 +167,9 @@ class AlphaMask : public IntrusivePtrBase<AlphaMask> {
 	/// Apply the alpha mask to a bitmap
 	void setAlpha(Bitmap& b) const;
 	
-	/// Is the given location fully transparent?
-	bool isTransparent(int x, int y) const;
+	/// Is the given location opaque (not fully transparent)? when the mask were stretched to size
+	bool isOpaque(const RealPoint& p, const RealSize& size) const;
+	bool isOpaque(int x, int y) const;
 	
 	/// Determine a convex hull polygon *around* the mask
 	void convexHull(vector<wxPoint>& points) const;
@@ -178,9 +179,9 @@ class AlphaMask : public IntrusivePtrBase<AlphaMask> {
 	
 	/// Returns the start of a row, when the mask were stretched to size
 	/** This is: the x coordinate of the first non-transparent pixel */
-	double rowLeft (double y, RealSize size) const;
+	double rowLeft (double y, const RealSize& size) const;
 	/// Returns the end of a row, when the mask were stretched to size
-	double rowRight(double y, RealSize size) const;
+	double rowRight(double y, const RealSize& size) const;
 	
 	/// Does this mask have the given size?
 	inline bool hasSize(const wxSize& compare_size) const { return size == compare_size; }
diff --git a/src/gfx/mask_image.cpp b/src/gfx/mask_image.cpp
index 38710c95..d8f04e7c 100644
--- a/src/gfx/mask_image.cpp
+++ b/src/gfx/mask_image.cpp
@@ -17,9 +17,13 @@ AlphaMask::AlphaMask(const Image& img) : alpha(nullptr), lefts(nullptr), rights(
 	load(img);
 }
 AlphaMask::~AlphaMask() {
-	delete[] alpha;
-	delete[] lefts;
-	delete[] rights;
+	clear();
+}
+
+void AlphaMask::clear() {
+	delete[] alpha;  alpha  = nullptr;
+	delete[] lefts;  lefts  = nullptr;
+	delete[] rights; rights = nullptr;
 }
 
 void AlphaMask::load(const Image& img) {
@@ -54,10 +58,14 @@ void AlphaMask::setAlpha(Bitmap& bmp) const {
 	bmp = Bitmap(img);
 }
 
-bool AlphaMask::isTransparent(int x, int y) const {
+bool AlphaMask::isOpaque(int x, int y) const {
 	if (x < 0 || y < 0 || x >= size.x || y >= size.y) return false;
 	if (!alpha) return true;
-	return alpha[x + y * size.x] < 20;
+	return alpha[x + y * size.x] >= 20;
+}
+bool AlphaMask::isOpaque(const RealPoint& p, const RealSize& resize) const {
+	return isOpaque((int)(p.x * size.x / resize.width)
+	               ,(int)(p.y * size.y / resize.height));
 }
 
 /// Do the points form a (counter??)clockwise angle?
@@ -72,6 +80,10 @@ void make_convex(vector<wxPoint>& points) {
 		points.erase(points.end() - 2);
 	}
 }
+void add_convex_point(vector<wxPoint>& points, int x, int y) {
+	points.push_back(wxPoint(x,y));
+	make_convex(points);
+}
 
 void AlphaMask::convexHull(vector<wxPoint>& points) const {
 	if (!alpha) throw InternalError(_("AlphaMask::convexHull"));
@@ -84,36 +96,31 @@ void AlphaMask::convexHull(vector<wxPoint>& points) const {
 				miny = min(miny,y);
 				maxy = y;
 				if (y == miny) {
-					points.push_back(wxPoint(x-1,y-1));
+					add_convex_point(points, x-1, y-1);
 				}
-				points.push_back(wxPoint(x-1,y));
-				make_convex(points);
+				add_convex_point(points, x-1, y);
 				lastx = x;
 				break;
 			}
 		}
 	}
 	if (maxy == -1) return; // No image
-	points.push_back(wxPoint(lastx-1,maxy+1));
-	make_convex(points);
+	add_convex_point(points, lastx-1, maxy+1);
 	// Right side, bottom to top
 	for (int y = maxy ; y >= miny ; --y) {
 		for (int x = size.x - 1 ; x >= 0 ; --x) {
 			if (alpha[x + y * size.x] >= 20) {
 				// opaque pixel
 				if (y == maxy) {
-					points.push_back(wxPoint(x+1,y+1));
-					make_convex(points);
+					add_convex_point(points, x+1, y+1);
 				}
-				points.push_back(wxPoint(x+1,y));
-				make_convex(points);
+				add_convex_point(points, x+1, y);
 				lastx = x;
 				break;
 			}
 		}
 	}
-	points.push_back(wxPoint(lastx+1,miny-1));
-	make_convex(points);
+	add_convex_point(points, lastx+1, miny-1);
 }
 
 Image AlphaMask::colorImage(const Color& color) const {
@@ -142,7 +149,7 @@ void AlphaMask::loadRowSizes() const {
 	}
 }
 
-double AlphaMask::rowLeft (double y, RealSize resize) const {
+double AlphaMask::rowLeft (double y, const RealSize& resize) const {
 	loadRowSizes();
 	if (!lefts || y < 0 || y >= resize.height) {
 		// no mask, or outside it
@@ -151,7 +158,7 @@ double AlphaMask::rowLeft (double y, RealSize resize) const {
 	return lefts[(int)(y * resize.height / size.y)] * resize.width / size.x;
 }
 
-double AlphaMask::rowRight(double y, RealSize resize) const {
+double AlphaMask::rowRight(double y, const RealSize& resize) const {
 	loadRowSizes();
 	if (!rights || y < 0 || y >= resize.height) {
 		// no mask, or outside it
diff --git a/src/gui/image_slice_window.cpp b/src/gui/image_slice_window.cpp
index 94bdd1dd..8bd0559a 100644
--- a/src/gui/image_slice_window.cpp
+++ b/src/gui/image_slice_window.cpp
@@ -54,7 +54,7 @@ void ImageSlice::constrain(PreferedProperty prefer) {
 Image ImageSlice::getSlice() const {
 	if (selection.width == target_size.GetWidth() && selection.height == target_size.GetHeight() && selection.x == 0 && selection.y == 0) {
 		// exactly the right size
-		return source;
+		return source.GetSubImage(selection);
 	}
 	Image target(target_size.GetWidth(), target_size.GetHeight(), false);
 	if (sharpen && sharpen_amount > 0 && sharpen_amount <= 100) {
@@ -75,7 +75,7 @@ DEFINE_EVENT_TYPE(EVENT_SLICE_CHANGED);
 
 // ----------------------------------------------------------------------------- : ImageSliceWindow
 
-ImageSliceWindow::ImageSliceWindow(Window* parent, const Image& source, const wxSize& target_size, const AlphaMaskP& mask)
+ImageSliceWindow::ImageSliceWindow(Window* parent, const Image& source, const wxSize& target_size, const AlphaMask& mask)
 	: wxDialog(parent,wxID_ANY,_TITLE_("slice image"), wxDefaultPosition, wxDefaultSize, wxDEFAULT_DIALOG_STYLE | wxRESIZE_BORDER | wxFULL_REPAINT_ON_RESIZE)
 	, slice(source, target_size)
 {
@@ -277,6 +277,7 @@ void ImageSliceWindow::updateControls() {
 		size->SetSelection(2); // force to fit
 	} else if (slice.selection.width  <= slice.source.GetWidth()  &&
 	           slice.selection.height <= slice.source.GetHeight() &&
+	           fabs(slice.zoomX() - slice.zoomY()) < 0.01 &&
 		        (  (slice.selection.x == 0 && slice.selection.width  == slice.source.GetWidth())
 		         ||(slice.selection.y == 0 && slice.selection.height == slice.source.GetHeight()))) {
 		size->SetSelection(1); // size to fit
@@ -334,7 +335,7 @@ END_EVENT_TABLE  ()
 
 // ----------------------------------------------------------------------------- : ImageSlicePreview
 
-ImageSlicePreview::ImageSlicePreview(Window* parent, int id, ImageSlice& slice, const AlphaMaskP& mask)
+ImageSlicePreview::ImageSlicePreview(Window* parent, int id, ImageSlice& slice, const AlphaMask& mask)
 	: wxControl(parent, id)
 	, slice(slice)
 	, mask(mask)
@@ -359,9 +360,8 @@ void ImageSlicePreview::onPaint(wxPaintEvent&) {
 void ImageSlicePreview::draw(DC& dc) {
 	if (!bitmap.Ok()) {
 		Image image = slice.getSlice();
-		if (mask && mask->hasSize(slice.target_size)) {
-			mask->setAlpha(image);
-		}
+		assert(image.GetWidth() == slice.target_size.GetWidth() && image.GetHeight() == slice.target_size.GetHeight());
+		mask.setAlpha(image);
 		if (image.HasAlpha()) {
 			// create bitmap
 			bitmap = Bitmap(image.GetWidth(), image.GetHeight());
diff --git a/src/gui/image_slice_window.hpp b/src/gui/image_slice_window.hpp
index dafd192d..a9509fc0 100644
--- a/src/gui/image_slice_window.hpp
+++ b/src/gui/image_slice_window.hpp
@@ -59,7 +59,7 @@ class ImageSlice {
 /// Dialog for selecting a slice of an image
 class ImageSliceWindow : public wxDialog {
   public:
-	ImageSliceWindow(Window* parent, const Image& source, const wxSize& target_size, const AlphaMaskP& target_mask);
+	ImageSliceWindow(Window* parent, const Image& source, const wxSize& target_size, const AlphaMask& target_mask);
 	
 	/// Return the sliced image
 	Image getImage() const;
@@ -115,7 +115,7 @@ class ImageSliceWindow : public wxDialog {
 /// A preview of the sliced image
 class ImageSlicePreview : public wxControl {
   public:
-	ImageSlicePreview(Window* parent, int id, ImageSlice& slice, const AlphaMaskP& mask);
+	ImageSlicePreview(Window* parent, int id, ImageSlice& slice, const AlphaMask& mask);
 	
 	/// Notify that the slice was updated
 	void update();
@@ -124,7 +124,7 @@ class ImageSlicePreview : public wxControl {
   private:
 	Bitmap bitmap;
 	ImageSlice& slice;
-	AlphaMaskP mask;
+	const AlphaMask& mask;
 	
 	bool mouse_down;
 	int mouseX, mouseY;		///< starting mouse position
diff --git a/src/gui/value/image.cpp b/src/gui/value/image.cpp
index 41f771fa..c0821fb2 100644
--- a/src/gui/value/image.cpp
+++ b/src/gui/value/image.cpp
@@ -29,17 +29,10 @@ bool ImageValueEditor::onLeftDClick(const RealPoint&, wxMouseEvent&) {
 
 void ImageValueEditor::sliceImage(const Image& image) {
 	if (!image.Ok()) return;
-	// mask?
-	AlphaMaskP mask;
-	if (!style().mask_filename().empty()) {
-		Image mask_image;
-		InputStreamP image_file = getStylePackage().openIn(style().mask_filename);
-		if (mask_image.LoadFile(*image_file)) {
-			Image resampled(style().width, style().height);
-			resample(mask_image, resampled);
-			mask = new_intrusive1<AlphaMask>(resampled);
-		}
-	}
+	// mask
+	GeneratedImage::Options options((int)style().width, (int)style().height, &viewer.getStylePackage(), &viewer.getLocalPackage());
+	AlphaMask mask;
+	style().mask.getNoCache(options,mask);
 	// slice
 	ImageSliceWindow s(wxGetTopLevelParent(&editor()), image, style().getSize(), mask);
 	// clicked ok?
diff --git a/src/render/value/choice.cpp b/src/render/value/choice.cpp
index 1664fc9f..6b74a37c 100644
--- a/src/render/value/choice.cpp
+++ b/src/render/value/choice.cpp
@@ -10,6 +10,8 @@
 #include <render/value/choice.hpp>
 #include <render/card/viewer.hpp>
 
+DECLARE_TYPEOF_COLLECTION(wxPoint);
+
 // ----------------------------------------------------------------------------- : ChoiceValueViewer
 
 IMPLEMENT_VALUE_VIEWER(Choice);
@@ -20,11 +22,48 @@ bool ChoiceValueViewer::prepare(RotatedDC& dc) {
 	return prepare_choice_viewer(dc, *this, style(), value().value());
 }
 void ChoiceValueViewer::draw(RotatedDC& dc) {
-	drawFieldBorder(dc);
+	int w = max(0,(int)dc.trX(style().width)), h = max(0,(int)dc.trY(style().height));
+	const AlphaMask& alpha_mask = getMask(w,h);
+	drawFieldBorder(dc, alpha_mask);
 	if (style().render_style & RENDER_HIDDEN) return;
 	draw_choice_viewer(dc, *this, style(), value().value());
 }
 
+void ChoiceValueViewer::drawFieldBorder(RotatedDC& dc, const AlphaMask& alpha_mask) {
+	if (!alpha_mask.isLoaded()) {
+		ValueViewer::drawFieldBorder(dc);
+	} else if (setFieldBorderPen(dc)) {
+		dc.SetBrush(*wxTRANSPARENT_BRUSH);
+		vector<wxPoint> points;
+		alpha_mask.convexHull(points);
+		if (points.size() < 3) return;
+		FOR_EACH(p, points) p = dc.trPixelNoZoom(RealPoint(p.x,p.y));
+		dc.getDC().DrawPolygon((int)points.size(), &points[0]);
+	}
+}
+
+bool ChoiceValueViewer::containsPoint(const RealPoint& p) const {
+	// check against mask
+	return getMask(0,0).isOpaque(p, style().getSize());
+}
+
+void ChoiceValueViewer::onStyleChange(int changes) {
+	if (changes & CHANGE_MASK) style().image.clearCache();
+	ValueViewer::onStyleChange(changes);
+}
+
+const AlphaMask& ChoiceValueViewer::getMask(int w, int h) const {
+	GeneratedImage::Options opts;
+	opts.package       = &viewer.getStylePackage();
+	opts.local_package = &viewer.getLocalPackage();
+	opts.angle         = 0;
+	opts.width         = w;
+	opts.height        = h;
+	return style().mask.get(opts);
+}
+
+// ----------------------------------------------------------------------------- : Generic draw/prepare
+
 bool prepare_choice_viewer(RotatedDC& dc, ValueViewer& viewer, ChoiceStyle& style, const String& value) {
 	if (style.render_style & RENDER_IMAGE) {
 		style.initImage();
@@ -38,7 +77,6 @@ bool prepare_choice_viewer(RotatedDC& dc, ValueViewer& viewer, ChoiceStyle& styl
 			// Generate image/bitmap (whichever is available)
 			// don't worry, we cache the image
 			ImageCombine combine = style.combine;
-			style.loadMask(viewer.getStylePackage());
 			Bitmap bitmap; Image image;
 			RealSize size;
 			img.generateCached(img_options, &style.mask, &combine, &bitmap, &image, &size);
@@ -70,7 +108,6 @@ void draw_choice_viewer(RotatedDC& dc, ValueViewer& viewer, ChoiceStyle& style,
 			get_options(dc, viewer, style, img_options);
 			// Generate image/bitmap
 			ImageCombine combine = style.combine;
-			style.loadMask(viewer.getStylePackage());
 			Bitmap bitmap; Image image;
 			RealSize size;
 			img.generateCached(img_options, &style.mask, &combine, &bitmap, &image, &size);
@@ -112,8 +149,3 @@ void get_options(Rotation& rot, ValueViewer& viewer, const ChoiceStyle& style, G
 		opts.preserve_aspect = (style.alignment & ALIGN_STRETCH) ? ASPECT_STRETCH : ASPECT_FIT;
 	}
 }
-
-void ChoiceValueViewer::onStyleChange(int changes) {
-	if (changes & CHANGE_MASK) style().image.clearCache();
-	ValueViewer::onStyleChange(changes);
-}
diff --git a/src/render/value/choice.hpp b/src/render/value/choice.hpp
index 6ddf34db..c7af7b04 100644
--- a/src/render/value/choice.hpp
+++ b/src/render/value/choice.hpp
@@ -23,10 +23,19 @@ class ChoiceValueViewer : public ValueViewer {
 	virtual bool prepare(RotatedDC& dc);
 	virtual void draw(RotatedDC& dc);
 	virtual void onStyleChange(int);
+	
+	virtual bool containsPoint(const RealPoint& p) const;
+	
+  private:
+	/// Draws a border around the field
+	void drawFieldBorder(RotatedDC& dc, const AlphaMask& alpha_mask);
+	/// Load the AlphaMask for this field
+	const AlphaMask& getMask(int w, int h) const;
 };
 
 bool prepare_choice_viewer(RotatedDC& dc, ValueViewer& viewer, ChoiceStyle& style, const String& value);
 void draw_choice_viewer(RotatedDC& dc, ValueViewer& viewer, ChoiceStyle& style, const String& value);
+const AlphaMask& get_mask(RotatedDC& dc, ValueViewer& viewer, ChoiceStyle& style, int w, int h);
 
 // ----------------------------------------------------------------------------- : EOF
 #endif
diff --git a/src/render/value/color.cpp b/src/render/value/color.cpp
index 531cff8e..2db0087a 100644
--- a/src/render/value/color.cpp
+++ b/src/render/value/color.cpp
@@ -11,6 +11,7 @@
 #include <render/card/viewer.hpp>
 
 DECLARE_TYPEOF_COLLECTION(ColorField::ChoiceP);
+DECLARE_TYPEOF_COLLECTION(wxPoint);
 
 // ----------------------------------------------------------------------------- : ColorValueViewer
 
@@ -43,9 +44,10 @@ void ColorValueViewer::draw(RotatedDC& dc) {
 		dc.DrawText(color_name, RealPoint(43, 3));
 	} else {
 		// is there a mask?
-		loadMask(dc);
-		if (alpha_mask) {
-			dc.DrawImage(alpha_mask->colorImage(value().value()), RealPoint(0,0), style().combine);
+		int w = max(0,(int)dc.trX(style().width)), h = max(0,(int)dc.trY(style().height));
+		const AlphaMask& alpha_mask = getMask(w,h);
+		if (alpha_mask.isLoaded()) {
+			dc.DrawImage(alpha_mask.colorImage(value().value()), RealPoint(0,0), style().combine);
 		} else {
 			// do we need clipping?
 			bool clip = style().left_width < style().width  && style().right_width  < style().width &&
@@ -64,43 +66,45 @@ void ColorValueViewer::draw(RotatedDC& dc) {
 			dc.DrawRoundedRectangle(style().getInternalRect(), style().radius);
 			if (clip) dc.getDC().DestroyClippingRegion();
 		}
+		drawFieldBorder(dc, alpha_mask);
+	}
+}
+
+void ColorValueViewer::drawFieldBorder(RotatedDC& dc, const AlphaMask& alpha_mask) {
+	if (!alpha_mask.isLoaded()) {
+		ValueViewer::drawFieldBorder(dc);
+	} else if (setFieldBorderPen(dc)) {
+		dc.SetBrush(*wxTRANSPARENT_BRUSH);
+		vector<wxPoint> points;
+		alpha_mask.convexHull(points);
+		if (points.size() < 3) return;
+		FOR_EACH(p, points) p = dc.trPixelNoZoom(RealPoint(p.x,p.y));
+		dc.getDC().DrawPolygon((int)points.size(), &points[0]);
 	}
 }
 
 bool ColorValueViewer::containsPoint(const RealPoint& p) const {
-	// distance to each side
-	double left = p.x, right  = style().width  - p.x - 1;
-	double top  = p.y, bottom = style().height - p.y - 1;
-	if (left < 0 || right < 0 || top < 0 || bottom < 0) return false;  // outside bounding box
 	// check against mask
-	if (!style().mask_filename().empty()) loadMask(getRotation());
-	if (alpha_mask) {
-		return !alpha_mask->isTransparent((int)left, (int)top);
+	const AlphaMask& alpha_mask = getMask(0,0);
+	if (alpha_mask.isLoaded()) {
+		// check against mask
+		return alpha_mask.isOpaque(p, style().getSize());
 	} else {
+		double left = p.x, right  = style().width  - p.x - 1;
+		double top  = p.y, bottom = style().height - p.y - 1;
+		if (left < 0 || right < 0 || top < 0 || bottom < 0) return false;  // outside bounding box
 		// check against border
-		if (left >= style().left_width && right  >= style().right_width &&  // outside horizontal border
-		    top  >= style().top_width  && bottom >= style().bottom_width) { // outside vertical border
-			return false;
-		}
-		return true;
+		return left < style().left_width || right  < style().right_width   // inside horizontal border
+			|| top  < style().top_width  || bottom < style().bottom_width; // inside vertical border
 	}
 }
 
-void ColorValueViewer::onStyleChange(int changes) {
-	if (changes & CHANGE_MASK) alpha_mask = AlphaMaskP();
-	ValueViewer::onStyleChange(changes);
-}
-
-void ColorValueViewer::loadMask(const Rotation& rot) const {
-	if (style().mask_filename().empty()) return; // no mask
-	int w = (int) rot.trX(rot.getWidth()), h = (int) rot.trY(rot.getHeight());
-	if (alpha_mask && alpha_mask->hasSize(wxSize(w,h))) return; // mask loaded and right size
-	// (re) load the mask
-	Image image;
-	InputStreamP image_file = getStylePackage().openIn(style().mask_filename);
-	if (image.LoadFile(*image_file)) {
-		Image resampled(w,h);
-		resample(image, resampled);
-		alpha_mask = new_intrusive1<AlphaMask>(resampled);
-	}
+const AlphaMask& ColorValueViewer::getMask(int w, int h) const {
+	GeneratedImage::Options opts;
+	opts.package       = &viewer.getStylePackage();
+	opts.local_package = &viewer.getLocalPackage();
+	opts.angle         = 0;
+	opts.width         = w;
+	opts.height        = h;
+	return style().mask.get(opts);
 }
diff --git a/src/render/value/color.hpp b/src/render/value/color.hpp
index a2d6cff7..fe669b78 100644
--- a/src/render/value/color.hpp
+++ b/src/render/value/color.hpp
@@ -25,11 +25,11 @@ class ColorValueViewer : public ValueViewer {
 	virtual void draw(RotatedDC& dc);
 	virtual bool containsPoint(const RealPoint& p) const;
 	
-	virtual void onStyleChange(int);
-	
   private:
-	mutable AlphaMaskP alpha_mask;
-	void loadMask(const Rotation& rot) const;
+	/// Draws a border around the field
+	void drawFieldBorder(RotatedDC& dc, const AlphaMask& alpha_mask);
+	/// Load the AlphaMask for this field
+	const AlphaMask& getMask(int w, int h) const;
 };
 
 // ----------------------------------------------------------------------------- : EOF
diff --git a/src/render/value/image.cpp b/src/render/value/image.cpp
index fc98aa8f..2bd8fa36 100644
--- a/src/render/value/image.cpp
+++ b/src/render/value/image.cpp
@@ -22,6 +22,7 @@ void ImageValueViewer::draw(RotatedDC& dc) {
 	// reset?
 	int w = max(0,(int)dc.trX(style().width)), h = max(0,(int)dc.trY(style().height));
 	int a = dc.trAngle(0); //% TODO : Add getAngle()?
+	const AlphaMask& alpha_mask = getMask(w,h);
 	if (bitmap.Ok() && (a != angle || size.width != w || size.height != h)) {
 		bitmap = Bitmap();
 	}
@@ -30,7 +31,6 @@ void ImageValueViewer::draw(RotatedDC& dc) {
 		angle = a;
 		is_default = false;
 		Image image;
-		loadMask(dc);
 		// load from file
 		if (!value().filename.empty()) {
 			try {
@@ -48,7 +48,7 @@ void ImageValueViewer::draw(RotatedDC& dc) {
 			is_default = true;
 			if (what & DRAW_EDITING) {
 				bitmap = imagePlaceholder(dc, w, h, image, what & DRAW_EDITING);
-				if (alpha_mask || a) {
+				if (alpha_mask.isLoaded() || a) {
 					image = bitmap.ConvertToImage(); // we need to convert back to an image
 				} else {
 					image = Image();
@@ -59,7 +59,7 @@ void ImageValueViewer::draw(RotatedDC& dc) {
 		if (!image.Ok() && !bitmap.Ok() && style().width > 40) {
 			// placeholder bitmap
 			bitmap = imagePlaceholder(dc, w, h, wxNullImage, what & DRAW_EDITING);
-			if (alpha_mask || a) {
+			if (alpha_mask.isLoaded() || a) {
 				// we need to convert back to an image
 				image = bitmap.ConvertToImage();
 			}
@@ -67,27 +67,27 @@ void ImageValueViewer::draw(RotatedDC& dc) {
 		// done
 		if (image.Ok()) {
 			// apply mask and rotate
-			if (alpha_mask) alpha_mask->setAlpha(image);
+			alpha_mask.setAlpha(image);
 			size = RealSize(image);
 			image = rotate_image(image, angle);
 			bitmap = Bitmap(image);
 		}
 	}
 	// border
-	drawFieldBorder(dc);
+	drawFieldBorder(dc, alpha_mask);
 	// draw image, if any
 	if (bitmap.Ok()) {
 		dc.DrawPreRotatedBitmap(bitmap, dc.getInternalRect());
 	}
 }
 
-void ImageValueViewer::drawFieldBorder(RotatedDC& dc) {
-	if (!alpha_mask) {
+void ImageValueViewer::drawFieldBorder(RotatedDC& dc, const AlphaMask& alpha_mask) {
+	if (!alpha_mask.isLoaded()) {
 		ValueViewer::drawFieldBorder(dc);
 	} else if (setFieldBorderPen(dc)) {
 		dc.SetBrush(*wxTRANSPARENT_BRUSH);
 		vector<wxPoint> points;
-		alpha_mask->convexHull(points);
+		alpha_mask.convexHull(points);
 		if (points.size() < 3) return;
 		FOR_EACH(p, points) p = dc.trPixelNoZoom(RealPoint(p.x,p.y));
 		dc.getDC().DrawPolygon((int)points.size(), &points[0]);
@@ -95,14 +95,8 @@ void ImageValueViewer::drawFieldBorder(RotatedDC& dc) {
 }
 
 bool ImageValueViewer::containsPoint(const RealPoint& p) const {
-	if (!ValueViewer::containsPoint(p)) return false;
 	// check against mask
-	if (!style().mask_filename().empty()) {
-		loadMask(getRotation());
-		return !alpha_mask || !alpha_mask->isTransparent((int)p.x, (int)p.y);
-	} else {
-		return true;
-	}
+	return getMask(0,0).isOpaque(p, style().getSize());
 }
 
 void ImageValueViewer::onValueChange() {
@@ -114,20 +108,17 @@ void ImageValueViewer::onStyleChange(int changes) {
 	    ((changes & CHANGE_DEFAULT) && is_default)) {
 		bitmap = Bitmap();
 	}
-	if (changes & CHANGE_MASK) alpha_mask = AlphaMaskP();
 	ValueViewer::onStyleChange(changes);
 }
 
-void ImageValueViewer::loadMask(const Rotation& rot) const {
-	if (style().mask_filename().empty()) return; // no mask
-	int w = (int) rot.trX(style().width), h = (int) rot.trY(style().height);
-	if (alpha_mask && alpha_mask->hasSize(wxSize(w,h))) return; // mask loaded and right size
-	// (re) load the mask
-	Image image;
-	InputStreamP image_file = getStylePackage().openIn(style().mask_filename);
-	if (image.LoadFile(*image_file)) {
-		alpha_mask = new_intrusive1<AlphaMask>(resample(image,w,h));
-	}
+const AlphaMask& ImageValueViewer::getMask(int w, int h) const {
+	GeneratedImage::Options opts;
+	opts.package       = &viewer.getStylePackage();
+	opts.local_package = &viewer.getLocalPackage();
+	opts.angle         = 0;
+	opts.width         = w;
+	opts.height        = h;
+	return style().mask.get(opts);
 }
 
 // is an image very light?
diff --git a/src/render/value/image.hpp b/src/render/value/image.hpp
index ef490a43..4fc93336 100644
--- a/src/render/value/image.hpp
+++ b/src/render/value/image.hpp
@@ -34,15 +34,15 @@ class ImageValueViewer : public ValueViewer {
 	RealSize size; ///< Size of cached bitmap
 	int    angle;  ///< Angle of cached bitmap
 	int    is_default; ///< Is the default placeholder image used?
-	mutable AlphaMaskP alpha_mask;
-	
-	void loadMask(const Rotation& rot) const;
 	
 	/// Generate a placeholder image
 	static Bitmap imagePlaceholder(const Rotation& rot, UInt w, UInt h, const Image& background, bool editing);
 	
 	/// Draws a border around the field
-	void drawFieldBorder(RotatedDC& dc);
+	void drawFieldBorder(RotatedDC& dc, const AlphaMask& alpha_mask);
+	
+	/// Load the AlphaMask for this field
+	const AlphaMask& getMask(int w, int h) const;
 };
 
 // ----------------------------------------------------------------------------- : EOF
diff --git a/src/render/value/multiple_choice.cpp b/src/render/value/multiple_choice.cpp
index 1afad23c..000ecbda 100644
--- a/src/render/value/multiple_choice.cpp
+++ b/src/render/value/multiple_choice.cpp
@@ -13,6 +13,7 @@
 #include <gui/util.hpp>
 
 DECLARE_TYPEOF_COLLECTION(String);
+DECLARE_TYPEOF_COLLECTION(wxPoint);
 
 // ----------------------------------------------------------------------------- : MultipleChoiceValueViewer
 
@@ -24,7 +25,9 @@ bool MultipleChoiceValueViewer::prepare(RotatedDC& dc) {
 }
 
 void MultipleChoiceValueViewer::draw(RotatedDC& dc) {
-	drawFieldBorder(dc);
+	int w = max(0,(int)dc.trX(style().width)), h = max(0,(int)dc.trY(style().height));
+	const AlphaMask& alpha_mask = getMask(w,h);
+	drawFieldBorder(dc, alpha_mask);
 	if (style().render_style & RENDER_HIDDEN) return;
 	RealPoint pos = align_in_rect(style().alignment, RealSize(0,0), style().getInternalRect());
 	// selected choices
@@ -83,7 +86,35 @@ void MultipleChoiceValueViewer::drawChoice(RotatedDC& dc, RealPoint& pos, const
 	pos = move_in_direction(style().direction, pos, size, style().spacing);
 }
 
+void MultipleChoiceValueViewer::drawFieldBorder(RotatedDC& dc, const AlphaMask& alpha_mask) {
+	if (!alpha_mask.isLoaded()) {
+		ValueViewer::drawFieldBorder(dc);
+	} else if (setFieldBorderPen(dc)) {
+		dc.SetBrush(*wxTRANSPARENT_BRUSH);
+		vector<wxPoint> points;
+		alpha_mask.convexHull(points);
+		if (points.size() < 3) return;
+		FOR_EACH(p, points) p = dc.trPixelNoZoom(RealPoint(p.x,p.y));
+		dc.getDC().DrawPolygon((int)points.size(), &points[0]);
+	}
+}
+
+bool MultipleChoiceValueViewer::containsPoint(const RealPoint& p) const {
+	// check against mask
+	return getMask(0,0).isOpaque(p, style().getSize());
+}
+
 void MultipleChoiceValueViewer::onStyleChange(int changes) {
 	if (changes & CHANGE_MASK) style().image.clearCache();
 	ValueViewer::onStyleChange(changes);
 }
+
+const AlphaMask& MultipleChoiceValueViewer::getMask(int w, int h) const {
+	GeneratedImage::Options opts;
+	opts.package       = &viewer.getStylePackage();
+	opts.local_package = &viewer.getLocalPackage();
+	opts.angle         = 0;
+	opts.width         = w;
+	opts.height        = h;
+	return style().mask.get(opts);
+}
diff --git a/src/render/value/multiple_choice.hpp b/src/render/value/multiple_choice.hpp
index 8efadf1c..d312547a 100644
--- a/src/render/value/multiple_choice.hpp
+++ b/src/render/value/multiple_choice.hpp
@@ -23,10 +23,15 @@ class MultipleChoiceValueViewer : public ValueViewer {
 	virtual bool prepare(RotatedDC& dc);
 	virtual void draw(RotatedDC& dc);
 	virtual void onStyleChange(int);
+	virtual bool containsPoint(const RealPoint& p) const;
   protected:
 	double item_height; ///< Height of a single item, or 0 if non uniform
   private:
 	void drawChoice(RotatedDC& dc, RealPoint& pos, const String& choice, bool active = true);
+	/// Draws a border around the field
+	void drawFieldBorder(RotatedDC& dc, const AlphaMask& alpha_mask);
+	/// Load the AlphaMask for this field
+	const AlphaMask& getMask(int w, int h) const;
 };
 
 // ----------------------------------------------------------------------------- : EOF
diff --git a/src/script/image.cpp b/src/script/image.cpp
index acba6423..e98fe037 100644
--- a/src/script/image.cpp
+++ b/src/script/image.cpp
@@ -94,7 +94,7 @@ template <> void GetDefaultMember::handle(const ScriptableImage& s) {
 // ----------------------------------------------------------------------------- : CachedScriptableImage
 
 void CachedScriptableImage::generateCached(const GeneratedImage::Options& options,
-	                                       Image* mask,
+	                                       CachedScriptableMask* mask,
 	                                       ImageCombine* combine, wxBitmap* bitmap, wxImage* image, RealSize* size) {
 	// ready?
 	if (!isReady()) {
@@ -137,13 +137,24 @@ void CachedScriptableImage::generateCached(const GeneratedImage::Options& option
 			}
 		}
 	}
+	// hack: temporarily set angle to 0, do actual rotation after applying mask
+	int a = options.angle;
+	const_cast<GeneratedImage::Options&>(options).angle = 0;
 	// generate
 	cached_i = generate(options);
-	cached_angle = options.angle;
+	const_cast<GeneratedImage::Options&>(options).angle = cached_angle = a;
 	*size = cached_size = RealSize(options.width, options.height);
-	if (mask && mask->Ok()) {
+	if (mask) {
 		// apply mask
-		set_alpha(cached_i, *mask);
+		GeneratedImage::Options mask_opts(options);
+		mask_opts.width  = cached_i.GetWidth();
+		mask_opts.height = cached_i.GetHeight();
+		mask_opts.angle  = 0;
+		mask->get(mask_opts).setAlpha(cached_i);
+	}
+	if (options.angle != 0) {
+		// hack(pt2) do the actual rotation now
+		cached_i = rotate_image(cached_i, options.angle);
 	}
 	if (*combine <= COMBINE_NORMAL) {
 		*bitmap = cached_b = Bitmap(cached_i);
@@ -176,3 +187,45 @@ template <> void Writer::handle(const CachedScriptableImage& s) {
 template <> void GetDefaultMember::handle(const CachedScriptableImage& s) {
 	handle((const ScriptableImage&)s);
 }
+
+
+// ----------------------------------------------------------------------------- : CachedScriptableMask
+
+
+bool CachedScriptableMask::update(Context& ctx) {
+	if (script.update(ctx)) {
+		mask.clear();
+		return true;
+	} else {
+		return false;
+	}
+}
+
+const AlphaMask& CachedScriptableMask::get(const GeneratedImage::Options& img_options) {
+	if (mask.isLoaded()) {
+		// already loaded?
+		if (img_options.width == 0 && img_options.height == 0) return mask;
+		if (mask.hasSize(wxSize(img_options.width,img_options.height))) return mask;
+	}
+	// load?
+	getNoCache(img_options,mask);
+	return mask;
+}
+void CachedScriptableMask::getNoCache(const GeneratedImage::Options& img_options, AlphaMask& other_mask) {
+	if (script.isBlank()) {
+		other_mask.clear();
+	} else {
+		Image image = script.generate(img_options);
+		other_mask.load(image);
+	}
+}
+
+template <> void Reader::handle(CachedScriptableMask& i) {
+	handle(i.script);
+}
+template <> void Writer::handle(const CachedScriptableMask& i) {
+	handle(i.script);
+}
+template <> void GetDefaultMember::handle(const CachedScriptableMask& i) {
+	handle(i.script);
+}
diff --git a/src/script/image.hpp b/src/script/image.hpp
index ab1761a0..eb6a33e0 100644
--- a/src/script/image.hpp
+++ b/src/script/image.hpp
@@ -15,6 +15,8 @@
 #include <script/scriptable.hpp>
 #include <gfx/generated_image.hpp>
 
+class CachedScriptableMask;
+
 // ----------------------------------------------------------------------------- : ScriptableImage
 
 /// An image that can also be scripted
@@ -49,9 +51,10 @@ class ScriptableImage {
 	
 	/// Can this be safely generated from another thread?
 	inline bool threadSafe() const { return !value || value->threadSafe(); }
-	
 	/// Is this image specific to the set (the local_package)?
 	inline bool local() const { return value && value->local(); }
+	/// Is this image blank?
+	inline bool isBlank() const { return !value || value->isBlank(); }
 	
 	/// Get access to the script, be careful
 	inline Script& getMutableScript() { return script.getMutableScript(); }
@@ -89,7 +92,7 @@ class CachedScriptableImage : public ScriptableImage {
 	 *  Optionally, an alpha mask is applied to the image.
 	 */
 	void generateCached(const GeneratedImage::Options& img_options,
-	                    Image* mask,
+	                    CachedScriptableMask* mask,
 	                    ImageCombine* combine, wxBitmap* bitmap, wxImage* image, RealSize* size);
 	
 	/// Update the script, returns true if the value has changed
@@ -105,5 +108,29 @@ class CachedScriptableImage : public ScriptableImage {
 	int    cached_angle;
 };
 
+// ----------------------------------------------------------------------------- : CachedScriptableMask
+
+/// A version of ScriptableImage that caches an AlphaMask
+class CachedScriptableMask {
+  public:
+	
+	/// Update the script, returns true if the value has changed
+	bool update(Context& ctx);
+	
+	/// Get the alpha mask; with the given options
+	/** if img_options.width == 0 and the mask is already loaded, just returns it. */
+	const AlphaMask& get(const GeneratedImage::Options& img_options);
+	
+	/// Get a mask that is not cached
+	void getNoCache(const GeneratedImage::Options& img_options, AlphaMask& mask);
+	
+  private:
+	ScriptableImage script;
+	AlphaMask       mask;
+	friend class Reader;
+	friend class Writer;
+	friend class GetDefaultMember;
+};
+
 // ----------------------------------------------------------------------------- : EOF
 #endif
diff --git a/src/script/value.cpp b/src/script/value.cpp
index 6971ae4e..b14b7d28 100644
--- a/src/script/value.cpp
+++ b/src/script/value.cpp
@@ -277,7 +277,11 @@ class ScriptString : public ScriptValue {
 		return c;
 	}
 	virtual GeneratedImageP toImage(const ScriptValueP&) const {
-		return new_intrusive1<PackagedImage>(value);
+		if (value.empty()) {
+			return new_intrusive<BlankImage>();
+		} else {
+			return new_intrusive1<PackagedImage>(value);
+		}
 	}
 	virtual int itemCount() const { return (int)value.size(); }
 	virtual ScriptValueP getMember(const String& name) const {