Fixed zoom crash;

Fixed crash when mising symbol font

src/gfx/generated_image.cpp

@@ -85,9 +85,11 @@ Image conform_image(const Image& img, const GeneratedImage::Options& options) {
 // ----------------------------------------------------------------------------- : BlankImage
 
 Image BlankImage::generate(const Options& opt) const {
-	Image img(opt.width, opt.height);
+	int w = max(1, opt.width >= 0  ? opt.width  : opt.height);
+	int h = max(1, opt.height >= 0 ? opt.height : opt.width);
+	Image img(w, h);
 	img.InitAlpha();
-	memset(img.GetAlpha(), 0, opt.width * opt.height);
+	memset(img.GetAlpha(), 0, w * h);
 	return img;
 }
 bool BlankImage::operator == (const GeneratedImage& that) const {

src/gfx/mask_image.cpp

@@ -44,7 +44,7 @@ void AlphaMask::setAlpha(Bitmap& bmp) const {
 }
 
 bool AlphaMask::isTransparent(int x, int y) const {
-	assert(x >= 0 && y >= 0 && x < size.GetWidth() && y < size.GetHeight());
+	if (x < 0 || y > 0 || x >= size.x || y >= size.y) return false;
 	return alpha[x + y * size.GetWidth()] < 20;
 }
 

src/render/value/image.cpp

@@ -110,7 +110,8 @@ bool ImageValueViewer::containsPoint(const RealPoint& p) const {
 	// check against mask
 	if (!style().mask_filename().empty()) {
 		loadMask(viewer.getRotation());
-		return !alpha_mask || !alpha_mask->isTransparent((int)x, (int)y);
+		Rotation rot = viewer.getRotation();
+		return !alpha_mask || !alpha_mask->isTransparent((int)rot.trX(x), (int)rot.trY(y));
 	} else {
 		return true;
 	}