cocoa: adding rotation of the cursor to make diagonal resizing cursors

git-svn-id: trunk@61423 -

lcl/interfaces/cocoa/cocoagdiobjects.pas

@@ -301,6 +301,7 @@ type
   public
     constructor CreateStandard(const ACursor: NSCursor);
     constructor CreateFromBitmap(const ABitmap: TCocoaBitmap; const hotSpot: NSPoint);
+    constructor CreateFromCustomCursor(const ACursor: NSCursor);
     destructor Destroy; override;
     function Install: TCocoaCursor;
     procedure SetCursor;
@@ -1185,6 +1186,12 @@ begin
   FStandard := False;
 end;
 
+constructor TCocoaCursor.CreateFromCustomCursor(const ACursor: NSCursor);
+begin
+  FCursor := ACursor;
+  FStandard := False;
+end;
+
 destructor TCocoaCursor.Destroy;
 begin
   FreeAndNil(FBitmap);

lcl/interfaces/cocoa/cocoalclintf.inc

@@ -36,16 +36,16 @@ begin
     crIBeam       : Result := HCursor(TCocoaCursor.CreateStandard(NSCursor.IBeamCursor));
     crSizeNS,
     crVSplit      : Result := HCursor(TCocoaCursor.CreateStandard(NSCursor.resizeUpDownCursor));
-    crSizeNESW,
+    crSizeNESW    : Result := HCursor(TCocoaCursor.CreateFromCustomCursor( AllocCursorFromCursorByDegrees(NSCursor.resizeLeftRightCursor, -45) ));
-    crSizeNWSE,
+    crSizeNWSE    : Result := HCursor(TCocoaCursor.CreateFromCustomCursor( AllocCursorFromCursorByDegrees(NSCursor.resizeLeftRightCursor,  45) ));
     crSizeWE,
     crHSplit      : Result := HCursor(TCocoaCursor.CreateStandard(NSCursor.resizeLeftRightCursor));
     crSizeN       : Result := HCursor(TCocoaCursor.CreateStandard(NSCursor.resizeUpCursor));
-    crSizeNW,
+    crSizeNW      : Result := HCursor(TCocoaCursor.CreateFromCustomCursor( AllocCursorFromCursorByDegrees(NSCursor.resizeLeftCursor, -45) ));
-    crSizeSW,
+    crSizeSW      : Result := HCursor(TCocoaCursor.CreateFromCustomCursor( AllocCursorFromCursorByDegrees(NSCursor.resizeLeftCursor, 45) ));
     crSizeW       : Result := HCursor(TCocoaCursor.CreateStandard(NSCursor.resizeLeftCursor));
-    crSizeNE,
+    crSizeNE      : Result := HCursor(TCocoaCursor.CreateFromCustomCursor( AllocCursorFromCursorByDegrees(NSCursor.resizeRightCursor,  45) ));
-    crSizeSE,
+    crSizeSE      : Result := HCursor(TCocoaCursor.CreateFromCustomCursor( AllocCursorFromCursorByDegrees(NSCursor.resizeRightCursor, -45) ));
     crSizeE       : Result := HCursor(TCocoaCursor.CreateStandard(NSCursor.resizeRightCursor));
     crSizeS       : Result := HCursor(TCocoaCursor.CreateStandard(NSCursor.resizeDownCursor));
     crNo,

lcl/interfaces/cocoa/cocoautils.pas

@@ -117,6 +117,9 @@ const
 
 function NSEventRawKeyChar(ev: NSEvent): System.WideChar;
 
+function AllocImageRotatedByDegrees(src: NSImage; degrees: double): NSImage;
+function AllocCursorFromCursorByDegrees(src: NSCursor; degrees: double): NSCursor;
+
 implementation
 
 procedure ApplicationWillShowModal;
@@ -938,5 +941,64 @@ begin
     Result := System.WideChar(m.characterAtIndex(0));
 end;
 
+function AllocImageRotatedByDegrees(src: NSImage; degrees: double): NSImage;
+var
+  imageBounds : NSRect;
+  pathBounds  : NSBezierPath;
+  transform   : NSAffineTransform;
+  rotatedBounds : NSRect;
+  rotatedImage   : NSImage;
+begin
+  if not Assigned(src) then
+  begin
+    Result := nil;
+    Exit;
+  end;
+
+  // src: https://stackoverflow.com/questions/31699235/rotate-nsimage-in-swift-cocoa-mac-osx
+
+  imageBounds.size := src.size;
+  pathBounds := NSBezierPath.bezierPathWithRect(imageBounds);
+  transform := NSAffineTransform.alloc.init;
+  transform.rotatebyDegrees(degrees);
+  pathBounds.transformUsingAffineTransform(transform);
+  rotatedBounds := NSMakeRect(NSZeroPoint.x, NSZeroPoint.y, src.size.width, src.size.height );
+  rotatedImage := NSImage(NSImage.alloc).initWithSize(rotatedBounds.size);
+
+  //Center the image within the rotated bounds
+  imageBounds.origin.x := NSMidX(rotatedBounds) - (NSWidth(imageBounds) / 2);
+  imageBounds.origin.y := NSMidY(rotatedBounds) - (NSHeight(imageBounds) / 2);
+  transform.release;
+
+  // Start a new transform
+  transform := NSAffineTransform.alloc.init;
+  // Move coordinate system to the center (since we want to rotate around the center)
+  transform.translateXBy_yBy(rotatedBounds.size.width / 2, rotatedBounds.size.width / 2);
+  transform.rotateByDegrees(degrees);
+  // Move the coordinate system bak to normal
+  transform.translateXBy_yBy(-rotatedBounds.size.width / 2, -rotatedBounds.size.height / 2);
+  // Draw the original image, rotated, into the new image
+  rotatedImage.lockFocus;
+  transform.concat();
+  src.drawInRect_fromRect_operation_fraction(imageBounds, NSZeroRect, NSCompositeCopy, 1.0);
+  rotatedImage.unlockFocus();
+  Result := rotatedImage;
+
+  transform.release;
+end;
+
+function AllocCursorFromCursorByDegrees(src: NSCursor; degrees: double): NSCursor;
+var
+  img : NSImage;
+begin
+  img := AllocImageRotatedByDegrees(src.image, degrees);
+  //todo: a better hotspot detection
+  Result := NSCursor.alloc.initWithImage_hotSpot(
+    img,
+    NSMakePoint(img.size.height / 2, img.size.width / 2)
+  );
+  img.release;
+end;
+
 end.