From fda9deecd3200a13b571f918580ded13ce679ac8 Mon Sep 17 00:00:00 2001
From: ondrej <ondrej@lazarus-ide.org>
Date: Sun, 13 May 2018 20:57:16 +0000
Subject: [PATCH] Cocoa: TBitBtn retina support. Issue #33713

git-svn-id: trunk@57928 -
---
 lcl/interfaces/cocoa/cocoa_extra.pas   |  9 +++++++++
 lcl/interfaces/cocoa/cocoawsbuttons.pp | 12 ++++++++++--
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/lcl/interfaces/cocoa/cocoa_extra.pas b/lcl/interfaces/cocoa/cocoa_extra.pas
index 764c21e17a..535ed332da 100644
--- a/lcl/interfaces/cocoa/cocoa_extra.pas
+++ b/lcl/interfaces/cocoa/cocoa_extra.pas
@@ -26,6 +26,14 @@ uses
   // Libs
   MacOSAll, CocoaAll;
 
+type
+  NSImageScaling = NSUInteger;
+const // NSImageScaling values
+  NSImageScaleProportionallyDown = 0;
+  NSImageScaleAxesIndependently = 1;
+  NSImageScaleNone = 2;
+  NSImageScaleProportionallyUpOrDown = 3;
+
 type
   NSMenuFix = objccategory external (NSMenu)
     function itemAtIndex(index: NSInteger): NSMenuItem; message 'itemAtIndex:';
@@ -38,6 +46,7 @@ type
 
   NSButtonSoundExtensionsCategory = objccategory external (NSButton)
     function intrinsicContentSize(): NSSize; message 'intrinsicContentSize';
+    procedure setImageScaling(aScaling: NSImageScaling); message 'setImageScaling:';
   end;
 
   // The following dummy categories fix bugs in the Cocoa bindings available in FPC
diff --git a/lcl/interfaces/cocoa/cocoawsbuttons.pp b/lcl/interfaces/cocoa/cocoawsbuttons.pp
index 6539fc0a57..d51d74c75f 100644
--- a/lcl/interfaces/cocoa/cocoawsbuttons.pp
+++ b/lcl/interfaces/cocoa/cocoawsbuttons.pp
@@ -125,6 +125,7 @@ var
   AIndex: Integer;
   AEffect: TGraphicsDrawEffect;
   AImgRes: TScaledImageListResolution;
+  ImgSize: NSSize;
 begin
   //WriteLn('[TCocoaWSBitBtn.SetGlyph]');
   Img := nil;
@@ -132,13 +133,20 @@ begin
   begin
     AGlyph := TBitmap.Create;
     AValue.GetImageIndexAndEffect(bsUp, ABitBtn.Font.PixelsPerInch,
-      1{To-Do: ABitBtn.GetCanvasScaleFactor}, AImgRes, AIndex, AEffect);
+      ABitBtn.GetCanvasScaleFactor, AImgRes, AIndex, AEffect);
     AImgRes.GetBitmap(AIndex, AGlyph, AEffect);
     Img := TCocoaBitmap(AGlyph.Handle).image;
+    if AImgRes.Resolution.ImageList.Scaled then // resize only if the image list is scaled
+    begin
+      ImgSize := Img.size;
+      ImgSize.height := ImgSize.height / ABitBtn.GetCanvasScaleFactor;
+      ImgSize.width := ImgSize.width / ABitBtn.GetCanvasScaleFactor;
+      Img.setSize(ImgSize);
+    end;
     lButtonHandle := TCocoaButton(ABitBtn.Handle);
     lButtonHandle.setImage(Img);
     lButtonHandle.setImagePosition(LCLGlyphPosToCocoa(ABitBtn.Layout));
-    //To-Do: tell Cocoa lButtonHandle should not scale the image (and enable ABitBtn.GetCanvasScaleFactor above)
+    lButtonHandle.setImageScaling(NSImageScaleNone); // do not scale - retina scaling is done above with Img.setSize
     if Assigned(lButtonHandle.Glyph) then
       FreeAndNil(lButtonHandle.Glyph);
     lButtonHandle.Glyph := AGlyph;