Update to CEF 3.3626.1891.g52be333

- Added transparency support to TBufferPanel.
- Added TBufferPanel.Transparent property
- Added TBufferPanel.OnPaintParentBkg event
- Added the TRANSPARENT_BROWSER constant in SimpleOSRBrowser to enable transparency

demos/SimpleOSRBrowser/SimpleOSRBrowser.dpr

@@ -55,9 +55,7 @@ uses
 {$SetPEFlags IMAGE_FILE_LARGE_ADDRESS_AWARE}
 
 begin
-  GlobalCEFApp                            := TCefApplication.Create;
-  GlobalCEFApp.WindowlessRenderingEnabled := True;
-  GlobalCEFApp.EnableHighDPISupport       := True;
+  CreateGlobalCEFApp;
 
   if GlobalCEFApp.StartMainProcess then
     begin
@@ -69,6 +67,5 @@ begin
       Application.Run;
     end;
 
-  GlobalCEFApp.Free;
-  GlobalCEFApp := nil;
+  DestroyGlobalCEFApp;
 end.

demos/SimpleOSRBrowser/uSimpleOSRBrowser.dfm

@@ -37,7 +37,7 @@ object Form1: TForm1
     object ComboBox1: TComboBox
       Left = 5
       Top = 5
-      Width = 909
+      Width = 907
       Height = 21
       Align = alClient
       ItemIndex = 0
@@ -51,12 +51,14 @@ object Form1: TForm1
           'https://www.w3schools.com/tags/tryit.asp?filename=tryhtml5_selec' +
           't_form'
         'https://www.briskbard.com'
-        'https://frames-per-second.appspot.com/')
+        'https://frames-per-second.appspot.com/'
+        'file:///transparency.html')
+      ExplicitWidth = 909
     end
     object Panel2: TPanel
-      Left = 914
+      Left = 912
       Top = 5
-      Width = 69
+      Width = 71
       Height = 20
       Margins.Left = 2
       Margins.Top = 2
@@ -80,7 +82,7 @@ object Form1: TForm1
         OnEnter = GoBtnEnter
       end
       object SnapshotBtn: TButton
-        Left = 38
+        Left = 40
         Top = 0
         Width = 31
         Height = 20
@@ -99,6 +101,7 @@ object Form1: TForm1
         TabOrder = 1
         OnClick = SnapshotBtnClick
         OnEnter = SnapshotBtnEnter
+        ExplicitLeft = 38
       end
     end
   end
@@ -110,8 +113,11 @@ object Form1: TForm1
     OnIMECancelComposition = Panel1IMECancelComposition
     OnIMECommitText = Panel1IMECommitText
     OnIMESetComposition = Panel1IMESetComposition
+    OnPaintParentBkg = Panel1PaintParentBkg
     Align = alClient
-    Caption = 'Panel1'
+    Ctl3D = False
+    ParentCtl3D = False
+    BevelOuter = bvNone
     TabOrder = 1
     TabStop = True
     OnClick = Panel1Click
@@ -122,6 +128,7 @@ object Form1: TForm1
     OnMouseUp = Panel1MouseUp
     OnResize = Panel1Resize
     OnMouseLeave = Panel1MouseLeave
+    ShowCaption = False
   end
   object chrmosr: TChromium
     OnTooltip = chrmosrTooltip

demos/SimpleOSRBrowser/uSimpleOSRBrowser.pas

@@ -52,6 +52,11 @@ uses
   {$ENDIF}
   uCEFChromium, uCEFTypes, uCEFInterfaces, uCEFConstants, uBufferPanel;
 
+const
+  // Set this constant to True and load "file://transparency.html" to test a
+  // transparent browser.
+  TRANSPARENT_BROWSER = False;
+
 type
   TForm1 = class(TForm)
     NavControlPnl: TPanel;
@@ -107,6 +112,7 @@ type
     procedure Timer1Timer(Sender: TObject);
     procedure SnapshotBtnEnter(Sender: TObject);
     procedure ComboBox1Enter(Sender: TObject);
+    procedure Panel1PaintParentBkg(Sender: TObject);
 
   protected
     FPopUpBitmap     : TBitmap;
@@ -149,6 +155,8 @@ type
 var
   Form1: TForm1;
 
+procedure CreateGlobalCEFApp;
+
 implementation
 
 {$R *.dfm}
@@ -168,6 +176,20 @@ uses
 // 3- chrmosr.OnBeforeClose is triggered because the internal browser was destroyed.
 //    Now we set FCanClose to True and send WM_CLOSE to the form.
 
+procedure CreateGlobalCEFApp;
+begin
+  GlobalCEFApp                            := TCefApplication.Create;
+  GlobalCEFApp.WindowlessRenderingEnabled := True;
+  GlobalCEFApp.EnableHighDPISupport       := True;
+
+  // If you need transparency leave the GlobalCEFApp.BackgroundColor property
+  // with the default value or set the alpha channel to 0
+  if TRANSPARENT_BROWSER then
+    GlobalCEFApp.BackgroundColor := CefColorSetARGB($00, $FF, $FF, $FF)
+   else
+    GlobalCEFApp.BackgroundColor := CefColorSetARGB($FF, $FF, $FF, $FF);
+end;
+
 procedure TForm1.AppEventsMessage(var Msg: tagMSG; var Handled: Boolean);
 var
   TempKeyEvent   : TCefKeyEvent;
@@ -663,6 +685,8 @@ begin
   FResizeCS       := TCriticalSection.Create;
   FIMECS          := TCriticalSection.Create;
 
+  Panel1.Transparent := TRANSPARENT_BROWSER;
+
   InitializeLastClick;
 end;
 
@@ -696,8 +720,12 @@ begin
     end
    else
     begin
-      // opaque white background color
-      chrmosr.Options.BackgroundColor := CefColorSetARGB($FF, $FF, $FF, $FF);
+      // If you need transparency leave the chrmosr.Options.BackgroundColor property
+      // with the default value or set the alpha channel to 0
+      if TRANSPARENT_BROWSER then
+        chrmosr.Options.BackgroundColor := CefColorSetARGB($00, $FF, $FF, $FF)
+       else
+        chrmosr.Options.BackgroundColor := CefColorSetARGB($FF, $FF, $FF, $FF);
 
       // The IME handler needs to be created when Panel1 has a valid handle
       // and before the browser creation.
@@ -797,6 +825,21 @@ begin
     end;
 end;
 
+procedure TForm1.Panel1PaintParentBkg(Sender: TObject);
+begin
+  // This event should only be used if you enabled transparency in the browser
+  if TRANSPARENT_BROWSER then
+    begin
+      // This event should copy the background image into Panel1.Canvas
+      // The TBufferPanel uses "AlphaBlend" to draw the browser contents over
+      // this background image.
+      // For simplicity, we just paint it green.
+      Panel1.Canvas.Brush.Color := clGreen;
+      Panel1.Canvas.Brush.Style := bsSolid;
+      Panel1.Canvas.FillRect(Rect(0, 0, Panel1.Width, Panel1.Height));
+    end;
+end;
+
 procedure TForm1.Panel1Resize(Sender: TObject);
 begin
   DoResize;