+ support for conversion between indexed and RGBA images inside TFPMemoryImage

* TFPCustomImage moved near other TFPCustomImage mathods
* ColTransparent added to palette every time it is created : after an action on UsePalette
  before it was just in constructor so not presente after false then true assigned to UsePalette.

fcl/image/fpimage.inc

@@ -201,15 +201,20 @@ begin
   result := assigned(FPalette);
 end;
 
-procedure TFPCustomImage.SetUsePalette (Value : boolean);
+procedure TFPCustomImage.SetUsePalette(Value:boolean);
 begin
-  if Value <> assigned(FPalette) then
-    if Value then
-      FPalette := TFPPalette.Create (0)
+  if Value <> assigned(FPalette)
+  then
+    if Value
+    then
+      begin
+        FPalette := TFPPalette.Create (0);
+        FPalette.Add (colTransparent);    
+      end
     else
       begin
-      FPalette.Free;
-      FPalette := nil;
+        FPalette.Free;
+        FPalette := nil;
       end;
 end;
 
@@ -240,14 +245,47 @@ begin
     FonProgress(Sender,Stage,PercentDone,RedrawNow,R,Msg,Continue);
 end;                         
                          
+Procedure TFPCustomImage.Assign(Source: TPersistent);
+
+Var
+  Src : TFPCustomImage;
+  X,Y : Integer;
+
+begin
+  If Source is TFPCustomImage then
+    begin
+    Src:=TFPCustomImage(Source);
+    // Copy extra info
+    FExtra.Assign(Src.Fextra);
+    // Copy palette if needed.
+    UsePalette:=Src.UsePalette;
+    If UsePalette then
+      begin
+      Palette.Count:=0;
+      Palette.Build(Src);
+      end;
+    // Copy image.  
+    SetSize(Src.Width,Src.height);
+    If UsePalette then
+      For x:=0 to Src.Width-1 do
+        For y:=0 to src.Height-1 do
+          pixels[X,Y]:=src.pixels[X,Y]
+    else  
+      For x:=0 to Src.Width-1 do
+        For y:=0 to src.Height-1 do
+          self[X,Y]:=src[X,Y];
+    end
+  else  
+    Inherited Assign(Source);
+end;
 
 { TFPMemoryImage }
 
 constructor TFPMemoryImage.Create (AWidth,AHeight:integer);
 begin
   inherited create (AWidth,AHeight);
-  UsePalette := True;
-  Palette.Add (colTransparent);
+{Default behavior is to use palette as suggested by Michael}
+  SetUsePalette(True);
 end;
 
 destructor TFPMemoryImage.Destroy;
@@ -258,11 +296,29 @@ begin
   inherited Destroy;
 end;
 
+function TFPMemoryImage.GetInternalColor(x,y:integer):TFPColor;
+  begin
+    if Assigned(FPalette)
+    then
+      Result:=inherited GetInternalColor(x,y)
+    else
+      Result:=PFPColorArray(FData)^[y*FWidth+x];
+  end;
+
 function TFPMemoryImage.GetInternalPixel (x,y:integer) : integer;
 begin
   result := FData^[y*FWidth+x];
 end;
 
+procedure TFPMemoryImage.SetInternalColor (x,y:integer; const Value:TFPColor);
+  begin
+    if Assigned(FPalette)
+    then
+      inherited SetInternalColor(x,y,Value)
+    else
+      PFPColorArray(FData)^[y*FWidth+x]:=Value;
+  end;
+
 procedure TFPMemoryImage.SetInternalPixel (x,y:integer; Value:integer);
 begin
   FData^[y*FWidth+x] := Value;
@@ -283,7 +339,12 @@ begin
   if (AWidth <> Width) or (AHeight <> Height) then
     begin
     old := Height * Width;
-    r := SizeOf(integer)*AWidth*AHeight;
+    r:=AWidth*AHeight;
+    if Assigned(FPalette)
+    then
+      r:=SizeOf(integer)*r
+    else
+      r:=SizeOf(TFPColor)*r;
     if r = 0 then
       NewData := nil
     else
@@ -308,39 +369,35 @@ begin
     end;
 end;
 
-
-Procedure TFPCustomImage.Assign(Source: TPersistent);
-
-Var
-  Src : TFPCustomImage;
-  X,Y : Integer;
-
+procedure TFPMemoryImage.SetUsePalette(Value:boolean);
+var
+  OldColors:PFPColorArray;
+  OldPixels:PIntegerArray;
+  r,c:Integer;
 begin
-  If Source is TFPCustomImage then
-    begin
-    Src:=TFPCustomImage(Source);
-    // Copy extra info
-    FExtra.Assign(Src.Fextra);
-    // Copy palette if needed.
-    UsePalette:=Src.UsePalette;
-    If UsePalette then
+  if Value<>assigned(FPalette)
+  then
+    if Value
+    then
       begin
-      Palette.Count:=0;
-      Palette.Build(Src);
+        FPalette:=TFPPalette.Create(0);
+        FPalette.Add(colTransparent);    
+        OldColors:=PFPColorArray(FData);
+        GetMem(FData,FWidth*FHeight*SizeOf(Integer));
+        for r:=0 to FHeight-1 do
+          for c:=0 to FWidth-1 do
+            Colors[c,r]:=OldColors^[r*FWidth+c];
+        FreeMem(OldColors);
+      end
+    else
+      begin
+        OldPixels:=PIntegerArray(FData);
+        GetMem(FData,FWidth*FHeight*SizeOf(TFPColor));
+        for r:=0 to FHeight-1 do
+          for c:=0 to FWidth-1 do
+            Colors[c,r]:=FPalette.Color[OldPixels^[r*FWidth+c]];
+        FreeMem(OldPixels);
+        FPalette.Free;
+        FPalette:=nil;
       end;
-    // Copy image.  
-    SetSize(Src.Width,Src.height);
-    If UsePalette then
-      For x:=0 to Src.Width-1 do
-        For y:=0 to src.Height-1 do
-          pixels[X,Y]:=src.pixels[X,Y]
-    else  
-      For x:=0 to Src.Width-1 do
-        For y:=0 to src.Height-1 do
-          self[X,Y]:=src[X,Y];
-    end
-  else  
-    Inherited Assign(Source);
 end;
-
-