some APIs refactoring

Author: jingwood

src/D2DLibExport/D2DDevice.cs

@@ -169,14 +169,6 @@ public D2DBitmap CreateBitmapFromMemory(UINT width, UINT height, UINT stride, In
 			return d2dbmp == HANDLE.Zero ? null : new D2DBitmap(d2dbmp);
 		}
 
-		public D2DBitmap CreateBitmapFromGDIBitmap(System.Drawing.Bitmap bmp)
-		{
-			bool useAlphaChannel =
-				(bmp.PixelFormat & System.Drawing.Imaging.PixelFormat.Alpha) == System.Drawing.Imaging.PixelFormat.Alpha;
-
-			return this.CreateBitmapFromGDIBitmap(bmp, useAlphaChannel);
-		}
-
     public D2DLayer CreateLayer()
     {
       return new D2DLayer(D2D.CreateLayer(this.Handle));
@@ -185,6 +177,14 @@ public D2DLayer CreateLayer()
 		[DllImport("gdi32.dll")]
 		public static extern bool DeleteObject(IntPtr obj);
 
+		public D2DBitmap CreateBitmapFromGDIBitmap(System.Drawing.Bitmap bmp)
+		{
+			bool useAlphaChannel =
+				(bmp.PixelFormat & System.Drawing.Imaging.PixelFormat.Alpha) == System.Drawing.Imaging.PixelFormat.Alpha;
+
+			return this.CreateBitmapFromGDIBitmap(bmp, useAlphaChannel);
+		}
+
 		public D2DBitmap CreateBitmapFromGDIBitmap(System.Drawing.Bitmap bmp, bool useAlphaChannel)
 		{
 			HANDLE d2dbmp = HANDLE.Zero;

src/D2DLibExport/D2DLib.cs

@@ -95,19 +95,6 @@ public static extern void DrawBitmapRenderTarget([In] HANDLE context, HANDLE bit
 		[DllImport(DLL_NAME, CallingConvention = CallingConvention.Cdecl)]
 		public static extern void DestroyBitmapRenderTarget([In] HANDLE context);
 
-		public static D2DBitmap CreateBitmapFromGDIBitmap(D2DDevice device, System.Drawing.Bitmap bmp)
-		{
-			bool useAlphaChannel =
-				(bmp.PixelFormat & System.Drawing.Imaging.PixelFormat.Alpha) == System.Drawing.Imaging.PixelFormat.Alpha;
-
-			return device.CreateBitmapFromGDIBitmap(bmp, useAlphaChannel);
-		}
-
-		public static D2DBitmap CreateBitmapFromGDIBitmap(D2DDevice device, System.Drawing.Bitmap bmp, bool useAlphaChannel)
-		{
-			HANDLE d2dbmp = D2D.CreateBitmapFromHBitmap(device.Handle, bmp.GetHbitmap(), useAlphaChannel);
-			return d2dbmp == HANDLE.Zero ? null : new D2DBitmap(d2dbmp);
-		}
 		[DllImport(DLL_NAME, CallingConvention = CallingConvention.Cdecl)]
 		public static extern HANDLE ResizeContext([In] HANDLE context);