From ca8f5eae936715c2e9db949f1f8ccddb74c40e58 Mon Sep 17 00:00:00 2001
From: Artur Wieczorek <artwik@wp.pl>
Date: Sun, 3 Jan 2016 15:10:16 +0100
Subject: [PATCH] Optimize converting internal GDI+ bitmap to wxImage

Write retrieved pixel data directly to the internal buffers of destination wxImage.
---
 src/msw/graphics.cpp | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/msw/graphics.cpp b/src/msw/graphics.cpp
index a164867c36..cfb7ad1acc 100644
--- a/src/msw/graphics.cpp
+++ b/src/msw/graphics.cpp
@@ -1118,16 +1118,18 @@ wxImage wxGDIPlusBitmapData::ConvertToImage() const
     Rect rect(0, 0, w, h);
     m_bitmap->LockBits(&rect, ImageLockModeRead, PixelFormat32bppARGB, &bitmapData);
 
+    unsigned char *imgRGB = img.GetData();    // destination RGB buffer
+    unsigned char *imgAlpha = img.GetAlpha(); // destination alpha buffer
     const BYTE* pixels = static_cast<const BYTE*>(bitmapData.Scan0);
     for( UINT y = 0; y < h; y++ )
     {
         for( UINT x = 0; x < w; x++ )
         {
             ARGB c = reinterpret_cast<const ARGB*>(pixels)[x];
-            img.SetRGB(x, y, (c >> 16) & 0xFF,
-                             (c >> 8) & 0xFF,
-                             (c >> 0) & 0xFF);
-            img.SetAlpha(x, y, (c >> 24) & 0xFF);
+            *imgRGB++ = (c >> 16) & 0xFF;  // R
+            *imgRGB++ = (c >> 8) & 0xFF;   // G
+            *imgRGB++ = (c >> 0) & 0xFF;   // B
+            *imgAlpha++ = (c >> 24) & 0xFF;
         }
 
         pixels += bitmapData.Stride;