From 48086503a6ce0e8d8ea3647317734ecb54c60796 Mon Sep 17 00:00:00 2001
From: duncanspumpkin <duncans_pumpkin@hotmail.co.uk>
Date: Wed, 21 Sep 2016 19:06:45 +0100
Subject: [PATCH] Fix zooming size for opengl sprites

---
 .../engines/opengl/OpenGLDrawingEngine.cpp      | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/src/drawing/engines/opengl/OpenGLDrawingEngine.cpp b/src/drawing/engines/opengl/OpenGLDrawingEngine.cpp
index a20ad0b956..2f21e0ef5b 100644
--- a/src/drawing/engines/opengl/OpenGLDrawingEngine.cpp
+++ b/src/drawing/engines/opengl/OpenGLDrawingEngine.cpp
@@ -680,9 +680,26 @@ void OpenGLDrawingContext::DrawSprite(uint32 image, sint32 x, sint32 y, uint32 t
 
     sint32 left = x + drawOffsetX;
     sint32 top = y + drawOffsetY;
+
+    int zoom_mask = 0xFFFFFFFF << _dpi->zoom_level;
+    if (_dpi->zoom_level && g1Element->flags & G1_FLAG_RLE_COMPRESSION){
+        top -= ~zoom_mask;
+    }
+
+    if (!(g1Element->flags & G1_FLAG_RLE_COMPRESSION)) {
+        top &= zoom_mask;
+        left += ~zoom_mask;
+    }
+
+    left &= zoom_mask;
+
     sint32 right = left + drawWidth;
     sint32 bottom = top + drawHeight;
 
+    if (_dpi->zoom_level && g1Element->flags & G1_FLAG_RLE_COMPRESSION) {
+        bottom += top & ~zoom_mask;
+    }
+
     if (left > right)
     {
         std::swap(left, right);