Merge pull request #1817 from flibitijibibo/texture2d-gl-getdata

Texture2D: Fix OpenGL GetData with null Rect

MonoGame.Framework/Graphics/Texture2D.cs

@@ -667,28 +667,27 @@ public int Height
                 }
 
 #else
-			var temp = new T[this.width*this.height];
 
 			GL.BindTexture(TextureTarget.Texture2D, this.glTexture);
 
 			if (glFormat == (GLPixelFormat)All.CompressedTextureFormats) {
 				throw new NotImplementedException();
 			} else {
-				GL.GetTexImage(TextureTarget.Texture2D, level, this.glFormat, this.glType, temp);
-			}
-
-			if (rect.HasValue) {
-				int z = 0, w = 0;
-
-				for(int y= rect.Value.Y; y < rect.Value.Y+ rect.Value.Height; y++) {
-					for(int x=rect.Value.X; x < rect.Value.X + rect.Value.Width; x++) {
-						data[z*rect.Value.Width+w] = temp[(y*width)+x];
-						w++;
+				if (rect.HasValue) {
+					var temp = new T[this.width*this.height];
+					GL.GetTexImage(TextureTarget.Texture2D, level, this.glFormat, this.glType, temp);
+					int z = 0, w = 0;
+
+					for(int y= rect.Value.Y; y < rect.Value.Y+ rect.Value.Height; y++) {
+						for(int x=rect.Value.X; x < rect.Value.X + rect.Value.Width; x++) {
+							data[z*rect.Value.Width+w] = temp[(y*width)+x];
+							w++;
+						}
+						z++;
 					}
-					z++;
+				} else {
+					GL.GetTexImage(TextureTarget.Texture2D, level, this.glFormat, this.glType, data);
 				}
-			} else {
-				data = temp;
 			}
 
 #endif