Fix pixel size calculation

src/olcPixelGameEngine.cpp

@@ -1170,7 +1170,7 @@ namespace olc
 	uint32_t PixelGameEngine::olc_GetMaximumPixelSize(uint32_t width, uint32_t height) 
 	{
 #ifdef _WIN32
-		return 1; // TODO 
+		return 1; // TODO
 #else
 		Display* d = XOpenDisplay(NULL);
 		int defaultScreen = DefaultScreen(d);
@@ -1187,9 +1187,9 @@ namespace olc
 			}
 		}
 
-		uint32_t minScreenSize = std::min(width, height);
+		uint32_t maxScreenSize = std::max(width, height);
 
-		return minResolution / minScreenSize;		
+		return minResolution / maxScreenSize;		
 #endif
 	}