Fixed an issue displaying two screens of different size in the arrang…

…ement preference pane.

ArrangementPreviewView.m

@@ -29,26 +29,29 @@ - (void)drawRect:(NSRect)dirtyRect {
 
     NSArray *screens = [NSScreen screens];
     CGFloat xMax = 0, yMax = 0;
+    CGFloat xMin = 0, yMin = 0;
     for (NSScreen *screen in screens) {
         NSRect frame = [screen frame];
         CGFloat x = frame.origin.x + frame.size.width;
         CGFloat y = frame.origin.y + frame.size.height;
         xMax = MAX(xMax, x);
         yMax = MAX(yMax, y);
+        xMin = MIN(xMin, frame.origin.x);
+        yMin = MIN(yMin, frame.origin.y);
     }
 
-    double xScale = [self frame].size.width / xMax;
-    double yScale = [self frame].size.height / yMax;
+    double xScale = [self frame].size.width / (xMax - xMin);
+    double yScale = [self frame].size.height / (yMax - yMin);
     double scale = MIN(xScale, yScale);
-    double yCorrection = MAX(0, ([self frame].size.height - yMax * scale) / 2);
-    double xCorrection = MAX(0, ([self frame].size.width - xMax * scale) / 2);
+    double yCorrection = MAX(0, ([self frame].size.height - (yMax - yMin) * scale) / 2);
+    double xCorrection = MAX(0, ([self frame].size.width - (xMax - xMin) * scale) / 2);
 
     NSMutableArray *screenFrames = [NSMutableArray array];
     for (NSScreen *screen in screens) {
         NSRect frame = [screen frame];
 
-        NSRect rect = NSMakeRect(frame.origin.x * scale + xCorrection,
-                                 frame.origin.y * scale + yCorrection,
+        NSRect rect = NSMakeRect((frame.origin.x - xMin) * scale + xCorrection,
+                                 (yMax - frame.size.height - frame.origin.y) * scale + yCorrection,
                                  frame.size.width * scale,
                                  frame.size.height * scale);
         [[NSColor blackColor] set];