I want to draw a 1px wide border around my custom NSView in DrawRect with NSBezierPath:
BorderColor.Set();
var path = NSBezierPath.FromRect(theRect);
path.LineWidth = 1;
path.Stroke();
Now BorderColor is set to NSColor.Gray, which I can see while debugging has an RGBA color code: (127,127,127,255)
But the 1px wide border which appears on the screen gets this color: (194,194,194,255)
When I set the path.LineWidth to 3, than I can see the 3 lines, the middle with wrong color (194..), the 2 wings with color (135,135,135,255) - which is close enough to the wanted (127..) color to be ok.
When I use four piece of 1px wide rectangles for border instead, and Fill these 4 rects, I also get the (135..) color, which is ok again.
I can use this rectangle based solution, I'm only wondering:
Is there a way to achieve the correct color for a 1px wide border with NSBezierPath.Stroke?
Assuming you're setting the stroke color correctly (we don't see how BorderColor is set up) it might be the case that you're measuring the color value on screen, which - in particular for a thin line - might have been anti-aliased so you're not seeing the original color but the output of the anti-aliasing algorithm.
Set the width to something bigger like 10 and measure the color in the middle of the 'blob' to make sure you're not chasing anti-aliasing artefacts..