Draw an Inset NSShadow and Inset Stroke

Question

I have an NSBezierPath and I want to draw in inset shadow (similar to Photoshop) inside the path.

Is there anyway to do this? Also, I know you can -stroke paths, but can you stroke inside a path (similar to Stroke Inside in Photoshop)?

Update 3

static NSImage * graydient = nil;

if (!graydient) {
    graydient = [[NSImage alloc] initWithSize: NSMakeSize(22, 22)];
    [graydient lockFocus];

    NSGradient * gradient = [[NSGradient alloc] initWithColorsAndLocations: clr(@"#262729"), 0.0f, clr(@"#37383a"), 0.43f, clr(@"#37383a"), 1.0f, nil];
    [gradient drawInRect: NSMakeRect(0, 4.179, 22, 13.578) angle: 90.0f];
    [gradient release];

    [graydient unlockFocus];
}

NSColor * gcolor = [NSColor colorWithPatternImage: graydient];

[gcolor set];

NSShadow * shadow = [NSShadow new];
[shadow setShadowColor: [NSColor colorWithDeviceWhite: 1.0f alpha: 1.0f]];
[shadow setShadowBlurRadius: 0.0f];
[shadow setShadowOffset: NSMakeSize(0, 1)];
[shadow set];

[path fill];

[NSGraphicsContext saveGraphicsState];

[[path pathFromIntersectionWithPath: [NSBezierPath bezierPathWithRect: NSInsetRect([path bounds], 0.6, 0)]] setClip];

[gcolor set];

[shadow setShadowOffset: NSMakeSize(0, 1)];
[shadow setShadowColor: [NSColor blackColor]];
[shadow set];

[outer stroke];

[NSGraphicsContext restoreGraphicsState];

[NSGraphicsContext saveGraphicsState];

[[NSGraphicsContext currentContext] setCompositingOperation: NSCompositeSourceOut];

[shadow set];
[[NSColor whiteColor] set];
[inner fill];

[shadow set];
[inner fill];

[NSGraphicsContext restoreGraphicsState];

This is my final result. It looks pretty good. I had to change the shadow to White @ 1.0 Alpha to make it work. Even though the shadow alpha norm for menu bar items is 0.5, it doesn't look half bad.

Many thanks go out to Joshua Nozzi.

Answer 1

I think you can do this by setting clip on the bezier path to use it as a mask and stroking the shadow, then adding a normal stroke if desired.

Update based on updated code:

Here you go. I'm feeling procrastinate-y tonight. :-)

// Describe an inset rect (adjust for pixel border)
NSRect whiteRect = NSInsetRect([self bounds], 20, 20);
whiteRect.origin.x += 0.5;
whiteRect.origin.y += 0.5;

// Create and fill the shown path
NSBezierPath * path = [NSBezierPath bezierPathWithRect:whiteRect];
[[NSColor whiteColor] set];
[path fill];

// Save the graphics state for shadow
[NSGraphicsContext saveGraphicsState];

// Set the shown path as the clip
[path setClip];

// Create and stroke the shadow
NSShadow * shadow = [[[NSShadow alloc] init] autorelease];
[shadow setShadowColor:[NSColor redColor]];
[shadow setShadowBlurRadius:10.0];
[shadow set];
[path stroke];

// Restore the graphics state
[NSGraphicsContext restoreGraphicsState];

// Add a nice stroke for a border
[path setLineWidth:1.0];
[[NSColor grayColor] set];
[path stroke];