iPhone Core Quartz 1- Round Rectangle
?- (void)drawRoundRect : (CGContextRef)context {
// Drawing with a white stroke colorCGContextSetRGBStrokeColor(context, 1.0, 1.0, 1.0, 1.0);// And draw with a blue fill colorCGContextSetRGBFillColor(context, 0.0, 0.0, 1.0, 1.0);// Draw them with a 2.0 stroke width so they are a bit more visible.CGContextSetLineWidth(context, 2.0);CGRect rrect = CGRectMake(210.0, 90.0, 60.0, 60.0);CGFloat radius = 10.0;// NOTE: At this point you may want to verify that your radius is no more than half// the width and height of your rectangle, as this technique degenerates for those cases.// In order to draw a rounded rectangle, we will take advantage of the fact that// CGContextAddArcToPoint will draw straight lines past the start and end of the arc// in order to create the path from the current position and the destination position.// In order to create the 4 arcs correctly, we need to know the min, mid and max positions// on the x and y lengths of the given rectangle.CGFloat minx = CGRectGetMinX(rrect), midx = CGRectGetMidX(rrect), maxx = CGRectGetMaxX(rrect);CGFloat miny = CGRectGetMinY(rrect), midy = CGRectGetMidY(rrect), maxy = CGRectGetMaxY(rrect);// Next, we will go around the rectangle in the order given by the figure below.// minx midx maxx// miny 2 3 4// midy 1 9 5// maxy 8 7 6// Which gives us a coincident start and end point, which is incidental to this technique, but still doesn't// form a closed path, so we still need to close the path to connect the ends correctly.// Thus we start by moving to point 1, then adding arcs through each pair of points that follows.// You could use a similar tecgnique to create any shape with rounded corners.// Start at 1CGContextMoveToPoint(context, minx, midy);// Add an arc through 2 to 3CGContextAddArcToPoint(context, minx, miny, midx, miny, radius);// Add an arc through 4 to 5CGContextAddArcToPoint(context, maxx, miny, maxx, midy, radius);// Add an arc through 6 to 7CGContextAddArcToPoint(context, maxx, maxy, midx, maxy, radius);// Add an arc through 8 to 9CGContextAddArcToPoint(context, minx, maxy, minx, midy, radius);// Close the pathCGContextClosePath(context);// Fill & stroke the pathCGContextDrawPath(context, kCGPathFillStroke);}
