ios – 用平行线填充UIBezierPath

UIBezierPath *aPath = [UIBezierPath bezierPath];

    [aPath moveToPoint:CGPointMake(100.0, 0.0)];

    // Draw the lines.
    [aPath addLineToPoint:CGPointMake(200.0, 40.0)];
    [aPath addLineToPoint:CGPointMake(160, 140)];
    [aPath addLineToPoint:CGPointMake(40.0, 140)];
    [aPath addLineToPoint:CGPointMake(0.0, 40.0)];
    [aPath closePath];

我想用平行线填充它以使其剥离.我也希望改变这条线的颜色.
假设我想让它们垂直.
我必须以规律的间隔计算这条路上的某些点,我该怎么做？

我发现这个UIColor colorWithPatternImage然后我不能改变我的线条内部形状的颜色和“密度”.

- (void)drawRect:(CGRect)rect
{
    // create a UIBezierPath for the outline shape
    UIBezierPath *aPath = [UIBezierPath bezierPath];
    [aPath moveToPoint:CGPointMake(100.0, 0.0)];
    [aPath addLineToPoint:CGPointMake(200.0, 40.0)];
    [aPath addLineToPoint:CGPointMake(160, 140)];
    [aPath addLineToPoint:CGPointMake(40.0, 140)];
    [aPath addLineToPoint:CGPointMake(0.0, 40.0)];
    [aPath closePath];
    [aPath setLineWidth:10];

    // get the bounding rectangle for the outline shape
    CGRect bounds = aPath.bounds;

    // create a UIBezierPath for the fill pattern
    UIBezierPath *stripes = [UIBezierPath bezierPath];
    for ( int x = 0; x < bounds.size.width; x += 20 )
    {
        [stripes moveToPoint:CGPointMake( bounds.origin.x + x, bounds.origin.y )];
        [stripes addLineToPoint:CGPointMake( bounds.origin.x + x, bounds.origin.y + bounds.size.height )];
    }
    [stripes setLineWidth:10];

    CGContextRef context = UIGraphicsGetCurrentContext();

    // draw the fill pattern first, using the outline to clip
    CGContextSaveGState( context );         // save the graphics state
    [aPath addClip];                        // use the outline as the clipping path
    [[UIColor blueColor] set];              // blue color for vertical stripes
    [stripes stroke];                       // draw the stripes
    CGContextRestoreGState( context );      // restore the graphics state, removes the clipping path

    // draw the outline of the shape
    [[UIColor greenColor] set];             // green color for the outline
    [aPath stroke];                         // draw the outline
}