A category for Sparrow that draws rounded lines via SPTexture and Core Graphics.

SPTexture+Line.h

//
//  SPTexture+Line.h
//  Sparrow
//
//  Created by Shilo White on 8/3/13.
//

#import "SPTexture.h"
#import "SPImage.h"

@interface SPTexture (Line)

- (id)initWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded;
- (id)initWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded padding:(float)padding;
+ (id)textureWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded;
+ (id)textureWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded padding:(float)padding;

@end

@interface SPImage (Line)

- (id)initWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded;
- (id)initWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded padding:(float)padding;
+ (id)imageWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded;
+ (id)imageWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded padding:(float)padding;

@end

SPTexture+Line.m

//
//  SPTexture+Line.m
//  Sparrow
//
//  Created by Shilo White on 8/3/13.
//

#import "SPTexture+Line.h"

@implementation SPTexture (Line)

- (id)initWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded
{
    return [self initWithLineLength:length width:width rounded:rounded padding:0.0f];
}

- (id)initWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded padding:(float)padding
{
    return [self initWithWidth:width+(padding*2) height:length+(padding*2) draw:^(CGContextRef context)
            {
                float halfWidth = width/2.0f;
                float capWidth = rounded ? halfWidth : 0;
                
                CGContextSetLineWidth(context, width);
                if (rounded) CGContextSetLineCap(context, kCGLineCapRound);
                
                CGContextMoveToPoint(context, halfWidth+padding, capWidth+padding);
                CGContextAddLineToPoint(context, halfWidth+padding, length-capWidth+padding);
                
                CGContextSetStrokeColorWithColor(context, [UIColor whiteColor].CGColor);
                CGContextStrokePath(context);
            }];
}

+ (id)textureWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded
{
    return [[self alloc] initWithLineLength:length width:width rounded:rounded];
}

+ (id)textureWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded padding:(float)padding
{
    return [[self alloc] initWithLineLength:length width:width rounded:rounded padding:padding];
}

@end

@implementation SPImage (Line)

- (id)initWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded
{
    return [self initWithLineLength:length width:width rounded:rounded padding:0.0f];
}

- (id)initWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded padding:(float)padding
{
    return [self initWithTexture:[SPTexture textureWithLineLength:length width:width rounded:rounded padding:padding]];
}

+ (id)imageWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded
{
    return [[self alloc] initWithLineLength:length width:width rounded:rounded];
}

+ (id)imageWithLineLength:(float)length width:(float)width rounded:(BOOL)rounded padding:(float)padding
{
    return [[self alloc] initWithLineLength:length width:width rounded:rounded padding:padding];
}

@end