A library for animated line drawing (like an invisible pencil). Allows you to declare a series of drawing steps, set the speed (points per second) and then tell it to start drawing. I'm just getting started on this library so it's very basic right now. More awesomeness to come.

Installation

In your Podfile, add this line:

pod "MTPencil"

pod? => https://github.com/CocoaPods/CocoaPods/

NOTE: You may need to add -all_load to "Other Linker Flags" in your targets build settings if the pods library only contains categories.

Example Usage

Here we create a pencil object, telling it what view to draw in. Then, we define a series of moving or drawing steps, all starting where the last one left off, then you tell it to begin drawing.

@interface MTTestView ()
@property (strong) MTPencil *pencil;
@end

@implementation MTTestView

- (void)drawPicture
{
    MTPencilSpeed speed = MTPencilSpeedVerySlow;

    _pencil = [MTPencil pencilDrawingInView:self];

    [[_pencil move] to:CGPointMake(100, 100)];
    [[[_pencil stroke] angle:MTPencilStepAngleUpRight  distance:20]    speed:speed];
    [[[_pencil stroke] angle:MTPencilStepAngleUp       distance:50]    speed:speed];
    [[[_pencil stroke] angle:MTPencilStepAngleRight distance:100]   speed:speed];
    [[[_pencil stroke] angle:MTPencilStepAngleDown      distance:200]   speed:speed];
    [[[_pencil stroke] angle:MTPencilStepAngleLeft      distance:100]   speed:speed];
    [[[_pencil stroke] angle:MTPencilStepAngleUp       distance:123]    speed:speed];
    [[[_pencil stroke] angle:MTPencilStepAngleUpLeft   distance:20]    speed:speed];
    [[[_pencil stroke] to:CGPointMake(200, 200)]                        speed:speed];
    [_pencil beginWithCompletion:^(MTPencil *pencil) {
    }];
}

- (void)drawRect:(CGRect)rect
{
    [_pencil animate];
}

@end

NOTE: You must call animate on the pencil in your view's drawRect:

Options

You can tell the pencil to draw at any degree (ie 143), but here are some predefined enums to help out:

MTPencilAngleUp         = -90
MTPencilAngleDown       = 90
MTPencilAngleLeft       = 180
MTPencilAngleRight      = 0
MTPencilAngleUpRight        = -45
MTPencilAngleUpLeft     = -135
MTPencilAngleDownRight  = 45
MTPencilAngleDownLeft   = 135

You can tell it to draw at any speed in points per second (PPS), or you can use some defaults:

MTPencilSpeedVerySlow   = 100
MTPencilSpeedSlow       = 400
MTPencilSpeedMedium     = 600
MTPencilSpeedFast       = 800
MTPencilSpeedVeryFast   = 1000