Just Keep Rigging
Character rig animation can be one of the most challenging aspects of motion graphics we are faced with. For anyone unfamiliar with animation, a character rig is like giving your illustrated character a skeleton, to unify the movement of its features. It's what links or 'parents' the hand to the wrist, the wrist to the forearm, the forearm to the body and so on.
Once these ‘bones’ are in place and parented up, it will give you an easier form of control, like stringing up a puppet! When you move the hand upwards, the arm will bend and raise with it, whilst still connected to the body. Using rigs will simplify your work-flow and bring characters to life in a more believable way.
Introducing Rubber Hose...
Today there is a higher visual expectation for animated characters than ever before; so there’s more pressure to create smoother rigs and fluid movements. It can be time consuming, and frustrating to get your rigged character moving correctly, and this is where plug-ins become essential to help you with the process. With Adobe’s After Effects there are a number of plug-ins available to help you set up character rigs. DUIK has always been of the best, offering a full range of rigging capabilities, and it’s available for free from duduf.net.
The problem I find with DUIK is it can be a little overwhelming and time consuming to implement the steps of a full rig. It involves pinning joints, creating bones, creating controllers for those bones and controllers for those controllers. Confusing right? Sometimes you'll want to generate a quick rig for some basic movements without all that hassle. Well, a recent addition to animation scene is 'Rubber Hose' from BattleAxe, and it's a brilliant solution for simple rigging. Take a look at the short promo video below for some great examples of what this plug in can achieve.
Rubber Hose provides a straight-forward rigging solution to generate characters that bend and stretch effortlessly. But let’s be clear, Rubber Hose is not a complete rigging tool set. There are a number of limitations, where traditional rigs would be better suited e.g. dealing with multiple joints or animating facial expressions. Rubber Hose simply provides a quick and easier way to generate functional limbs which you can control with a number of variables such as length, sharpness of the bend, and bend direction.
Bending & Stretching
Let’s look at an example. Below is a standard ‘Hose’ generated by the plugin with the click of a button. With any hose, there are two end points which act as controls, these can be key-framed to change the shape of the hose. As the points get closer together, the hose will start to bend.
The angle and size of the bend can be adjusted using the effect settings. Take a look at the image below and notice how the control points are static, but a bend is occurring. So what's happening here? The length of the hose is being altered in the effects panel;and as the length increases, the size of the bend gets bigger because there is more 'give' between the two control points. In reverse, a decreased length will tighten the hose between the points, causing it to straighten. When the distance between the controls is less than or equal to the length of the hose, the guide markers will turn from yellow to blue. At this point the hose will start to stretch. This colour code is a useful signal to help you adjust your effect settings correctly.
Now let's look at how parenting works with Rubber Hose. Connecting an asset or additional hoses is really simple and works like any other parenting process. Simply select the asset you want to attach, drag it into position and select the parent layer from the parent drop-down menu in your layers panel. Now when you animate the parent layer, any layers connected to this layer will move with it. The example below shows how a hand can be parented to a hose, notice how the hand automatically pivots in sync with the bend of the arm.
Ok we get it, they bend and they connect. But how do we turn the preset grey hose into something more illustrative? This is all done through path styling. Open up the contents of your hose layer and navigate to Style > BaseHose > Stroke. This expanded menu will give you a list of options which will affect the appearance of the hose. You can change the hose width, colour, opacity, dash and stroke cap options, which can be layered for some interesting results! Take a look at my example below.
The transformation of this hose can be broken down into 4 Basehose style layers.
- Layer 1: Here I changed the grey stroke to black
- Layer 2: I added a layer with a larger stroke size and a trim path offset to the centre.
- Layer 3: I duplicated Basehose layer 2, changing the colour to yellow and reducing the stroke size.
- Layer 4: Finally I added a yellow stroke thinner than Basehose Layer 1, to create an outlined effect.
A common problem users face with other rigging tools, is the limited ability to change the look of asset source-files once they have been rigged. For example changing the size, resolution or shape of a character’s arm could dislodge it from its body and this is what we refer to as a broken-rig. This might be ok if you're the Picasso of animation, but for other designers this has always been a hindrance. Rubber Hose doesn't rely on the same IK calculations as other rigging tools, so resizing and restyling mid-work won't risk breaking your rigs!
There are an endless amount of styling options, and you'll find you can quickly build suitable limbs to fit your character. The image below is the end result of using my two example hoses above, with some illustrated features parented to the control points.
Once you understand the principles of styling and rigging in Rubber Hose, you'll be able to generate animations that bend and flex with a polished finish. It's a user-friendly tool full of creative potential that will benefit your work-flow, and for $45 it's great value for such a practical plug-in. I found it takes away many of the technical obstacles from animating, leaving you with the fun stuff. It's the easiest and most enjoyable way to get those legs walking, arms waving and hips thrusting!
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