索具的艺术

Animator Friendly Rigging —— III. Example I – Bouncy Ball ( 1 )

2007-04-20T00:02:00.000+08:00

Animator Friendly Rigging —— III. Example I – Bouncy Ball ( 1 )

Animator Friendly Rigging

Creating animation rigs which solve problems, are fun to use,and don’t cause nervous breakdowns. ——Jason Schleifer

To demonstrate how important analyzing the needs of the rig are to creating a production-quality control structure, let’s take a look at one of the most simple examples: a bouncing ball.

Figure 1 – The ball. A ball rig is seemingly simple, but can get complicated rather quickly.

If I were to simply say to three riggers, “create me a bouncy ball rig”, I would get three different animation rigs. Maybe none of which would meet my exact needs. For example, how bouncy should the ball be able to be? What kind of material is it made of? What are the rules?
By speaking with animators before creating the rig, you can set up certain “rules” or guidelines as to how the rig should work. This will save you time and energy by producing only what is necessary.

Steps 1, 2, 5, 7, and 32 – GET SOME REFERENCE!
For the bouncy ball, let’s take a look at the requirements, both animation and rig-based. The animation requirements will be based on what the animator and director want to be able to do with the bouncy ball—how they want it to move around, to act, to interact with it’s environment.
The rig requirements will be a combination of standard requirements (i.e. easy to use, etc) and specific requirements for this particular creature or object. Of course, the best way to determine these requirements is to do exactly what an animator does: get some reference. You can’t be certain of the way an object should move or what it should be able to accomplish without actually seeing or thinking about it performing the way you want. So for a bouncing ball, if you have a ball available get it out and start bouncing it around. This will give you direct experience with the ball, which will help you determine what you need to have it do. If the ball is meant to just bounce up and down, we’ll have to add the ability to move it around (Figure 2).

Figure 2 – moving the ball up and down

What if the ball is supposed to be a bit rubbery? In this case, we’ll need to squash it when it hits the ground, and perhaps stretch it out a bit while it’s moving through the air (Figure 3) .

Figure 3 – adding squash and stretch

Now this would be a pretty boring animation if the ball just bounced up and down, so we probably need to add the ability to travel around horizontally a bit as well. However, if we can do this, then we’ll need to be able to angle the stretch and squash to make sure the ball stretches along the angle of movement (Figure 4).

Figure 4 - allowing the ball to stretch along the path So far this allows for quite a bit of animation control.

What if the animator decides they want to bounce off of something that isn’t the floor? Like a wall? In this case, it is important for us to allow the ball to squash against any surface (Figure 5).

Figure 5 – Allowing the ball to squash against any obstacle, no matter what angle it is.

This is a pretty powerful rig! However, it’s not quite finished. What happens if the ball has a texture on it? We’ll need to rotate the ball in order to make sure it’s moving properly. One really important note with this.. we need to be able to rotate the ball independently from the direction it’s stretching. If the ball rotation and stretch-ation (it’s a word, honest) are tied together, it will always look like the ball is physically jumping from spot to spot instead of rotating naturally.

Figure 6 - In drawing A, the ball is angled to follow the path that it’s moving. This makes it appear as if it’s jumping from spot to spot. In drawing B, the ball rotates naturally. The stretching is completely independent of the rotation.

动画师合适的索具——III.例子I — 弹性球( 1 )

2007-04-19T22:52:00.000+08:00

动画师合适的索具 ( 翻译：w.hao )

建立的动画索具，能解决问题，被愉快的使用，并且不会导致精神崩溃。
——贾森

III. 例子I — 弹性球
示范分析索具的需要对建立一个生产质量控制结构多么的重要，让我们看一下最简单的例子之一：一个有弹性球。

图1球。一套球的索具好象简单，但是接下来的演示将很快的使它变得错综复杂。

假如我仅仅简单的对三个索具装配师说，“给我建立一个有弹性的球的索具”,我将获得三套不同的动画索具。或许每一个都不能满足我实际的需要。例如，球的弹性如何？它由哪种材料做成？规章是什么？再建立索具之前，通过与动画师交谈关于索具应该如何工作，你才能建立确信的规则指南。这将仅通过必要的生产环节来节省你的时间和精力。

参考步骤 1，2，5，7，32
让我们看一下，对弹性球的动画和基础索具的规定。动画的规定是由动画师和导演决定如何处理来回弹跳的弹性球包括弹性球的移动轨迹，行为，以及与所处环境的交互。索具的规定是标准规则的结合（例如：易于使用，等等）以及这种特定的生物或者物体的具体的规定。当然，动画师完全确定这些规则的最好的方法：获取一些参考。你必须经过实际观察才能确定目标真实的移动轨迹以及是否按照你想要的方法执行。因此如果要做一个来回弹跳的球的动画，你可以取出一个弹性球来玩耍，玩得高兴点，让它在周围弹跳。观察弹跳的球将给你直接的经验，这将帮助你确定它做什么。
如果球刚刚在两点位置弹回，我们必须在它相反的方向增加阻力。（图例2）

图例2 — 球的来回弹跳

如果球应该有点橡胶的特性，怎么办？这样的话，当它从空中掉落的时候，可能向外伸展一点形状，当它落地的瞬间，我们需要压扁它。（图例3）

图例3 — 添加挤压和伸展

现在假如球刚刚从顶部或地面回弹，这将是相当令人厌烦枯燥的动画，因此我们或许需要在水平方向增加一点变化。我们需要球沿着运动轨迹的角度来伸展并压缩。（图例4）

图例4 — 允许球沿着运动路径的角度伸展

目前为止考虑到相当多的动画控制。但如果是动画师想要球碰到并不是地板的东西弹回来怎么办。像是一堵墙这样吗？这样的话，我们允许球碰到任何表面都会挤压变形是至关重要的。（图例5）

图例5 — 允许球不管什么角度碰到任何障碍物都会发生挤压变形。

这是一套相当强大的索具！不过，它还没有完全完成。如果给球赋予一种纹理材质，将会发生什么？我们需要旋转球来确保它能正确地移动。有个很重要的要点是球的旋转是独立于球的伸展变形方向。即球的旋转与伸展变形方向无关。如果球的旋转和伸展变形动作是一致的，球的运动看起来永远像从一点机械的跳到另一点而没有自然旋转。（图例 6）

图例6 — 在图A中，球沿着运动的轨迹偏移角度。这使它看起来似乎带着正从一点机械的跳到另一点。而在图B中，球在跳跃的过程中自然的旋转。伸展变形完全独立于旋转。

Animator Friendly Rigging ——II. DEVELOPING AN ANIMATOR FRIENDLY RIG

2007-04-16T23:32:00.000+08:00

Animator Friendly Rigging

Creating animation rigs which solve problems, are fun to use,and don’t cause nervous breakdowns. ——Jason Schleifer

II. DEVELOPING AN ANIMATOR FRIENDLY RIG
Creating a great animation rig isn’t as simple as just adding a series of controls and handing it off to the animator. I’ve found that the best way to solve the problem is to really think about it in a logical way, not just technically, but also artistically. What works as the best “technical” situation, may not always work for the animator. Conversely, what the animator wants may not always be technically feasable.

Developing the Guidelines
What are the guidelines for how you should determine what’s important about how a rig should work? There are two sets of requirements that you must always pay attention to:
• Animation Requirements
      • How the character should act – what does the director want? What kinds of movements will the animator need?
      • What does the character need to be able to do?
• Rig Requirements
      • Standard animation Rig Specs – these are standards that you must follow to ensure consistency with all the animation rigs.
      • How does the animator want to work with the rig.

Solving the Problems
You will have to answer questions and solve problems in order to achieve the requirements specified. The best thing you can do is develop a system that makes it easier to solve these problems. I like to use the following steps:
1. Analyze the problem – what are you trying to solve? What is the expected result? Is it similar to any other solution you’ve come up with before? How can you take advantage of previous solutions? What is the trade-off between functionality and speed? Does it really solve the problem or create other problems?
2. Create a test of the solution – Don’t try and solve the problem elegantly yet, just figure out a way to get it to work correctly and give you the result you’re looking for. It doesn’t have to be fast, it just has to work.
3. Analyze the solution – is this the best workflow for the animator? Is the solution clean? What other problems does it introduce? Are they fixable? What is the best control structure?
4. Re-create the solution cleanly – try and remove any extra steps and nodes. Consolidate everything to the bare minimum. Make sure there is nothing “extra” needed. Ensure that every node and expression is necessary.
5. Re-create again, this time using code that is easy to modify. Document each step so you can easily modify the steps if necessary. Also, take advantage of an “object oriented” approach.. i.e. make sure that everything is done in a way that it can be re-used again. * Note: This is not always necessary, but it can be extremely helpful if you ever need to create that rig again!

动画师合适的索具——II. 开发一套动画师友好的索具

2007-04-16T22:57:00.000+08:00

动画师友好的索具 ( 翻译：w.hao )

建立的动画索具，能解决问题，被愉快的使用，并且不会导致精神崩溃。 ——贾森

II. 开发一套动画师友好的索具

      创建一套索具并不是增加一系列控制并把它交给动画师这么简单。我已发现解决问题的最好的方法是从技术上和艺术上是否真的合乎逻辑的方式来考虑它。怎样工作才是最科学的工作，可能不总是按动画师的需要工作。相反，动画师想要的可能从技术上是不可行的。

开发指南

必须要注意的两个要求：
      * 动画师的要求
            * 角色应该怎样行动——导演想要角色做什么？动画师需要怎样的运动？
            * 角色需要做什么？

      * 索具的要求？
            * 标准的动画索具——所有的动画索具必须符合统一的标准。
            * 动画师想要索具怎样一起工作

解决问题

      为了达到指定的要求，你必须回答问题并且解决问题。你能做的最好的事是开发一个使解决这些问题更容易的一个系统。我喜欢使用以下步骤：

1. 分析问题 —— 你尝试解决什么，期望的结果是什么？他类似于你以前已经得到的其他解决方法吗？你怎样利用以前的解决方法来解决这个问题？在性能和速度的平衡之间的抉择是什么？他真的能解决问题还是会制造其他的问题。

2. 创建一个试验性的解决方法 —— 不需要去想多么完善的解决方案，仅要想出一个能获得你需要的结果的正确工作的方法。它不必多么快速，当它必须是能够工作。

3. 分析解决方案 —— 这是给动画师最好的工作流程吗？这个解决方案是最简洁的吗？它将带入其他的什么问题？它们是固定的吗？最好的控制结构是什么？

4. 重建这个解决方案的简洁方案 —— 想办法去除任何额外的步骤和节点。把一切巩固到最低限度的最小量。确定没有什么额外的需要。保证每个节点和表达式都是必要的。

5. 再次重建，这次使代码容易修改。为每次步骤建立文档以便能容易的修改步骤。此外，利用原始物体的优势是…例如确保任何事情可能再次被重新使用的方法重做。* 注意：这不总是必要，但是如果你需要再次建立那套索具，它可能是极其有帮助！

Animator Friendly Rigging —— I. INTRODUCTION

2007-04-16T01:23:00.000+08:00

Animator Friendly Rigging

Creating animation rigs which solve problems, are fun to use,and don’t cause nervous breakdowns. ——Jason Schleifer

I. INTRODUCTION

There is at least one indisputable fact known to animators all over the world:
achieving quality animation with a substandard rig can cause more heartache,
headache, hair loss, and general insanity than trying to run a marathon backwards
in flip-flops while tossing jellybeans into your mouth.Imagine you’re driving a car and every
time you turn the wheel to the right, the windshield wipers go off. Then you turn the wheel to the left and the car accelerates. When you press the gas—the stereo gets louder. When you try and change stations, the car reverses slowly.Sure, you could eventually drive somewhere, but the frustration that would ensue would be sure to make your life a living hell.. and in fact, you’d probably never want to drive again. A good animation rig, on the other hand, will work the way you expect. The controls will make sense, be easy to understand, placed in a location that you
expect, and work in a consistent manner. A rig that has been created with the animator’s needs in mind, will be a joy to work with, and allow the animator to think more about their performance and less about how to wrestle the darn thing into submission. But What is Animation Rigging? Simply put, animation rigging is: A process by which an “object” is made ready for animation. This means that animation rigging is the act of taking any object, character,
prop, anything that the animator is going to animate, and making it possible for them to move around and set keyframes. Notice that the definition above states objects instead of characters. It’s easy to forget that anything the animated character has to pick up and move also needs to be set up for animation by the rigger. You can liken an animation rigger to a Marionette Maker. A person who builds marionettes creates a puppet, attaches strings to the arms, head and body, and then attaches those strings to little bits of wood. They prepare the puppet to be moved around by the puppeteer. An animation rigger does not have to be a puppeteer, but they do have to understand what a puppeteer needs in order to create a believable performance.

Your role as an animation rigger is to balance:
1. The performance requirements of the character or prop.
2. The manipulation/interaction needs of the animator.
3. The technical requirements of the character or prop.

Many times, these needs will conflict with each other. For example, imagine you have an extremely realistic creature that is being animated, but the animator wants to be able to stretch the character’s body in a physically impossible way in order to make the pose read from the camera angle. What do you do? Provide non-realistic animation controls that may break the rig? Tell the animator “no, you can’t do that”? That’s your job, to determine what exactly is possible and to balance the positives and negatives of each situation. Of course, as an animator I would say that my needs were more important than any silly biomechanical necessities of the skinning rig. Important Criteria for Each Animation Rig In order to create the best rigs possible for any production situation, it is important to figure out exactly what problems you’re trying to solve before just throwing solutions at them. The choices you make in determining how your

animation rigs work should all meet the following criteria:
• Consistent/Predictable behavior
• Simplified control structure
• Easy to use
• Fast interaction
• Minimal counter-animation
• Solve the problem
• Allows the animator to do their job without compromising their ideas.

If these criteria aren’t met, the rig will not work as the animator expects, and will cause frustration. Animating is hard enough without having to fight the tool every step of the way.

动画师合适的索具——I. 介绍

2007-04-16T01:17:00.000+08:00

动画师合适的索具 ( 翻译：w.hao )

建立的动画索具，能解决问题，被愉快的使用，并且不会导致精神崩溃。
——贾森

I. 介绍

       至少有一个无可争辩的事实为全世界的动画师所知：用一套低于标准的索具制作高品质的动画将是令人无法忍受的痛苦。想象你正驾驶一辆汽车，每当你把这个车轮转向右边时，挡风玻璃上的刮水器离开。然后你把这个车轮转向左侧，汽车加速。当你按油门时，立体声变得更响亮。当你尝试开动车子时，汽车缓慢倒退。当然，你能最终开车在某处，但是将接着发生的挫折将一定使你的生活像在地狱…结果，你或许永不想要再次开车。一套好动画装置，一方面，将按你期望的方式工作。操纵装置将有意义，容易理解，安置在你期望的并符合工作习惯的一个位置。按照动画师需要建立的索具，将和动画师愉快的合作，让动画师专注于提高动画的性能。

什么是动画索具？

简而言之，动画索具是：
       “对象”准备动画的一个过程。

       这表明动画索具是通过设置”对象”的关键帧的运动来确定”对象”的行为，”对象”是动画师用来制作动画的任何事物，可以是任何物体，角色，支撑物…
你可以将一个动画装配工比拟为一个牵线木偶制造者。牵线木偶制造者建立一个木偶，在臂，头和身体中附上线，然后在控制用的少量木头上附上那些线。这个木偶将随着操纵木偶的人运动。一名动画装配工不必是一个操纵木偶的人，但是他们确实必须理解一个操纵木偶的人为了造成一次可信的表演需要什么。

作为一名动画装配工将协调：
       1. 角色或支撑物的性能需求。
       2. 动画师的操作/ 交互的需要。
       3. 角色或支撑物的技术要求。

       很多时候，这些需要将彼此抵触。例如，想象你有一种极端逼真的动物正被制作动画，但是为了让人从摄影角度观看姿势，动画师想要以一种违反物理的不可能发生的方式伸展角色的身体。你做什么？提供非现实动画控制可能打断索具。告诉动画师那时不能作到的。那么你的工作对确定什么是可行什么是不可行，并且协调两种可能性。