Essential Blender- P2 potx

And now you have a pretty (or not) picture of your model. That's great, but what good is it? Well, for many uses, architectural visualization, making fake product shots for marketing campaigns, doing artwork for personal enjoyment, it is enough. A nice still image is the end. But, for many others, this is not the end of the process. You might need things to move. It could be as simple as moving the camera around your model to show off your hard work. If you wanted to really show off, you might make the models of trees appear to sway gently in the wind and have the striped pole on the barbershop spin slowly. Then, a car speeds down the road. Chased by a huge boulder. Chased by a giant, three-headed robot. That's animation. Animation In CG, there are basically three ways to create motion. The first is to tell certain objects (like a car) where to be, and at what time. Essentially, you say: "Car, I would like you be at this side of the street when I start rolling the camera, and over at the other end of the street three seconds later. Can you handle that?" And the car says: "Dude, I'm not real! I'm not even constrained by the laws of physics. I can do anything you want!" And you say "Awesome!" because it really is. Animating by telling things where to be and when to be there is called Keyframing. Each rendered image that makes up part of an animation is called a Frame. And so, to animate with this method, you go to a Frame (that's the "when") and set a Key (that's the "where") for the location of the object. To make the Car example a little more technical, you would go to Frame 1 in your 3D application (the start of the animation), use the application's tools to put the car at the beginning of the street, and set a Key. Then, you would move the application's time counter three seconds ahead in time, move the car to the end of the street, and set another Key. Rendering all of the images that represent those three seconds of time, then playing them back in sequence, will show the car moving from the beginning of the street to the end. The second division of animation, Character Animation, is really just keyframe animation - the same basic procedure of telling "where" and "when" is used - but as it requires a different set of skills, it is usually thought of separately. What kinds of different skills? Well, the method of animation we just discussed is good for moving objects around that don't change shape. It's pretty straightforward: the object starts here, goes somewhere else, and ends up over there. Maybe it topples over onto its side. That is considered "object level" animation, and more or less, anyone with half of pint of imagination and visualization skills can pull it off. Character animation is different. Some people might think that character animation is most akin to the clay and model based stop-motion animation popularized in a glut of Christmas specials and sometimes bad/sometimes brilliant motion picture and television features. Not so. Let's Talk About Art Don't expect Blender, or any other 3D application for that matter, to substitute for a lack of artistic knowledge and skill. 3D applications are tools, and nothing more. In the hands of a skilled artist, they can produce moving pieces of art. In the hands of a hack, they will produce junk. Even if you have no artistic background though, all is not lost. There are some basic rules for creating artwork that can be gleaned from a simple web search or a trip to your local library. In my experience, 3D art is an interesting combination of photography and illustration. From photography, you take the techniques of lighting and composition. From illustration (painting, drawing, etc.), you take all of the artistic decisions of working in a non-realistic medium. In other words, at some point you have to decide what portions of reality you will try to reproduce, and what portions you will omit or only suggest. For a better example of what I am talking about, use as a reference any of the 3D animated feature films produced in the last five years. None of them could be said to be completely photorealistic. In other words, reality does not look like those films. And yet, as we watch them, we are drawn into their shorthand for reality, and our minds fill in the blanks. It turns out that your toughest job as a 3D artist is exactly that: decide which portions of reality you will omit or imply, and which portions you will recreate. The rest is mechanics. Character animation is a combination of technical skill, imagination, acting ability and puppetry. Yes. Puppets. There is a reason that a certain high-profile animation studio's in- house character package is called "Marionette". A well set up system of controls for character animation will react more like a complex puppet than anything else. In Blender, the structure that controls character animation is called an Armature. Armatures can resemble skeletons: Figure 1.19: An armature skeleton appropriate for character animation. Or something a bit more esoteric: Figure 1.20: The "Ludwig" rig by Jason Pierce. The odd shapes floating over the head are the face controls, which act exactly like the controls on the large-scale multi-operator puppets used for motion picture and television special effects. But those skeletons and additional controls still function under the same principle as object- level keyframe animation. Place the Arm bones where and when you want them and set a Key. Move the eyebrow controllers to make a goofy face at the right frame and set a Key. Play the whole thing back and each bone and controller will hit their spots at the times you told them to, making a (hopefully) brilliant character animation. The clever armature and controls move the (equally brilliant) model you've already built of a person, causing it to not only move from place to place, but to change shape as it does so. This change in shape is called Deformation. Figure 1.21.1: A rig in rest position with a character mesh around it. Figure 1.21.2: When the rig is posed, the mesh follows. None of this is limited to human beings, though. You could make an armature that was just a chain of four bones, attach it to a model of a soda can, and keyframe the armature so that the soda can wriggles around on the ground like worm. Or hops about like a kid jazzing on four bars of high-test chocolate. The third method of animation is called Simulation or Procedural Animation. Those are just different ways to say "the computer figures it out for you." All natural processes, like a block wall collapsing on itself or the motion of poured water splashing into a glass, are governed by the laws of physics and can, with a greater or lesser degree of success, be simulated by a computer program. Often, as in the case of water splashing into a glass, a computer can do a much better job of animation than a human being can, because it can actually simulate the physics of the situation. The same applies to a falling wall of blocks or a flag flapping in the wind. Since these are physical simulations, you have to tell your CG application the basics about what you're simulating, which usually include values for gravity, elasticity, mass, wind, etc. Figure 1.22.1: Rigid Body Physics: A block wall in mid-tumble. Figure 1.22.2: Fluid Simulation: Water pouring into a glass. Figure 1.22.3: Soft Body Physics: A flag in the wind. In addition to built-in simulations like these, (Blender has rigid body physics - think bowling balls falling down stairs; soft bodies - think an overweight stomach jiggling when slapped; and fluid simulation built right in) many 3D applications, including Blender, allow you to write little programs (usually called Scripts) that can control and generate animation. These can be as simple as a script that makes objects follow the contours of the ground, or as complex as full applications that can produce and animate large-scale battle scenes. Figure 1.23.1: Objects littered around a terrain by a script. Figure 1.23.2: A large-scale combat simulation. Conclusion . create motion. The first is to tell certain objects (like a car) where to be, and at what time. Essentially, you say: "Car, I would like you be at this side of the street when I start rolling