ART 269 3D Animation Fundamental Animation Principles and Procedures in Cinema 4D

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1 ART 269 3D Animation Fundamental Animation Principles and Procedures in Cinema 4D Components Tracks An animation track is a recording of a particular type of animation; for example, rotation. Some tracks (Property Tracks) are automatically created when keyframes (see below) are recorded in the process of creating an animation; others (Special Tracks) have to be created before keyframes can be recorded. Both types of track can be added through the Create menu of the Timeline. Tracks are listed under object names on the left side of the Timeline. Sequences Sequences are individual sections of animation located within a particular track. Every sequence will consist of at least two keyframes. Normal Keys Keys, or keyframes, are recordings of object properties at distinct moments in time. The first key in a track determines the beginning of an animation; the last key determines the end of an animation. Keys are represented in the Timeline as vertical blue (when deselected) or orange (when selected) boxes. The distance between any two keys determines the rate of change in an animation: The greater the distance, the more frames and the slower the change; the smaller the distance, the less frames and the faster the change. Master Keys Parent (master) keys, depicted as outlines, have themselves no key value and serve only as handles/selection assistants. A master key will be created in the parent hierarchy for each key you create for a given track. When a master key is selected, all keys of child hierarchies located at the exact same time in the animation will also be selected. When normal keys are selected, corresponding master keys higher up in the hierarchy are also selected, but not the keys of other tracks belonging to the parent. Master keys may be used to adjust all of the keys of an object s child tracks. Curves Curves determine the interpolation of change between neighboring keys. They are controlled and defined using tangents. The angle and length of these tangents determine the resulting curve. You can use curves to adjust velocity, acceleration (ease out), deceleration (ease in), and direction (see Timing and Curves below). In the image above and to the right you can see the animation represented as a thin, red, curving line. 1

2 Animation Recording Methods NOTE #1: If you need more frames for an animation choose Edit Menu -> Project Settings -> and change the Maximum setting. NOTE #2: For all object-based (i.e. objects in the Object Manager) animation Object mode must be selected (rather than Modeling mode). The Attributes Manager Any property that can be animated has an empty black circle next to it in the Attributes Manager. CONTROL + click on the empty black circle to create a keyframe for that particular setting. A track will also be created automatically. a) Drag the Timeslider to the desired point in your animation. b) CTRL + click on the empty black circle of the setting for which you want to set a key. c) Drag the Timeslider to the next desired point in your animation and edit the setting s value. d) CTRL + click on the circle again. CTRL + click: Create and delete keys The Animation Palette The Animation Palette is used to create and play back keyframe-based animation. 1. Keyframing in Conjunction with the Record Function 2

3 The icons shown above are located in the Animation Palette. The left-most icon (key symbol) records the current properties for all selected objects at that time in the animation and creates corresponding tracks and keys automatically. a. Drag the Timeslider to the desired point in your animation. b. Edit the object property to be animated. c. Click the Record button. d. Repeat a-c to record additional keys. 2. Autokeying (automatic recording) Next to the Record button you will find a button with two circularly bent arrows. Activate this button to turn on the Autokeying mode. When in this mode, all object properties will be recorded without having to manually click on any button. a. Drag the Timeslider to the start point for your animation. b. Edit a given object s properties. c. Drag the Timeslider to the next point in your animation. Tracks and keys will be created automatically. d. Repeat b-c as necessary. Don t forget to deactivate the Autokeying mode when you have finished working on your animation; otherwise you may end up overwriting the entire animation you just created or creating additional animations you do not need! 3. Reversing Animation Sequences Unfortunately, this function is not implemented very well in current versions Cinema 4D. a. In the bottom part of the Animation Palette Timeslider, click and drag over the keys to be reversed so that they appear orange. b. Control-click or right-click in the Timeslider rule to bring up the contextual menu. c. Select Edit -> Reverse Sequence. d. The animation will now run in reverse. 3

4 The Timeline If you want to create an animation track manually for a given item, select the item in the Timeline and locate the setting or option you want to animate in the File -> Add Property Tracks menu. A corresponding animation track will be created and keys can be added using CTRL + click. Key values can then be edited in the Attributes Manager. Changing Duration and Direction Lengthening/Shortening Animation You can lengthen an animation in the Timeline, Attributes Manager, or Animation Palette. NOTE: You must have enough frames in your Timeline to lengthen your animation. If you need more frames choose Edit Menu -> Project Settings -> and change the Maximum setting. In The Timeline window: To change the end point of a sequence: Drag the last key to the left/right; any intermediary keys will remain in their current position. 4

5 To scale a sequence (using the Functions menu): 1. Select the first key. 2. Shift-click on the last key. 3. Choose Functions menu -> Move/Scale. 4. Set a Scale value based on the amount of time you wish to add to your animation. Values of less than 1 will shorten the animation. 5. Click on the OK button. To scale a sequence (manually): 1. Select the first key. 2. Shift-click on the last key. 3. In the area beneath the time ruler, drag the right side of the orange selection range to the left/right. To move a sequence: 1. Select the first key. 2. Shift-click on the last key. 3. Choose Functions menu -> Move/Scale. 4. Set a Move value based on the amount of time you wish to add to your animation. 5. Click on the OK button. To insert additional frames into a sequence: 1. Select the track you wish to modify by clicking on its name in the left column of the Timeline. 2. Choose Functions menu -> Insert Frames 3. Add From = the frame at which new frames will be added. 4. Add Count = the number of new frames to add. To remove frames from a sequence: 1. Select the track you wish to modify by clicking on its name in the left column of the Timeline. 2. Choose Functions menu -> Delete Frames 3. Delete From = the frame from which frames will be removed. 4. Delete Count = the number of new frames to remove. 5. Select Ripple Mode so that the frames to the right shift to the left. 5

6 To create simple looped sequences: 1. Create an animation in which the first and last keys have the same Key Values. 2. Select the track name on the left of the Timeline. 3. In the Attributes Manager change the After setting to Repeat. 4. Set the number of Repetitions you need. 5. Your track will now loop for the number of repetitions your set. NOTE: You must have enough frames in your Timeline to complete your loops. If you need more frames choose Edit Menu -> Project Settings -> and change the Maximum setting. Timing and Curves The Timeline provides two different ways of looking at animation: Key Mode and F-Curve Mode. You can unfold (display) a track s mini f-curve by clicking on the small black arrow before the track name, but it is easier to work with f-curves in F-Curve Mode. F-Curve is short for function curve. They are also sometimes referred to as interpolation curves (because they control the progression from one key to the next). Flat curve segments indicate slow or no movement; steep curve segments indicate fast movement. a) To switch to F-Curve Mode you click on the second icon at the top left of the Timeline. b) To view the f-curve for your animation select your animation track name on the left of the Timeline. c) To frame the f-curve in the Timeline (so that you can see it in its entirety) choose Frame menu -> Frame All. Your animation will appear as a thin colored line with the keyframes represented as small colored squares (the colors will vary based on the animation track type). As with Key Mode, time runs from left to right, so the horizontal scale represents the evolution of your animation over time. The vertical scale, which is exclusive to F-Curve Mode, represents the Key Value a numerical value based on the type of animation track. For example, for a recording of the y position of an object, the vertical scale would represent the actual y position of the object; for a Bend deformer, the vertical scale might represent the Strength of the bend. In the image above, the red line is the f-curve for the Position.X track; the blue squares are unselected keys; and the orange square a selected key. The black lines emerging from the orange key are its tangents that control the shape of the curve and, therefore, the interpolation of the animation between the keys. In interpreting this curve, we would say that the position of the Sphere object starts at over 200, drops to 0, and then rises to 200 again at the end of the animation. This curve shows soft 6

7 interpolation for the keys, meaning that any sudden changes have been eliminated. Spline Interpolation is applied by default to all animation tracks that have associated f-curves. Straight line segments would indicate linear interpolation and changes from key to key without any speeding up or slowing down (easing). The following keys can be used when editing tangents (SHIFT also works in conjunction with CTRL and OPTION): SHIFT: Tangents will be broken; left and right tangents can be edited separately. CTRL: Only the tangent length can be edited. OPTION: Only the tangent s angle can be edited.! Use of F-Curves 1. Acceleration (Ease Out of a frame) a. Select key in the Timeline. b. Choose Key menu -> Spline Types -> Ease Out 2. Deceleration (Ease In to a frame) a. Select key in the Timeline. b. Choose Key menu -> Spline Types -> Ease In 3. Deceleration/Acceleration (Ease in to frame Ease out of a frame) a. Select key in the Timeline. b. Choose Key menu -> Spline Types -> Ease Ease 4. Changing Direction a. Create an animation. b. Select the key at which you want to create a change in direction in the Timeline. c. Rotate the tangents so that the right tangent points down and the left tangent points up for an animation moving in a positive direction or rotate the tangents so that the right tangent points up and the left tangent points down for an animation moving in a negative direction. The image above shows a Position.X track animation for a Cube, with three keyframes. The middle key has its tangents rotated so that the right tangent is pointing down and the left is pointing up. The curve shows an animation of a Cube 7

8 moving in a positive x direction, reversing to a negative x direction at around frame 20, and then moving in positive x again at around frame 55. Note that the red curve dips below 0 in around frame 46. This means that in this animation the Cube reverses past its start point. NOTE: The horizontal scale is Time; the vertical scale is the Key Value (the property changing in the animation). Objects and Materials that Animate Automatically NOTE: Keyframes do not have to be recorded for this type of animation, though the must be used to create variations in movement. a) Shaders: Many material shaders (such a Noise and Water) have built-in animation properties. Look for a property, such as T Frequency, that lets you adjust the speed of movement. Setting this value to 0 should prevent animation from occurring when you need a static texture; increasing the value will cause quicker movement. NOTE: You will only see shaders animate after rendering is complete always make test renders so that you can confirm the speed of movement. b) Arrays: The Array object has built-in properties that can be set to create vertically oscillating animations. Amplitude [ m] = The maximum movement in the Y direction. Frequency [ ] = Determines the rotational wave velocity (speed of movement). You may use point value for slower movement Array Frequency [ ] = Defines the number of waves. This setting should not be greater than the number of copies in the array. If this setting is equal to the number of copies each copy will appear to move independently. c) Wind Deformer: Generates waves on an object. The wind blows in the deformer s positive X direction. Drag the orange handle on the Z-axis to change the amplitude of the waves interactively in the viewport. Drag the orange handle on the X-axis to change the size of the waves in the X and Y directions. Amplitude [ m] = Scales the wave function in the Z direction, and the turbulence function in the Y direction. To change the value interactively, drag the orange handle on the Z- axis. Size [ m] = Scales the deformer in the X-axis and Y-axis. Increasing this value will have the effect of increasing the frequency of the waves. If the Flag option is checked, Size will also cause a more abrupt change in the size of the X-axis envelope. Frequency [ ] = Determines the speed of the waves. Turbulence [0..100%] = Adds secondary waves in the X direction, with amplitude in the +Z direction. In addition, Turbulence adds a wave in the Y direction, with amplitude in the +Z direction. The percentage defines the size of these secondary waves relative to the main waves. fx [ ] /!fy [ ] = Determine the frequency of the waves in the X and Y directions. Flag = If you enable this option, all points along the deformer s Y-axis remain still (fixed). For example, you can use this to simulate a flag on a pole one end of the flag flaps freely in the wind, while the other end is fixed to the pole and does not move (place the deformer s Y-axis along this end of the flag). 8

9 d) Emitters: Are particle systems are used to generate multiple identical objects that follow a defined path emitted from a single object. They are often used to create effects such as smoke, fire, and schools of fish. All particle systems usually consist of three parts: an Emitter, which "emits" the particles; the object to be emitted as particles; and a modifier, which determines the how path the emitted particles follow will be modified or redirected. Particle systems are a very powerful feature but often add significantly to rendering times. Emitter Settings - Particle Tab Birthrate Editor - number of particles created per second in Editor Birthrate Renderer - number of particles created per second in final rendering Visibility - used to animate how many particles are visible in a particle stream Start Emission - when the particle stream will begin emitting objects Stop Emission - when the particle stream will stop emitting objects Seed - ensures a particle stream is unique in pattern when several particle streams are used in the same animation Lifetime - how long particles are visible in frames. Variation - a percentage by which you can deviate from the Lifetime setting. Speed - how fast the particles move (in units per second). The larger to setting, the longer the particle lines appear in the viewport. Variation - a percentage by which you can deviate from the Speed setting. Rotation - angle of rotation for revolving particles. Variation - a percentage by which you can deviate from the Rotation setting. End Scale - end size of particles relative to their start size (1 is normal size; 0.5 is half size; 2 is twice as large). Variation - allows for a deviation percentage particle sizes at the end of the animation. Tangential - used for curving the particle path when the emitter is moving through a curve (cannot be used in conjunction with rotate and very memory intensive). Show Objects - displays particles as real object instead of as lines (slows down the redraw rate). Emitter Settings - Emitter Tab Emitter Type - shape particles emit in (either Pyramid or Cone) X-Size - horizontal size of emitter Y-Size- vertical size of emitter Angle Horizontal - horizontal angle of particle emission Angle Vertical - vertical angle of particle emission 9

10 Example: A radial emitter that spreads out particles uniformly would be set to: Emitter Type = Pyramid X-Size and Y-Size = 0, Angle Horizontal = 360 Angle Vertical = 0. Modifiers Attractor - a radially symmetrical gravitational force. With this modifier you can capture particles in a similar way that the sun captures individual planets. You can also create water whirls with this function. Deflector - deflects particles. A realistically animated billiard table could quite easily be created with just five deflectors (one for the surface plus four cushions). The emitter creates just one particle (a sphere for the ball) that never leaves the table, rebounding off the cushions. (Elasticity changes the angle of deflection). Destructor - enables you to destroy (i.e. remove) particles from the particle stream. Particles are affected by the destructor if the origin of their local axes lands within the boundaries of the destructor (the size of the particle object plays no part here). Friction - slows down a particle stream to a given degree (Friction). Gravity - imbues a particle stream with gravitational force (Acceleration indicates the strength of gravity negative values reduce normal gravity). Rotation - imposes a velocity vector in the XY plane of the modifier that is always tangential to a circle whose radius connects the particle and the modifier s Z-axis. This rotation occurs around the Z-axis of the Rotation modifier. Turbulence - continually assigns random velocities to the individual particles. Interesting effects can be made with an elongated modifier, resulting in twisting effects such as smoke. Wind diverts and disrupts particle streams to one side at a given Wind Speed. 10