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.Program NavigationAnimation programs are so robust they cannot possibly display all theirtools and features in one screen.Consequently, some method of navigationis featured in each program.The most common method is to feature a rangeof category buttons and menus and subcategory buttons and menusthat represent ever more specific subsets of commands.For instance, a cat-egory button might be Create, and a subcategory button might be Primi-tives, and a further sub-subcategory might be Sphere.Category buttonsremain onscreen at all times.When one is clicked, an appropriate subcate-gory of buttons may appear.This is usually referred to as drilling down into a program.Other buttons may also remain onscreen at all times but are not cate-gory buttons.These pertain to functions that must always be available tothe operator, such as File and Save As.We could consider these to be con-stant buttons.Category buttons and subcategory buttons may be simply alphanu-meric (such as those in LightWave), iconic (such as many in 3ds max andMaya), or a combination of the two.Learning the various pathways of theprogram and getting to various tools when you know the program eats upa lot of operator time.As a result, program developers are always trying to 04_200505_Avg_ch04 9/5/03 11:29 AM Page 177The Mechanics of Three Leading Animation Programs177find new and easier ways of learning and operating the navigation.Moredetails are provided on each program later in the chapter.View NavigationView navigation refers to the method each program provides to manipulatewhat the views are shown.The navigation is usually done by the mouse orpointing device, often in combination with a keystroke.Although some sim-ilarities exist, each program is different.Obviously, orthogonal views cannotallow tumbles (because the tumble would redefine the view s definition),but on-axis adjustments are possible to adjust the view.Keep in mind thaton-axis moves are not camera movements (such as tilts, pans, or zooms)that imply a pivot point in the camera head.Perspective views, however, areintended to allow the operator to examine the scene from any angle or dis-tance, so full movement, including tumbling and zooming of the view, issupported.Object NavigationThe tool set for affecting objects is called the manipulators (not to be con-fused with your bosses).Today most 3-D animation programs have stan-dardized the onscreen symbols that users employ to execute objectmanipulation.Using symolic manipulators, animators may manipulate cam-eras, lights, bones, and objects.Object maniulation is the basis of animation.Although object navigation allows any object in the view to be selectedand manipulated in many different ways, object manipulation allows aselected object to be changed.Object manipulation is divided into two cate-gories: movement and deformation.Movement includes changing theobject s position on the stage and rotating the object.Deformation includesany change of the object s size, shape, or surface characteristics.The most common manipulators are move, scale, and rotate.Whenany of the manipulators are selected, an appropriate symbol appears withinthe selected object or element.The move symbol is usually composed of abox outline with three colored vector lines (usually with arrowheads at theends) representing the three axes (red X, green Y, and blue Z) emanatingfrom it.You may move the selected object freely on all axes if you click thecentral symbol, or you can isolate one axis by clicking one arrowhead at theend of that axis. 04_200505_Avg_ch04 9/5/03 11:29 AM Page 178Chapter 4178The scale symbol is similar to move, but the center symbol and the endsof the vector lines will change to indicate a different manipulation frommove.The colors of the vector lines and end symbols are the same asthose for the move tool, and they refer to the same axes as the move tool.When the center symbol is clicked, the mouse affects all three axes simul-taneously.The rotate symbol is composed of three intersecting rings (red for the x-axis, green for the y-axis, and blue for the z-axis) around a central point thatrepresents the pivot point of the object.Again, clicking the center of thesymbol allows free manipulation of all axes at once, whereas clicking anyone of the colored rings selects a single axis.It should be noted that Light-Wave tends to vary from this convention somewhat, as described later.Animation programs enable the operator to obtain a view through thevirtual camera and, in some programs, through a lighting instrument.Object navigation and manipulatins, unlike view navigation, may berecorded as keyframes at specific locations on the timeline and provide apowerful animation element.Layers and HistoriesAnimation, particularly the modeling phase, is a kind of iterative process.This means that you tend to perform a step, evaluate it, and then reiteratethe process to a finer level of detail and/or satisfaction.When satisfied, theanimator will proceed to the next task in a methodical progression.In theprocess of modeling an object, you might execute hundreds, perhaps thou-sands, of iterations.Most programs have tools for assisting this meticuliousprocess.The program can assist you by automatically recording each of your deci-sions in a list, often called a history
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