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Animation Overview

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Model Setup for Animation

So your object is modeled, you've surfaced it and set it up in a scene and added lights. The next step is to bring it to life with animation. In order to ensure the smoothest animation workflow in MODO, there are a few basic concepts one should understand before proceeding. The first and most important is the difference between components and items. MODO has a number of selection modes for editing meshes- 'Vertices', 'Edges', 'Polygons' and 'Items'. In most default layouts, these modes are displayed across the top of the screen, right under the menu bar. It often looks like this-

modo modes bar

MODO modes

Hitting the space bar on your keyboard will toggle through the first three modes -'Vertices', 'Edges' or 'Polygons', these are the component modes and this is where geometry is built. When in these modes, applying any type of transform action- position, rotation, or scale, you are editing the raw geometry that makes up the mesh layer. You might have noticed that regardless of where you position the geometry in the layer, the 'Center' position for that Item in the Properties panel will always read '0' for each axis. This is because component edits are modifying the contents of the layer. Now if you select the 'Items' mode, and apply the same transforms, you can see the Properties values are changing as you are now transforming the layer as a whole. This is called an Item level transform and this is where objects are animated (and positioned*). It can occasionally be confusing as the same tools for Move, Scale and Rotate are used for transforming items in both the component and Items modes, but if you keep an eye out for which mode you are in, it will very soon become second nature.

Mesh Layers as Items

When modeling objects it is convenient to think of Mesh items as layers, especially when using tools like booleans that use the background/foreground layering concept for doing its operations as well as layer used for retopology using Background Constraints. Some users will keep every single element in its own layer and use groupings in the Items list to keep things organized, while others will merge elements keeping everything tidy in a single layer. However you prefer to work, MODO is quite flexible, but keep in mind that each individual mesh layer is its own object in MODO's mind. Each has its own settings and controls in the Properties panel, its own center and pivot points, and its own set of vertex maps (disabled layers won't show up in the Lists viewport). Anything that need to move independently from another will need to have its own item layer. If you take for instance a car model as an example, the body would need to be one layer, and the four wheels would each need to be their own independent layers. And depending on how detailed you wanted to get, you could also make the doors and the hood and trunk objects their own layers as well, so they could rotate to open as well.

Transform Items

MODO uses a layered approach to working with item transforms that has several benefits over a traditional system. These are the channels that define the Rotation, Position and Scale properties of any item. When you first create a new Mesh item, before applying any transforms to it, you can switch to the 'Channels' viewport and see that when first created there are no transform channels present. The input fields are visible in the Properties panel, but until a value is assigned, the channels themselves do not exist. What you will see are the options 'Add Position', 'Add Rotation' and 'Add Scale'. Users can manually add them, but anytime a users transforms an item, the channels are created automatically.

Where things get really interesting is when users start to add more than one. The additional transforms are fired in the order that they are listed in the Channels view, bottom to top, so users can control how the item is placed, oriented and sized in the scene based on the order of its Transform Items. The benefits of such a system are that it is very flexible, users can apply complex motions by simply assigning a few additional Transform Items, also they are light in that MODO only adds the channels that are necessary. For scenes with thousands of items, it can produce significant savings in file size and processing not having to deal with any unnecessary channel data, and lastly they keep the items list clean, where all the transforms are tucked away under the single item. In a traditional system, the same result could only be achieved by parenting multiple Null items together and animating each one individually, creating additional unnecessary items.


If we take in to consideration the car example from earlier, with the individual mesh items having been successfully created for the make-believe car, how does one move the whole thing around in the scene? It's far too cumbersome to select each individual item in the viewport or item list, it's also prone to errors. To ensure all the elements remain together when moving the cars, we need to create a hierarchy. Hierarchies are groups of items that define how each element relates to other elements. Creating hierarchies are covered more fully in both the Item List and Animation Setup documentation sections. For simplicities sake here, we can just create the most basic MODO hierarchy - a group. By selecting all the elements of the car and using the keyboard shortcut 'Ctrl-G', we have placed all the mesh items into a group (folder icon in the item list). If one wants to easily move the entire car and have its individual parts follow along, one just needs to select the top most group item (in this case, the group Locator) and apply a transform to it, all the related items in the group will follow along. Another benefit of creating a hierarchy is that it nicely organizes the Items list, especially important when building up complex scenes..

Centers and Pivots

MODO provides two methods for setting the point around which an item rotates and scales, 'Centers' and 'Pivots'. You may be familiar with pivots from other applications; MODO's pivots can be used in the same manner. However, MODO also provides 'Centers' which in the many situations are used instead of pivots. Before proceeding though, we need to be able to see the Pivots and Centers, as they are not visible for all viewports (this is a 'per viewport' setting). To do this, open the 'Drawing and Visibility' options for viewports by hovering the mouse over the target viewport and pressing 'O'. In the popup, select the 'Visibility' subtab and see the options for 'Show Centers' and 'Show Pivots'.

Center Pivot Vis

Setting them to 'Selected' will show a layers associated Center or Pivot whenever it is selected in the Items list, 'All' will always display them regardless of selection, but for scene with many items, their display may become overwhelming. So, now that we can see them, lets look at their definitions-

Center: This is the local origin of the model and the default location around which item transforms originate. It's the location that sits at the world origin (0,0,0) when all the item transforms are at their defaults, i.e. when the item has not been moved, rotated or scaled in 'Items' mode. Centers cannot be animated relative to the element they represent, but adjusting their location allows you to set where the item will rotate and scale from.

Pivot: Pivots also provide the ability to specify the location around which an item will rotate and scale, determined as an offset from the Center (When adjusted you'll see a small dotted line draw between the Center and the Pivot as a reminder). They can be used when one needs to animate this location (say a cube rolling across the floor for example, where the rotation point jumps to each edge as it rolls), as Centers cannot be animated. Once a Pivot is moved (defining that offset from the Center), the rotation and scaling occurs around this position instead of the Center.

So, the only real difference between them is that Pivots can be animated and Centers cannot. This is because the pivots are an offset from the Center (Pivots animate relative to the Center). In most cases Centers are perfectly fine for animating items, this is why they are the default method.

Now again still considering the prior car example, if the entire object were modeled in a single layer, then the individual mesh items were then created by copy/paste functions from layer to new layer for the tires and doors. Now while each item has its own 'Center', the default location for each one is in the same location at the world origin. If you were to try to animate the cars tires to roll at this point, you would find they don't rotate as one might expect, they probably rotate from a point originating somewhere under the center of the vehicle, sending the tire out into giant crazy circles; centers don't default to the center of the geometries bounding box. So users will need to position the Center itself to the correct location relative to the tire. The alternative could have been to have modeled the tire separate from the car at the origin, and then use an Item level transform to then move the tires to the proper position relative to the car body but luckily MODO doesn't care how the item was created and can easily reposition the Center point independently, without affecting the geometry itself.

Center Icon

If one RMB+clicks over the 'Items' selection mode button, a popup appears allowing for some alternate mode selections. By clicking on 'Center' you are now in a mode that allows you to edit the location of Center positions without affecting the location of the original geometry in any way. So, by making sure the tire mesh item is selected in the item list, we can now see a small circle with the three lines coming out from it, this icon represents the center of our items layer. By clicking on the center icon itself (the white circle), it will turn orange, showing that it has been selected, now the 'Move' (W) and 'Rotate' (E) transform tools will affect the Center point. You could move it and eyeball it into the center of the wheel, or you could use a trick with the Work Plane that is much more precise.

Switching back for a moment to 'Polygons' selection mode, there should be some type of selection that could be made that would represent the position from where the wheel should rotate from, make this selection and use the 'Align Work Plane' command from the menu bar "Edit > Work Plane > Align to Selection". Now switch back into 'Center' mode and select the center again. In the 'Animate' and 'Setup' interface tabs there is a command called 'Set to Work Plane', click it, and that will move the Center to the origin of the Work Plane which was precisely aligned to the center of your previous polygon selection. Reset the Work plane by pressing the 'End' key and everything is back to normal, but the Center was precisely positioned with no guessing or eyeballing required (For more information on the Work Plane, please reference that page of the documentation). Now when one animates the tire, it will rotate around the proper location. Just like in modeling there is a process to getting the best results, animation requires a bit of setup, but once one understands the basic setup techniques, it eventually becomes quick and easy.


Animating Workflow

Once the model is set-up (also referred to as rigging for more complex setups), you are ready to start animating. Making anything occur over time in MODO requires a keyframe. A keyframe simply sets a specific value for an elements in time, be it a position, or a surface setting or whatever. Nearly any setting in MODO can be keyframed to change over time. In traditional 2D cartoon animation, artists draw the important poses for an animated sequence, and then another artist, called the in-betweener, draws all the subsequent frames that transition from one pose to the next. Animating in 3D is very similar, where users set up the key poses (or positions, or settings) but unlike traditional animation, MODO takes care of all the in-between frames for you.

In MODO the general workflow is to select the type of element you want to work with and then run a tool or fire a command that will affect your selection. Select a vertex, activate the move tool, move it, that kind of thing. Keyframing is similar in MODO, in this case the type of 'things' you are working with are channels. Channels are simply the animateable properties of any item.

When you press the 'Key' button ('s' shortcut key in Items mode) MODO needs to know which channels you want to create keys on. It does this by using channel selections, it runs through each channel you have selected and creates a keyframe on that channel at the current time. Selecting channels can be done in a couple of ways, by clicking on them in a 'Channels' viewport or by clicking on the control label on a Properties viewport, (the small gray circle that precedes an attribute in the properties panel), when users click on the dot, it will change from gray to red signifying a keyframe is set at that point in time for that property.

Constantly selecting channels to keyframe would quickly become tedious so MODO provides some 'Auto Key' behaviors to help with this. These are set with the 'Auto Key' menu at the bottom of the "Animation' interface layout, next to the transport controls. The default setting is 'Animated', with this on MODO will automatically create keyframes on channels that are already animated (i.e. at least one key has been set on the channel previously) whenever the value on the channel changes. This can be by using the transform tool, using the mini-slider or by typing in a value on a forms control. If changes are made to a channel that has not been keyed the changes are still applied but keyframes will not be made. The next setting is 'All', and as it's name suggests this will create keyframes on any channel at the current time whenever it's value is changed. You have to be careful when using this setting and be aware of whether you're in animation mode or not as it's obviously very easy to create animated values when they may not be wanted. The last setting is 'None', this will never create keyframes automatically for you, to make keys you must use the 'Key' button whenever you've made changes.

Which setting you use is entirely up to the user of course, depending on how hey like to animate. Some people like auto keying, some people loathe it. The recommended setting is the default 'Animated' one, it provides a workflow somewhere between the two extremes of on and off and only requires the additional initial step of creating keys on the channels of the item you want to animate in advance.

The other area that MODO tries to help with keyframing is automatic channel selection. Auto keying only works when channel values have changed, when you need to create a set of keys for channels without changing the current values you need to use 'Key' button (which requires the channels to be selected) or individually click on the channel buttons on the properties forms. To help with this MODO will automatically select channels for you when using the transform tools, activating the move tool for example will select the position channels.

A general Auto Key workflow--

1.) Select the Camera and go to its Properties viewport.
2.) Click on the channel keying buttons for the six position and rotation channels. They should turn red.
3.) Activate the transform Move tool (W key) and move the camera.
4.) Activate the transform Rotate (E key) and rotate the Camera
5.) Move the time slider to a new time
6.) Move\rotate the Camera again
7.) Go to a new time...etc

Once those initial keys have been made you should not have to do any further manual keying unless you want to key the camera in place. This will also work when using viewport navigation to move the camera. This general overview should be enough information to get you up and animating. So, what are you waiting for? Get to it, and have fun.


* When working with Instances and Replicators, it is best to model the base mesh at the origin as all duplicated items will use that position as the transform origin when propagating duplicates. Of course, adjusting the Center position after the fact will remedy any peculiarities as well.



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