Models

A model is a group of one or more brushes to which programmers can attach data, and level designers can animate or point to from entities. There are two primary reasons to create a model: to create a moveable piece of geometry that you can animate; or to create a piece of geometry that programmers can identify at program run-time in order to provide special effects when an operation involves that piece of geometry.

For example, you might make a level that contains several different pools. By making each pool into a model and pointing entities at those models, the programmers will be able to differentiate among the pools. If they weren't models, then they'd be treated like any other piece of geometry and be indistinguishable from each other.

To create a model, selecte the brushes that you want to make up the model, and then from the Models Options page, click on the Add Model button. The program will prompt you for a model name. Once you've entered the name, the program creates the model. You can add brushes to a model by selecting those brushes, selecting the desired model in the Models page, and then clicking on the "Add Brushes" button. Other buttons on the Models page allow you to select and deselect all of the brushes in a model, remove brushes from a model, delete a model, clone a model, and set the model's rotation origin. The bottom half of the Models page allows you to define an animation path for the model.

You create a model's motion by defining its keyframes--points through which the model will move--and the time it should arrive at each keyframe. When animating the model, the engine interpolates between keyframes to provide smooth motion. The simplest motion is one with a single keyframe. The model will move in a straight line from its original position to that keyframe in the time that you specified when you created that keyframe. Motions with multiple keyframes work in much the same way, but the animation engine provides interpolation that moves the model smoothly from one keyframe to the next without abrupt direction changes (i.e. it "rounds the corners").

To create a motion for the model, select the desired model from the drop-down list on the Models page, and then press the Animate button. The editor will select the model's brushes and put the editor into Move mode. You can then move and rotate the model to the position you want the model to occupy at its next keyframe. When you have it at the position you want, press the Stop Animating button and enter the keyframe time.