A node is a subpart of a model. Simple models just have a single node but usually a model consists of several nodes that a connected to each other. Together the nodes form a tree, also known as scene graph. There are two different node types:
- Data nodes: Stores some properties that are needed to represent the model. Usually a data node only stores a mesh and a material.
- Composite nodes: Stores nodes that can be either data nodes or other composite nodes. The nodes stored in the composite node can be thought of as being the child nodes, or just children, of that composite node. Consequently the composite node is the parent of its children. The composite node is also responsible of transforming its children to the right location in the scene.
A layer is a way to group a set of nodes. When exporting a model to Cm3D it is important to make sure that there is only one material for each layer.
The layer overview gives you an overview of all the layers in the model. Simply click on a layer to select all the nodes in that layer.
The hierarchy overview helps you understand how different parts of a model are connected. If you select a parent node all the child nodes are automatically selected. For instance, this can be useful when you want to remove multiple nodes in a single operation.
Axis Aligned Bounding Box
The axis aligned bounding box for object X, or just aabb, is the smallest box, aligned to the axis of the coordinate system, that fully encloses X. In Model Lab X usually refers to a node or the complete model.