Table of Contents
3D scene visualization
GroIMP has an embedded 3d visualization view and manipulation toolkit. If the project graph contains 3d objects, or object that instantiate 3d objects, it is possible to visualize it in a scene with the 3d view.
Project graph visitation
To be displayed in the 3d scene, the project graph is visited by a DisplayVisitor (whose most common implementations are WFVisitor for the Wireframe view, and GLVisitor for the OpenGL 1 view). From the root, each Node with a Successor or Branch edge is visited. All nodes connected with other types of edges are ignored.
Additionally, to impact the 3d display nodes needs to extends Null (de.grogra.imp3d.objects.Null), which represent the Nodes with 3d transformation. Each Null object have its own local transformation (could be null). The DisplayVisitor goes through Nodes stacking their local transformation. Thus, the global transformation of an Object in the 3d scene, is the combination of all local transformations of all its parents (in the successor/branch sense).
All GroIMP module extends Null.
See more:
Instantiation rules
If a Node have a instantiation rule, it is added before its local transformation. E.g. the following code display a Sphere, then a Cylinder.
module A extends Cylinder ==> Sphere;
Produced geometry:
But instantiation rules are not included in the graph and do not modify the stack of local transformation. Yet, they have their own stack. Thus, within an instantiation rule the 3d geometry shapes follow same local transformation concept.
E.g. the following code will display a Sphere on top of a Cylinder.
module A ==> Cylinder Sphere;
Produced geometry:
