Direct modeling overview
Direct modeling is much like sculpting on-screen: just like a sculptor starts with a lump of clay or a piece of stone or wood, you start with a base volume, which is then further detailed by adding, removing and deforming geometry. All operations are executed dynamically, and you decide whether to define dimensions intuitively or by specifying values. Unlike history-based modeling, the order in which features are created is not important. All operations are performed in interactive mode: the intermediate result of an operation shows dynamically, according to user input defined by mouse movement.
A key feature of direct editing capabilities provided by BricsCAD consists in preserving the design intent. 3D dimensional constraints (Distance, Radius, and Angle) imposed for faces and edges give you full parametric control over the solid model. Different configurations and scales of the model can be obtained simply by changing the parameter of a dimensional constraint. Geometrical constraints (Coincident, Tangent, Parallel and others) define how these changes influence the geometry of the model. However, there is no need to specify all geometrical constraints manually since most of them can be recognized automatically by setting Design Intent Recognition options.
Another feature of Direct Editing operations is that they can be easily applied with the Quad cursor menu. This tool provides a set of operations based on the currently selected or previewed entity or selection set. At the same time the Quad provides the other basic solid editing operations such as copy, union and subtract.
Direct modeling operations apply to all ACIS solid geometry, whether created in BricsCAD or imported. When the separately licensed BricsCAD Communicator is installed, the IMPORT command supports all major 3D model formats, both industry standard and proprietary formats.
Depending on the value of the DELOBJ (Delete Entity) system variable, the defining entities are either retained or deleted or you are prompted whether to keep or delete the source entities (see table below).
Value | Result |
---|---|
0 | Retain defining entities |
1 | Delete profile entities; retain paths and guide curves |
2 | Delete all defining entities |
-1 | Prompt to delete profile entities; retain paths and guide curves |
-2 | Prompt to delete all defining entities |