Problem

Solid Working Area Accuracy Information

Version: 08.00.01.19
Product: MicroStation V8
Area: Parasolid,

Solution

Information:
The solid modeling kernels require coordinate data at a fixed precision.
In order to guarantee enough precision is available, MicroStation
defines the solids working area (SWA). The SWA is effectively a design
cube centered around the center of design. The length of the cube's
edges can be found under

- V8i: Settings > Design File > Working Units >
Advanced > Working Areas > Solids,

- CONNECT Edition: Settings > File > Design File Settings > Working Units > Advanced Settings > Edit > Working Areas > Solids.

The purpose of the SWA value is to reduce the working volume to a more
manageable size when working with solids. This also increases the
accuracy for solids. Maximum accuracy for solids can be achieved by
setting the Resolution to 1,000,000 per Meter and setting Solids to 1
Kilometer.

How much accuracy is required depends more on the size of the smallest
detail (blend , etc.) rather than the size of the solid itself. Because
of this, it is difficult to give a definitive answer and also depends on
the types of operations that are planned on being done and on what
types of geometry.

Less accuracy is required for Boolean operations on orthonginal (square)
elements vs. dealing with a lot of complex blends on B-Spline surfaces.
The precision needs to at least cover the smallest detail, but somecalculations.

Conclusion:
The Solids Working Area can be changed, and there is a lot of
flexibility there, but the optimal setting is when the SWA is 1 km (to
match the ParaSolids modeling kernel accuracy).

Notes:
Changing the SWA value does not change the Resolution, that is the size
of elements in the file will not be changed.
It is operations in ParaSolid may require more precision for the internal
possible to move ParaSolid elements out of the SWA, but they
will not be able to be modified until returning with the SWA.
The SWA is centered about the center of the design area, not the global
origin.

Not applicable to V8i based products

See Also