During AccuRender's model load process, all AutoCAD 3-D objects with curves are approximated by polygon meshes in a process known as tessellation. For 3-D solids, regions, and custom objects, this tessellation is handled entirely by AutoCAD. For extruded circles, extruded arcs, and thick or wide polylines with arcs, AccuRender performs the tessellation. Any translations that take longer than 5 minutes should be considered long.
Common reasons that a model may take a long time to translate are:
The drawing contains many solids.
The drawing contains cylindrical
solids (extruded circles).
The drawing contains many plants.
A drawing that is made primarily of solids can be deceptively large at rendering time. A 6 MB model in the AutoCAD can tessellate to 250 MB under certain conditions. The level of tessellation is controlled by the AutoCAD variables VIEWRES and FACETRES. If these are set too high, they over-tessellate the model. VIEWRES is the most sensitive and should always be set to its default of 100. Setting this higher causes an incredible amount of memory to be used with little improvement in quality. FACETRES defaults to a value of 0.5. A setting of 2 is suggested as a starting point. A setting above 8 is considered very high, slows performance, and is usually not required.
Cylindrical solids can also take a lot of time. If you are using cylindrical solids for something like balcony railings on a large building, you can make the railing a square section. This reduces the translation time and the difference is not usually noticable in the final rendering.
Using many plants, large trees, and groundcover can increase translation time. More than 20 trees is considered a lot. Try to use the lowest possible setting of tree possible without sacrificing quality. Also, use groundcover sparingly. You can also use bitmap backgrounds and groundcover to reduce translation times.