Both kinds of 3-D design software operating quite differently from each other. The first, Solidworks, allows creations to remain in a state of flux so calculations relating to a series of forms and spaces may be easily changed in view, distances can be entered as formulae devised from existing measurements within the project.
A form in Solidworks is built by first of all making a two dimensional sketch. In the 2-D sketch lines and points fit one of three descriptions: under defined, shown in green; fully defined, shown in black or over defined, shown in red. Under defined parameters maybe constrained fully defined parts of the sketch or sketch origin making them fully defined or related to other undefined parts or just left in this state of flux.
If a line, curve or point has conflicting definitions it is over defined and the software will not allow it to be extruded into a form. If measurements or relations that parts depend upon are deleted or drastically altered, then the line or point which depends upon it is said to be dangling and shows in green.
A form may be extruded perpendicularly with or without the inclusion of a draft angle of up to three decimal places applied to it or revolved from a sketch. Further sketches may be drawn onto or offset from any surface of any form. An array of tools and options are available, giving rise to all manner of creation.
Forms may be saved as parts then built up into assemblies by relating points, edges, surfaces, etc. to each other.
The software includes a varied database of renders to give a final finished effect. On the whole, after the initial head scratching period, I found this software very easy to use.
The finished article may be printed as drawings with chosen measurements shown, as a variety of fixed views for example front, left, right, rear, top, bottom, isometric, dimetric or trimetric, or rotated to any position from a fixed perspective.
Rhino on the other hand requires that clear definitions in terms of X, Y & Z are made from the outset and alterations are not so permissable, although parts may be constructed then combined and moved together or seperately, but again only in terms of X, Y & Z As far as I can tell there is no way to reference Part A to Part B and formulae can not be used, for example, a piece of funiture can not be set to reference other parts in the project the only way to reference any part is in terms of X, Y, & Z with respect to the origin, so you have to know where the parts are in order to reference other parts to them. The split screen facility is absolutley essential to this end.
I do think this is a cheap alternative, however, once you get used to it Rhino is quite a versitile program. The point of perspective may be altered to give much more realistic views and I found that adding renders was very simple.
