This is another wish to control faceting, especially in 3d geometry operations. Recent posts and many old ones explore the problem from several user experiences.

Extrusion, EAP, NURBS curve, NURBS surface, Shells, etc all exhibit faceting. This seems to stem from some software design interpretation of the curves. Curved geometry is generally understood by humans as an analog concept - a circle or other smooth curve is continuous. It has no vertices or facets. The curve can be defined by math. ANY point on the curve conforms to the math. Extrusion, conversion to NURBS, EAP, etc should adhere to the source curve math without creating additional corners or facets!

Digital interpretation of curves, including in vwx, is not continuous. Digital depends on plotting vertices along the analog pathway and connecting the vertices with straight segments. The end points of the segments conform to the math definition, but points between do not. (This is less apparent in 2d curves (arcs, polys), but becomes apparent in conversions and use as sources for 3d objects.) More vertices produces a smoother looking curve and less deviation from the math definition. Computers allow plotting myriad points along the analog curve. I’m guessing software (eg Vectorworks) designers decide how many points/segments, balancing performance against curvature excellence.

Here is chart with vwx 2d and 3d conversion resolutions pref set to max. It scales, so larger diameters will yield same vertex count and proportionally longer facets.

Wish - Lots more points, perhaps 2d and 3d prefs for sooper dooper stratospheric high conversion res? Or some other way to conform more closely to analog understanding of continuous curves?

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Popular Post## Benson Shaw

Popular PostThis is another wish to control faceting, especially in 3d geometry operations. Recent posts and many old ones explore the problem from several user experiences.

Extrusion, EAP, NURBS curve, NURBS surface, Shells, etc all exhibit faceting. This seems to stem from some software design interpretation of the curves. Curved geometry is generally understood by humans as an analog concept - a circle or other smooth curve is continuous. It has no vertices or facets. The curve can be defined by math. ANY point on the curve conforms to the math. Extrusion, conversion to NURBS, EAP, etc should adhere to the source curve math without creating additional corners or facets!

Digital interpretation of curves, including in vwx, is not continuous. Digital depends on plotting vertices along the analog pathway and connecting the vertices with straight segments. The end points of the segments conform to the math definition, but points between do not. (This is less apparent in 2d curves (arcs, polys), but becomes apparent in conversions and use as sources for 3d objects.) More vertices produces a smoother looking curve and less deviation from the math definition. Computers allow plotting myriad points along the analog curve. I’m guessing software (eg Vectorworks) designers decide how many points/segments, balancing performance against curvature excellence.

Here is chart with vwx 2d and 3d conversion resolutions pref set to max. It scales, so larger diameters will yield same vertex count and proportionally longer facets.

Wish - Lots more points, perhaps 2d and 3d prefs for sooper dooper stratospheric high conversion res? Or some other way to conform more closely to analog understanding of continuous curves?

-B

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