View Full Version : Curves Need Tangency Control

11-11-2003, 12:25 PM
If there's one area of LightWave that is in desperate need of an update, it's the creation of splines and curves.

By far the biggest annoyance is the lack of ability to create 'straight sections' to curves (Fig1) when using points and 'Make Open Curve'.

For accuracy it's easier to position points in 3D space than use the Bezier/Spline Draw tools.

But when you 'Make Curve' it always insists on curving through points that should be straight (Fig1).

There is a 'trick' to straighten the section in question (Fig2) which involves selecting the curve in poly mode, then selecting the point(s) near the section to be straightened, then using the 'Add Point' tool, click somewhere after the point selected.

However this screws up the Rail Extrude making the trick useless (Fig3).

Either the Make Curve tool needs to look at the points more closely and figure out which sections should be straight or more control should be given to straighten out the sections that should be.

The Bezier tool would be better if it were kept 'live' until you froze it. It would also need to allow you to add / remove points along the path while still in this live state to be really useful.

Maintaining tangency of curves is basically the issue here (Fig4 & Fig5).

This kind of feature is essential for product designers wanting to use the Modeler for this kind of work.

I live in hope! :)


11-11-2003, 01:13 PM
Wow, solidworks is looking salubrious these days...

That is the nature of splines though...

Even Solidworks cant do this operation on one element, it takes an arc and two lines, calls them a 'profile' and extrudes from there, the same has to be done with LW for now, it just takes more steps.

A simple Piping plugin would be very handy, select a series of two point polys (like sasquatch hair guides), enter an inner radius and an outer radius in the numeric panel and a level of smoothing on the corners and go... (ther is one commercially available, but I dont have it myself...)

11-11-2003, 06:17 PM
Why does solidworks look like Paint?:confused:

11-12-2003, 12:59 AM
Erm, it doesn't! Shown here is only a simple sketch, trust me it's very powerful but simple to use!


11-15-2003, 10:42 AM
I have to agree with you Matt, spline creation and editing tools would be a boon for us guys that are accustomed to the CAD world.

Over a year of messing around in LW and I'm only getting the barest essentials down. It's a *very* different way of thinking. I had come to the opinion that spline creation and editing is something that is just not used to any degree in LW.

Eventually I'll get my head around this marvelous tool and interface...

Jeffrey Everett

11-15-2003, 01:33 PM
ah yeah - give us tangency controls mawwhahahahahaaaa and hm you know a pipe tool would be cool on that you could deect the about of degrees it bent your pipe and the radius all without getting your polys inside out etc andleavingleft overs liek it does when trying to use lathe

give give give (both)