cutting curves in polys

[Alucobond]

I'm using Max 2009.

 

The posted image shows site plan linework. the light grey area is a poly that i created for a portion of the concrete. I want to cut in the curved lines to create planters etc. What is the best way to cut curved lines into a poly? or should i consider a different solution? I will not be smoothing this.

 

Thanks

[Bruce Hart]

Hi Kevin,

there are a few ways you can do this. I keep all kerbing areas like this as spline shapes that are extruded or bevelled to produce the surface. Any holes on the surface just require attaching an interior shape to the main spline and your done. On many occasions you can simply mesh select a spline shape to make it a renderable surface and have it sit just above the main kerbing.

 

If you really need to cut a shape into a poly surface you can use shapemerge which is found under Compound objects in the create panel. Hope this helps

[Alucobond]

Thanks Bruce

 

do you use an extrude modifier on the spline? if I try to convert an unclosed spline to a poly or mesh it disappears. I have been creating a closed spline converting it to a poly and then i can extrude the edges. the problem that i found with the extrude modifier is contolling what axis i want to extrude from. could you tell me the steps you use to create your surface?

 

Thanks Again!

 

Kevin

[Bruce Hart]

Hey Kevin,

As you have found, the spline needs to be closed for capping to occur. To make a closed spline shape into a renderable poly you can use a mesh select modifier, which will produce a poly face with no thickness. This will enable you to go back and alter the spline shape to change the poly shape.

 

Attached is a screen shot of what you get if you use a bevel modifier. I'm working in metric as you can see. The fist level extrudes up 50mm and the second extrudes again 100mm with a negative outline value. This forms a 45 degree chamfer. With this method you can go back to the spline level in the modifier stack to change the base shape. Another way to make kerbing like this is to use a profile on a sweep modifier. This has the advantage of having UVW mapping along the spline.

 

If you have a spline that is extruding in the wrong axis direction, create a new spline rectangle on the plane you want (which extrudes in the direction you want), and attach the old spline to the new rectangle. You can then delete the new rectangle at the spline level, and the rest of the shapes will have adopted a new extrude axis. Then you should not need to convert to poly, but simply extrude the spline shape.

Edited June 5, 2011 by Bruce Hart