Incorrect radius value.

Antondeg

I create an arc with a Radius of 5M on my drawing. Then when I read that value through Ruby I get either a value of 196 or 180 and I am not sure of the units. The length is also wrong. I find the edge then I get the curve off the edge then I get the radius from the curve.


entity.curve.radius.to_s

Any ideas how to get the correct value?

thomthom

All angles from SketchUp is in radians.
All lengths are in inches - and comes as a Length object (subclass of Float)

There are helper methods to deal with this:

Use .radians and .degree to convert between angle and radians.
http://code.google.com/apis/sketchup/docs/ourdoc/numeric.html#radians
puts entity.curve.angle.radians.to_s

When you have a Length and want to display it to the user, just rely on Length.to_s to present the length in the model units.
http://code.google.com/apis/sketchup/docs/ourdoc/length.html
puts entity.curve.radius.to_s

Make sure you know if you have a Float or a Length object - make use of the Length class, don't try to convert between other units unless you need to present anything to the user. Remember that a Length converted to float returns the length in inches as that is the system unit for SketchUp.

TIG

@antondeg said:

I create an arc with a Radius of 5M on my drawing. Then when I read that value through Ruby I get either a value of 196 or 180 and I am not sure of the units. The length is also wrong. I find the edge then I get the curve off the edge then I get the radius from the curve.

entity.curve.radius.to_s

Any ideas how to get the correct value?

How are you setting the radius to "5m" ?
You must use 5.m or equivalent?
When you get the radius in code it's in inches so entity.curve.radius.to_m.to_s will return a string with it in meters.
In Entity Info it shows in 'current units'.
The 'length' of an arc given in Entity Info [or code] is the accumulative length of the arc's individual segments in current units - the more segments an arc has the nearer it is to the real length of a 'true' arc.
To calculate the true length of an arc find it's swept_angle=end_angle-start_angle [which is automatically in radians] and then use
length = 2*Math::PI*radius*swept_angle/(2*Math::PI) = radius*swept_angle in inches
If it's a circle [i.e. edge.curve.is_polygon?] then use
length = 2*Math::PI*radius
TIP: to check if a Curve is an Arc, and therefore it can have a radius use
edge.curve.typename=="ArcCurve"

Antondeg

Thanks once I used to_m I got the correct value.