.NET

## .NET

Active Contributor
Posts: 42
Registered: ‎07-02-2013
Message 1 of 7 (158 Views)

# block on curve

158 Views, 6 Replies
07-17-2013 10:41 PM

Hi,

I am trying to move a block on a curve with reference to 2 points on the curve.I am facing problem when one point is on horizontal part of curve and other point is at an angle.How do i place the block at angle.Please help.

Valued Mentor
Posts: 311
Registered: ‎04-11-2010
Message 2 of 7 (127 Views)

# Re: block on curve

07-18-2013 02:19 PM in reply to: gulzar25

Hi,

You can obtain the angle from the first derivative of the curve at that point, and calculate the rotation angle from that angle.

Gaston Nunez

Active Contributor
Posts: 42
Registered: ‎07-02-2013
Message 3 of 7 (122 Views)

# Re: block on curve

07-18-2013 07:37 PM in reply to: gasty1001
Hi,

Thanks
Gulzar
Valued Mentor
Posts: 311
Registered: ‎04-11-2010
Message 4 of 7 (113 Views)

# Re: block on curve

07-19-2013 06:04 AM in reply to: gulzar25

Hi,

The first derivative of a curve is the slope or tangent in a point of a curve, the function/method GetFirstDerivative returns a vector3D with Dx,Dy,Dz components , if your curve is planar, there is no need for Dz, so the tangent=Dy/Dx then theta=math.atan2(Dy,Dx), another method is to calculate the angle from X axis to the derivative vector. GetFirstDerivative should be a method for every object that inherits from the curve class. Try the docs on this topic.

Gaston Nunez

Active Contributor
Posts: 42
Registered: ‎07-02-2013
Message 5 of 7 (69 Views)

# Re: block on curve

08-01-2013 03:49 AM in reply to: gasty1001

Hi,

I tried using the GetFirstDerivative method but i couldnt get direction.Can you please help me with sample code.

Thanks

*Expert Elite*
Posts: 787
Registered: ‎04-27-2009
Message 6 of 7 (58 Views)

# Re: block on curve

08-01-2013 06:28 AM in reply to: gulzar25

When you said "move block along...", did you mean you want user to drag a selected block/entity and when the mouse cursor is dragged, the block/entity moves along a given curve?

If so, one of my articles may be of help:

Active Contributor
Posts: 42
Registered: ‎07-02-2013
Message 7 of 7 (45 Views)

# Re: block on curve

08-01-2013 10:00 PM in reply to: norman.yuan

Hi Norman,

Thanks for the reply.Yes im moving block along a curve but im moving it with respect to 2 points.Im finding it difficult to get the direction.How do i get in which direction should i move.Any ideas??

Thanks

Recently Solved