Need to find line that's perp to another and also passes through a point

Hello: I'm currently working with .net api and using Autocad 09 mechanical. I have a point and a line and I need to find another line that's perpendicular to the line and also passes through the point (see pic - red line represents line I'm looking for. The point and the other line are given).

I need to find this line programmatically.

Thanks,

Proctor

Take a look at:

curve.GetClosestPointTo(pt,false)

that looks like it might help....let me give it a try.

thanks,

Proctor

then again, just because it's the closest point on the line to the point doesn't mean it's going to be perpedicular like i need. mmm

Proctor

then again, just because it's the closest point on the line to the point doesn't mean it's going to be perpedicular like i need. mmm

 

Proctor

I think you'll find it will be :wink: by the laws of Euclidean geometry and all..

If you're working with lines it sure will

I just bought a book on geometry...I need to brush up on it.

ok, let me give this a try. I'll get back to you.

thanks again,

proctor

Good one Lee never thought of that as you say a circle will only touch the line at one point and it is true perpendicular.

Just a side you can always use basic geometry to calculate it as well its pretty easy as you have a perp answer. You just need to know the angle of the line and calculate the angle & dist from an end of line to the picked point the rest is sin cos tan.

Just a quick one Lee do you have pick a point near a line end draw perp then move new line to the end of exsiting line variation of this request. Option 2.

Good one Lee never thought of that as you say a circle will only touch the line at one point and it is true perpendicular.

Thanks, quite a few of my programs use this law.

Just a quick one Lee do you have pick a point near a line end draw perp then move new line to the end of exsiting line variation of this request. Option 2.

Once you have the picked point, you then have the perpendicular point, and hence the angle/distance between the two, so your options are endless

Lee Mac: I've been working with curve.GetClosestPointTo(pt,false) and it appears to be working! thank you for telling me about this.

Also, thanks to everyone for their inputs.

Proctor

Lee Mac: I've been working with curve.GetClosestPointTo(pt,false) and it appears to be working! thank you for telling me about this.

 

Also, thanks to everyone for their inputs.

 

Proctor

You're welcome Proctor