Set end of line to meet another line without altering length

Use this forum to ask questions about how to do things in QCAD version 3

Moderator: andrew

Set end of line to meet another line without altering length

Postby wildspidee » Sat Nov 03, 2012 8:58 pm

I need to set the end point of a line based on another line without altering the length, only the angle. Here's an example:

Line A Vertical - length 28, Start 27,56 End 27, 28
Line B - length 40 Start 57,22

I need the end point of B to rest on line A at any point on line A that preserves the length of line B. I've tried moving and snapping, but I lose either my start point or length in the process. I can probably figure out the angle with math, but I'd rather have an 'in program' solution that can eventually be programmed to draw automatically. The resulting angle of B is important for the rest of the drawing.

Any ideas or suggestions are appreciated! Thank you.
wildspidee
Junior Member
 
Posts: 19
Joined: Sat Nov 03, 2012 2:00 am

Re: Set end of line to meet another line without altering le

Postby Clive » Sat Nov 03, 2012 9:41 pm

In a situation like this based on angles - arcs and circles come in useful:
1.Draw a circle - radius 40.
2.Use centre point at coordinate 57,22.
3.From intersection draw line to the centre/line start (57,22).
4.The resulting line should be exactly 40 in length.

geometry method.png
geometry method.png (18.39 KiB) Viewed 1584 times
User avatar
Clive
Moderator
 
Posts: 909
Joined: Thu Aug 25, 2011 9:28 pm
Location: UK

Re: Set end of line to meet another line without altering le

Postby wildspidee » Sat Nov 03, 2012 9:48 pm

Brilliant! The circle never even occurred to me, but that makes perfect sense. It's easily automated, too.

Thank you so much Clive.
wildspidee
Junior Member
 
Posts: 19
Joined: Sat Nov 03, 2012 2:00 am


Return to QCAD 3 'How Do I' Questions

Who is online

Users browsing this forum: Google [Bot] and 1 guest