Tangential

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Panchdara
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Tangential

Post by Panchdara » Fri Apr 12, 2019 8:32 am

Using 3.22.0.5 - can someone give me a lesson on using the Tangential tool? I just seem to fall flat on my face when attempting to use it.

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Tangential.jpg
Tangential.jpg (35.88 KiB) Viewed 5569 times
Windows 10

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Husky
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Re: Tangential

Post by Husky » Fri Apr 12, 2019 9:18 am

That will be a very short lesson ..... :wink:
The tool is meant to draw a line - landing tangential on an arc, circle or ellipse.

Start point - where ever you need it.
End point will snap tangency on an arc, circle or ellipse.
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Panchdara
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Re: Tangential

Post by Panchdara » Fri Apr 12, 2019 10:03 am

Thanks. But I still think there is a bug. I want to draw a line tangential to a circle. Say, 45deg. I draw the circle then choose the angular line (choose middle) and try and make it tangential to that circle - complete fail. :?:
Windows 10

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andrew
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Re: Tangential

Post by andrew » Fri Apr 12, 2019 10:21 am

Panchdara: I can see that this is tempting, but the tangential snap tool does not work this way (and is not designed to work this way).

The only situation where this snap is useful is for drawing a line from a point tangential to a circle:
- Draw > Line > Line from 2 Points
- Click start point of line
- Click Tangential snap (as indicated in your screenshot)
- Click circle or arc

The tangential snap snaps to the tangent point of an imaginary line from the relative zero point (small red circle with cross) to the clicked arc. For all other situations, use the specialized tangent drawing tools or auxiliary constructions.

The reason behind this behavior is that snap functions are unaware of the tool you are using and are designed to work consistently across all tools. A snap function does not know that you are about to create a line with a given angle nor is it aware of that particular angle.

Panchdara
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Joined: Wed Nov 25, 2015 4:15 pm

Re: Tangential

Post by Panchdara » Fri Apr 12, 2019 10:35 am

Thanks Andrew. It's just that the tangential tool is available when in angular line mode. That seems to have messed me up. Also, sometimes I see "tangential" as a snap point sometimes - when, I can't seem to replicate. So, for me to make a tangential angular line to a circle, I first create the circle, then draw an arbitrary line at the given angle. Then create a perpendicular line to that angular line and then move that created perpendicular line to the center of the circle and redraw the same angular line at the intersection of the circle and perpendicular line - is that correct? I'm so dazed and confused. But a great learning experience - thanks to Husky and his 52 circles :D
Windows 10

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J-J
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Re: Tangential

Post by J-J » Fri Apr 12, 2019 12:44 pm

You can use orthogonal trough point, point being the center of your circle. you may then move your arbitrary line to the intersection of your perpendicular and circle
JJ Win7 pro-64

Panchdara
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Re: Tangential

Post by Panchdara » Sat Apr 13, 2019 8:50 am

Thank you JJ. That works a treat also... such a simple solution that I feel a little embarrassed to have had a brain f@rt. :oops:

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Hugh
Windows 10

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