Hi Michael

When i use the 3 point arc tool i often use the start,on,end option and define the start and on points then use a construction line to define a mirror point to the start. So i can use that snap for the end. It would be good if that mirror point could be automatic if you hover in that area with the cursor. Hopefully the attached picture is clear.

Another way would be to be able to start at the midpoint (1) then a startpoint (2) with the endpoint automatically a mirror (3). Again a picture attached. Top option preferred though would save having to define a construction line.

Kind regards

Jamie

Hi Jamie, the part that's difficult about that is the general case of just trying to make an evenly spaced 3rd point, there are actually an infinite number of different points that could satisfy that.

For instance if drawing an arc through 3 points, with #1 below as the start point, and #2 as the "on" point:




Then there are a whole variety of different points that would make a "balanced" arc, like this:




So for the general case there isn't a good place to put a single snap point because there isn't just one solution.


I guess you may be talking about making a snap point that kind of takes the Y axis of the construction plane into special consideration so making one kind of orientation of the arc to have a special weight to it? That would be quite a departure from the other drawing tools, I don't think there is any other drawing tool that currently provides a special weight towards having it in one certain orientation or position...

One thing that I want to explore in the future is to have a "symmetry" draw helper, where you could activate one line as being the line of symmetry and then with that mode turned on various draw tools could change their behavior, and probably one of the changes could be that the arc 3 point tool would actually get completed by just drawing 2 points and having the 3rd be placed automatically around the symmetry axis.

But I'm not so sure about doing that kind of implicit directional symmetry just by default...

- Michael

Hi Michael

I guess yes i am meaning a snap point that takes into account the y axis. So I can understand how that might make more confusion than it helps. It could come under the symmetry draw helper, sounds like a good way to group changes of tool behavior. I am interested in how that develops.

Another example of how to do this is the bend tool used in spaceclaim. Basically you draw a line the use the bend tool to drag it into an arc. You can also put numerical values in. This allows me to define the start end points and then drag out an arc to fit without the end points moving. This is quite cool because you can make a box for example then drag out some arcs to give it form without the corner points moving. Also this works on 3d solids in spaceclaim.










kind regards

Jamie

Hi Jamie,
Doesnt the Arc 3 point tool do this for you? I was fooling around with it a bit. If I know the angle, I can pick my start and end points then type the angle and it seems to do this? Please bare with me as i am following this along for my own benefit.

Hi Burr

The tool does as you say, what i would like is for the start end point to be remembered so when it is edited the arc stays in place, see the picture. Hopefully it is clear. Good to have your feedback it is making it clearer what behavior i would like to see in arc tool. Maybe I'm going long way around to find out.All I know is I dont like to have to go and find the tool each time to redraw an arc when there is one there already which could just be adapted either by dragging directly or by numerical control.




kind regards

Jamie

OIC what your saying. Less about drawing it, and more about editing not working with a radius value. Draws the arc, arc shows a radius, but once edited it turns into a curve (Or endpoints grow.)