Construction line improvement

Construction lines are very useful. If you are working on a drawing where all lines are parallel to axes, you can create an axis parallel line by referencing an existing line, but what if the lines in your drawing are not parallel to axes? then you either have to zoom out until you can see an axis line and use that as a reference, or you have to move the axis centre to where you are working. What I would like to see is a simple modifier key that enables you to choose a construction line parallel to the X, Y, or Z axis wherever you are in the drawing. I have not found a way to do this within SU nor in any app. You do it in Autocad by using the H or V key (horizontal/vertical).

Guides are drawn with the ‘Tape Measure’ tool. After the first click you’ll see the guide being drawn parallel to an axis by its color indication, either red or green or blue. Whereever you are with no axes in sight. Better than using V and H.

Also read about constraining directions to axes by using the [Arrow] keys. So what you ark is already available.

I hoped someone would respond as you have done but I guess I must be being stupid. Are you sure it is available in all versions of SU? I run it on OSX.

If I click the tape measure tool in blank space it tries to measure a distance but draws nothing. If I do the same thing from a point, it draws a line from that point to where I end it and terminates it with a reference point. If I use an edge, I get a line parallel to that edge. Using the arrow keys has no effect other than being a help in measuring distances from an offset point.

Unless I am using the wrong keys, the only way I have found of reliably getting construction lines parallel to the axes is if I can see, and so use, the axes as initial guides.

Are you clicking the start point, then pressing the left, right, or up key on your keyboard? The line SHOULD change color and be constrained to moving ONLY along the associated axis.

Oops, you are right that in empty space the tool only measures. As you can imagine, I don’t use guides that often. They tend hinder me more than they help me.
The ‘Line’ tool does what I mentioned, it draws parallel to axes by color indication (if needed, constrain to axes with the [Arrow] keys). Then take the edge to get the guide.

I can recommend the plugin that converts (replaces) edges to construction lines the lengths of the initial edges. These short dashed lines don’t disturb that much, looking at your model.

Right click an edge > Convert to Construction Line

You can force the direction inference (arrow keys) for a finite construction line BEFORE you click the starting point. The problem with these finite construction lines is that their inferencing seems to be broken (bug?).

Woah… totally misread this, too… you need SOMETHING to pull a construction line off of…

Yes Aaron, you do need something to pull the construction line off from. That’s the problem if you have no axis-parallel lines in view and no axes in view. As mentioned in these comments, there are a number of workarounds but none is as simple as a modifier key as used in AC. I’m quite surprised no app exists for it since it doesn’t seem to be a native feature. Maybe I should learn to program and produce one myself!

Another way this could be done is to have a key that temporarily shows axes in view while you hold it down so that you can pull a construction line off from it before releasing the key.

Maybe the function “Clines on Axes at Point” from TIGs Construction Lines on Axes at Point & Normal can help you? (from there you can draw more parallel clines as usual)


Even I had forgotten about that…
BUT it still works…

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Cotty and TIG, you’ve nailed it for me. Does it slightly differently from what I had in mind but no worries, this will do nicely!