It's may be no necessity to keep lines, polygons, and hatches in different tools.
A general 2D drawing tool with good settings, hatch and border options could manage all of this. (I remember Vector works was made this way.)
The question could be extended to circles and splines. Even if circle is something specific in geometry ; making circles with this general tool could give the possibility of filling a circle, writing it's area, etc.
I also realy need many times 2D drawings being visible on as many storey as I want, with something similar as slab visibility settings. (Text visibility on several storeys is also needed)
Yes, sure, it's already possible to draw many polylines with or without fill/hatch, with or without outline, using Fill tool. But not all : It's not possible to draw an open polyline or a segment this way.
The existence of Line, Polygon and Fill tools that can do sometimes the same shapes is a bit confusing. And moreover, after desining a line, you cannot convert it to polyline. Even you cannot convert a polyline to fill.
Also it's not possible to ad a fill to Splines or Circles. Now you need to use the option of automatic follow to create Fill for them. But then, this Fill is independant and can not be edited with the options of the origninal shape. If you create automaticly a Fill in a Circle, it looses centre. If you create automaticly a Fill in a Spline, it doesn't follow exactly the border. If you want to move a point of this Pseudo-Spline Fill, it doesn't react as a Spline does.
According to me, Line, polygon, circle and spline should not be specific tools but mode of creating that could apply to all 2D and 3D tools. (Why not building spline shapes walls or slabs that remain editable with spline options ?)
At least, I suppose that Line tool could be cancelled : Everything that a Line does is already possible with Polyline.
The second point is about visibility in many storeys. I will may be write an other wish for this one.
I believe I understand your wish, but a couple of the things you said are wrong.
First, you can convert lines to polylines. Edit-Reshape-Unify.
Second, you can convert a polyline to fill using the magic wand. It's not conversion by itself, but creation of a fill in the shape of the polyline. Bonus here, fill pet pallette shows some features that are extremelly useful and not found in polyline.
Fills in a spline, or walls following a spline is introducing another whole dimension, NURBS. Someone correct me if I'm wrong. This is the job of other software, such as Rhino. ArchiCAD is BIM, not a modeller. It shows many modelling options, but definitely is not a modelling software.
Moreover, some features of the 2D tools, such as "tan-tan-point", are only used in circles. Maybe a combined 2D tool for polylines and circles can be done, but I cannot find a reason AC team should do so.
Last, lines, at this moment, are useful. When creating symbol fills, you have to draw it with lines at first place. Maybe this should change, though.
For the last part, yes, create another wish, my friend.
I can work with the headline, but I think (poly)lines, splines & circles are distinctly different in their creation.
I frequently use the hatch tool for closed shapes with a transparent background to create a boundary that allows me to quickly display the hatch if required. Elsewhere in the forum there is a wish to provide display control of each vector forming the edge. If this was a possibility then I think merging hatching and lines would become a possibility. Obviously you would also need to consider the display of "arrows" at the nodes.
Splines have the same problem as arcs in 3D modelling e.g. they become facetted (like Sketchup), for AC to hatch a spline it requires a conversion to arcs, so merging in that situation is currently unlikely.
Again Circles & particularly ellipses bring their own geometric challenges for hatching, but could they be adequately approximated? It should be possible but that's one for GS.
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