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Comment by app4soft | Hacker News Reader

As I'm working with CAD for a long time, I would recommend to install next three FLOSS apps (keep them all side-by-side on your PC):

1. FreeCAD — main 3D CAD (CAx);

2. QCAD — main 2D CAD (CADD);

3. SolveSpace — helper 2D/3D parametric CAD & CAE for daily engineering, sketching & relax.[0,1,2,3]

[0] https://github.com/solvespace/solvespace

[1] https://github.com/Symbian9/SolveSpace-Daily-Engineering

[2] https://www.youtube.com/playlist?list=PL53gPqUkbj3JndwS2T410...

[3] https://twitter.com/app4soft/status/1181705677984735232

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> As I'm working with CAD for a long time, I would recommend to install next three FLOSS apps (keep them all side-by-side on your PC):

Do any of these easily let you build a map from only the distances between two landmarks? I've been wanting to make an accurate map of the trees in my yard. That should be pretty easy to turn into a map using basic trig, but I don't want to do it by hand.

> Do any of these easily let you build a map from only the distances between two landmarks? I've been wanting to make an accurate map of the trees in my yard.

Use QGIS[0] or OpenOrienteering Mapper[1] (simpler than QGIS) app for any GIS/cartography/mapping tasks.

JFTR, GIS apps are "CAD for cartography"; FreeCAD/QCAD/SolveSpace are "CAD for civil engineering", but could be used for some GIS tasks.

Anyway, OpenOrienteering Mapper & QGIS are CAD apps You are looking for!

[0] https://qgis.org

[1] https://www.openorienteering.org/apps/mapper/

They're not really the same thing. I haven't found GIS apps to have the _parametric_ abilities that would allow the GP to perform the sort of constraint-based modelling they desire.

Get an older Garmin Etrex with a digital compass. These models have a sight line on the housing. You use this to project waypoints along a heading. If you traverse a base line and make two projections beyond the tree you will have four waypoints. The target will be at the intersection.

Could use Geogebra.

https://www.geogebra.org/

FreeCAD has a 2D constraints-based solver (the sketch workbench) which could be used for this.

SolveSpace in same time has 2D & 3D constraints-based solver ("libslvs").

> FreeCAD has a 2D constraints-based solver (the sketch workbench)

Fun Fact: SolveSpace solver "libslvs" used by 'realthunder' for Assembly3 Workbench for FreeCAD.[0,1]

[0] https://github.com/realthunder/FreeCAD_assembly3/wiki/Build-...

[1] https://forum.freecadweb.org/viewtopic.php?p=204024#p204024

May I ask a stupid question, can you explain how rotation works in any of those? All three axes...

I was using lightwave a lot and it was obvious, depending on view it rotated the object. For CAD software it is some sort of black magic where one axis never works.

Currently playing with bricscad but I think that my disconnect with any of CAD systems comes from same root.

I think of rotation about any axis as if I inserted into the object a skewer along that axis, and rotated the skewer. For example, rotating an object laying on the desk is achieved by rotating about the Z axis, since the "skewer" is pointing up along Z axis.

This works well in OpenSCAD and I just saw that Slic3r displays a handy arrow in the 3D preview when you focus the text box that controls the rotation

> May I ask a stupid question, can you explain how rotation works in any of those? All three axes...

What type of rotation you mean? (part rotating/posing or "spinner"/"rotor" animation)

Just turning the object on zx or zy axis (for freecad or bricscad - same issue - probably some bad ux copied from autocad). Rotation, as simple as that, center axis or any selected point. Lightwave modeler with its 4 views was understandable (always rotating on xy axis for current view) but freecad (and bricscad) is making me problems understanding how this actually functions in same manner as initial orientation of set object, i just cant figure out the logic.

(Doing 3d printed speaker stand for 3d and I am workarounding this "issue" in sweat and tears ;) )

Your question still is unclear.

> Just turning the object on zx or zy axis

There are no such type of axis, because "XY", "ZX", "ZY" — are planes formed by two crossed axis combination ("XY" plane formed by crossed "X" and "Y" axis, etc.).

> Doing 3d printed speaker stand for 3d and I am workarounding this "issue" in sweat and tears

If you mean that you need just rotate solid object from horizontal to vertical (for 3D printing) — there are few ways.

Well sorry cant explain it better (i lack the terminology, just started playing with) but looks like UCS is involved... Thank you anyway will try to figure it out on my own.

Can you draw the problem? (give some schematic image of the task)

Thank you, I'll check them all out.

Can highly recommend SolveSpace.

SolveSpace is quite fantastic as a technical achievement, but it's rather limited in terms of CAD. It's great for simple designs or just messing around, though, I'm very impressed.

> but it's rather limited in terms of CAD

SolveSpace has NO "limits in terms of CAD" (as SolveSpace 3.0 actually in active development, heavy rework & list of implemented features growing each week) — the only limits it has is that for creating _too_complex_ solids & assembly it just requires to use more tricks & more powerful PC ;)

I just took a look. It's really good. But, yeah. Has limits right now. The plan is to obviously make more possible, and a whole lot is possible right now. I know I could do a ton in that software and didn't know about it. Cool!

When people say "CAD" they are talking about any number of technical things.

Say you want to insure a free form surface is a minimum radius connecting all other surfaces. Depending on the scenario, one may be able to do that in the software today, but doing it may require well above average math and geometry skills.

In "CAD", the skill requirement is much reduced, leaving the user more focused on requirements and overall design intent, not implementation details.

Just FYI, on what "CAD" often means to people.

Latest Solvespace in Git has some nifty features and QoL improvements... it's well worth compiling if you like it.

> it's well worth compiling if you like it.

Yep, I know. I use 'master' builds since SolveSpace became open-source.[0]

SolveSpace is my daily engineering tool during last 7 years ;)

[0] http://libregraphicsworld.org/blog/entry/solvespace-released...

Yeah. This is the a similar problem with alternatives to 2D AutoCAD replacements. 2D CAD application can pretty much all do the same things. However, most of the really useful productivity features such as dynamic blocks, sheet sets, constraints etc. are absent from the cheaper or free alternatives.

I'm a hobbyist, so I don't care if things like finite element analysis simulations are missing, but I do want basic things like constraints, some of which I think SolveSpace is missing.

One big "quality of life" thing that even OnShape is missing that Fusion has is the ability to dimension a line from another line, i.e. you can specify a dimension as "line_23 / 2", which allows you to do math with the other element as a variable. It's a pretty small feature, but extremely useful.

> but I do want basic things like constraints, some of which I think SolveSpace is missing

SolveSpace has a lot of constraints & this is a key feature of SolveSpace.

What "missing constraints" you talking about?

Freecad does constraints.

Thanks! I had similar issues trying to jump into freecad to design a piece of sheet metal the other weekend for a classic car project. SolveSpace looks perfect.

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