[Discussion] Orientation of Windows and Doors

[vocx]

It seems people struggle to understand how to correctly place Arch Windows and Doors within Arch Walls, especially if they aren't parallel to the main XZ or YZ planes, or if they need to be moved to a different wall, or rotated to a different orientation once created. Another issue that is also confusing is that in many cases the window or door doesn't trigger a recompute of the host wall when changes occur, so the wall displays incorrect holes.

I collect a few threads that discuss these topics for reference.

• Complex Preset Doors/Windows don't rotate
• Re: Arch Window - Glass Panel Area etc in Python Script?
• [Bug] Arch Wall doesn't update itself when a Window is removed from it
• [Discussion] Sketches that support Windows and Doors have a strange orientation
• Positioning Windows
• Adding windows to a rectangular wall
• Arch Window on Non-Linear Wall?
• Moving window with wall

I found the tutorials by jpg87 very informative as well

• Arch Create a custom window
• Arch : How to use your custom Window

I decided to prepare a tutorial with some explanation on how the Normal property of the Window works, and how it can be calculated to orient the window in the desired position. I'm not entirely sure if this is correct, but it's something I can use as reference for the time being.

• Tutorial custom placing of windows and doors

In this thread, Arch Window on Non-Linear Wall?, Yorik explains a bit how the Window does its internal calculations for the Normal. I didn't see it before writing the tutorial, so I didn't include that information. Has anything changed significantly since then?

obtaining a normal depends on your shape. In DraftGeomUtils module there is a getNormal() function that tries to obtain a normal from any shape you give to it. Better be it a flat shape, otherwise the result can be not what you want. But for something flat (face or wire(s)) it works well. This will get a normal for a selected object:

import DraftGeomUtils
DraftGeomUtils.getNormal(Gui.Selection.getSelection()[0].Shape)

I think from a usability point of view, the automatic calculation of the window's Normal should be improved. In the second tutorial by jpg87, and in the wiki, it is shown that even if you rotate the base sketch, or if you remap the sketch to a new plane, the Window doesn't automatically adjust the Normal.

In most cases, the user shouldn't be calculating the normal and changing the value manually. Maybe a button can be added to the Window's Task panel so the user can choose any face so that FreeCAD calculates the Normal and orients the object in the desired direction.

[yorik]

Has anything changed significantly since then?

Basically how things work now:

- you press the Window button, and hover the mouse over the wall where you wan tot insert it
- when your mouse is over a face, the tool gets the normal direction of that face, and orients the window on it
- when you click to insert the window, the last orientation is kept and determines how the base sketch must be positioned

Internally:

- If the Normal property of the window is set (not 0,0,0), it overrides all the rest and defines the normal direction (ie. the extrusion direction) of the window
- if not, the normal direction is taken by guessing the normal direction of the underlying 2D object (sketch or whatever) using DraftGeomUtils.getNormal().

[vocx]

...
- if not, the normal direction is taken by guessing the normal direction of the underlying 2D object (sketch or whatever) using DraftGeomUtils.getNormal().

What about a tool "Re-orient Normal", which does this calculation again, in case the window or the sketch is moved?

[yorik]

If the sketch is moved, and provided the Normal property of the window is (0,0,0), this calculation is done again automatically

[vocx]

If the sketch is moved, and provided the Normal property of the window is (0,0,0), this calculation is done again automatically

Yes, I know. But from a usability point of view, a new, inexperienced user won't know that he or she has to put the normal to (0,0,0). It will be a long time until the user figures out (reads somewhere in the manual) that entering (0,0,0) does the trick. An explicit button, menu, or right click menu that says "Re-orient normal" which does this would be better.

[yorik]

Hmm i see your point... Indeed that's a good idea. Maybe a right-click option? That's a good place for such things...

[Roy_043]

Thank you @vocx for pointing out this discussion, I somehow missed it. And also thank you for the tutorial.

Some remarks from my side (note: I have not read the other topics vocx linked to):

1.

when your mouse is over a face, the tool gets the normal direction of that face, and orients the window on it

I actually hadn't really noticed this behavior before. Prior to following the tutorial I would always align the WP with the correct wall face. IMO this behavior should be explained in the Arch Window section of the wiki.

2.
When creating a sketch for a window you should pay close attention to the creation order of the "loops". The numbering of the wires in the "Windows elements" dialog depends on it. Again this is something that should ideally be mention in the wiki.

3.
Regarding the Normal property of windows:
IMO it would be a good idea to use 0,0,0 as the default Normal property for all windows. In most cases the underlying 2D object is aligned with the wall and using the normal of that object to create the window makes perfect sense. Note: for the correct extrusion of the window this normal vector must be reversed however.

Related topic:
https://forum.freecadweb.org/viewtopic.php?f=23&t=39760

[vocx]

1.
I actually hadn't really noticed this behavior before. Prior to following the tutorial I would always align the WP with the correct wall face. IMO this behavior should be explained in the Arch Window section of the wiki.

I think this is not stressed in the wiki because it is "discoverable"; the user can figure this out just by trying. If you just select the window, and then move the tracker over a wall, you can see how the window aligns itself automatically.

2.
When creating a sketch for a window you should pay close attention to the creation order of the "loops". The numbering of the wires in the "Windows elements" dialog depends on it. Again this is something that should ideally be mention in the wiki.

Okay, I have added this bit.

It is evident that the Arch documentation is missing many things. I wish I had some time and motivation to bring the documentation on par with Draft Workbench's one. To document Draft, I basically had to test every single tool in the workbench and cross reference with the code, and see how everything worked, and then document that, including problems, if any.

3.
Regarding the Normal property of windows:
IMO it would be a good idea to use 0,0,0 as the default Normal property for all windows. ...

As I proposed earlier, I think it would be good to have a menu option, right click context menu, or button with a command "reset normal", or "reverse normal", to adjust the normal direction of the window. The user cannot be expected to know all this about normals, but right clicking is easier to discover. Unfortunately it hasn't been implemented. I think it wouldn't be that hard. Something like

Code: Select all

def reset_normal(self):
    self.normal = App.Vector(0, 0, 0)

def reverse_normal(self):
    self.normal = self.normal * -1