TechDraw: ActiveView - units mismatch in crop width and crop height

Is there an existing issue for this?

• I have searched the existing issues

Problem description

Forum thread: https://forum.freecad.org/viewtopic.php?p=765757#p765757

When using the TechDraw_ActiveView command to insert a snapshot (bitmap) of the current 3D view, the image size is hardcoded to 1280 x 1024 px.

1. The default crop width and crop height in the dialog are the default image's x, y resolution (1280 x 1024 px) divided by 10 (128.00 x 102.40 mm). Units are then mm, without any conversion. This seems to be the first error.
2. The (cropped) Width, Height properties have no units when viewed through the property editor:

@WandererFan's comment from that thread:

In the UI, the image size fields are QuantitySpinBoxes. Not sure why this change was done, but the corresponding Properties were not changed from PropertyFloat to PropertyLength, so now we have a mis-match between the UI and the Properties - one with units, and one without. This will have to be sorted out.

[...] I need to study the options in the extended ui. There is something wonky in the centering of the image (I think).

Full version info

OS: Ubuntu Core 22 (ubuntu:GNOME/ubuntu)
Word size of FreeCAD: 64-bit
Version: 1.1.0dev.38898 (Git) Snap 1157
Build type: Release
Branch: main
Hash: 32e09d9554db26414697ed19e0189ccab4ea9029
Python 3.10.12, Qt 5.15.10, Coin 4.0.0, Vtk 7.1.1, OCC 7.7.1
Stylesheet/Theme/QtStyle: OpenLight.qss/OpenLight/Qt default
Installed mods: 
  * OpenTheme 2024.9.1
  * ezydxf
  * Ondsel-Lens 2024.9.13.02
  * Assembly4 0.50.15

Subproject(s) affected?

TechDraw

Anything else?

No response

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