Simulate 'User Coordinate System' using 'rotate' and 'move'.

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Re: Simulate 'User Coordinate System' using 'rotate' and 'move'.

Post by CAD4All » Sun Sep 05, 2021 5:55 am

This is a really interesting discussion but it has overlooked a couple of points. The thread caught my eye because I had run across the problem being discussed myself and had been looking for a solution. The question has been raised of why, from a practical point of view, one would want to change the plane of the X-Y axes. In Australia, and I expect that it is so in many other parts of the world, land titles show the boundaries of blocks of land graphically and define the boundaries in terms of their length and their angle relative to due north. When a person want to seek planning permission to erect a building or to alter a building they need to provide a sketch plan that shows the location and dimensions of the building or buildings on their block. To draw up a sketch plan of the block one can use lines of the appropriate length drawn at the appropriate angles. However, the angles given on titles conform to a different coordinate system from the angles required by most CAD systems. The angles differ in two respects. As has already been pointed out, due north, rather than the X axis, is taken as 0 degrees. This is the reason for wanting to rotate the plane of the X and Y axes around the Z axis. However, this is only part of the problem. In the cartesian system degrees increase in an anticlockwise direction, whereas in navigation degrees in crease in the clockwise direction.

It is possible through a mathematical calculation to convert the angles shown on a land title to the angles required by a CAD system but the conversion involves more than simply adjusting the angle by 90 degrees which is what rotating the plane of the X and Y axes around the Z axis implies. It ought to be simple for switch between the two coordinate systems, but because the demand for CAD is so much greater in the manufacturing field, this need in drafting/architecture field goes unrecognised.

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Re: Simulate 'User Coordinate System' using 'rotate' and 'move'.

Post by CVH » Sun Sep 05, 2021 6:12 am

Hi, pitty ....
CVH wrote:
Tue Jul 13, 2021 6:34 am
The script would indeed fill in a gap that some are missing badly while others have a hard time to see the benefits of it.
In the long run one needs a fully implemented UCS ... :wink:

Both an UCS and a custom orientation handling are existing feature requests.


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Re: Simulate 'User Coordinate System' using 'rotate' and 'move'.

Post by seasdes » Sun Sep 05, 2021 7:39 am

The reason That I use custom UCS is when working on plans for buildings where the walls are not aligned along the software's X & Y axis. In many cases there are more than one building on a site and each has its own alignment (eg townhouse development). Temporarily aligning the X & Y axis to match that of the building being worked on certainly makes life easier. Easier is good.
QCAD Pro V3.26.4
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