Centres of Area

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debenriver
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Centres of Area

Post by debenriver »

Hi Eric

I love the new centres of area feature :D :D But is it possible to make it so that the calculation can be turned off in preferences – with really complex polygons it slows the program down so that it actually stops responding and I have to force quit. On RC b9 the same drawing is fine (slightly slow, but fine). It only has two objects in it, both polygons, so I guess that calculation is the problem. It could be turned on when needed, but the program wouldn't have to carry the overhead all the time.

Cheers -- George

Edit: Or maybe make it available by selecting Action >> length and area? That is a largely redundant command at the moment because the same info is available in the Edit pallet – George
Eric Pousse
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Location: Tours - France

Re: Centres of Area

Post by Eric Pousse »

Bonjour George,

Can you send to me a file like this?
I want to see if I can speed up the calculation.

Thanks.
Eric Pousse
debenriver
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Re: Centres of Area

Post by debenriver »

I'll email it now!

George

Edit – I turned them back to lines to see how many elements there were – one has 2851 sides and the other has 2703 sides – so they are very "poly" polygons :D
Eric Pousse
Posts: 1064
Joined: Sat Dec 03, 2011 12:31 pm
Location: Tours - France

Re: Centres of Area

Post by Eric Pousse »

George,

In your case, the test to verify if the polygon is "simple" i.e. if no side cut another side is very time consuming.
2 solutions :
- turn off this test but in some case the result is wrong;
- calculate the center only when the user asks it via a menu for example.

Cordialement.
Eric Pousse
debenriver
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Re: Centres of Area

Post by debenriver »

Bonjour Eric

I can understand that - there are 2800+ sides!

The test that if no side cuts another is really useful because if that is the case, then you don't get a CoA – which tells me that somewhere I have something wrong – usually a double line from a trim that has joined into the polygon – so when it goes to be CNC cut, there is going to be an error. So I can search for this and correct it. Only when I get a CoA do I know that I have a simple polygon and good for CNC. It has made checking for CNC much easier for me, which was an unexpected side-benefit :D

My strong personal preference would be to retain the test and enable the calculation when you want it.

Can you do it with Action >> Length and area? That would seem the logical place. So you select a polygon and click Action >> Length and area and the CoA appears. Actually no real need to display the L, P & S data because that is already displayed in the Edit pallet. If so, maybe change the name to Area or Centre of Area.

If that's not possible, then a simple checkbox in Preferences would be just fine as far as I am concerned.

After all it's a very specific bit of data – not something you necessarily need to see all the time.

Cheers -- Georges

PS: I can't tell you how useful CoA's is for me – it does sail areas, centre of lateral area of underwater hull, all sorts of things that I hadn't even thought about originally. Made a huge difference to the speed I can do calculations. :D :D :D
Eric Pousse
Posts: 1064
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Location: Tours - France

Re: Centres of Area

Post by Eric Pousse »

Bonjour George,

A new beta is available : http://www.adx-online.com/RealCADD441b11_Mac.zip

For polygons with less than 100 sides, this version works like beta 10.
For polygons with more than 100 sides, the center is calculated only via the menu "Length, area and center".

And I have added a little "triangle" in the layer's pallet.

Cordialement.
Eric Pousse
debenriver
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Re: Centres of Area

Post by debenriver »

Good Morning Eric!

That seems a perfect solution. :D

I notice that the Area (S) of a 100+ polygon now shows as NAN in the Edit panel – I guess that's because it's not testing for area, just for length and perimeter. You get the area from the Action >> Length, areas & center menu.

One small glitch is that when you do Action >> Length, areas & centre, the Attributes pallet defaults to Line transparency 0%, thickness 0.3, Back transparency 0% for the CoA mark – so you can't see it – you have to draw a marquee where you think it might be to select it and then change the transparency to 100% – and the line thickness etc to whatever you usually use etc.

While fiddling about with this I noticed that if you use the Action >> Apply attributes it transfers the colour (of the Line & Back) but not the Transparency %.

The Layers pallet is now much better on a small screen – thank you

Cheers -- George
Eric Pousse
Posts: 1064
Joined: Sat Dec 03, 2011 12:31 pm
Location: Tours - France

Re: Centres of Area

Post by Eric Pousse »

Bonjour George and thank you !

It is fixed and I will release soon RealCADD 4.50, not 4.41 because there is many new features and enhancements.

Cordialement.
Eric Pousse
debenriver
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Joined: Sat Dec 03, 2011 9:19 pm
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Re: Centres of Area

Post by debenriver »

Hi Eric

Sounds good to me! :D

I hope that you will extend the Command Line to all the applicable tools – I now use it all the time.

Cheers -- George
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