Global Geometries handling- Quadri

Hei,

Based on my knowledge, Rhino has a old difficulty with displaying geometries in far coordinates from origin. But Grasshopper also seems to have a problem too in handeling geoemtries. In the code below, i have been trying to tranfer a geometry to Quadri straight from GH and still on Quadri it shows the geometry as broken. Any Ideas how to solve it.


Grasshopper_Quadri_ testi.gh (513.9 KB)

missing

Quite simple really. Move your geometry closer to the origin.


Quadr_2021Feb17a.gh (517.8 KB)

This is absurdly far away: {2.6473e+7, 7.2046e+6, 7.911755}

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It is not a matter of just displaying, but also creating/editing actual geometries.

If the software is forced to store big numbers, it will automatically round off “details” in your coordinates, in your geometries.

See this case in wikipedia page:


In this example you only have 5 sigificant digits, and then the exponent.

Near origin you can have a 1.001 (which is 10010 x 10^-4) and you can, for example have a circle centered at x1.001 y3.005 with radius=0.2
Far from origin, say 1.001 + 10000 it becomes 10001 x 10^0 and you lost the ability to have decimals!
So that far from origin having a good circle of radius 0.2 is impossible.

Everything is calculated base-2, binary, so it is also unpredictable, not multiple of our usual base-10 .

As Joseph said:


This, for example:
Made a circle on world origin, moved its control points really far, then rotated by 30 degree pivot on origin, then moved back near origin.


It’s no longer a circle.

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Thanks for the reply!

My aim is to keep the geometries on global/real coordinates(no local coordinates). So what i understand is that it won’t be any possible to move geometries from Gh to quad on real coordinates? otherwise manually it can be done.

hello Mohamad ,

I start using grasshopper with quarti and I have the same problèm

did you find any solutions?

thanks in advance

Hi @Fouad_HAR

I would try to model the geometries close to the origin and once they are finished, move them to the original position.

Regards!

Thank you