[FIXED] Large coordinates does not display properly

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daniel
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Re: Large coordinates does not display properly [RESOLVED]

Post by daniel »

In fact the issue is always present whatever the shift is. It's just more or less visible: it all depends on the relative accuracy you expect. Due to the 32 bits floating point representation we use internally, you can expect issues if your relative accuracy is below 10^-6 or 10^-7 (i.e. the difference between the max coordinate amplitude and the 'details' size). For instance if you have coordinates around 1 meter, you can't expect a good accuracy if you look at details or if you expect to compute distances below a few microns). And the graphic card generally don't like it either by the way.

This is why we added the 'global shift' mechanism that is automatically suggested at loading time. But in the current version (2.5.2) the limit above which CC will suggest to apply a shift is 10^5 (100.000). And in your case the max coordinate is 99.930 so CC won't complain! And as your object is much smaller than the coordinates (around 10^-6) this strange behavior arises.

I think we'll have to be smarter in the future (either we should let the user specify the limit himself via a global parameter, otherwise we could work with 64 bits floating point values - but this will double memory consumption and users working with hundreds of millions of points will complain ;).
Daniel, CloudCompare admin
Enyan
Posts: 2
Joined: Wed Jan 08, 2014 11:18 am

Re: Large coordinates does not display properly [RESOLVED]

Post by Enyan »

Maybe a setting that forces the global shift dialog irrelevant of the limit.
In the mean time, I can just manually add one point with a value above the limit so it will ask me for the global shift.

Thanks!
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