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logarithmic scale

Posted: Tue Jan 03, 2017 4:04 am
by gianm
Hi,
after a change detection analysis, I've got patterns going from a few mm to a few meters in the same scene (negative and positive values).
In order to admire a large range of quantities I use the logarithmic scale. I don't understand how CC represents the negative values in the log-scaled color ramp (CC shows this message: "Scalar field contains negative values! Log scale will only consider absolute values..".

For example 2.13 m to -2.29m (linear); 2.29E+00 m to 1.19E-07 m (log).

Thank you!

Best

Gianni

Re: logarithmic scale

Posted: Thu Jan 05, 2017 8:57 am
by daniel
Yes, CloudCompare is simply displaying a color scale based on the absolute values (so as to avoid issues with the log of negative values - which is not defined). This means that -1 and 1 will have the same color.

This 'log scale' option is a bit deprecated. We should enhance it.