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qgis / QGIS

QGIS is a free, open source, cross platform (lin/win/mac) geographical information system (GIS)
https://qgis.org
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Heatmap renderer should feature a holding feature or a way to compute the maximum value over a layer #27898

Open qgib opened 5 years ago

qgib commented 5 years ago

Author Name: vince - (vince -) Original Redmine Issue: 20076

Redmine category:symbology

The heatmap renderer is a very handy tool, but if the MAX value is set to "automatic", that value is recomputed each time the zoom factor changes, leading to inconsistencies in the way the data is displayed (e.g. dark zones, when zoomed in, become bright) – at least when using a PostGIS layer.

Therefore, it would be worth adding a box or something allowing to calibrate the ramp w/r to the layer's maximum instead of taking into account only the displayed area. That would let the user choose between a "global" or a "local" coloring scheme.

qgib commented 5 years ago

Author Name: Giovanni Manghi (@gioman)

magerlin commented 1 year ago

Agree on this - I am creating an atlas layout and I need to go and set the max manually to get same scale on all the atlas pages.

At least a possibility to set it by you own coding could be nice so I could use a project variable for it. As for now it is only Automatic or a manually hardcoded value that is possible.