WorldMap coloring makes countries invisible

[mwullink]

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• [*] I have checked the caravel logs for python stacktraces and included it here as text if any
• [*] I have reproduced the issue with at least the latest released version of caravel
• [*] I have checked the issue tracker for the same issue and I haven't found one similar

Caravel version

0.11.0

Expected results

World map with all the countries visible

Actual results

When 1 country has a high count value it gets a very dark color, the countries with a low count value are rendered white and they not visible anymore.

Steps to reproduce

Create set of countries with 1 country having a high count and the others with very low count. only the country with the high count and the countries without counts are visible.

[Igosuki]

Most likely there is a gradient multiplied by the value, if value is zero then it is white instead of light.
The calculation should use a base color as a threshold.

Update

const colorScale = d3.scale.linear()
    .domain([ext[0], ext[1]])
    .range(['#FFF', 'black']);

This is the code that creates the scale, which means that every zero value will be white on white background.
Most likely the person who tested this had non-zero values for every country, I think we should be able to override the default colorScale function and colors in the world map form, usage of another scale is depicted here https://bl.ocks.org/mbostock/3306362

[olbapito]

This is still the behavior. Is there any workaround to alter the color scale?
Thanks!

[ghost]

I now have the issue of countries with a 0 being darker than countries with a 1. Using 0.25.0.

[vladnvo]

The same issue

[huntg]

Still seeing this issue

[ghost]

This issue was moved by kristw to apache-superset/superset-ui-plugins#53.