paint property blending: multiply

[simonhuwiler]

Motivation

Adobe Photoshop and Illustrator allow to set the blending to multiply. Actually a really nice feature for showing data heatmap like visualizations. But in contrast to heatmaps, you dont lose the shape of your original data.
Imagine: You paint hundrets of lines on to the map. Now you set in the paint property line-blending to multiplyand you get a wonderful visualization, more accurate than heatmaps, but still the density.

I would love this feature in Mapbox GL and in the Mapbox studio editor!

Sincerely
Simon

[georgbachmann]

I'd also love to see that feature :) Is there any update on it? Will it come in the not-so-distant future? Or are devices still not performant enough?
Cheers,
Georg

[gmchocolate]

Blending mode is one of the wonderful visualization styles, I use it a lot in QGIS

[AbelVM]

Any news on this?

Composite layers were removed 6 years ago because of low performance, and this PR was closed without merging.

That happened while working on v0.1.0... It's 6 years later and the version is now v1.11... Will we have comp-op blending modes any time soon?

[cedricdelpoux]

I could be very powerful to achieve Strava like heatmap. See #10097

[floriankorn]

Any updates on this issue?
Someone has an idea of a workaround to define CSS for a geojson layer, as everything gets rendered within the mapbox canvas...?

Would really need this feature!

[bothness]

Hi all. I wanted to share a hack that I managed to come up with to achieve a multiply blend between layers.

In short, you can run two synchronised Mapbox map instances on top of one another, and use the CSS property mix-blend-mode: multiply on the <canvas> element of the top map.

The library mapbox-gl-sync-move allows you to sync the movement of the two maps.

I have put together a code pen example here (screenshot below).