how do I apply partial transparency to my colormap?

[hrodmn]

I am experimenting with custom colormaps (via titiler-pgstac) and I am having trouble when I try to use the alpha value to control transparency.

Here is the colormap that I want. It should be 50% transparent brown and blue:

{
    0: (216, 179, 101, 127),
    1: (90, 180, 172, 127)
}

When I set alpha to anything greater than 1, I get fully opaque colors like this:

When I set alpha to anything less than 1, the color comes back 100% transparent like this:

colormap input:

{
    0: (216, 179, 101, 0.1),
    1: (90, 180, 172, 127)
}

Is there something wrong with the alpha interpretation or is this the expected behavior?

[vincentsarago]

🤔 is this using titiler or rio-tiler?

I thought we fixed this in titiler developmentseed/titiler#689

[hrodmn]

Ah ha, thank you @vincentsarago! I guess I don't fully understand the dependency structure between titiler / rio-tiler. I am pinned to titiler-pgstac==0.5.1 still, which I think is pinned to titiler>=0.12,<0.13 so now I have one more reason to upgrade to a more modern version.