On Thu, 16 May 2019 19:46:54 +0200, Mike Wey wrote:

Value.get should support all the possible types, if it doesn't that
would be a bug.

TreeModelIF.gatValue returns a Value, gobjects version of
std.variant. You can then retrieve the value using the get template
function.

For RGBA:

Value val = model.getValue(iter, MY_COLUMN);
RGBA bg = val.get!RGBA();

Ah! Okay, I think I get it, now. Thanks, Mike.