Scaling icons after stacking and/or game not generating mipmaps

[gridstop]

I'm programmatically generating some virtual signals based on the planets in the game, similar to how the game internally generates planet route icons (with the two planets and the arrows).

So I have a stackup like this:

Code: Select all

icons = {
        { icon = data.raw.planet[source].icon, icon_size = 64, scale = 0.60, shift = {-12,-12}, draw_background = false },
        { icon = data.raw.planet[dest].icon, icon_size = 64, scale = 0.60, shift = {12, 12}, draw_background = false },
        { icon = "__virtual-planet-channels__/graphics/icons/planet-channel.png", icon_size = 64, scale = 1, draw_background = true}
},

The end result looks great in the virtual signal list when choosing with a constant combinator, or when pulling up the factoriopedia. Looks very similar to the planet routes that are auto-generated. But when you select a single signal for a constant combinator and have alt display on, the icon is larger than the constant combinator. And if you select 4 signals, it overlaps the others, too. But if I try to scale it down at all, the icon in the selection menus looks wrong. I don't see a way to scale the end result of the icons array stackup.

I looked and other virtual signal icons seem to have 64x64 as their 'top' mipmap. But either my resulting stack is the wrong size, and I don't see how to change it, or the image is okay but the game is somehow not generating the smaller mipmaps for it?

Appreciate any help.