Influence Maps

Planet colour information is stored in the vertices of the planet's mesh. Using Squad's terrain shader, this colour is used to determine how a surface texture appears on the terrain. For example, a brown planet will make a sand texture appear brown as well. But what if we wanted some grass poking out of the sand? Using Squad's shader, the grass will also be coloured brown, or it will appear very muddy and discoloured.

In come influence maps. Using a texture, you are able to tell the shader how much the planet colour influences the texture colour. A value of 0 means that the planet colour is shown. A value of 1 means that the texture colour is shown. A value of 0.5 means that the colour is halfway between the planet vertex colour and the texture colour.

• It is worth noting that "planetColour" is equal to "vertexColour" * "textureLuminosity".

In the image above, you can see that the grass colour is the same, regardless of what the terrain colour is. This is because the influence map is telling the shader to use more of the texture's colour.

Appearance

Influence maps are identical to displacement maps, except without an alpha channel. The steep texture is not affected by terrain colour.