From Spring

Sky Reflection Modifier Texture

Sets the weight for mixing the diffuse texture colour with the reflected colour of the sky. This occurs before any other shading calculations use the diffuse colour.

This can be used to suggest a surface composed of reflective materials, such as ice or crystals.

Skyreflectmod without example.png Skyreflectmod with example.png
Without Sky Reflection Modifier Map With Sky Reflection Modifier Map



The relevant sections of the mapinfo.lua

local mapinfo = {
   resources = {
      skyReflectModTex = "skyreflectmod.png",

Image File

File Location ./maps/
File Format PNG, TGA
Colour Depth 8bpp
Channels RGB
Resolution Any, recommended powers of two, will be stretched over the terrain. Should be the same size as the Mapdev:specular image
Modifies the diffuse colours as follows:
diffuseColor.r = diffuseColor.r * (1 - skyReflectModTex.r) +
                   reflectionColor.r * skyReflectModTex.r
diffuseColor.g = diffuseColor.g * (1 - skyReflectModTex.g) +
                   reflectionColor.g * skyReflectModTex.g
diffuseColor.b = diffuseColor.b * (1 - skyReflectModTex.b) +
                   reflectionColor.b * skyReflectModTex.b

Equivalent to the GLSL code: (diffuseColor is a vector)
diffuseColor = mix(diffuseColor, reflectionColor, skyReflectModTex)