Variable SEASON_VERT_DECLConst
SEASON_VERT_DECL: "\n uniform sampler2D uClimateData;\n uniform vec2 uClimateSize;\n uniform float uSeasonEnabled;\n uniform float uFreezePoint;\n uniform float uFreezeBand;\n varying float vSnow;\n varying float vIce;\n" = ...
Vertex declarations for GLSL1-style shaders (the liquid materials).
Include this after
FOG_VERT_DECL, which declares the sharedcellIndexattribute — the two snippets sample the same one.