Season parameters

Each biome layer carries the same eight seasonal parameters. They are written into MPC_Seasons from Blueprint or Sequencer and sampled by the biome material at runtime. Background on the system is in the season system concept.

Per-biome seasonal overrides

Parameter	Effect
Season Color	Color tint applied on top of the base albedo.
Season Offset	Tonal offset, shifts shadows.
Season Gain	Tonal gain, shifts highlights.
Season Brightness	Overall brightness shift.
Season Contrast	Contrast adjustment.
Season Saturation	Color saturation.
Season Specular	Specular intensity override.
Season Roughness	Surface roughness override.

Every biome (Tundra, Boreal Forest, Desert, Mediterranean, Savanna, Temperate Forest, Tropical Rainforest, Wetland, Grassland, Custom1, Custom2, Custom3) exposes this set. The corresponding MPC_Seasons parameter names follow the pattern BiomeXColor, BiomeXOffset, BiomeXGain, and so on, where X is the biome name.

Note

Base layers (Beach, Cliff, Gravel, Mud, Snow) are not bound to MPC_Seasons out of the box. They use their own per-surface color correction parameters. To make a base layer follow the seasons, add the variables you need to MPC_Seasons and consume them inside the base material function.

Authoring data

APLM ships four reusable structs you can use as-is or extend with your own fields:

Struct	Holds
F_ColorGrade	Packed offset, gain, brightness, contrast, saturation.
F_SeasonCore	The eight seasonal parameters listed above.
F_SeasonMetadata	Identity and labelling fields for a season entry.
F_SeasonParameters	Full seasonal block: metadata plus core values.

The Blueprint pattern that pushes these into MPC_Seasons is in the season Blueprint workflow guide.

Where to next

• Season system concept: the design rationale
• Driving seasons from Blueprint: the four-step setup
• Weather parameters: the parallel system for wet surfaces