up3

server/world/biome.go

@@ -0,0 +1,67 @@
+package world
+
+import "image/color"
+
+// Biome is a region in a world with distinct geographical features, flora, temperatures, humidity ratings,
+// and sky, water, grass and foliage colours.
+type Biome interface {
+	// Temperature returns the temperature of the biome.
+	Temperature() float64
+	// Rainfall returns the rainfall of the biome.
+	Rainfall() float64
+	// Depth returns the depth of the biome.
+	Depth() float64
+	// Scale returns the scale of the biome.
+	Scale() float64
+	// WaterColour returns the water colour of the biome.
+	WaterColour() color.RGBA
+	// Tags returns the tags for the biome.
+	Tags() []string
+	// String returns the biome name as a string.
+	String() string
+	// EncodeBiome encodes the biome into an int value that is used to identify the biome over the network.
+	EncodeBiome() int
+}
+
+// biomes holds a map of id => Biome to be used for looking up the biome by an ID. It is registered
+// to when calling RegisterBiome.
+var biomes = map[int]Biome{}
+
+var biomeByName = map[string]Biome{}
+
+// RegisterBiome registers a biome to the map so that it can be saved and loaded with the world.
+func RegisterBiome(b Biome) {
+	id := b.EncodeBiome()
+	if _, ok := biomes[id]; ok {
+		panic("cannot register the same biome (" + b.String() + ") twice")
+	}
+	biomes[id] = b
+	biomeByName[b.String()] = b
+}
+
+// BiomeByID looks up a biome by the ID and returns it if found.
+func BiomeByID(id int) (Biome, bool) {
+	e, ok := biomes[id]
+	return e, ok
+}
+
+// BiomeByName looks up a biome by the name and returns it if found.
+func BiomeByName(name string) (Biome, bool) {
+	e, ok := biomeByName[name]
+	return e, ok
+}
+
+// Biomes returns a slice of all registered biomes.
+func Biomes() []Biome {
+	bs := make([]Biome, 0, len(biomes))
+	for _, b := range biomes {
+		bs = append(bs, b)
+	}
+	return bs
+}
+
+// ocean returns an ocean biome.
+func ocean() Biome {
+	o, _ := BiomeByID(0)
+	return o
+}