up3

server/block/cube/orientation.go

@@ -0,0 +1,33 @@
+package cube
+
+import "math"
+
+// Orientation represents the rotation of a block divided into 16 options.
+type Orientation int
+
+// OrientationFromYaw returns an Orientation value that (roughly) matches the
+// yaw passed.
+func OrientationFromYaw(yaw float64) Orientation {
+	yaw = math.Mod(yaw, 360)
+	return Orientation(math.Round(yaw / 360 * 16))
+}
+
+// Yaw returns the yaw value that matches the orientation.
+func (o Orientation) Yaw() float64 {
+	return float64(o) / 16 * 360
+}
+
+// Opposite returns the opposite orientation value of the Orientation.
+func (o Orientation) Opposite() Orientation {
+	return OrientationFromYaw(o.Yaw() + 180)
+}
+
+// RotateLeft rotates the orientation left by 90 degrees and returns it.
+func (o Orientation) RotateLeft() Orientation {
+	return OrientationFromYaw(o.Yaw() - 90)
+}
+
+// RotateRight rotates the orientation right by 90 degrees and returns it.
+func (o Orientation) RotateRight() Orientation {
+	return OrientationFromYaw(o.Yaw() + 90)
+}