Experiences from Implementing a Mobile Multiplayer Real-Time Game for Wireless Networks with High Latency

Listing 1

Procedure for predicting movement

(1) Last received position update from player A: (𝑥₀,𝑦₀)

(2) Receive position update for player A: (𝑥₁,𝑦₁)

(3) Movement 𝑋=𝑥₁−𝑥₀

(4) Movement 𝑌=𝑦₁−𝑦₀

(5) If Movement 𝑋!=0

(6)  Movement 𝑋 = Movement 𝑋/Math.abs (Movement 𝑋) //Operate with 0’s or 1’s

(7) If Movement 𝑌!=0

(8)  Movement 𝑌 = Movement 𝑌/Math.abs (Movement 𝑌)

(9) Each time the play area is redrawn

(10)     A’s position = A’s position + (A’s speed) [Movement 𝑋, Movement 𝑌]