start game logic and pong physics

internal/pong/state.go

@@ -0,0 +1,25 @@
+package pong
+
+type GameState struct {
+	Score   map[string]int
+	Player1 Player
+	Player2 Player
+	Ball    Ball
+}
+
+type Vector struct {
+	X float32
+	Y float32
+}
+
+type Player struct {
+	client GameClient
+	Pos    Vector
+	Size   Vector
+	Speed  float32
+}
+
+type Ball struct {
+	Pos Vector
+	Vel Vector
+}