   Player Movement to jumpy
  I am currently moving my player this wayif(playerRight)playerDir +=PLAYERDIR_ACCEL_CONSTANT;if(playerLeft)playerDir -=PLAYERDIR_ACCEL_CONSTANT;I would like to be able to move the players left/right movements faster but keep a fine control also... I tried doing thisif(playerRight)playerDir +=PLAYERDIR_ACCEL_CONSTANT * velocity;if(playerLeft)playerDir -=PLAYERDIR_ACCEL_CONSTANT * velocity;But that makes the player start to jump a bit to much when moving side to side at higher speeds and doesn't allow the player to move side to side unless they are moving fwd... So any ideas on how to overcome this? What about some kind of normalization of the playerDir? BTW playerDir is a scalar...Thanks   
  You could clamp velocity before scaling your rotation change.dir += input * Clamp(speed, 0.5f, 1.0f) * dirChangeRate;This would make it so only after speed was at .5 or above would the "steering" get more responsive. You could also lerp:dir += input * Lerp(speed/maxSpeed, minDirChangeRate, maxDirChangeRate);You could also apply some kind of bump value for when the input sign changes, so if you go from right to left, or left to right, it temporarily turns really fast.You could also do it based on the input derivitive.inputVelocity = (lastInput - currentInput) / dt; //clamp inputVelocity to something usable.dir += input * dirChangeRate * inputVelocity;Any variant of a PID will be usable.   ;  Personally I use a normalized vector H which I rotate around the y axis to indicate the player heading.Then I compute the velocity as:V = H * move_velocity.If you want to have slide as well you can compute it as:S = (V x [0,1,0]T) * slide_velocity.Add gravity as:G = G + GRAVITATION_ACC * TIME_IN_AIR;Generalizing you could update your position as:P += (H + S + G) * time_scalar.You can add or remove forces, but the point in the next position is the sum of forces. That gives you a somewhat realistic motion.You can gradually increase the velocity scalars to create acceleration but the model is basically the same.   