Top Down Shooter - Move relative to player direction

There's a couple of top down shooter resources existing already. I wanted to draw together a lot of this into one neat resource.

Step One:

Make a new project (I started with the chinatown FPS from Torque 1.2) (I created my own scripts to add all the following code, but i'm just editing existing scripts in this resource to keep is simple.)

Step Two:

Create an overhead camera. Open scripts/server/gameCore.cs and inside GameCore::preparePlayer, Just after %game.loadOut(%client.player); add the following:

%client.setControlObject(%client.camera);
	%client.setCameraObject(%client.camera);  

	// Set a schedule so we can control the player
	%client.lockControlSchedule = %client.schedule(100, setControlObject, %client.player);     

	%client.setFirstPerson(false);  
	
	// This will set the orbit camera looking down at an isometic view at about 45 degrees (0.8rads)
	%client.camera.setOrbitObject(%client.player, "0.8 0 0.8", 3, 10, 0, false, "0 0 0", true);

This will allow us to control the player from a neat orbit cam view.

Step Three:

Lets stop the player from looking up and down and keep them level on the horizontal plane.

Inside scripts/client/default.bind.cs comment out the following line

moveMap.bind( mouse, yaxis, pitch );

becomes

//moveMap.bind( mouse, yaxis, pitch );

All works great, but moving the player around is a little disorientating, lets fix that and give it a twin stick shooter style controls.

Step Four:

Add the following code to the end of scripts/server/player.cs

function serverCmdUpdateMovement(%client) {  
	%euler = %client.player.getEulerRotation();
	%rot = GetWord(%euler, 2);
	

	// Messy but it works !
	if($upPressed) {
		if(%rot > 0) {
			if(%rot < 90) {
				%per = (%rot * (100/90)) / 100;
				$mvForwardAction = 1 - %per;
				$mvLeftAction = %per;
			} else {
				%rot = %rot - 90;
				%per = (%rot * (100/90)) / 100;
				$mvLeftAction = 1 - %per;
				$mvBackwardAction = %per;
			}
		} else {
			if(%rot > -90) {
				%rot = %rot * -1;			
				%per = (%rot * (100/90)) / 100;
				$mvForwardAction = 1 - %per;
				$mvRightAction = %per;
			} else {
				%rot = (%rot * -1) - 90;
				%per = (%rot * (100/90)) / 100;
				$mvRightAction = 1 - %per;
				$mvBackwardAction = %per;
			}
		}
	} else if($downPressed) {
		if(%rot > 0) {
			if(%rot < 90) {
				%per = (%rot * (100/90)) / 100;
				$mvBackwardAction = 1 - %per;
				$mvRightAction = %per;
			} else {
				%rot = %rot - 90;
				%per = (%rot * (100/90)) / 100;
				$mvRightAction = 1 - %per;
				$mvForwardAction = %per;
			}
		} else {
			if(%rot > -90) {
				%rot = %rot * -1;			
				%per = (%rot * (100/90)) / 100;
				$mvBackwardAction = 1 - %per;
				$mvLeftAction = %per;
			} else {
				%rot = (%rot * -1) - 90;
				%per = (%rot * (100/90)) / 100;
				$mvLeftAction = 1 - %per;
				$mvForwardAction = %per;
			}
		}
	} else if($leftPressed) {
		if(%rot > 0) {
			if(%rot < 90) {
				%per = (%rot * (100/90)) / 100;
				$mvBackwardAction = %per;
				$mvLeftAction = 1 - %per;
			} else {
				%rot = %rot - 90;
				%per = (%rot * (100/90)) / 100;
				$mvRightAction = %per;
				$mvBackwardAction = 1 - %per;
			}
		} else {
			if(%rot > -90) {
				%rot = %rot * -1;			
				%per = (%rot * (100/90)) / 100;
				$mvForwardAction = %per;
				$mvLeftAction = 1 - %per;
			} else {
				%rot = (%rot * -1) - 90;
				%per = (%rot * (100/90)) / 100;
				$mvRightAction = %per;
				$mvForwardAction = 1 - %per;
			}
		}
	} else if($rightPressed) {
		if(%rot > 0) {
			if(%rot < 90) {
				%per = (%rot * (100/90)) / 100;
				$mvForwardAction = %per;
				$mvRightAction = 1 - %per;
			} else {
				%rot = %rot - 90;
				%per = (%rot * (100/90)) / 100;
				$mvLeftAction = %per;
				$mvForwardAction = 1 - %per;
			}
		} else {
			if(%rot > -90) {
				%rot = %rot * -1;			
				%per = (%rot * (100/90)) / 100;
				$mvBackwardAction = %per;
				$mvRightAction = 1 - %per;
			} else {
				%rot = (%rot * -1) - 90;
				%per = (%rot * (100/90)) / 100;
				$mvLeftAction = %per;
				$mvBackwardAction = 1 - %per;
			}
		}
	} else {
		$mvForwardAction = 0; 
		$mvRightAction = 0; 
		$mvLeftAction = 0; 
		$mvBackwardAction = 0;	
	}
}

This gives us some neat controls so left is always left regardless of which way the player is facing. Lets put them into action.

Back in scripts/client/default.bind.cs replace the moveleft, moveright, moveforward and movebackward functions with the following:

$leftPressed = 0;  
$rightPressed = 0;  
$upPressed = 0;  
$downPressed = 0;  

function moveleft(%val) {  
   $leftPressed = %val;
   commandToServer('UpdateMovement');
}    
function moveright(%val) {  
   $rightPressed = %val;
   commandToServer('UpdateMovement');
}  
function moveforward(%val) {  
   $upPressed = %val;
   commandToServer('UpdateMovement');
}  
function movebackward(%val) {  
   $downPressed = %val;
   commandToServer('UpdateMovement');
}

This binds the serverCmdUpdateMovement function we wrote earlier to the movement keys.

Thus far we have a fairly functional twin stick shooter style camera and controls. Whats missing at the moment is that it only supports 4 directions. I.E. pressing up and left will only move up.

If you move the mouse with a movement key still down the player will move in that direction. If this is something you don't want you can stop this by amending the "yaw" function in default.bind.cs to:

function yaw(%val)
{

		
	
   %yawAdj = getMouseAdjustAmount(%val);
   if(ServerConnection.isControlObjectRotDampedCamera())
   {
      // Clamp and scale
      %yawAdj = mClamp(%yawAdj, -m2Pi()+0.01, m2Pi()-0.01);
      %yawAdj *= 0.5;
   }

   $mvYaw += %yawAdj;
   
   // sets movement relative to player direction.
   commandToServer('UpdateMovement');  
   
}

Hope this helps some people.