XNA 4.0 Game Development by Example Visual Basic Edition > Asteroid Belt Assault Lost in Space > Time for action - updating and drawing the player's ship

Private Sub imposeMovementLimits()
Dim location as Vector2 = playerSprite.Location
If location.X < playerAreaLimit.X Then
location.X = playerAreaLimit.X
End If
If location.X >
(playerAreaLimit.Right - playerSprite.Source.Width) Then
location.X =
(playerAreaLimit.Right - playerSprite.Source.Width)
End If
If location.Y < playerAreaLimit.Y
location.Y = playerAreaLimit.Y
End If
If location.Y >
(playerAreaLimit.Bottom - playerSprite.Source.Height) Then
location.Y =
(playerAreaLimit.Bottom - playerSprite.Source.Height)
End If
playerSprite.Location = location
End Sub

Add the Update() method to the PlayerManager class:

Public Sub Update(gameTime As GameTime)
PlayerShotManager.Update(gameTime)
If Not Destroyed Then
playerSprite.Velocity = Vector2.Zero
shotTimer += CSng(gameTime.ElapsedGameTime.TotalSeconds)
HandleKeyboardInput(Keyboard.GetState())
HandleGamepadInput(GamePad.GetState(PlayerIndex.One))
playerSprite.Velocity.Normalize()
playerSprite.Velocity *= playerSpeed
playerSprite.Update(gameTime)
imposeMovementLimits()
End If
End Sub

Add the Draw() method to the PlayerManager class:

Public Sub Draw(spriteBatch As SpriteBatch)
PlayerShotManager.Draw(spriteBatch)
If Not Destroyed Then
playerSprite.Draw(spriteBatch)
End If
End Sub

Add a declaration to the Game1 class for the PlayerManager:
```
Private _playerManager As PlayerManager
```

In the LoadContent() method of the Game1 class, set up the PlayerManager, after the AsteroidManager is initialized:

_playerManager = New PlayerManager(
spriteSheet,
New Rectangle(0, 150, 50, 50),
3,
New Rectangle(
0,
0,
Me.Window.ClientBounds.Width,
Me.Window.ClientBounds.Height))

In the Update() method of the Game1 class, add an update line for the PlayerManager, right after the AsteroidManager is updated:
```
_playerManager.Update(gameTime)
```
In the Draw() method of the Game1 class, add a draw line for the PlayerManager, right after the AsteroidManager is drawn:
```
_playerManager.Draw(spriteBatch)
```
Execute the game and fly your star fighter around in the asteroid field. Fire off a few shots with your cannon!

What just happened?

The imposeMovementLimits() method begins by making a copy of the playerSprite's Location property. Since Location is a property and not a public member, we cannot modify the components of the vector (X and Y) individually. Creating a temporary copy allows us to independently modify these values, and then save the whole vector back to the property.

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Contents

Chapter 4. Asteroid Belt Assault Lost in... > Time for action - updating and drawi...

Time for action - updating and drawing the player's ship

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