Games [XUI2D] Tank Example

[Erel]

A simple example with a tank that moves and shoots.

The interesting point in this example is the usage of RevoluteJoint to move and control the cannon.
1. Limits are set to limit the cannon movement.
2. The joint motor is enabled all the time and we just need to change the target speed to move or hold the cannon:

If UpDown Then
   revjoint.MotorSpeed = 1
Else If DownDown Then
   revjoint.MotorEnabled = True
   revjoint.MotorSpeed = -1
Else
   revjoint.MotorSpeed = 0
   Kane.Body.AngularVelocity = 0
End If

By setting the MotorSpeed to 0 the joint motor prevents the cannon from moving when forces act on the tank.

Code to fire a cannon ball:

Private Sub Fire
   Dim template As X2TileObjectTemplate = TileMap.GetObjectTemplateByName(ObjectLayer, "bullet")
   template.BodyDef.Position = Kane.Body.Position
   'set the velocity direction based on the cannon direction.
   template.BodyDef.LinearVelocity = Kane.Body.Transform.MultiplyRot(X2.CreateVec2(30, 0))
   'better simulation of fast moving objects
   template.BodyDef.Bullet = True
   TileMap.CreateObject(template)
End Sub

To prevent the bullet from hitting the "kane" object the bullet category bits is set to 2 and the kane mask bits are set to 65533 (65535 - 2). Category bits must be a power of 2.


As usual all the game objects are defined with a tiled map:

If you don't see the custom properties in the Tiled editor then you need to import the custom properties.

The example is included in the example pack.
https://www.b4x.com/android/forum/threads/xui2d-example-pack.96454/

 

[LucaMs]

A simple example with a tank that moves and shoots.

... and hits and what it hits...!

 

[sorex]

what is the meaning of this objecttypes.json file?

was it created with Tiled aswell?

I see an object editor under view but there I can only load xml files

 

[Erel]

It defines the custom properties and their default values.

You need to import it with: View - Object Types Editor -

It is only required once or after the file is updated.

 

[sorex]

for some reason it's not working here.

I need to type in the filename because it will only list xml files but then it gives the error that it doesn't contains object types.

not really a problem for now as I can see it in the json.

 

[Erel]

It is important to see the custom types.

Are you sure that you are doing it in the right place? It can be confusing.

 

[sorex]

I guess it's the right window. And the filename is correct otherwise it gives another error.

 

[Erel]

Are you using Tiled v1.1.6?

 

[sorex]

the help>about gives 0.17.0

wait a minute copyright date is 2016 altho I downloaded and installed the latest.

let me verify something

 

[sorex]

sorry about that.

it appeared that I was still running the old one as it installed the new one in a different folder.