NemoX 3d Tutorial 9

----TUTORIAL 9---

Loading 3D studio Models

You will Need The NemoX engine Get it Here

download the Visual Basic Source code here

Summary

1. InitEngine modification

2. Game Loop Modification

3. Collision Detection Code

1. InitEngine modification

In this tutorial we will use New Classes cNemo_3DSmesh for managing 3DS files, cNemo_Camera our new camera Class ,cNemo_Input for handle input devices (Mouse,keyBoard,joypad....not forceFeedBack for now)

For objects declaration we use vb classic class declaration for 3 Objects:

'here is the class for our 3d studio objects
Dim Mesh_3DS1 As cNemo_3DSmesh
Dim Mesh_3DS2 As cNemo_3DSmesh
Dim Mesh_3DS3 As cNemo_3DSmesh

InitEngine()

'we will used that sub for the engine initialization

'we will used that sub for the engine initialization

Sub InitEngine()

 'first thing allocate memory for the main Object
  
  Set Nemo = New NemoX
  
  Set Tool = New cNemo_Tools
 
  
   'allocate memory for our meshbuilder
    Set Mesh = New cNemo_Mesh
    
    '====New code======
    '
    '.......MEMORY ALLOCATION....
    Set KAMERA = New cNemo_Camera
    Set KEY = New cNemo_Input
    Set Mesh_3DS1 = New cNemo_3DSmesh
    Set Mesh_3DS2 = New cNemo_3DSmesh
    Set Mesh_3DS3 = New cNemo_3DSmesh
    
    
    

'we use this method
'now we allow the user to choose options
'32/16 bit backbuffer
  
  If Not (Nemo.INIT_ShowDeviceDLG(Form1.hWnd)) Then
   End 'terminate here if error
  End If
  
  'Nemo.Initialize Me.hWnd
  
  'set the back clearcolor
  Nemo.BackBuffer_ClearCOLOR = RGB(125, 125, 125) 'Gray
  
  
  
  'set some parameters
  Nemo.Set_ViewFrustum 10, 16500, 3.14 / 4, 1.01
  Nemo.Set_light True
  
  'set our camera
  KAMERA.Set_YRotation 45
  KAMERA.Set_EYE Tool.Vector(480, 50, -450)

End Sub

2. Game Loop Modification

'this sub is the main loop for a game or 3d apllication
SuSub gameLoop()

            'loop untill player press 'ESCAPE'
      'Nemo.Set_CullMode D3DCULL_NONE
      Nemo.Set_EngineRenderState D3DRS_ZENABLE, 1
    Do
       
               
               Call GetKey '=====Keyboard handler sub
               DoEvents
               
               CheckCollision  'Call Our Collision detection sub
               
               'start the 3d renderer
               Nemo.Begin3D
                     '===============ADD game rendering mrthod here
               
               'draw our ground here
              
               Mesh.Render

		'This part of code will render the 3DS meshes

		'Note that NemoX engine use built-in View Frustum Test

		'To render object only if it's visible


               'render 3ds mesh
               Mesh_3DS1.Render
               Mesh_3DS2.Render
               Mesh_3DS3.Render
               
             
               'show the FPS at pixel(5,10) color White
               Nemo.Draw_Text "FPS:" + Str(Nemo.Framesperseconde), 5, 10, &HFFFF0000
               
               Nemo.End3D
               'end the 3d renderer
            
            'check the player keyPressed
    Loop Until KEY.Get_KeyBoardKeyPressed(NEMO_KEY_ESCAPE)
            
            
    Call EndGame

En End Sub

So so start the game you add this in the form_Load code as below:

Private Sub Form_Load()
Me.Show
Me.Refresh

'call the initializer sub
Call InitEngine
    'make geometry
Call BuilGeometry

'call the main game Loop
   Call gameLoop

End Sub

To Terminate the Game we Use this:

Sub EndGame()
 'end of the demo
           Set KEY = Nothing
           Set KAMERA = Nothing
           Set Mesh_3DS = Nothing
           Set Mesh = Nothing
           
            Nemo.Free  'free resources used by the engine
           Set Nemo = Nothing
            End
End Sub

3. Collision Detection Code

In this code we're checking if a collision occurs between the player camera postion and Our world and 3DS meshes

Sub CheckCollision()

         Dim Dest As D3DVECTOR
        If Mesh.CheckCollisionSliding(Nemo.Camera_GetPosition, Dest, 20) Then

            Nemo.Camera_set_EYE Dest
       End If

End Sub

'New Code for handle collision with 3DS

'if any collision with our 3d studio mesh we slide along

     If Mesh_3DS1.Get_ColisionSliding(KAMERA.Get_Position, Dest, 20) Then
              KAMERA.Set_EYE Dest
    
     End If
 
 
     'if any collision with our 3d studio mesh we slide along

     If Mesh_3DS2.Get_ColisionSliding(KAMERA.Get_Position, Dest, 20) Then
              KAMERA.Set_EYE Dest
    
     End If
 
 
     'if any collision with our 3d studio mesh we slide along

     If Mesh_3DS3.Get_ColisionSliding(KAMERA.Get_Position, Dest, 20) Then
              KAMERA.Set_EYE Dest
    
     End If

We use this function:CheckCollisionSliding

PointVec : the point coordonates to test

RetPos: A Point (D3DVECTOR) to receive the collision response

Radius: The radius of the Sphere to be collided with Mesh Polygons

Here is a screenshot for our tutorial project

download the Visual Basic Source code here

See you in the next Tutorial.....sincerly Polaris..Don't forget Any Bugs detected mailMe

The Next: Tutorial 10 :Loading MilkShape3D models

The Previous: Tutorial 8 :Polygons Collision Detection with Response

Tutorial Written on April, 11 th 2003