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This tutorial teach you how to initialize the Direct3D Device! This is where all
your Direct3D stuff starts!

The Device
Everything in Direct3D centers around the Device. The device is an objects which communicates with the Graphics Card and tells it to render (draw) your objects.
The first step to creating any Direct3D application is Initializing the Device - you have to get it ready for some drawing!
 
Create a new project called Direct3D Initialization.

Reference:
Microsoft.DirectX
Microsoft.DirectX.Direct3D
Microsoft.DirectX.Direct3DX


(You reference the DLL's by going to the Solution Explorer (all the way to the right), and right clicking References and Add Reference. Control click the references to select multiple ones)

Now create a new class called GameClass. This class will be the center of your application

At the very top of the code, type these 3 lines:
Imports Microsoft.DirectX
Imports Microsoft.DirectX.Direct3D
Imports Microsoft.DirectX.Direct3D.D3DX


Why are we importing? So that we can declare the variables easily! Here's an example. Soon, we're going to say Dim D3DDev as Device. If we didn't import DirectX and Direct3D, we'd have to say Dim D3DDev as Microsoft.DirectX.Direct3D.Device. This just helps us save some time while coding ;p.

We're going to declare 3 more variables: the Device, the PresentationParameters, and the Displaymode.

The Device will be the object that 'talks' to our graphics card, it is the main control of our direct3D application.
The PresentationParameters are basically how we're going to present our program to the user (you'll see what I mean when we code)
The Displaymode is... well, our display mode!

__________________________

Declare the following variables.


Private D3Ddev As Device = Nothing
'Short for PresentationParameters
Private D3Dpp As PresentParameters = Nothing
Private DP As DisplayMode = Nothing


Now we're going to create a function to initialize our device, this gets the device ready for some action!

Create a new sub:

Public Sub Initialize(ByVal TargetForm As Form, ByVal FullScreen As Boolean)

End Sub


The first argument takes in the form that we're going to draw to. The 2nd argument tells us whether we're going to do this in fullscreen or windowed.

Now add the following code to the sub.

If FullScreen Then
  '800x600 Resolution
  DP.Width = 800
  DP.Height = 600
  'R5G6B5 = 16-bit. Visit MSDN to find out what the other ones are.
  DP.Format = Format.R5G6B5
Else
  'If it's not fullscreen, use the current display mode!
  DP = Manager.Adapters.Default.CurrentDisplayMode
End If


I'm sure you guys understand most of that :).
The only tricky part is the Format.R5G6B5.
Format.X8R8G8B8 is 32-bit mode. Format.R5G6B6 is 16-bit mode.

Visit this site for help on what each Format does.

The next thing to do is set up your PresentationParameters.

'As usual, we must always instantiate our classes
D3Dpp = New PresentParameters()
'Initialize some stuff for the Presentation parameters
D3Dpp.BackBufferFormat = DP.Format
D3Dpp.BackBufferWidth = DP.Width
D3Dpp.BackBufferHeight = DP.Height


What's the backbuffer you ask? The backbuffer is what Direct3D draws to. D3D draws to the backbuffer, and then takes the content of the backbuffer and draws it to the screen.

We need to set up more flags for the Presentation Parameters.

'There's flip, copy, and discard. Flip and Discard are used most often. Visit MSDN has more information.
D3Dpp.SwapEffect = SwapEffect.Discard
'Present the scene immediately
D3Dpp.PresentationInterval = PresentInterval.Immediate


Ok - let me explain. Swapeffect is a flag which basically tells Direct3D how to go from one frame to another.

SwapEffect.Discard - This flag deletes the old frame and draws a new one on top of it. Great preformance.
SwapEffect.Flip - Not sure what this does, but it provides the greatest compatibility compatibility for FullScreen and Windowed
Swapeffect.Copy - The new frame is simply copied on top of the old one. This is the most simple of the backbuffer swap operations, but it is the one with the worst performance.

"In particular, the Flip swap effect operates the same whether windowed or full-screen, and the Direct3D runtime guarantees this by creating extra buffers. As a result, it is recommended that applications use Discard whenever possible to avoid any performance penalties, because the current swap effect is always the most efficient in terms of memory consumption and performance."
"An application can use the Discard swap effect to avoid overheads and to enable the display driver to choose the most efficient presentation technique for the swap chain."

- From the DirectX Help file.

Thus, I'd recommend you use Discard, typically for FullScreen apps, although flip is common as well. Please consult MSDN for more help as I am not 100% sure on what each does.

Now to explain PresentationLevel.Immediate. Basically it means present the scene immediately when its drawn. It doesn't have to wait for other stuff to happen before presenting - just present immediately. Gets the most FPS out of your game ;).

The next few lines are simple.

'Set to Fullscreen or Windowed
If FullScreen Then
  D3Dpp.Windowed = False
Else
  D3Dpp.Windowed = True
End If


Ah cmon, no need to explain here.

The next line will be a bit tricky though.


'Instantiate the device
D3Ddev = New Device(Manager.Adapters.Default.Adapter, DeviceType.Hardware, TargetForm.Handle, CreateFlags.SoftwareVertexProcessing, D3Dpp)


Here's an explanation of the arguments

Manager.Adapters.Default.Adapter - Use the current display driver: the one that's displaying your desktop right now
DeviceType.Hardware - If you've worked with GDI+, you'll know how slow software devices are
TargetForm.Handle - Draw to the form
CreateFlags.SoftwareVertexProcessing - Processing vertices with Software (Direct3D) is safer than processing it with your hardware. This is because different graphics cards may process them differently. You want it to be processed the same universally, so you let Direct3D do the work.
D3Dpp - Well, use the presentation parameters!
We're done with this sub!
__________________

Now its time to do some rendering.

Here's what a basic rendering loop would look like:


Do While Not GameOver
  Clear
  BeginScene
  RenderTheObjects 
  EndScene
  Present
End While

We're going to do just that. In your GameClass globals,

Public GameOver As Boolean

Create a new sub:

PublicSub RenderScene()

End Sub



Add the following code to it:

Do While Not GameOver


  'Try commenting this out . You'll see what it does. It might hang your app depending on your graphics card. In DX 9.0a, the screen would flash in multiple colors if you didn't clear, this, you want to clear it with one color (see explanation below)
  D3Ddev.Clear(ClearFlags.Target, Color.FromArgb(0, 0, 225), 0, 0)
  D3Ddev.BeginScene()
    ' Rendering code goes here usually. But we're not rendering anything in this program. So don't type anything here.
  D3Ddev.EndScene()
  D3Ddev.Present()

  'In a loop, keyboard events are ignored. This means: let them NOT be ignored :).
  Application.DoEvents()

Loop

___________

Wow. That was kind of simple right? I just have to explain the D3DDev.Clear.

ClearFlags.Target - Clear the form, our "target"
Color.FromArgb(0, 0, 225) - Clear it with this color (Dark blue)
0 - ZDepth. Our app isn't 3D yet, so don't waste memory on ZDepth (Z = 3D)
0 - Stencil. Has to do with the advanced topic of Stenciling. We're not going to do that, so just set it to 0.

Now we're going to create a Terminate sub.

Public Sub Terminate()
  'Free up mem
  DP = Nothing
  D3Dpp = Nothing
  D3Ddev.Dispose()
  D3Ddev = Nothing
  'Exit
  Application.Exit()
 
'FORCE an exit if it didn't exit already.
  System.Environment.Exit(System.Environment.ExitCode)
End Sub

At the very end of RenderScene, type in
Terminate(). This insures that when GameOver = True, the application will terminate.

Wow - we're done with GameClass! It has 3 basic parts: Initialize, Render and Terminate, simple right? Now it's time to put this program into some action.
_________

Go back to form1.
Type in
Dim Game As GameClass

In the form1_load event, type in:

'We have to say Me.Show becuase the form doesn't actually get shown until AFTER the load event.
'Try emptying this sub, and type in MessageBox.Show("Hi"). Notice how
'the MessageBox appears *before* the form shows up?

Me.Show()

'As usual, we must always instantiate our classes
Game = New GameClass()

'Initialize the game
'Me - Render to form1
'True - Use fullscreen

Game.Initialize(Me, True)
Game.RenderScene()

Now go to form1_keydown.
Type this in.


If e.KeyCode = Keys.Escape Then
  Game.GameOver = True
End If


Now, it's time to run your app! Before doing so, save all of your work, just in case it crashes. You should get a blue screen :o.

That's it for this tutorial. The source code is compatible with VS. NET 2002. 2003 users will find it easy to open it and hit 'ok' when it asks to convert :)
(I hope that the files don't get corrupted from now on, because I'm uploading attachments for this section)

The source code for this tutorial can be found here.
You can also locate this by logging in to vbProgramming Forums and going to:
Tutorials > Tutorial Source Code > Source Code