Using the Device Material instead of Vertex Color

[davedwards]

Hi,

 

I'm having a little difficulty using the material of the device.

 

As an example, I've modified tutorial 2 from DirectX SDK, to use Transformed vertices instead of TransformedColored vertices, and then I set the Device Material to Red. However, when I render the triangle is not red, but white. Can anyone tell me what I am doing wrong?

 

Imports System

Imports System.Drawing

Imports System.Windows.Forms

Imports Microsoft.DirectX

Imports Microsoft.DirectX.Direct3D

 

 

Namespace VerticesTutorial

Public Class Vertices

Inherits Form

' Our global variables for this project

Private device As device = Nothing ' Our rendering device

Private vertexBuffer As vertexBuffer = Nothing

 

Public Sub New()

Me.ClientSize = New System.Drawing.Size(300, 300)

Me.Text = "Direct3D Tutorial 2 - Vertices"

End Sub 'New

 

Public Function InitializeGraphics() As Boolean

Try

Dim presentParams As New PresentParameters()

presentParams.Windowed = True

presentParams.SwapEffect = SwapEffect.Discard

device = New Device(0, DeviceType.Hardware, Me, CreateFlags.SoftwareVertexProcessing, presentParams)

AddHandler device.DeviceCreated, AddressOf Me.OnCreateDevice

Me.OnCreateDevice(device, Nothing)

Return True

Catch e As DirectXException

Return False

End Try

End Function 'InitializeGraphics

 

Public Sub OnCreateDevice(ByVal sender As Object, ByVal e As EventArgs)

Dim dev As Device = CType(sender, Device)

vertexBuffer = New VertexBuffer(GetType(CustomVertex.Transformed), 3, dev, Usage.WriteOnly, CustomVertex.Transformed.Format, Pool.Default)

AddHandler vertexBuffer.Created, AddressOf Me.OnCreateVertexBuffer

Me.OnCreateVertexBuffer(vertexBuffer, Nothing)

 

End Sub 'OnCreateDevice

 

Public Sub OnCreateVertexBuffer(ByVal sender As Object, ByVal e As EventArgs)

Dim vb As VertexBuffer = CType(sender, VertexBuffer)

Dim verts As CustomVertex.Transformed() = CType(vb.Lock(0, 0), CustomVertex.Transformed())

verts(0) = New CustomVertex.Transformed(150, 50, 0.5F, 1)

verts(1) = New CustomVertex.Transformed(250, 250, 0.5F, 1)

verts(2) = New CustomVertex.Transformed(50, 250, 0.5F, 1)

vb.Unlock()

End Sub 'OnCreateVertexBuffer

 

Private Sub Render()

'Clear the backbuffer to a blue color

device.Clear(ClearFlags.Target, System.Drawing.Color.Blue, 1.0F, 0)

'Begin the scene

device.BeginScene()

 

' Set the material

Dim mat As New Material()

mat.Ambient = Color.Red

mat.Diffuse = Color.Red

device.Material = mat

 

device.SetStreamSource(0, vertexBuffer, 0)

device.VertexFormat = CustomVertex.Transformed.Format

device.DrawPrimitives(PrimitiveType.TriangleList, 0, 1)

device.EndScene()

device.Present()

End Sub 'Render

 

Shared Sub Main()

 

Dim frm As New Vertices()

frm.InitializeGraphics()

frm.Show()

 

While frm.Created

frm.Render()

Application.DoEvents()

End While

End Sub 'Main

End Class 'Vertices

End Namespace 'VerticesTutorial

[Rakka Rage]

i think you need lights and normals for that kind of color

[davedwards]

You're right about the lights. I've since learned that all materials has to do with the how light is reflected from the surface. Materials don't do anything if Lighting is not turned. And you do need normals if you want shading.

 

In order to get the coloring that I wanted, I needed to set Lighting to true, and set both the diffuse and emmissive color to the color I wanted. I didn't even have to add a light to the scene, because the emmissive color disregards any lights in the scene. It was critical, even though there were no lights in the scene, to have Lighting turned on.

 

Thanks for your reply