面试题：Visual Basic中VR虚拟现实项目搭建基础

步骤

创建新项目：打开Visual Basic开发环境，创建一个新的项目。
添加必要的引用：通常需要添加对DirectX等支持3D图形的库的引用（具体取决于使用的VR开发框架）。假设使用DirectX，在项目属性中添加对DirectX相关库的引用。
初始化DirectX设备：在代码中初始化DirectX设备，用于渲染图形。
场景建模 - 创建正方体：
- 定义顶点数据：正方体有8个顶点，每个顶点包含位置、颜色等信息。
- 定义索引数据：用于指定如何连接顶点形成三角形面。
设置正方体颜色：在顶点数据中设置每个顶点的颜色信息。
渲染场景：在渲染循环中，将正方体渲染到场景中。

关键代码示例（以DirectX为例，简化代码，假设已正确引用DirectX库）

' 定义DirectX设备等变量
Dim d3d As Direct3D9
Dim device As Direct3DDevice9

' 顶点结构定义
Private Type Vertex
    position As D3DXVECTOR3
    color As Long
End Type

' 定义正方体顶点和索引
Dim cubeVertices(0 To 7) As Vertex
Dim cubeIndices(0 To 35) As Integer

Private Sub Form_Load()
    ' 初始化DirectX
    Set d3d = New Direct3D9
    Dim presentParams As D3DPRESENT_PARAMETERS
    presentParams.Windowed = True
    presentParams.SwapEffect = D3DSWAPEFFECT_DISCARD
    presentParams.hDeviceWindow = Me.hWnd
    Set device = d3d.CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, Me.hWnd, D3DCREATE_HARDWARE_VERTEXPROCESSING, presentParams)
    
    ' 填充正方体顶点数据
    cubeVertices(0).position = D3DXVECTOR3(-1, -1, 1)
    cubeVertices(0).color = &HFF0000 ' 红色
    cubeVertices(1).position = D3DXVECTOR3(1, -1, 1)
    cubeVertices(1).color = &HFF0000
    cubeVertices(2).position = D3DXVECTOR3(1, 1, 1)
    cubeVertices(2).color = &HFF0000
    cubeVertices(3).position = D3DXVECTOR3(-1, 1, 1)
    cubeVertices(3).color = &HFF0000
    cubeVertices(4).position = D3DXVECTOR3(-1, -1, -1)
    cubeVertices(4).color = &H00FF00 ' 绿色
    cubeVertices(5).position = D3DXVECTOR3(1, -1, -1)
    cubeVertices(5).color = &H00FF00
    cubeVertices(6).position = D3DXVECTOR3(1, 1, -1)
    cubeVertices(6).color = &H00FF00
    cubeVertices(7).position = D3DXVECTOR3(-1, 1, -1)
    cubeVertices(7).color = &H00FF00
    
    ' 填充正方体索引数据
    cubeIndices(0) = 0: cubeIndices(1) = 1: cubeIndices(2) = 2
    cubeIndices(3) = 0: cubeIndices(4) = 2: cubeIndices(5) = 3
    cubeIndices(6) = 4: cubeIndices(7) = 5: cubeIndices(8) = 6
    cubeIndices(9) = 4: cubeIndices(10) = 6: cubeIndices(11) = 7
    cubeIndices(12) = 0: cubeIndices(13) = 1: cubeIndices(14) = 5
    cubeIndices(15) = 0: cubeIndices(16) = 5: cubeIndices(17) = 4
    cubeIndices(18) = 2: cubeIndices(19) = 3: cubeIndices(20) = 7
    cubeIndices(21) = 2: cubeIndices(22) = 7: cubeIndices(23) = 6
    cubeIndices(24) = 1: cubeIndices(25) = 2: cubeIndices(26) = 6
    cubeIndices(27) = 1: cubeIndices(28) = 6: cubeIndices(29) = 5
    cubeIndices(30) = 0: cubeIndices(31) = 3: cubeIndices(32) = 7
    cubeIndices(33) = 0: cubeIndices(34) = 7: cubeIndices(35) = 4
End Sub

Private Sub Form_Paint()
    device.Clear 0, ByVal 0, D3DCLEAR_TARGET, &HFF000000, 1, 0
    device.BeginScene
    ' 设置顶点格式
    device.VertexFormat = D3DFVF_XYZ Or D3DFVF_DIFFUSE
    ' 创建顶点缓冲区
    Dim vertexBuffer As Direct3DVertexBuffer9
    device.CreateVertexBuffer 8 * Len(cubeVertices(0)), D3DUSAGE_WRITEONLY, device.VertexFormat, D3DPOOL_DEFAULT, vertexBuffer, 0
    Dim pVertices As Long
    vertexBuffer.Lock 0, 0, pVertices, 0
    CopyMemory ByVal pVertices, cubeVertices(0), 8 * Len(cubeVertices(0))
    vertexBuffer.Unlock
    ' 创建索引缓冲区
    Dim indexBuffer As Direct3DIndexBuffer9
    device.CreateIndexBuffer 36 * 2, D3DUSAGE_WRITEONLY, D3DFMT_INDEX16, D3DPOOL_DEFAULT, indexBuffer, 0
    Dim pIndices As Long
    indexBuffer.Lock 0, 0, pIndices, 0
    CopyMemory ByVal pIndices, cubeIndices(0), 36 * 2
    indexBuffer.Unlock
    ' 设置顶点和索引缓冲区
    device.SetStreamSource 0, vertexBuffer, 0, Len(cubeVertices(0))
    device.Indices = indexBuffer
    ' 绘制正方体
    device.DrawIndexedPrimitive D3DPT_TRIANGLELIST, 0, 0, 8, 0, 12
    ' 释放资源
    indexBuffer.Release
    vertexBuffer.Release
    device.EndScene
    device.Present ByVal 0, ByVal 0, ByVal 0, ByVal 0
End Sub

Private Sub Form_Unload(Cancel As Integer)
    device.Release
    d3d.Release
End Sub

面试题：Visual Basic中VR虚拟现实项目搭建基础

知识考点

面试题答案

步骤

关键代码示例（以DirectX为例，简化代码，假设已正确引用DirectX库）