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我试图学习如何在 VB .NET 环境中执行 openGL,似乎建议使用 Tao 框架或 OpenTK,而 OpenTK 具有更高的推荐,所以这就是我选择尝试使用的。

因为我是新手,所以我试着画一个简单的盒子、三角形或任何真正的东西,这样我就可以在制作更复杂的东西之前理解它们。到目前为止我一直没有成功,所以我将按顺序列出我到目前为止所做的事情,希望这里有人可以帮助我纠正它或提供一个新示例,以便我可以绘制一个简单的形状。

1) 我使用 opentk-2010-10-06.exe 安装了 OpenTK

2) 在一个新项目中,我添加了对 OpenTK.dll 和 OpenTK.Compatibility.dll 的引用

3)我添加了控件(opentk.glcontrol.dll)

4)我将实际控件添加到我的表单中。

使用一些在线示例,我添加了其余部分:

5)我在以下位置写了我的参考资料:

Imports OpenTK
Imports OpenTK.GLControl
Imports OpenTK.Platform
Imports OpenTK.Graphics.OpenGL
Imports System.Math

6)我的全局变量:

 Dim _STARTED As Boolean = False

7)我写了我的事件:

Private Sub GlControl1_Resize(ByVal sender As Object, ByVal e As System.EventArgs) Handles GlControl1.Resize _STARTED = True ResizeGL() End Sub

Private Sub ResizeGL()
    GL.Viewport(0, 0, GlControl1.Width, GlControl1.Height)
    GL.MatrixMode(MatrixMode.Projection) ' Select The Projection Matrix
    GL.MatrixMode(MatrixMode.Modelview) ' Select The Modelview Matrix
    GL.LoadIdentity() ' Reset The Modelview Matrix
End Sub


Public Sub ViewPerspective() ' Set Up A Perspective View

    GL.MatrixMode(MatrixMode.Projection) ' Select Projection
    GL.LoadIdentity() ';    
    Dim perspective1 As Matrix4 = OpenTK.Matrix4.CreatePerspectiveFieldOfView(MathHelper.PiOver4, _
                                         CSng((GlControl1.Width) / (GlControl1.Height)), 0.1, 1000)
    GL.LoadMatrix(perspective1)
    GL.MatrixMode(MatrixMode.Modelview) ' Select The Modelview Matrix
    GL.LoadIdentity() ' Reset The Matrix
    GL.Enable(EnableCap.DepthTest) ' This doesnt need to be here but.. If your using the Z buffer.. It dont hurt.

End Sub


Public Sub ViewOrtho()
    GL.MatrixMode(MatrixMode.Projection) 'Select Projection
    GL.LoadIdentity() ' Reset The Matrix
    GL.Ortho(0, GlControl1.Width, -GlControl1.Height, 0, 0.1, 100.0) ' Select Ortho Mode
    GL.MatrixMode(MatrixMode.Modelview) ' Select Modelview Matrix
    GL.LoadIdentity() ' Reset The Matrix
End Sub

8)最后,我试着给他们打电话:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    ViewOrtho()
End Sub

以上结果没有显示,所以任何帮助将不胜感激。

即使您不知道完整的解决方案,任何回应都会很好。

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2 回答 2

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请也发布您的渲染代码(即您的 Paint 事件处理程序)。您发布的代码设置了 OpenGL 视口和投影矩阵,但实际上并没有渲染任何东西。

于 2012-02-22T10:38:35.960 回答
0

我已经解决了我自己的问题:p 我创建了一个包装类,这样我就可以根据输入绘制一些基元,这应该允许我绘制很多东西:圆形、多边形、三角形和文本。

Private Sub GlControl1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles GlControl1.Load
    GL.ClearColor(Color.Black)
    SetupViewport()
End Sub

Public Sub SetupViewport()
    Dim w As Integer = GlControl1.Width
    Dim h As Integer = GlControl1.Height
    GL.MatrixMode(MatrixMode.Projection)
    GL.LoadIdentity()
    GL.Ortho(0, w, 0, h, -1, 1)
    GL.Viewport(0, 0, w, h)
End Sub


Private Sub GlControl1_Resize(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles GlControl1.Resize
    SetupViewport()
    GlControl1.Invalidate()
End Sub


Private Sub GlControl1_Paint(ByVal sender As System.Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles GlControl1.Paint
    GL.Clear(ClearBufferMask.ColorBufferBit)
    GL.Clear(ClearBufferMask.DepthBufferBit)

    'go through list and draw shapes
    Dim i As Integer = 0
    Try
        Do Until i = objectsettings.GetUpperBound(1) + 1
            Select Case objectsettings(1, i)
                Case "circle"
                    draw_circle(objectsettings(2, i), objectsettings(3, i), objectsettings(5, i), objectsettings(12, i))
                Case "polygon"
                    draw_polygon(objectsettings(2, i), objectsettings(3, i), objectsettings(6, i), objectsettings(7, i), objectsettings(4, i), objectsettings(12, i))
                Case "text"
                    draw_text(objectsettings(2, i), objectsettings(3, i), objectsettings(6, i), objectsettings(7, i), objectsettings(4, i), objectsettings(8, i), objectsettings(12, i))
                Case "triangle"
                    draw_triangle(objectsettings(2, i), objectsettings(3, i), objectsettings(4, i), objectsettings(9, i), objectsettings(10, i), objectsettings(11, i), objectsettings(12, i))
                Case Else
                    Exit Do
            End Select


            i = i + 1
        Loop
    Catch
    End Try



    GlControl1.SwapBuffers()

End Sub
于 2012-02-24T21:51:39.247 回答