如何绘制（x，y，z）

Question

无论如何以vb形式绘制x（来自x文本框），y（来自y文本框）和z（来自z文本框）？ 这是Windows应用程序。我有三个文本框，表示x，y，z坐标。我想知道是否有任何工具或方法向用户显示这一点。

Answer 1

这里有两条主要途径。 1）将（x，y，z）坐标转换为平面项目（x，y）并使用gdi+在屏幕上绘制，或2）使用opentk直接绘制点到GLControl，但您必须先设置视口和投影。

它不是很漂亮，但这是VS2010使用OpenTK的概念验证。

public partial class Form1 : Form
{
    bool loaded=false;

    public Form1()
    {
        InitializeComponent();
    }

    public Vector3 PointCoordinates
    {
        get
        {
            float x=0, y=0, z=0;
            float.TryParse(xTextBox.Text, out x);
            float.TryParse(yTextBox.Text, out y);
            float.TryParse(zTextBox.Text, out z);

            return new Vector3(x, y, z);
        }
        set
        {
            xTextBox.Text=value.X.ToString();
            yTextBox.Text=value.Y.ToString();
            zTextBox.Text=value.Z.ToString();
        }
    }
    protected override void OnLoad(EventArgs e)
    {
        base.OnLoad(e);

        PointCoordinates=new Vector3(0, 0, 0);
        loaded=true;
        SetupViewPort();
    }

    private void glControl1_Resize(object sender, EventArgs e)
    {
        if(!loaded) return;
        SetupViewPort();
    }

    private void glControl1_Paint(object sender, PaintEventArgs e)
    {
        glControl1.MakeCurrent();
        GL.ClearColor(glControl1.BackColor);
        GL.Clear(ClearBufferMask.ColorBufferBit|ClearBufferMask.DepthBufferBit);

        GL.MatrixMode(MatrixMode.Modelview);
        GL.LoadIdentity();

        SetupCamera();

        // Draw Coordinate System
        GL.LineWidth(1.5f);
        GL.Begin(PrimitiveType.Lines);
        GL.Color3(Color.Red);
        GL.Vertex3(0, 0, 0);
        GL.Vertex3(1, 0, 0);
        GL.Vertex3(0.85, 0.05, -0.05);
        GL.Vertex3(1, 0, 0);
        GL.Vertex3(0.85, -0.05, 0.05);
        GL.Vertex3(1, 0, 0);
        GL.Color3(Color.Green);
        GL.Vertex3(0, 0, 0);
        GL.Vertex3(0, 1, 0);
        GL.Vertex3(-0.05, 0.85, 0.05);
        GL.Vertex3(0, 1, 0);
        GL.Vertex3(0.05, 0.85, -0.05);
        GL.Vertex3(0, 1, 0);
        GL.Color3(Color.Blue);
        GL.Vertex3(0, 0, 0);
        GL.Vertex3(0, 0, 1);
        GL.Vertex3(-0.05, 0.05, 0.85);
        GL.Vertex3(0, 0, 1);
        GL.Vertex3(0.05, -0.05, 0.85);
        GL.Vertex3(0, 0, 1);
        GL.End();

        // Draw a single point
        var vector=PointCoordinates;
        GL.PointSize(5f);
        GL.Begin(PrimitiveType.Points);
        GL.Color3(Color.Black);
        GL.Vertex3(vector);
        GL.End();
        GL.PointSize(3f);
        GL.Begin(PrimitiveType.Points);
        GL.Color3(Color.Yellow);
        GL.Vertex3(vector);
        GL.End();

        glControl1.SwapBuffers();
    }

    void SetupViewPort()
    {
        float wt=Math.Max(1, glControl1.Width);
        float ht=Math.Max(1, glControl1.Height);
        float sz=(float)Math.Sqrt(ht*wt);
        GL.Viewport((int)(wt-sz)/2, (int)(ht-sz)/2, (int)sz, (int)sz);
        var ortho=Matrix4.CreateOrthographic(
            10f, 10f, 1f, 200f);
        GL.MatrixMode(MatrixMode.Projection);
        GL.LoadMatrix(ref ortho);
    }

    void SetupCamera()
    {
        Matrix4 lookAt=Matrix4.LookAt(
                        10f, 5f, 15f,
                        0f, 0f, 0f,
                        0f, 1f, 0f);
        GL.MatrixMode(MatrixMode.Modelview);
        GL.LoadMatrix(ref lookAt);
    }

    private void button1_Click(object sender, EventArgs e)
    {
        glControl1.Refresh();
    }

}