问同一个winform上的多个glControl不工作- OpenTK C#

EN

Bitmap videoFrame = null;//should show this frames in glcontrol1
Bitmap videoFrame2 = null;//should show this frames in glcontrol2
IGraphicsContext control2Context;
openTK obj_openTK = new openTK();//common class for opengl functions
private void Show_Click(object sender, EventArgs e)
{
control2Context = new GraphicsContext(GraphicsMode.Default,glControl2.WindowInfo);
GL.ClearColor(Color.MidnightBlue);
GL.Enable(EnableCap.DepthTest);
TexUtil.InitTexturing();
GL.Hint(HintTarget.PerspectiveCorrectionHint, HintMode.Nicest);
GL.DepthFunc(DepthFunction.Lequal);
GL.ColorMaterial.ColorMaterial
(MaterialFace.FrontAndBack,ColorMaterialParameter.AmbientAndDiffuse);
GL.Enable(EnableCap.ColorMaterial);
GL.Enable(EnableCap.Blend);
GL.BlendFunc(BlendingFactor.SrcAlpha, BlendingFactor.OneMinusSrcAlpha);
GL.Ext.BindFramebuffer(FramebufferTarget.FramebufferExt, 0); // render per default onto screen, not some FBO

glControl1.Resize += new EventHandler(glControl1_Resize);
glControl1.Paint += new PaintEventHandler(glControl1_Paint);
glControl2.Resize += new EventHandler(glControl2_Resize);
glControl2.Paint += new PaintEventHandler(glControl2_Paint);

Application.Idle += Application_Idle;
glControl1_Resize(glControl1, EventArgs.Empty);
glControl2_Resize(glControl2, EventArgs.Empty);
}
private void Application_Idle(object sender, EventArgs e)
{
while (glControl1.IsIdle)
{
glControl1.MakeCurrent();
Render();
GL.Flush();
glControl1.SwapBuffers();

control2Context.MakeCurrent(glControl2.WindowInfo);
Render2();
GL.Flush();
glControl2.SwapBuffers();
}
}
public void Render ()
{
GL.BindFramebuffer(FramebufferTarget.Framebuffer, 0); // use the visible framebuffer
if (videoFrame != null)
lock (videoFrame)//frames from video 1
{
    if (videoTexture != -1)
    GL.DeleteTextures(1, ref videoTexture);
    videoTexture = LoadTexture(videoFrame);
    videoFrame.Dispose();
    videoFrame = null;
 }
GC.Collect();
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
obj_openTK.DrawImage(videoTexture, glControl1);
 }
public void Render2()
{
 GL.BindFramebuffer(FramebufferTarget.Framebuffer, 0); // use the visible framebuffer
 if (videoFrame2 != null)
 lock (videoFrame2) // frames from video 2
 {
    if (videoTexture2 != -1)
    GL.DeleteTextures(1, ref videoTexture2);
    videoTexture2 = LoadTexture(videoFrame2);
    videoFrame2.Dispose();
    videoFrame2 = null;
}
GC.Collect();
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
obj_openTK.DrawImage(videoTexture2,glControl2);
}
private void glControl1_Paint(object sender, PaintEventArgs e)
{
obj_openTK .Render();
}
private void glControl1_Resize(object sender, EventArgs e)
{
obj_openTK.Init();
}
private void glControl2_Paint(object sender, PaintEventArgs e)
{
obj_openTK.Render2();
}
private void glControl2_Resize(object sender, EventArgs e)
{
obj_openTK.Init();
}
========================
class openTK
{
int positionLocation1;
int program;
int positionLocation;
int vertShader;
int fragShader;
int buffer;
float[] vertices = {
        // Left bottom triangle
        -1f, -1f, 0f,
        1f, -1f, 0f,
        1f, 1f, 0f,
        // Right top triangle
        1f, 1f, 0f,
       -1f, 1f, 0f,
       -1f, -1f, 0f
};

public int LoadTexture(Bitmap bitmap)
{
    int tex = -1;
    if (bitmap != null)
    {
        GL.Hint(HintTarget.PerspectiveCorrectionHint, HintMode.Nicest);

        GL.GenTextures(1, out tex);
        GL.BindTexture(TextureTarget.Texture2D, tex);

        bitmap.RotateFlip(RotateFlipType.RotateNoneFlipY);
        BitmapData data = bitmap.LockBits(new System.Drawing.Rectangle(0, 0, bitmap.Width, bitmap.Height),
       ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format32bppArgb);

        GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Rgba, data.Width, data.Height, 0,
        OpenTK.Graphics.OpenGL.PixelFormat.Bgra, PixelType.UnsignedByte, data.Scan0);
        bitmap.UnlockBits(data);

        GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.Linear);
        GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);
        GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int)TextureWrapMode.ClampToEdge);
        GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)TextureWrapMode.ClampToEdge);
    }
    return tex;
}
public void DrawImage(int image, GLControl glControl)
{
    GL.MatrixMode(MatrixMode.Projection);
    GL.PushMatrix();
    GL.LoadIdentity();
    GL.MatrixMode(MatrixMode.Modelview);
    GL.PushMatrix();
    GL.LoadIdentity();
    GL.Disable(EnableCap.Lighting);
    GL.Enable(EnableCap.Texture2D);
    GL.ActiveTexture(TextureUnit.Texture0);
    GL.BindTexture(TextureTarget.Texture2D, image);
    GL.Uniform1(positionLocation1, 0);

    RunShaders();

    GL.Disable(EnableCap.Texture2D);
    GL.PopMatrix();

    GL.MatrixMode(MatrixMode.Projection);
    GL.PopMatrix();

    GL.MatrixMode(MatrixMode.Modelview);

    ErrorCode ec = GL.GetError();
    if (ec != 0)
        System.Console.WriteLine(ec.ToString());
    Console.Read();            
}
  private void RunShaders()
 {
 GL.UseProgram(program);
 GL.DrawArrays(PrimitiveType.Triangles, 0, vertices.Length / 3);
 ErrorCode ec = GL.GetError();
 if (ec != 0)
 System.Console.WriteLine(ec.ToString());
 Console.Read();
 }   
 private void Init()
 {
 CreateShaders();
 CreateProgram();
 InitBuffers();
 }  
 private void CreateProgram()
 {
 program = GL.CreateProgram();
 GL.AttachShader(program, vertShader);
 GL.AttachShader(program, fragShader);
 GL.LinkProgram(program);
 }
private void InitBuffers()
{
buffer = GL.GenBuffer();
positionLocation = GL.GetAttribLocation(program, "a_position");
positionLocation1 = GL.GetUniformLocation(program, "sTexture");
GL.EnableVertexAttribArray(positionLocation);
GL.BindBuffer(BufferTarget.ArrayBuffer, buffer);
GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)(vertices.Length * sizeof(float)), vertices, BufferUsageHint.StaticDraw);
GL.VertexAttribPointer(positionLocation, 3, VertexAttribPointerType.Float, false, 0, 0);
}
private void CreateShaders()
 {
/***********Vert Shader********************/
 vertShader = GL.CreateShader(ShaderType.VertexShader);
 GL.ShaderSource(vertShader, @"attribute vec3 a_position;
                        varying vec2 vTexCoord;
                        void main() {
                        vTexCoord = (a_position.xy+1)/2 ;
                        gl_Position = vec4(a_position, 1);
                        }");
 GL.CompileShader(vertShader);

/***********Frag Shader ****************/
fragShader = GL.CreateShader(ShaderType.FragmentShader);
GL.ShaderSource(fragShader, @"precision highp float;
uniform sampler2D sTexture;varying vec2 vTexCoord; 
                 void main ()
                 {
               vec4    color   = texture2D (sTexture, vTexCoord);
               gl_FragColor    = color;                 
                 }");
 GL.CompileShader(fragShader);
   }
  }