Bezier Curve issue

pvpeng

Hi all, 4 points are defined as follows:

float[,] ctrlpoints = new float [4,3] {{ -4.0f, -4.0f, 0.0f }, { -2.0f, 4.0f, 0.0f }, { 2.0f, -4.0f, 0.0f }, { 4.0f, 4.0f, 0.0f }};

When the 4 points are called in following method:

private void openGLControl_OpenGLDraw(object sender, RenderEventArgs e)
{
// Get the OpenGL object.
OpenGL gl = openGLControl.OpenGL;

//  Clear the color and depth buffer.
gl.Clear(OpenGL.GL\_COLOR\_BUFFER\_BIT | OpenGL.GL\_DEPTH\_BUFFER\_BIT);

int i;

gl.Color(1.0f, 1.0f, 1.0f);
gl.Begin(OpenGL.GL\_LINE\_STRIP);
for (i = 0; i <= 30; i++)
{
    gl.EvalCoord1((float)i / 30.0);
}
gl.End();
// display the control points
gl.PointSize(5.0f);
gl.Color(1.0f, 1.0f, 0.0f);
gl.Begin(OpenGL.GL\_POINTS);
for (i = 0; i < 4; i++)
{
    gl.Vertex(&ctrlpoints\[i\]\[0\]);
}
gl.End();
gl.Flush();

}

The &ctrlpoints[i][0] in gl.Vertex(&ctrlpoints[i][0]) was displayed to be an error. How to fix the problem? Thanks!

Richard Deeming

Which language are you using? Most of your syntax looks like C#, but &ctrlpoints[i][0] looks like C++ (or possibly C# in an unsafe context). If it's C#, what's the signature of the Vertex method in the Object Browser?

"These people looked deep within my soul and assigned me a number based on the order in which I joined." - Homer

Lost User

pvpeng wrote:

was displayed to be an error.

What error; please do not expect people to guess what messages you are seeing. I cannot find a description for either a Vertex function, or class constructor; is this something you have created yourself?

Bernhard Hiller

Didn't you understand the answer to your previous question http://www.codeproject.com/Messages/4850994/How-to-write-an-element-address-of-array-in-Csharp.aspx[^]? You must use the unsafe keyword and use its respective compiler option.