/// <summary>
/// Prepare VBO content and upload it to the GPU.
/// </summary>
private void PrepareDataBuffers()
{
if (useVBO &&
cn.result != null &&
cn.result.Vertices > 0)
{
GL.EnableClientState(ArrayCap.VertexArray);
if (cn.result.Normals > 0 && checkNormals.Checked)
{
GL.EnableClientState(ArrayCap.NormalArray);
}
if (cn.result.Colors > 0 && checkColors.Checked)
{
GL.EnableClientState(ArrayCap.ColorArray);
}
// Vertex array: [color] [normal] coord
GL.BindBuffer(BufferTarget.ArrayBuffer, VBOid[0]);
int vertexBufferSize = cn.VertexBufferSize(checkNormals.Checked, checkColors.Checked, false);
GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)vertexBufferSize, IntPtr.Zero, BufferUsageHint.DynamicDraw);
IntPtr videoMemoryPtr = GL.MapBuffer(BufferTarget.ArrayBuffer, BufferAccess.WriteOnly);
unsafe
{
stride = cn.FillVertexBuffer((float *)videoMemoryPtr.ToPointer(), checkNormals.Checked, checkColors.Checked, false);
}
GL.UnmapBuffer(BufferTarget.ArrayBuffer);
GL.BindBuffer(BufferTarget.ArrayBuffer, 0);
}
else
{
GL.DisableClientState(ArrayCap.VertexArray);
GL.DisableClientState(ArrayCap.NormalArray);
GL.DisableClientState(ArrayCap.ColorArray);
if (useVBO)
{
GL.BindBuffer(BufferTarget.ArrayBuffer, VBOid[0]);
GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)0, IntPtr.Zero, BufferUsageHint.StaticDraw);
GL.BindBuffer(BufferTarget.ArrayBuffer, 0);
}
}
}