public override void Render(Camera camera, double t)
{
vao.Begin();
normals_shader.Begin();
normals_shader.SetUniforms(camera);
GL.DrawArrays(PrimitiveType.Points, 0, length);
normals_shader.End();
points_shader.Begin();
points_shader.SetUniforms(camera);
GL.DrawArrays(PrimitiveType.Points, 0, length);
points_shader.End();
vao.End();
}