Drawing a subset of a vertex array?

[smurf]

I have a particle system where sparks burn out over time.
Instead of creating a brand new VertexArray every frame with the burnt-out particles removed, I wanted to re-use the same VertexArray and just shift things around so that the burnt-out ones are on the end, and then not draw them by passing a count parameter to the Draw function. The idea is by not creating a new VertexArray every frame this should be much more performant.

But it seems the window.Draw function does not quite give me the overload I need.

renderWindow.Draw(vertexArray, 0, vertexCount, vertexArray.PrimitiveType);

This is invalid code because the first parameter needs to be an array of vertices instead of a vertexArray 

but the VertexArray class does not expose its internal array of vertices. So any way I can do this?

[fallahn]

You can use the [] operator of VertexArray

window.draw(&vertices[offset], count, sf::Triangles);
 

[smurf]

Thanks!

But I'm using SFML.Net and it doesn't seem to have that in C#