Drawing sections of a vertex array

[shadowmouse]

I'm making a graph drawing program where I'm using an sf::VertexArray to represent the graph itself. My problem comes from graphs such as y=asin(1/x). These graphs have a gap in the middle where the value of y is undefined. My problem is, how do I stop the vertex array from drawing specific vertices? Even with a circle equation, I'll have to stop it drawing the vertices before and after the circle so is there any way to do this?

[Rhimlock]

You could just add 2 additional vertices with a transparent color in the gap.

Example:

Vertices  0 |  1 |  2 | 3 | 4 | 5
X-Coord -1 |  0 |  0 | 0 | 0 | 1
Y-Coord -1 | -1 | -1 | 1 | 1 | 1

[shadowmouse]

Won't that interpolate the colour so that the lines before the gap will fade out and the line after will fade in?

EDIT: I've just realised exactly what you meant and thank you that should do what I'm trying to do. If I put the transparent vertices in exactly the same position as the opaque ones, then there will be no fade out.

[Hapax]

It's also possible to use sf::Lines rather than sf::LinesStrip although the alpha trick can simplify things nicely.