Sorry I dont understand. I want just the edges to be lighted,..
void setup()
{
size(640, 360, P3D);
stroke(255);
strokeWeight(2);
noFill();
}
void draw()
{
background(0);
translate(width / 2, height / 2);
// Orange point light on the right
pointLight(150, 100, 0, // Color
200, 50, 200); // Position
rotateY(map(mouseX, 0, width, 0, PI));
rotateX(map(mouseY, 0, height, 0, PI));
box(150);
}