// draws a "wide line segment": a rectangle of the given width and color
// whose mid-line connects two given endpoints
public static void DrawXZWideLine(Vector3 startPoint, Vector3 endPoint, Color color, float width)
{
Vector3 offset = endPoint - startPoint;
offset.Normalize();
Vector3 perp = localSpace.LocalRotateForwardToSide(offset);
Vector3 radius = perp * width / 2;
Vector3 a = startPoint + radius;
Vector3 b = endPoint + radius;
Vector3 c = endPoint - radius;
Vector3 d = startPoint - radius;
iDrawQuadrangle(a, b, c, d, color);
}
