Hi,<br><br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
    DualBox db(grid_point(0,0), grid_point(2,2));<br>
    world_point wpi(1.0,1.0);<br>
    world_point wpo(3.0,3.0);<br>
    grid_point gpi(1,1);<br>
    grid_point gpo(3,3);<br>
<br>
    bool wptrue  = boost::geometry::within(wpi,db);<br>
    bool wpfalse = boost::geometry::within(wpo,db);<br>
    bool gptrue = boost::geometry::within(gpi,db);<br>
    bool gpfalse = boost::geometry::within(gpo,db);<br></blockquote><div><br>Since within() can take 2 different geometries with potentially different point types, I&#39;m not sure to understand what can&#39;t be done in the code above using a mere grid point box. I.e. a grid point box can be passed as first argument of within() while passing a world point as 2nd argument. But maybe this particular code doesn&#39;t tell the full story of what you&#39;re trying to achieve?<br>
<br>Regarding the possible difference of scale between a grid point and a world point (your comment in the code), this is a different issue that probably appeals for something like a transformed view...<br><br>Regards<br>
Bruno<br></div></div>