Ah, understood.  Thanks for the nice code explanation and references... they both really help.  <div><br></div><div>I noticed that <span class="Apple-style-span" style="font-family: arial, sans-serif; font-size: 13px; border-collapse: collapse; color: rgb(34, 34, 34); ">t_canvasenvironment remains privately defined, so it&#39;s difficult to use this struct.  To get the dollarzero, I saw this works:</span></div>
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<p class="p1">canvas_setcurrent(x_canvas);</p>
<p class="p1"><span class="s1">int</span> dzero = canvas_getdollarzero();</p></div><div><br></div><div>Cheers,</div><div>Rich</div><div><br><div class="gmail_quote"><br></div></div>