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diff --git a/html/en/drv/dbuf.html b/html/en/drv/dbuf.html new file mode 100644 index 0000000..37b5c89 --- /dev/null +++ b/html/en/drv/dbuf.html @@ -0,0 +1,71 @@ +<!doctype HTML PUBLIC "-//IETF//DTD HTML//EN"> +<html> + +<head> +<meta http-equiv="Content-Language" content="en-us"> +<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> +<title>CD_DBUFFER</title> +<link rel="stylesheet" type="text/css" href="../../style.css"> +</head> + +<body> + +<h2>CD_DBUFFER - Double Buffer Driver using a server image (cddbuf.h)</h2> + + <p>Implements the concept of offscreen drawing. It is based on a Server Image + (the back buffer) and a Window canvas (the front buffer).</p> + +<h3>Use</h3> + + <p>The canvas is created by means of a call to function + <a href="../func/init.html#cdCreateCanvas"> + <font face="Courier"><strong>cdCreateCanvas</strong></font></a><font face="Courier">(CD_DBUFFER, + Data)</font>, after which other functions in the CD library can be called as + usual. This function creates a CD canvas to use with an existing window canvas + (Native Windows or IUP). The parameter <font face="Courier">Data</font> is a + pointer to the already created canvas.</p> + <p>Any amount of such canvases may exist simultaneously. It is important to + note that a call to function + <a href="../func/init.html#cdKillCanvas"> + <font face="Courier"><strong>cdKillCanvas</strong></font></a> is required to + properly <b>end</b> the driver. Call function + <a href="../func/init.html#cdKillCanvas"> + <font face="Courier"><strong>cdKillCanvas</strong></font></a> for this driver + before calling <font face="Courier"><strong>cdKillCanvas</strong></font> for + the window driver.</p> + <p>The drawing functions will work normally as if they were drawn on + the server image driver. When function <font face="Courier"><b> + <a href="../func/control.html#cdFlush"> + cdCanvasFlush</a></b></font> is executed, the image is drawn in the window canvas + passed as parameter in the canvas creation.</p> + <p>When the window's size changes, the server image is automatically recreated + using the same size as the canvas. This is done in the function + <font face="Courier"><b> + <a href="../func/init.html#cdActivate"> + cdCanvasActivate</a></b></font>.</p> +<p>We suggest you to implement rubber bands using XOR directly on the front +buffer.</p> +<p>To use this driver in Windows using GDI+ is necessary to call +<font face="Courier"><strong> + cdUseContextPlus</strong></font><strong><font face="Courier">(1)</font></strong> +before creating the canvas.</p> + +<h3>Behavior of Functions</h3> + + <p>This driver is greatly platform-dependent. For further detail, see the <b> + Behavior of Functions</b> in each platform: <a href="win32.html">Microsoft + Windows (GDI)</a>, <a href="gdiplus.html">Windows Using GDI+</a>, + <a href="xwin.html">X-Windows (XLIB)</a>. However, it should be noted that + some functions behave differently from the basic functions of each platform.</p> +<h4>Control</h4> +<ul> + <li><a href="../func/control.html#cdFlush"><font face="Courier"><strong>Flush</strong></font></a>: + draws the contents of the image into the window. It is affected by <strong> + Origin</strong> and <strong>Clipping</strong>, but not by <strong>WriteMode</strong>.</li> +</ul> +<p> </p> + + +</body> + +</html> |