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diff --git a/documentation/drawing.html b/documentation/drawing.html index 375649af6..d8be83f6c 100644 --- a/documentation/drawing.html +++ b/documentation/drawing.html @@ -746,6 +746,25 @@ function finds and returns the width and height. The return value is non-zero if the dimensions were parsed ok and zero if there was any problem. +<H3>Direct Image Reading</H3> + +<p>FLTK provides a single function for reading from the current +window or off-screen buffer into a RGB(A) image buffer.</p> + +<H4><A NAME="fl_read_image">uchar *fl_read_image(uchar *p, int +X, int Y, int W, int H, int alpha = 0);</A></H4> + +<p>Read a RGB(A) image from the current window or off-screen +buffer. The <tt>p</tt> argument points to a buffer that can hold +the image and must be at least <tt>W*H*3</tt> bytes when reading +RGB images and <tt>W*H*4</tt> bytes when reading RGBA images. If +<tt>NULL</tt>, <tt>fl_read_image()</tt> will create an array of +the proper size which can be freed using <tt>delete[]</tt>.</p> + +<p>The <tt>alpha</tt> parameter controls whether an alpha +channel is created and the value that is placed in the alpha +channel. If 0, no alpha channel is generated.</p> + <H3><A name="Fl_Image">Image Classes</A></H3> <P>FLTK provides a base image class called <A |