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<HTML><HEAD><TITLE>Xlib Programming Manual: XCreateImage</TITLE></HEAD><BODY><H1 ALIGN=center>XCreateImage</H1><H2>Syntax</H2><!.IN "XCreateImage" "" "@DEF@"><CODE><PRE><A HREF="../graphics/images.html#XImage">XImage</A> *XCreateImage(<B>display</B>, <B>visual</B>, <B>depth</B>, <B>format</B>, <B>offset</B>, <B>data</B>, <B>width</B>, <B>height</B>, <B>bitmap_pad</B>, <B>bytes_per_line</B>) <A HREF="../display/opening.html#Display">Display</A> *<B>display</B>; <A HREF="../window/visual-types.html#Visual">Visual</A> *<B>visual</B>; unsigned int <B>depth</B>; int <B>format</B>; int <B>offset</B>; char *<B>data</B>; unsigned int <B>width</B>; unsigned int <B>height</B>; int <B>bitmap_pad</B>; int <B>bytes_per_line</B>;</PRE></CODE><H2>Arguments</H2><TABLE><TR><TD> <B>display</B><TD> Specifies the connection to the X server.<TR><TD> <B>visual</B><TD> Specifies the<A HREF="../window/visual-types.html#Visual">Visual</A>structure.<TR><TD> <B>depth</B><TD> Specifies the depth of the image.<TR><TD> <B>format</B><TD> Specifies the format for the image.You can pass<B>XYBitmap</B>,<B>XYPixmap</B>,or <B>ZPixmap</B>.<TR><TD> <B>offset</B><TD> Specifies the number of pixels to ignore at the beginning of the scanline.<TR><TD> <B>data</B><TD> Specifies the image data.<TR><TD> <B>width</B><TD> Specifies the width of the image, in pixels.<TR><TD> <B>height</B><TD> Specifies the height of the image, in pixels.<TR><TD> <B>bitmap_pad</B><TD> Specifies the quantum of a scanline (8, 16, or 32).In other words, the start of one scanline is separated in client memory from the start of the next scanline by an integer multiple of this many bits. <TR><TD> <B>bytes_per_line</B><TD> Specifies the number of bytes in the client image betweenthe start of one scanline and the start of the next. </TABLE><H2>Description</H2>The<B>XCreateImage()</B>function allocates the memory needed for an<A HREF="../graphics/images.html#XImage">XImage</A>structure for thespecified display but does not allocate space for the image itself.Rather, it initializes the structure byte-order, bit-order, and bitmap-unitvalues from the display and returns a pointer to the <A HREF="../graphics/images.html#XImage">XImage</A> structure.The red, green, and blue mask values are defined for Z format images onlyand are derived from the <A HREF="../window/visual-types.html#Visual">Visual</A> structure passed in.Other values also are passed in.The offset permits the rapid displaying of the image without requiring each scanline to be shifted into position.If you pass a zero value in bytes_per_line,Xlib assumes that the scanlines are contiguousin memory and calculates the value of bytes_per_line itself.<P>Note that when the image is created using<B>XCreateImage()</B>,<B><A HREF="../graphics/XGetImage.html">XGetImage()</A></B>,or<B><A HREF="XSubImage.html">XSubImage()</A></B>,the destroy procedure that the <B><A HREF="../graphics/XDestroyImage.html">XDestroyImage()</A></B>function calls frees both the image structure and the data pointed to by the image structure.<H2>See also</H2><B><A HREF="XAddPixel.html">XAddPixel()</A></B>,<B><A HREF="XDestroyImage.html">XDestroyImage()</A></B>,<B><A HREF="XGetPixel.html">XGetPixel()</A></B>,<B><A HREF="XPutPixel.html">XPutPixel()</A></B>,<B><A HREF="XSubImage.html">XSubImage()</A></B>,"<A HREF="manipulating-images.html">Manipulating Images</A>".<HR><ADDRESS><A HREF="http://tronche.com/">Christophe Tronche</A>, <A HREF="mailto:ch.tronche@computer.org">ch.tronche@computer.org</A></ADDRESS></BODY></HTML>⌨️ 快捷键说明
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