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diff --git a/libs/cairo-1.16.0/doc/public/html/bindings-surfaces.html b/libs/cairo-1.16.0/doc/public/html/bindings-surfaces.html new file mode 100644 index 0000000..c0b5701 --- /dev/null +++ b/libs/cairo-1.16.0/doc/public/html/bindings-surfaces.html @@ -0,0 +1,92 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> +<title>Surfaces: Cairo: A Vector Graphics Library</title> +<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> +<link rel="home" href="index.html" title="Cairo: A Vector Graphics Library"> +<link rel="up" href="language-bindings.html" title="Appendix A. Creating a language binding for cairo"> +<link rel="prev" href="bindings-patterns.html" title="Patterns"> +<link rel="next" href="bindings-fonts.html" title="Fonts"> +<meta name="generator" content="GTK-Doc V1.27 (XML mode)"> +<link rel="stylesheet" href="style.css" type="text/css"> +</head> +<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> +<table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="5"><tr valign="middle"> +<td width="100%" align="left" class="shortcuts"></td> +<td><a accesskey="h" href="index.html"><img src="home.png" width="16" height="16" border="0" alt="Home"></a></td> +<td><a accesskey="u" href="language-bindings.html"><img src="up.png" width="16" height="16" border="0" alt="Up"></a></td> +<td><a accesskey="p" href="bindings-patterns.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td> +<td><a accesskey="n" href="bindings-fonts.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td> +</tr></table> +<div class="sect1"> +<div class="titlepage"><div><div><h2 class="title" style="clear: both"> +<a name="bindings-surfaces"></a>Surfaces</h2></div></div></div> +<p> + Like patterns, surfaces, which use only the + <a class="link" href="cairo-cairo-surface-t.html#cairo-surface-t" title="cairo_surface_t"><span class="type">cairo_surface_t</span></a> + type in the C API should be broken up into a hierarchy of types + in a language binding. + </p> +<pre class="programlisting"> +cairo_surface_t + cairo_image_surface_t + cairo_atsui_surface_t + cairo_win32_surface_t + cairo_xlib_surface_t + cairo_beos_surface_t + </pre> +<p> + Unlike patterns, the constructors and methods on these types are + clearly named, and can be trivially associated with the + appropriate subtype. Many language bindings will want to avoid + binding the platform-specific subtypes at all, since the + methods on these types are not useful without passing in native + C types. Unless there is a language binding for Xlib available, + there is no way to represent a XLib <span class="type">Display</span> * in + that language. + </p> +<p> + This doesn't mean that platform-specific surface types can't + be used in a language binding that doesn't bind the constructor. + A very common situation is to use a cairo language binding in + combination with a binding for a higher level system like + the <a class="ulink" href="http://www.gtk.org/" target="_top">GTK+</a> widget + toolkit. In such a situation, the higher level toolkit provides + ways to get references to platform specific surfaces. + </p> +<p> + The <a class="link" href="cairo-cairo-surface-t.html#cairo-surface-set-user-data" title="cairo_surface_set_user_data ()"><code class="function">cairo_surface_set_user_data()</code></a>, + and <a class="link" href="cairo-cairo-surface-t.html#cairo-surface-get-user-data" title="cairo_surface_get_user_data ()"><code class="function">cairo_surface_get_user_data()</code></a> + methods are provided for use in language bindings, and should + not be directly exposed to applications. One example of the use + of these functions in a language binding is creating a binding for: + </p> +<pre class="programlisting"> +cairo_surface_t * +<a class="link" href="cairo-Image-Surfaces.html#cairo-image-surface-create-for-data" title="cairo_image_surface_create_for_data ()"><code class="function">cairo_image_surface_create_for_data</code></a> (unsigned char *data, + cairo_format_t format, + int width, + int height, + int stride); +</pre> +<p> + The memory block passed in for <em class="parameter"><code>data</code></em> must be + kept around until the surface is destroyed, so the language + binding must have some way of determining when that happens. The + way to do this is to use the <em class="parameter"><code>destroy</code></em> + argument to <code class="function">cairo_surface_set_user_data()</code>. + </p> +<p class="remark"><em><span class="remark"> + Some languages may not have a suitable “pointer to a block of + data” type to pass in for <em class="parameter"><code>data</code></em>. And even + where a language does have such a type, the user will be + frequently able to cause the backing store to be reallocated + to a different location or truncated. Should we recommend a + standard type name and binding for a buffer object here? + </span></em></p> +</div> +<div class="footer"> +<hr>Generated by GTK-Doc V1.27</div> +</body> +</html>
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