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diff --git a/libs/cairo-1.16.0/doc/public/html/bindings-memory.html b/libs/cairo-1.16.0/doc/public/html/bindings-memory.html deleted file mode 100644 index 961ee82..0000000 --- a/libs/cairo-1.16.0/doc/public/html/bindings-memory.html +++ /dev/null @@ -1,122 +0,0 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> -<html> -<head> -<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> -<title>Memory management: 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="language-bindings.html" title="Appendix A. Creating a language binding for cairo"> -<link rel="next" href="bindings-return-values.html" title="Multiple return values"> -<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="language-bindings.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td> -<td><a accesskey="n" href="bindings-return-values.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-memory"></a>Memory management</h2></div></div></div> -<p> - The objects in cairo can roughly be divided into two types: - reference-counted, opaque types like - <a class="link" href="cairo-cairo-surface-t.html#cairo-surface-t" title="cairo_surface_t"><span class="type">cairo_surface_t</span></a> - and plain structures like - <a class="link" href="cairo-text.html#cairo-glyph-t" title="cairo_glyph_t"><span class="type">cairo_glyph_t</span></a>. - <a class="link" href="cairo-Paths.html#cairo-path-t" title="cairo_path_t"><span class="type">cairo_path_t</span></a> - and - <a class="link" href="cairo-Paths.html#cairo-path-data-t" title="union cairo_path_data_t"><span class="type">cairo_path_data_t</span></a> - are special cases and are treated separately in this appendix. - </p> -<p> - Refcounted opaque types all have a - <code class="function">..._reference()</code> - function to increase the refcount by one and a - <code class="function">..._destroy()</code> to decrease the refcount - by one. These should not be exposed to the user of the language - binding, but rather used to implement memory management within - the language binding. The simplest way to do memory management - for a language binding is to treat the language binding object - as a simple handle to the cairo object. The language binding - object references the cairo object, and unreferences it when - finalized. This is the recommended method, though there are - a couple of caveats to be noted: - </p> -<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> -<li class="listitem"><p> - Equality won't work as expected. You can have two language - objects for the same cairo and they won't necessarily - compare equal. If the language allows customizing the - equality operation, then this is fixable by comparing - the underlying pointers. It also can be fixed by creating - at most one language object per cairo object, and - uniquifying via a <em class="firstterm">pin table</em> (a hash - table that goes from cairo object to language object). - For <span class="type">cairo_surface_t</span> you can use also - <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> - instead of a separate pin table. - </p></li> -<li class="listitem"> -<p> - Derivation from the language object doesn't work because - you can lose the language object while keeping the Cairo - object. Code like: - </p> -<pre class="programlisting"> -public class MySurface (ImageSurface) { - public MySurface (width, height) { - super (Format.ARGB32, width, height); - } - public int get42 () { - return 42; - } -} - - cr = Cairo(MySurface(width, height)); - surface = cr.getTarget(); -</pre> -<p> - Can result in <code class="varname">surface</code> containing an - <code class="classname">ImageSurface</code> not a <code class="classname">MySurface</code>. - This is not easily fixable without creating memory leaks, - and it's probably best to simply forbid deriving from the - language objects. - </p> -</li> -</ul></div> -<p> - When a plain structure is used as a return value from cairo, - this is done by passing it as a “out parameter”. - </p> -<pre class="programlisting"> -cairo_font_extents_t extents; - -cairo_font_extents (cr, &extents);</pre> -<p> - In a language binding, this should typically be treated - as a return value: - </p> -<pre class="programlisting"> -FontExtents extents = cr.fontExtents ();</pre> -<p> - A language binding has a choice in how it implements the - language objects for plain structures. It can use a pure - language object with fields corresponding to those of the C - structure, and convert from and to the C structure when calling - cairo functions or converting cairo return values. Or it - can keep a pointer to the C structure internally and wrap - it inside a language object much like occurs for refcounted - objects. The choice should be invisible to the user: they should - be able to imagine that it is implemented as a pure language - object. - </p> -</div> -<div class="footer"> -<hr>Generated by GTK-Doc V1.27</div> -</body> -</html>
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