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diff --git a/libs/cairo-1.16.0/doc/public/html/bindings-path.html b/libs/cairo-1.16.0/doc/public/html/bindings-path.html new file mode 100644 index 0000000..717271b --- /dev/null +++ b/libs/cairo-1.16.0/doc/public/html/bindings-path.html @@ -0,0 +1,116 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> +<title>cairo_path_t: 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-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-fonts.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td> +<td><img src="right-insensitive.png" width="16" height="16" border="0"></td> +</tr></table> +<div class="sect1"> +<div class="titlepage"><div><div><h2 class="title" style="clear: both"> +<a name="bindings-path"></a>cairo_path_t</h2></div></div></div> +<p> + The <a class="link" href="cairo-Paths.html#cairo-path-t" title="cairo_path_t"><span class="type">cairo_path_t</span></a> type is one + area in which most language bindings will differ significantly + from the C API. The C API for <span class="type">cairo_path_t</span> is + designed for efficiency and to avoid auxiliary objects that + would be have to be manually memory managed by the + application. However, + a language binding should not present <span class="type">cairo_path_t</span> as an + array, but rather as an opaque that can be iterated + over. Different languages have quite different conventions for + how iterators work, so it is impossible to give an exact + specification for how this API should work, but the type names + and methods should be similar to the language's mapping of the following: + </p> +<pre class="programlisting"> +typedef struct cairo_path_iterator cairo_path_iterator_t; +typedef struct cairo_path_element cairo_path_element_t; + +cairo_path_iterator_t * +cairo_path_get_iterator (cairo_path_t *path); + +cairo_bool_t +cairo_path_iterator_has_next (cairo_path_iterator_t *iterator); + +cairo_path_element_t * +cairo_path_iterator_next (cairo_path_iterator_t *iterator); + +cairo_path_element_type_t +cairo_path_element_get_type (cairo_path_element_t *element); + +void +cairo_path_element_get_point (cairo_path_element_t *element, + int index, + double *x, + double *y); + </pre> +<p> + The above is written using the Java conventions for + iterators. To illustrate how the API for PathIterator might + depend on the native iteration conventions of the API, examine + three versions of the loop, first written in a hypothetical Java + binding: + </p> +<pre class="programlisting"> +PathIterator iter = cr.copyPath().iterator(); +while (cr.hasNext()) { + PathElement element = iter.next(); + if (element.getType() == PathElementType.MOVE_TO) { + Point p = element.getPoint(0); + doMoveTo (p.x, p.y); + } +}</pre> +<p> + And then in a hypothetical C++ binding: + </p> +<pre class="programlisting"> +Path path = cr.copyPath(); +for (PathIterator iter = path.begin(); iter != path.end(); iter++) { + PathElement element = *iter; + if (element.getType() == PathElementType.MOVE_TO) { + Point p = element.getPoint(0); + doMoveTo (p.x, p.y); + } +}</pre> +<p> + And then finally in a Python binding: + </p> +<pre class="programlisting"> +for element in cr.copy_path(): + if element.getType == cairo.PATH_ELEMENT_MOVE_TO: + (x, y) = element.getPoint(0) + doMoveTo (x, y);</pre> +<p> + While many of the API elements stay the same in the three + examples, the exact iteration mechanism is quite different, to + match how users of the language would expect to iterate over + a container. + </p> +<p> + You should not present an API for mutating or for creating new + <span class="type">cairo_path_t</span> objects. In the future, these + guidelines may be extended to present an API for creating a + <span class="type">cairo_path_t</span> from scratch for use with + <a class="link" href="cairo-Paths.html#cairo-append-path" title="cairo_append_path ()"><code class="function">cairo_append_path()</code></a> + but the current expectation is that <code class="function">cairo_append_path()</code> will + mostly be used with paths from + <a class="link" href="cairo-Paths.html#cairo-append-path" title="cairo_append_path ()"><code class="function">cairo_copy_path()</code></a>. + </p> +</div> +<div class="footer"> +<hr>Generated by GTK-Doc V1.27</div> +</body> +</html>
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