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diff --git a/manuals/sly/Rectangles.html b/manuals/sly/Rectangles.html new file mode 100644 index 0000000..7a1fb4f --- /dev/null +++ b/manuals/sly/Rectangles.html @@ -0,0 +1,262 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 2013, 2014 David Thompson davet@gnu.org + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 +or any later version published by the Free Software Foundation; +with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. +A copy of the license is included in the section entitled "GNU +Free Documentation License". + +A copy of the license is also available from the Free Software +Foundation Web site at http://www.gnu.org/licenses/fdl.html. + + +The document was typeset with +http://www.texinfo.org/ (GNU Texinfo). + --> +<!-- Created by GNU Texinfo 6.0, http://www.gnu.org/software/texinfo/ --> +<head> +<title>Sly: Rectangles</title> + +<meta name="description" content="Sly: Rectangles"> +<meta name="keywords" content="Sly: Rectangles"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta charset="UTF-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Index.html#Index" rel="index" title="Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Math.html#Math" rel="up" title="Math"> +<link href="Transforms.html#Transforms" rel="next" title="Transforms"> +<link href="Vectors.html#Vectors" rel="prev" title="Vectors"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.indentedblock {margin-right: 0em} +blockquote.smallindentedblock {margin-right: 0em; font-size: smaller} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smalllisp {margin-left: 3.2em} +kbd {font-style: oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space: nowrap} +span.nolinebreak {white-space: nowrap} +span.roman {font-family: serif; font-weight: normal} +span.sansserif {font-family: sans-serif; font-weight: normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en"> +<a name="Rectangles"></a> +<div class="header"> +<p> +Next: <a href="Transforms.html#Transforms" accesskey="n" rel="next">Transforms</a>, Previous: <a href="Vectors.html#Vectors" accesskey="p" rel="prev">Vectors</a>, Up: <a href="Math.html#Math" accesskey="u" rel="up">Math</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index.html#Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Rectangles-1"></a> +<h4 class="subsection">4.2.2 Rectangles</h4> + +<div class="example"> +<pre class="example">(use-modules (sly math rect)) +</pre></div> + +<p>Rects are 2D axis-aligned bounding boxes. They are useful for +defining rectangular regions, such as the hitbox of a game entity, or +the viewport of a camera. Because rects are axis-aligned, they +provide a cheap means to perform simple collision detection. +</p> +<p>The <code><rect></code> type descriptor has been exposed for use with +Guile’s <code>(ice-9 match)</code> pattern matching module. +</p> +<dl> +<dt><a name="index-_003crect_003e"></a>Scheme Variable: <strong><rect></strong></dt> +<dd><p>Rectangle data type with fields <code>x</code>, <code>y</code>, <code>width</code>, +<code>height</code>, in that order. +</p></dd></dl> + +<dl> +<dt><a name="index-make_002drect"></a>Scheme Procedure: <strong>make-rect</strong> <em><var>x</var> <var>y</var> <var>width</var> <var>height</var></em></dt> +<dd><p>Create a new rectangle with position (<var>x</var>, <var>y</var>), and +dimensions (<var>width</var>, <var>height</var>). +</p></dd></dl> + +<dl> +<dt><a name="index-null_002drect"></a>Scheme Variable: <strong>null-rect</strong></dt> +<dd><p>Rectangle with <code>x</code>, <code>y</code>, <code>width</code>, and <code>height</code> of 0. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_003f"></a>Scheme Syntax: <strong>rect?</strong> <em><var>obj</var></em></dt> +<dd><p>Return <code>#t</code> if <var>obj</var> is a rectangle. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dx"></a>Scheme Syntax: <strong>rect-x</strong> <em><var>rect</var></em></dt> +<dd><p>Return the x coordinate of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dy"></a>Scheme Syntax: <strong>rect-y</strong> <em><var>rect</var></em></dt> +<dd><p>Return the x coordinate of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dwidth"></a>Scheme Syntax: <strong>rect-width</strong> <em><var>rect</var></em></dt> +<dd><p>Return the width of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dheight"></a>Scheme Syntax: <strong>rect-height</strong> <em><var>rect</var></em></dt> +<dd><p>Return the height of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dleft"></a>Scheme Procedure: <strong>rect-left</strong> <em><var>rect</var></em></dt> +<dd><p>Return the left-hand x coordinate of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dright"></a>Scheme Procedure: <strong>rect-right</strong> <em><var>rect</var></em></dt> +<dd><p>Return the right-hand x coordinate of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dtop"></a>Scheme Procedure: <strong>rect-top</strong> <em><var>rect</var></em></dt> +<dd><p>Return the top y coordinate of <var>rect</var> +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dbottom"></a>Scheme Procedure: <strong>rect-bottom</strong> <em><var>rect</var></em></dt> +<dd><p>Return the bottom y coordinate of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dtop_002dleft"></a>Scheme Procedure: <strong>rect-top-left</strong> <em><var>rect</var></em></dt> +<dd><p>Return the top-left corner of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dtop_002dright"></a>Scheme Procedure: <strong>rect-top-right</strong> <em><var>rect</var></em></dt> +<dd><p>Return the top-right corner of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dbottom_002dleft"></a>Scheme Procedure: <strong>rect-bottom-left</strong> <em><var>rect</var></em></dt> +<dt><a name="index-rect_002dposition"></a>Scheme Procedure: <strong>rect-position</strong> <em><var>rect</var></em></dt> +<dd><p>Return the bottom-left corner of <var>rect</var> +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dbottom_002dright"></a>Scheme Procedure: <strong>rect-bottom-right</strong> <em><var>rect</var></em></dt> +<dd><p>Return the bottom-right corner of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dcenter_002dx"></a>Scheme Procedure: <strong>rect-center-x</strong> <em><var>rect</var></em></dt> +<dd><p>Return the center x coordinate of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dcenter_002dy"></a>Scheme Procedure: <strong>rect-center-y</strong> <em><var>rect</var></em></dt> +<dd><p>Return the center y coordinate of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dcenter"></a>Scheme Procedure: <strong>rect-center</strong> <em><var>rect</var></em></dt> +<dd><p>Return the center of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dhalf_002dwidth"></a>Scheme Procedure: <strong>rect-half-width</strong> <em><var>rect</var></em></dt> +<dd><p>Return the half width of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dhalf_002dheight"></a>Scheme Procedure: <strong>rect-half-height</strong> <em><var>rect</var></em></dt> +<dd><p>Return the half height of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dsize"></a>Scheme Procedure: <strong>rect-size</strong> <em><var>rect</var></em></dt> +<dd><p>Return the size of <var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dmove"></a>Scheme Procedure: <strong>rect-move</strong> <em><var>rect</var> <var>v</var></em></dt> +<dt><a name="index-rect_002dmove-1"></a>Scheme Procedure: <strong>rect-move</strong> <em><var>rect</var> <var>x</var> <var>y</var></em></dt> +<dd><p>Create a new rectangle by moving <var>rect</var> by the given 2D vector +offset <var>v</var>, or the coordinates <var>x</var> and <var>y</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dinflate"></a>Scheme Procedure: <strong>rect-inflate</strong> <em><var>rect</var> <var>size</var></em></dt> +<dt><a name="index-rect_002dinflate-1"></a>Scheme Procedure: <strong>rect-inflate</strong> <em><var>rect</var> <var>width</var> <var>height</var></em></dt> +<dd><p>Create a new rectangle by growing <var>rect</var> by the 2D vector +<var>size</var> (or <var>width</var> and <var>height</var>) without changing the +center point. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dunion"></a>Scheme Procedure: <strong>rect-union</strong> <em><var>rect1</var> <var>rect2</var></em></dt> +<dd><p>Create a new rectangle that covers the area of both <var>rect1</var> and +<var>rect2</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dclip"></a>Scheme Procedure: <strong>rect-clip</strong> <em><var>rect1</var> <var>rect2</var></em></dt> +<dd><p>Create a new rectangle that is the overlapping region of <var>rect1</var> +and <var>rect2</var>. If the rects do not overlap, a rect of size 0 is +returned. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dclamp"></a>Scheme Procedure: <strong>rect-clamp</strong> <em><var>rect</var> <var>v</var></em></dt> +<dd><p>Return a new 2D vector by constraining <var>v</var> to the bounds of +<var>rect</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dwithin_003f"></a>Scheme Procedure: <strong>rect-within?</strong> <em><var>rect1</var> <var>rect2</var></em></dt> +<dd><p>Return <code>#t</code> if <var>rect2</var> is completely within <var>rect1</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dintersects_003f"></a>Scheme Procedure: <strong>rect-intersects?</strong> <em><var>rect1</var> <var>rect2</var></em></dt> +<dd><p>Return <code>#t</code> if <var>rect2</var> overlaps <var>rect1</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-rect_002dcontains_003f"></a>Scheme Procedure: <strong>rect-contains?</strong> <em><var>rect</var> <var>v</var></em></dt> +<dt><a name="index-rect_002dcontains_003f-1"></a>Scheme Procedure: <strong>rect-contains?</strong> <em><var>rect</var> <var>x</var> <var>y</var></em></dt> +<dd><p>Return <code>#t</code> if the 2D vector <var>v</var> (or the coordinates <var>x</var> +and <var>y</var>) is within <var>rect</var>. +</p></dd></dl> + +<hr> +<div class="header"> +<p> +Next: <a href="Transforms.html#Transforms" accesskey="n" rel="next">Transforms</a>, Previous: <a href="Vectors.html#Vectors" accesskey="p" rel="prev">Vectors</a>, Up: <a href="Math.html#Math" accesskey="u" rel="up">Math</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index.html#Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |