1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- Copyright (C) 2017-2020 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.
* Chickadee: (chickadee). Game programming toolkit for Guile.
The document was typeset with
http://www.texinfo.org/ (GNU Texinfo).
-->
<!-- Created by GNU Texinfo 6.6, http://www.gnu.org/software/texinfo/ -->
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Lines and Shapes (The Chickadee Game Toolkit)</title>
<meta name="description" content="Lines and Shapes (The Chickadee Game Toolkit)">
<meta name="keywords" content="Lines and Shapes (The Chickadee Game Toolkit)">
<meta name="resource-type" content="document">
<meta name="distribution" content="global">
<meta name="Generator" content="makeinfo">
<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="Graphics.html#Graphics" rel="up" title="Graphics">
<link href="Fonts.html#Fonts" rel="next" title="Fonts">
<link href="Tile-Maps.html#Tile-Maps" rel="prev" title="Tile Maps">
<style type="text/css">
<!--
a.summary-letter {text-decoration: none}
blockquote.indentedblock {margin-right: 0em}
div.display {margin-left: 3.2em}
div.example {margin-left: 3.2em}
div.lisp {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}
span.nolinebreak {white-space: nowrap}
span.roman {font-family: initial; font-weight: normal}
span.sansserif {font-family: sans-serif; font-weight: normal}
ul.no-bullet {list-style: none}
@media (min-width: 1140px) {
body {
margin-left: 14rem;
margin-right: 4rem;
max-width: 52rem;
}
}
@media (min-width: 800px) and (max-width: 1140px) {
body {
margin-left: 6rem;
margin-right: 4rem;
max-width: 52rem;
}
}
@media (max-width: 800px) {
body {
margin: 1rem;
}
}
-->
</style>
<link rel="stylesheet" type="text/css" href="https://dthompson.us/css/dthompson.css">
</head>
<body lang="en">
<span id="Lines-and-Shapes"></span><div class="header">
<p>
Next: <a href="Fonts.html#Fonts" accesskey="n" rel="next">Fonts</a>, Previous: <a href="Tile-Maps.html#Tile-Maps" accesskey="p" rel="prev">Tile Maps</a>, Up: <a href="Graphics.html#Graphics" accesskey="u" rel="up">Graphics</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>
<span id="Lines-and-Shapes-1"></span><h4 class="subsection">2.3.5 Lines and Shapes</h4>
<p>Sprites are fun, but sometimes simple, untextured lines and polygons
are desired. That’s where the <code>(chickadee render shapes)</code> module
comes in!
</p>
<dl>
<dt id="index-draw_002dline">Procedure: <strong>draw-line</strong> <em>start end [#:thickness 0.5] [#:feather 1.0] [#:cap round] [#:color] [#:shader]</em></dt>
<dd>
<p>Draw a line segment from <var>start</var> to <var>end</var>. The line will be
<var>thickness</var> pixels thick with an antialiased border <var>feather</var>
pixels wide. The line will be colored <var>color</var>. <var>cap</var>
specifies the type of end cap that should be used to terminate the
lines, either <code>none</code>, <code>butt</code>, <code>square</code>, <code>round</code>,
<code>triangle-in</code>, or <code>triangle-out</code>. Advanced users may use
the <var>shader</var> argument to override the built-in line segment
shader.
</p></dd></dl>
<dl>
<dt id="index-draw_002dbezier_002dcurve">Procedure: <strong>draw-bezier-curve</strong> <em>bezier [#:segments 32] [#:control-points?] [#:tangents?] [#:control-point-size 8] [#:control-point-color yellow] [#:tangent-color yellow] [#:thickness 0.5] [#:feather 1.0] [#:matrix]</em></dt>
<dd>
<p>Draw the curve defined by <var>bezier</var> using a resolution of N
<var>segments</var>. When <var>control-points?</var> is <code>#t</code>, the control
points are rendered as squares of size <var>control-point-size</var> pixels
and a color of <var>control-point-color</var>. When <var>tangents?</var> is
<code>#t</code>, the tangent lines from terminal point to control point are
rendered using the color <var>tangent-color</var>.
</p>
<p>All line segments rendered use <code>draw-line</code>, and thus the
arguments <var>thickness</var> and <var>feather</var> have the same effect as in
that procedure.
</p>
<p>A custom <var>matrix</var> may be passed for applications that require more
control over the final output.
</p></dd></dl>
<dl>
<dt id="index-draw_002dbezier_002dpath">Procedure: <strong>draw-bezier-path</strong> <em>path [#:segments 32] [#:control-points?] [#:tangents?] [#:control-point-size 8] [#:control-point-color yellow] [#:tangent-color yellow] [#:thickness 0.5] [#:feather 1.0] [#:matrix]</em></dt>
<dd>
<p>Render <var>path</var>, a list of bezier curves. See the documentation for
<code>draw-bezier-curve</code> for an explanation of all the keyword
arguments.
</p></dd></dl>
</body>
</html>
|
