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* Chickadee: (chickadee). Game programming toolkit for Guile.
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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>
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<a name="Lines-and-Shapes-1"></a>
<h4 class="subsection">2.3.4 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><a name="index-draw_002dline"></a>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><a name="index-draw_002dbezier_002dcurve"></a>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><a name="index-draw_002dbezier_002dpath"></a>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>
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