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diff --git a/manuals/chickadee/Particles.html b/manuals/chickadee/Particles.html deleted file mode 100644 index 116e2e6..0000000 --- a/manuals/chickadee/Particles.html +++ /dev/null @@ -1,252 +0,0 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> -<html> -<!-- Copyright (C) 2017-2023 David Thompson dthompson2@worcester.edu - -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 6.7, http://www.gnu.org/software/texinfo/ --> -<head> -<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> -<title>Particles (The Chickadee Game Toolkit)</title> - -<meta name="description" content="Particles (The Chickadee Game Toolkit)" /> -<meta name="keywords" content="Particles (The Chickadee Game Toolkit)" /> -<meta name="resource-type" content="document" /> -<meta name="distribution" content="global" /> -<meta name="Generator" content="makeinfo" /> -<link href="index.html" rel="start" title="Top" /> -<link href="Index.html" rel="index" title="Index" /> -<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents" /> -<link href="Graphics.html" rel="up" title="Graphics" /> -<link href="Tile-Maps.html" rel="next" title="Tile Maps" /> -<link href="Vector-Paths.html" rel="prev" title="Vector Paths" /> -<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="Particles"></span><div class="header"> -<p> -Next: <a href="Tile-Maps.html" accesskey="n" rel="next">Tile Maps</a>, Previous: <a href="Vector-Paths.html" accesskey="p" rel="prev">Vector Paths</a>, Up: <a href="Graphics.html" accesskey="u" rel="up">Graphics</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index.html" title="Index" rel="index">Index</a>]</p> -</div> -<hr /> -<span id="Particles-1"></span><h4 class="subsection">5.3.6 Particles</h4> - -<p>Effects like smoke, fire, sparks, etc. are often achieved by animating -lots of little, short-lived sprites known as “particles”. In fact, -all of these effects, and more, can be accomplished by turning a few -configuration knobs in a “particle system”. A particle system takes -care of managing the many miniscule moving morsels so the developer -can quickly produce an effect and move on with their life. The -<code>(chickadee graphics particles)</code> module provides an API for -manipulating particle systems. -</p> -<p>Below is an example of a very simple particle system that utilizes -nearly all of the default configuration settings: -</p> -<div class="lisp"> -<pre class="lisp"><span class="syntax-open">(</span><span class="syntax-symbol">use-modules</span> <span class="syntax-open">(</span><span class="syntax-symbol">chickadee</span> <span class="syntax-symbol">graphics</span> <span class="syntax-symbol">particles</span><span class="syntax-close">)</span><span class="syntax-close">)</span> -<span class="syntax-open">(</span><span class="syntax-special">define</span> <span class="syntax-symbol">texture</span> <span class="syntax-open">(</span><span class="syntax-symbol">load-image</span> <span class="syntax-string">"particle.png"</span><span class="syntax-close">)</span><span class="syntax-close">)</span> -<span class="syntax-open">(</span><span class="syntax-special">define</span> <span class="syntax-symbol">particles</span> <span class="syntax-open">(</span><span class="syntax-symbol">make-particles</span> <span class="syntax-symbol">2000</span> <span class="syntax-keyword">#:texture</span> <span class="syntax-symbol">texture</span><span class="syntax-close">)</span><span class="syntax-close">)</span> -</pre></div> - -<p>In order to put particles into a particle system, a particle -“emitter” is needed. Emitters know where to spawn new particles, -how many of them to spawn, and for how long they should do it. -</p> -<p>Below is an example of an emitter that spawns 16 particles per frame -at the coordinates <code>(320, 240)</code>: -</p> -<div class="lisp"> -<pre class="lisp"><span class="syntax-open">(</span><span class="syntax-symbol">use-modules</span> <span class="syntax-open">(</span><span class="syntax-symbol">chickadee</span> <span class="syntax-symbol">math</span> <span class="syntax-symbol">rect</span><span class="syntax-close">)</span><span class="syntax-close">)</span> -<span class="syntax-open">(</span><span class="syntax-special">define</span> <span class="syntax-symbol">emitter</span> <span class="syntax-open">(</span><span class="syntax-symbol">make-particle-emitter</span> <span class="syntax-open">(</span><span class="syntax-symbol">make-rect</span> <span class="syntax-symbol">0.0</span> <span class="syntax-symbol">0.0</span> <span class="syntax-symbol">320.0</span> <span class="syntax-symbol">240.0</span><span class="syntax-close">)</span> <span class="syntax-symbol">16</span><span class="syntax-close">)</span><span class="syntax-close">)</span> -<span class="syntax-open">(</span><span class="syntax-symbol">add-particle-emitter</span> <span class="syntax-symbol">particles</span> <span class="syntax-symbol">emitter</span><span class="syntax-close">)</span> -</pre></div> - -<p>To see all of the tweakable knobs and switches, read on! -</p> -<dl> -<dt id="index-make_002dparticles">Procedure: <strong>make-particles</strong> <em>capacity [#:blend-mode] [#:color white] [#:end-color transparent] [#:texture] [#:animation-rows 1] [#:animation-columns 1] [#:width] [#:height] [#:speed-range (vec2 0.1 1.0)] [#:acceleration-range (vec2 0.0 0.1)] [#:direction-range (vec2 0 (* 2 pi))] [#:lifetime 30] [#:sort]</em></dt> -<dd> -<p>Return a new particle system that may contain up to <var>capacity</var> -particles. Achieving the desired particle effect involves tweaking -the following keyword arguments as needed: -</p> -<p>- <var>blend-mode</var>: Pixel blending mode. Alpha blending is used by -default. (see <a href="Render-Settings.html">Render Settings</a> for more about blend modes). -</p> -<p>- <var>start-color</var>: The tint color of the particle at the beginning of its -life. White by default. -</p> -<p>- <var>end-color</var>: The tint color of the particle at the end of of its -life. Completely transparent by default for a fade-out effect. The -color in the middle of a particle’s life will be an interpolation of -<var>start-color</var> and <var>end-color</var>. -</p> -<p>- <var>texture</var>: The texture applied to the particles. The texture -may be subdivided into many animation frames. -</p> -<p>- <var>animation-rows</var>: How many animation frame rows there are in the -texture. Default is 1. -</p> -<p>- <var>animation-columns</var>: How many animation frame columns there are -in the texture. Default is 1. -</p> -<p>- <var>width</var>: The width of each particle. By default, the width of -an animation frame (in pixels) is used. -</p> -<p>- <var>height</var>: The height of each particle. By default, the height -of an animation frame (in pixels) is used. -</p> -<p>- <var>speed-range</var>: A 2D vector containing the min and max particle -speed. Each particle will have a speed chosen at random from this -range. By default, speed ranges from 0.1 to 1.0. -</p> -<p>- <var>acceleration-range</var>: A 2D vector containing the min and max -particle acceleration. Each particle will have an acceleration chosen -at random from this range. By default, acceleration ranges from 0.0 -to 0.1. -</p> -<p>- <var>direction-range</var>: A 2D vector containing the min and max -particle direction as an angle in radians. Each particle will have a -direction chosen at random from this range. By default, the range -covers all possible angles. -</p> -<p>- <var>lifetime</var>: How long each particle lives, measured in -updates. 30 by default. -</p> -<p>- <var>sort</var>: <code>youngest</code> if youngest particle should be drawn -last or <code>oldest</code> for the reverse. By default, no sorting is -applied at all. -</p></dd></dl> - -<dl> -<dt id="index-particles_003f">Procedure: <strong>particles?</strong> <em>obj</em></dt> -<dd><p>Return <code>#t</code> if <var>obj</var> is a particle system. -</p></dd></dl> - -<dl> -<dt id="index-update_002dparticles">Procedure: <strong>update-particles</strong> <em>particles</em></dt> -<dd><p>Advance the simulation of <var>particles</var>. -</p></dd></dl> - -<dl> -<dt id="index-draw_002dparticles">Procedure: <strong>draw-particles</strong> <em>particles</em></dt> -<dd><p>Render <var>particles</var>. -</p></dd></dl> - -<dl> -<dt id="index-draw_002dparticles_002a">Procedure: <strong>draw-particles*</strong> <em>particles matrix</em></dt> -<dd><p>Render <var>particles</var> with <var>matrix</var> applied. -</p></dd></dl> - -<dl> -<dt id="index-make_002dparticle_002demitter">Procedure: <strong>make-particle-emitter</strong> <em>spawn-area rate [duration]</em></dt> -<dd> -<p>Return a new particle emitter that spawns <var>rate</var> particles per -frame within <var>spawn-area</var> (a rectangle or 2D vector) for -<var>duration</var> frames. If <var>duration</var> is not specified, the -emitter will spawn particles indefinitely. -</p></dd></dl> - -<dl> -<dt id="index-particle_002demitter_003f">Procedure: <strong>particle-emitter?</strong> <em>obj</em></dt> -<dd><p>Return <code>#t</code> if <var>obj</var> is a particle emitter. -</p></dd></dl> - -<dl> -<dt id="index-particle_002demitter_002dspawn_002darea">Procedure: <strong>particle-emitter-spawn-area</strong> <em>emitter</em></dt> -<dd><p>Return the spawn area for <var>emitter</var>. -</p></dd></dl> - -<dl> -<dt id="index-particle_002demitter_002drate">Procedure: <strong>particle-emitter-rate</strong> <em>emitter</em></dt> -<dd><p>Return the number of particles that <var>emitter</var> will spawn per -frame. -</p></dd></dl> - -<dl> -<dt id="index-particle_002demitter_002dlife">Procedure: <strong>particle-emitter-life</strong> <em>emitter</em></dt> -<dd><p>Return the number of frames remaining in <var>emitter</var>’s lifespan. -</p></dd></dl> - -<dl> -<dt id="index-particle_002demitter_002ddone_003f">Procedure: <strong>particle-emitter-done?</strong> <em>emitter</em></dt> -<dd><p>Return <code>#t</code> if <var>emitter</var> has finished spawning particlces. -</p></dd></dl> - -<dl> -<dt id="index-add_002dparticle_002demitter">Procedure: <strong>add-particle-emitter</strong> <em>particles emitter</em></dt> -<dd><p>Add <var>emitter</var> to <var>particles</var>. -</p></dd></dl> - -<dl> -<dt id="index-remove_002dparticle_002demitter">Procedure: <strong>remove-particle-emitter</strong> <em>particles emitter</em></dt> -<dd><p>Remove <var>emitter</var> from <var>particles</var> -</p></dd></dl> - -<hr /> -<div class="header"> -<p> -Next: <a href="Tile-Maps.html" accesskey="n" rel="next">Tile Maps</a>, Previous: <a href="Vector-Paths.html" accesskey="p" rel="prev">Vector Paths</a>, Up: <a href="Graphics.html" accesskey="u" rel="up">Graphics</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index.html" title="Index" rel="index">Index</a>]</p> -</div> - - - -</body> -</html> |