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diff --git a/manuals/chickadee/Rendering-Engine.html b/manuals/chickadee/Rendering-Engine.html deleted file mode 100644 index 8f81fc6..0000000 --- a/manuals/chickadee/Rendering-Engine.html +++ /dev/null @@ -1,176 +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>Rendering Engine (The Chickadee Game Toolkit)</title> - -<meta name="description" content="Rendering Engine (The Chickadee Game Toolkit)" /> -<meta name="keywords" content="Rendering Engine (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="Audio.html" rel="next" title="Audio" /> -<link href="Render-Settings.html" rel="prev" title="Render Settings" /> -<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="Rendering-Engine"></span><div class="header"> -<p> -Previous: <a href="Render-Settings.html" accesskey="p" rel="prev">Render Settings</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="Rendering-Engine-1"></span><h4 class="subsection">5.3.17 Rendering Engine</h4> - -<p>The <code>(chickadee graphics engine)</code> module provides a Scheme -abstraction to the state of the GPU driver. When the Chickadee game -loop launches, it takes care to initialize the engine. All draw calls -and state changes happen within the context of this engine. -</p> -<p>Performing a custom draw call could look something like this: -</p> -<div class="lisp"> -<pre class="lisp"><span class="syntax-open">(</span><span class="syntax-symbol">with-graphics-state</span> <span class="syntax-open">(</span><span class="syntax-open">(</span><span class="syntax-symbol">g:blend-mode</span> <span class="syntax-symbol">blend:alpha</span><span class="syntax-close">)</span> - <span class="syntax-open">(</span><span class="syntax-symbol">g:texture-0</span> <span class="syntax-symbol">my-texture</span><span class="syntax-close">)</span><span class="syntax-close">)</span> - <span class="syntax-open">(</span><span class="syntax-symbol">shader-apply</span> <span class="syntax-symbol">my-shader</span> <span class="syntax-keyword">#:foo</span> <span class="syntax-symbol">1</span><span class="syntax-close">)</span><span class="syntax-close">)</span> -</pre></div> - -<span id="Render-States"></span><h4 class="subsubsection">5.3.17.1 Render States</h4> - -<p>Render states represent individual state values on the GPU. For -example, the current shader. As a naming convention, Chickadee -prefixes variables containing render states with <code>g:</code>. Render -states can be manipulated using the <code>with-graphics-state</code> macro. -</p> -<dl> -<dt id="index-with_002dgraphics_002dstate">Syntax: <strong>with-graphics-state</strong> <em>((name value) …) body …</em></dt> -<dd><p>Evaluate <var>body</var> with render states defined by <var>name</var> changed -to <var>value</var>. The render states are restored to their previous -values afterwards. -</p></dd></dl> - -<p>One additional piece of state that the rendering engine has, that is -not part of the GPU state, is the current projection matrix: -</p> -<dl> -<dt id="index-current_002dprojection">Procedure: <strong>current-projection</strong></dt> -<dd><p>Return the currently bound projection matrix (see <a href="Matrices.html">Matrices</a>). -</p></dd></dl> - -<dl> -<dt id="index-with_002dprojection">Syntax: <strong>with-projection</strong> <em>projection body …</em></dt> -<dd><p>Evaluate <var>body</var> with the current projection matrix bound to -<var>projection</var> (see <a href="Matrices.html">Matrices</a>). -</p></dd></dl> - -<span id="Rendering"></span><h4 class="subsubsection">5.3.17.2 Rendering</h4> - -<p>Chickadee likens a GPU draw call to a Scheme procedure call. A shader -(see <a href="Shaders.html">Shaders</a>) is like a procedure for the GPU to apply. Shaders -are passed arguments: The positional arguments are vertex array -attributes (see <a href="Buffers.html">Buffers</a>) and the keyword arguments correspond to -the shader’s uniform variables. Scheme uses <code>apply</code> to call a -procedure, so Chickadee uses <code>shader-apply</code> to call a shader. -</p> -<dl> -<dt id="index-shader_002dapply">Syntax: <strong>shader-apply</strong> <em>shader vertex-array [#:uniform-key uniform-value …]</em></dt> -<dt id="index-shader_002dapply_002a">Syntax: <strong>shader-apply*</strong> <em>shader vertex-array count [#:uniform-key uniform-value …]</em></dt> -<dd> -<p>Render <var>vertex-array</var> using <var>shader</var> with the uniform values -specified in the following keyword arguments. -</p> -<p>While <code>shader-apply</code> will draw every vertex in <var>vertex-array</var>, -<code>shader-apply*</code> will only draw <var>count</var> vertices. -</p></dd></dl> - -<dl> -<dt id="index-shader_002dapply_002finstanced">Syntax: <strong>shader-apply/instanced</strong> <em>shader vertex-array n [#:uniform-key uniform-value …]</em></dt> -<dt id="index-shader_002dapply_002finstanced-1">Syntax: <strong>shader-apply/instanced</strong> <em>shader vertex-array count n [#:uniform-key uniform-value …]</em></dt> -<dd> -<p>Render <var>vertex-array</var> <var>n</var> times using <var>shader</var> with the -uniform values specified in the following keyword arguments. -</p> -<p>Instanced rendering is very beneficial for rendering the same object -many times with only small differences for each one. For example, the -particle effects described in <a href="Particles.html">Particles</a> use instanced rendering. -</p> -<p>While <code>shader-apply/instanced</code> will draw every vertex in -<var>vertex-array</var>, <code>shader-apply*</code> will only draw <var>count</var> -vertices. -</p></dd></dl> - -<hr /> -<div class="header"> -<p> -Previous: <a href="Render-Settings.html" accesskey="p" rel="prev">Render Settings</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> |