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diff --git a/manuals/chickadee/Render-Settings.html b/manuals/chickadee/Render-Settings.html new file mode 100644 index 0000000..fe3fa98 --- /dev/null +++ b/manuals/chickadee/Render-Settings.html @@ -0,0 +1,512 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 2017-2021 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 6.7, http://www.gnu.org/software/texinfo/ --> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<title>Render Settings (The Chickadee Game Toolkit)</title> + +<meta name="description" content="Render Settings (The Chickadee Game Toolkit)"> +<meta name="keywords" content="Render Settings (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="Rendering-Engine.html" rel="next" title="Rendering Engine"> +<link href="Viewports.html" rel="prev" title="Viewports"> +<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="Render-Settings"></span><div class="header"> +<p> +Next: <a href="Rendering-Engine.html" accesskey="n" rel="next">Rendering Engine</a>, Previous: <a href="Viewports.html" accesskey="p" rel="prev">Viewports</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="Render-Settings-1"></span><h4 class="subsection">5.3.16 Render Settings</h4> + +<span id="Blending"></span><h4 class="subsubsection">5.3.16.1 Blending</h4> + +<p>Rendering a scene often involves drawing layers of objects that +overlap each other. Blending determines how two overlapping pixels +are combined in the final image that is rendered to the screen. The +<code>(chickadee graphics blend)</code> module provides a data type for +blending modes. +</p> +<p>Chickadee provides the following blend modes: +</p> +<dl> +<dt id="index-blend_003aalpha">Variable: <strong>blend:alpha</strong></dt> +<dd><p>Blend pixels according to the values of their alpha channels. This is +the most commonly used blend mode. +</p></dd></dl> + +<dl> +<dt id="index-blend_003areplace">Variable: <strong>blend:replace</strong></dt> +<dd><p>Overwrite the output pixel color with the color being drawn. +</p></dd></dl> + +<dl> +<dt id="index-blend_003aadd">Variable: <strong>blend:add</strong></dt> +<dd><p>Add all pixel color values together. The more colors blended +together, the more white the final color becomes. +</p></dd></dl> + +<dl> +<dt id="index-blend_003asubtract">Variable: <strong>blend:subtract</strong></dt> +<dd><p>Subtract all pixel color values. The more colors blended together, +the more black the final color becomes. +</p></dd></dl> + +<dl> +<dt id="index-blend_003amultiply">Variable: <strong>blend:multiply</strong></dt> +</dl> + +<dl> +<dt id="index-blend_003adarken">Variable: <strong>blend:darken</strong></dt> +</dl> + +<dl> +<dt id="index-blend_003alighten">Variable: <strong>blend:lighten</strong></dt> +</dl> + +<dl> +<dt id="index-blend_003ascreen">Variable: <strong>blend:screen</strong></dt> +</dl> + +<p>Custom blend modes can be created using the <code>make-blend-mode</code> procedure: +</p> +<dl> +<dt id="index-make_002dblend_002dmode">Procedure: <strong>make-blend-mode</strong> <em>equation source-function destination-function</em></dt> +<dd><p>Return a new custom blend mode that applies <var>source-function</var> to +the source color, <var>destination-function</var> to the destination color, +and finally applies <var>equation</var> to the transformed +source/destination color values. These arguments are <em>not</em> +procedures, but symbolic representations of the functions that OpenGL +supports. +</p> +<p>Valid values for <var>equation</var> are: +</p> +<ul> +<li> <code>add</code> +</li><li> <code>subtract</code> +</li><li> <code>reverse-subtract</code> +</li><li> <code>min</code> +</li><li> <code>max</code> +</li><li> <code>alpha-min</code> +</li><li> <code>alpha-max</code> +</li></ul> + +<p>Valid values for <var>source-function</var> are: +</p> +<ul> +<li> <code>zero</code> +</li><li> <code>one</code> +</li><li> <code>destination-color</code> +</li><li> <code>one-minus-destination-color</code> +</li><li> <code>source-alpha-saturate</code> +</li><li> <code>source-alpha</code> +</li><li> <code>one-minus-source-alpha</code> +</li><li> <code>destination-alpha</code> +</li><li> <code>one-minus-destination-alpha</code> +</li><li> <code>constant-color</code> +</li><li> <code>one-minus-constant-color</code> +</li><li> <code>constant-alpha</code> +</li><li> <code>one-minus-constant-alpha</code> +</li></ul> + +<p>Valid values for <var>destination-function</var> are: +</p> +<ul> +<li> <code>zero</code> +</li><li> <code>one</code> +</li><li> <code>source-color</code> +</li><li> <code>one-minus-source-color</code> +</li><li> <code>source-alpha</code> +</li><li> <code>one-minus-source-alpha</code> +</li><li> <code>destination-alpha</code> +</li><li> <code>one-minus-destination-alpha</code> +</li><li> <code>constant-color</code> +</li><li> <code>one-minus-constant-color</code> +</li><li> <code>constant-alpha</code> +</li><li> <code>one-minus-constant-alpha</code> +</li></ul> + +</dd></dl> + +<span id="Polygon-Modes-and-Culling"></span><h4 class="subsubsection">5.3.16.2 Polygon Modes and Culling</h4> + +<p>The <code>(chickadee graphics polygon)</code> module provides access to the +<code>g:polygon-mode</code> and <code>g:cull-face-mode</code> render states. +</p> +<dl> +<dt id="index-fill_002dpolygon_002dmode">Variable: <strong>fill-polygon-mode</strong></dt> +<dd><p>Completely fill in the polygon. This is the default mode. +</p></dd></dl> + +<dl> +<dt id="index-line_002dpolygon_002dmode">Variable: <strong>line-polygon-mode</strong></dt> +<dd><p>Render only the edges of the polygon. Produces a wireframe. +</p></dd></dl> + +<dl> +<dt id="index-point_002dpolygon_002dmode">Variable: <strong>point-polygon-mode</strong></dt> +<dd><p>Render only the vertex positions as points. +</p></dd></dl> + +<dl> +<dt id="index-make_002dpolygon_002dmode">Procedure: <strong>make-polygon-mode</strong> <em>front back</em></dt> +<dd><p>Return a new polygon mode that uses the method <var>front</var> for the +front face and <var>back</var> for the back face. The valid modes are +<code>fill</code>, <code>line</code>, and <var>point</var>. +</p></dd></dl> + +<dl> +<dt id="index-polygon_002dmode_003f">Procedure: <strong>polygon-mode?</strong> <em>obj</em></dt> +<dd><p>Return <code>#t</code> if <var>obj</var> is a polygon mode. +</p></dd></dl> + +<dl> +<dt id="index-current_002dpolygon_002dmode">Procedure: <strong>current-polygon-mode</strong></dt> +<dd><p>Return the current polygon mode. +</p></dd></dl> + +<dl> +<dt id="index-g_003apolygon_002dmode">Variable: <strong>g:polygon-mode</strong></dt> +<dd><p>Render state for polygon modes (see <a href="Rendering-Engine.html">Rendering Engine</a>.) +</p></dd></dl> + +<dl> +<dt id="index-no_002dcull_002dface_002dmode">Variable: <strong>no-cull-face-mode</strong></dt> +<dd><p>Don’t cull any faces. +</p></dd></dl> + +<dl> +<dt id="index-back_002dcull_002dface_002dmode">Variable: <strong>back-cull-face-mode</strong></dt> +<dd><p>Cull only back faces. +</p></dd></dl> + +<dl> +<dt id="index-front_002dcull_002dface_002dmode">Variable: <strong>front-cull-face-mode</strong></dt> +<dd><p>Cull only front faces. +</p></dd></dl> + +<dl> +<dt id="index-front_002dand_002dback_002dcull_002dface_002dmode">Variable: <strong>front-and-back-cull-face-mode</strong></dt> +<dd><p>Cull both front and back faces. +</p></dd></dl> + +<dl> +<dt id="index-cull_002dface_002dmode_003f">Procedure: <strong>cull-face-mode?</strong> <em>obj</em></dt> +<dd><p>Return <code>#t</code> if <var>obj</var> is a cull face mode. +</p></dd></dl> + +<dl> +<dt id="index-cull_002dface_002dmode_002dfront_003f">Procedure: <strong>cull-face-mode-front?</strong> <em>cull-face-mode</em></dt> +<dd><p>Return <code>#t</code> if <var>cull-face-mode</var> culls front faces. +</p></dd></dl> + +<dl> +<dt id="index-cull_002dface_002dmode_002dback_003f">Procedure: <strong>cull-face-mode-back?</strong> <em>cull-face-mode</em></dt> +<dd><p>Return <code>#t</code> if <var>cull-face-mode</var> culls back faces. +</p></dd></dl> + +<dl> +<dt id="index-current_002dcull_002dface_002dmode">Procedure: <strong>current-cull-face-mode</strong></dt> +<dd><p>Return the current cull face mode. +</p></dd></dl> + +<dl> +<dt id="index-g_003acull_002dface_002dmode">Variable: <strong>g:cull-face-mode</strong></dt> +<dd><p>Render state for cull face modes (see <a href="Rendering-Engine.html">Rendering Engine</a>.) +</p></dd></dl> + +<span id="Depth-Testing"></span><h4 class="subsubsection">5.3.16.3 Depth Testing</h4> + +<p>The <code>(chickadee graphics depth)</code> module provides access to the +<code>g:depth-test</code> render state. +</p> +<dl> +<dt id="index-make_002ddepth_002dtest">Procedure: <strong>make-depth-test</strong> <em>[#:write? #t] [#:function 'less-than] [#:near 0.0] [#:far 1.0]</em></dt> +<dd> +<p>Return a new depth test object. If <var>write</var> is <code>#t</code>, the +depth buffer will be written to during a draw call. <var>near</var> and +<var>far</var> define the min/max Z values for which depth testing may +pass. +</p> +<p><var>function</var> specifies how the depth value of pixel being drawn +compares to the depth value that is already in the depth buffer. When +this comparison is true, the depth test passes and the pixel is drawn. +When it fails, the pixel is discarded. +</p> +<p>The possible values of <var>function</var> are: +</p> +<ul> +<li> <code>always</code> +</li><li> <code>never</code> +</li><li> <code>equal</code> +</li><li> <code>not-equal</code> +</li><li> <code>less-than</code> +</li><li> <code>less-than-or-equal</code> +</li><li> <code>greater-than</code> +</li><li> <code>greater-than-or-equal</code> +</li></ul> + +</dd></dl> + +<dl> +<dt id="index-depth_002dtest_003f">Procedure: <strong>depth-test?</strong> <em>obj</em></dt> +<dd><p>Return <code>#t</code> when <var>obj</var> is a depth test object. +</p></dd></dl> + +<dl> +<dt id="index-depth_002dtest_002dwrite_003f">Procedure: <strong>depth-test-write?</strong> <em>depth-test</em></dt> +<dd><p>Return <code>#t</code> when <var>depth-test</var> will write to the depth buffer. +</p></dd></dl> + +<dl> +<dt id="index-depth_002dtest_002dfunction">Procedure: <strong>depth-test-function</strong> <em>depth-test</em></dt> +<dd><p>Return the comparison function of <var>depth-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-depth_002dtest_002dnear">Procedure: <strong>depth-test-near</strong> <em>depth-test</em></dt> +<dd><p>Return the near Z value of <var>depth-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-depth_002dtest_002dfar">Procedure: <strong>depth-test-far</strong> <em>depth-test</em></dt> +<dd><p>Return the far Z value of <var>depth-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-current_002ddepth_002dtest">Procedure: <strong>current-depth-test</strong></dt> +<dd><p>Return the current depth test. +</p></dd></dl> + +<dl> +<dt id="index-g_003adepth_002dtest">Variable: <strong>g:depth-test</strong></dt> +<dd><p>Render state for depth tests (see <a href="Rendering-Engine.html">Rendering Engine</a>.) +</p></dd></dl> + +<span id="Stencil-Testing"></span><h4 class="subsubsection">5.3.16.4 Stencil Testing</h4> + +<p>The <code>(chickadee graphics stencil)</code> module provides access to the +<code>g:stencil-test</code> render state. +</p> +<dl> +<dt id="index-default_002dstencil_002dtest">Variable: <strong>default-stencil-test</strong></dt> +<dd><p>A stencil test that always passes. +</p></dd></dl> + +<dl> +<dt id="index-make_002dstencil_002dtest">Procedure: <strong>make-stencil-test</strong> <em>[#:mask #xFF] [#:function always] [#:function-mask #xFF] [#:reference 0] [#:on-fail keep] [#:on-depth-fail keep] [#:on-pass keep] [#:mask-front mask] [#:mask-back mask] [#:function-mask-front function-mask] [#:function-mask-back function-mask] [#:refrence-front reference] [#:reference-back reference] [#:on-fail-front on-fail] [#:on-fail-back on-fail] [#:on-depth-fail-front on-depth-fail] [#:on-depth-fail-back on-depth-fail] [#:on-pass-front on-pass] [#:on-pass-back on-pass]</em></dt> +<dd> +<p>Return a new stencil test object. Different configurations can be +used for the front and back faces by using the arguments that end in +“front” or “back”. +</p> +<p>Valid values for <var>on-pass</var>, <var>on-fail</var>, and <var>on-depth-fail</var> +are: +</p> +<ul> +<li> <code>zero</code> +</li><li> <code>keep</code> +</li><li> <code>replace</code> +</li><li> <code>increment</code> +</li><li> <code>increment-wrap</code> +</li><li> <code>decrement</code> +</li><li> <code>decrement-wrap</code> +</li><li> <code>invert</code> +</li></ul> + +<p>Valid values for <var>function</var> are: +</p> +<ul> +<li> <code>always</code> +</li><li> <code>never</code> +</li><li> <code>equal</code> +</li><li> <code>not-equal</code> +</li><li> <code>less-than</code> +</li><li> <code>less-than-or-equal</code> +</li><li> <code>greater-than</code> +</li><li> <code>greater-than-or-equal</code> +</li></ul> + +</dd></dl> + +<dl> +<dt id="index-stencil_002dtest_003f">Procedure: <strong>stencil-test?</strong> <em>obj</em></dt> +<dd><p>Return <code>#t</code> when <var>obj</var> is a stencil test object. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002dmask_002dfront">Procedure: <strong>stencil-test-mask-front</strong> <em>stencil-test</em></dt> +<dd><p>Return the front mask of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002dmask_002dback">Procedure: <strong>stencil-test-mask-back</strong> <em>stencil-test</em></dt> +<dd><p>Return the back mask of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002dfunction_002dfront">Procedure: <strong>stencil-test-function-front</strong> <em>stencil-test</em></dt> +<dd><p>Return the front function of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002dfunction_002dback">Procedure: <strong>stencil-test-function-back</strong> <em>stencil-test</em></dt> +<dd><p>Return the back function of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002dfunction_002dmask_002dfront">Procedure: <strong>stencil-test-function-mask-front</strong> <em>stencil-test</em></dt> +<dd><p>Return the front function-mask of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002dfunction_002dmask_002dback">Procedure: <strong>stencil-test-function-mask-back</strong> <em>stencil-test</em></dt> +<dd><p>Return the back function-mask of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002dreference_002dfront">Procedure: <strong>stencil-test-reference-front</strong> <em>stencil-test</em></dt> +<dd><p>Return the front reference value of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002dreference_002dback">Procedure: <strong>stencil-test-reference-back</strong> <em>stencil-test</em></dt> +<dd><p>Return the back reference value of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002don_002dfail_002dfront">Procedure: <strong>stencil-test-on-fail-front</strong> <em>stencil-test</em></dt> +<dd><p>Return the front failure action of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002don_002dfail_002dback">Procedure: <strong>stencil-test-on-fail-back</strong> <em>stencil-test</em></dt> +<dd><p>Return the back failure action of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002don_002ddepth_002dfail_002dfront">Procedure: <strong>stencil-test-on-depth-fail-front</strong> <em>stencil-test</em></dt> +<dd><p>Return the front depth test failure action of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002don_002ddepth_002dfail_002dback">Procedure: <strong>stencil-test-on-depth-fail-back</strong> <em>stencil-test</em></dt> +<dd><p>Return the back depth test failure action of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002don_002dpass_002dfront">Procedure: <strong>stencil-test-on-pass-front</strong> <em>stencil-test</em></dt> +<dd><p>Return the front pass action of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-stencil_002dtest_002don_002dpass_002dback">Procedure: <strong>stencil-test-on-pass-back</strong> <em>stencil-test</em></dt> +<dd><p>Return the back pass action of <var>stencil-test</var>. +</p></dd></dl> + +<dl> +<dt id="index-current_002dstencil_002dtest">Procedure: <strong>current-stencil-test</strong></dt> +<dd><p>Return the current stencil test. +</p></dd></dl> + +<dl> +<dt id="index-g_003astencil_002dtest">Variable: <strong>g:stencil-test</strong></dt> +<dd><p>Render state for stencil testing (see <a href="Rendering-Engine.html">Rendering Engine</a>.) +</p></dd></dl> + +<span id="Multisample-Antialiasing"></span><h4 class="subsubsection">5.3.16.5 Multisample Antialiasing</h4> + +<p>Multisample antialiasing is a feature supported by many, but not all, +graphics cards. It is a nice easy way to improve the final frame that +the user sees, particularly in 3D scenes. The <code>(chickadee +graphics multisample)</code> module provides access to the +<code>g:multisample?</code> render state. +</p> +<dl> +<dt id="index-current_002dmultisample">Procedure: <strong>current-multisample</strong></dt> +<dd><p>Return <code>#t</code> if multisampling is enabled. +</p></dd></dl> + +<dl> +<dt id="index-g_003amultisample_003f">Variable: <strong>g:multisample?</strong></dt> +<dd><p>Render state for multisampling (see <a href="Rendering-Engine.html">Rendering Engine</a>.) +</p></dd></dl> + +<hr> +<div class="header"> +<p> +Next: <a href="Rendering-Engine.html" accesskey="n" rel="next">Rendering Engine</a>, Previous: <a href="Viewports.html" accesskey="p" rel="prev">Viewports</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> |