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diff --git a/manuals/chickadee/Viewports.html b/manuals/chickadee/Viewports.html index 2e46d12..15b3940 100644 --- a/manuals/chickadee/Viewports.html +++ b/manuals/chickadee/Viewports.html @@ -1,6 +1,6 @@ <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> -<!-- Copyright (C) 2017 David Thompson davet@gnu.org +<!-- Copyright (C) 2017, 2018, 2019 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 @@ -13,6 +13,8 @@ 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). --> @@ -30,7 +32,7 @@ http://www.texinfo.org/ (GNU Texinfo). <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="Scripting.html#Scripting" rel="next" title="Scripting"> +<link href="Rendering-Engine.html#Rendering-Engine" rel="next" title="Rendering Engine"> <link href="Framebuffers.html#Framebuffers" rel="prev" title="Framebuffers"> <style type="text/css"> <!-- @@ -90,11 +92,71 @@ ul.no-bullet {list-style: none} <a name="Viewports"></a> <div class="header"> <p> -Previous: <a href="Framebuffers.html#Framebuffers" accesskey="p" rel="prev">Framebuffers</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> +Next: <a href="Rendering-Engine.html#Rendering-Engine" accesskey="n" rel="next">Rendering Engine</a>, Previous: <a href="Framebuffers.html#Framebuffers" accesskey="p" rel="prev">Framebuffers</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> <a name="Viewports-1"></a> -<h4 class="subsection">2.3.11 Viewports</h4> +<h4 class="subsection">2.3.9 Viewports</h4> + +<p>A viewport represents a subset of the screen (or framebuffer). When +rendering a frame, the resulting image will only appear within that +viewport. These aren’t often needed, and Chickadee’s default viewport +occupies the entire screen, but there are certain situations where +they are useful. For example, a split-screen multiplayer game may +render to two different viewports, each occupying a different half of +the screen. For information about how to set the current viewport, +see <code>with-viewport</code> in <a href="Rendering-Engine.html#Rendering-Engine">Rendering Engine</a>. +</p> +<p>The <code>(chickadee render viewport)</code> module provides the following +API: +</p> +<dl> +<dt><a name="index-make_002dviewport"></a>Procedure: <strong>make-viewport</strong> <em>x y width height [#:clear-color] [#:clear-flags]</em></dt> +<dd> +<p>Create a viewport that covers an area of the window starting from +coordinates (<var>x</var>, <var>y</var>) and spanning <var>width</var> <code>x</code> +<var>height</var> pixels. Fill the viewport with <var>clear-color</var> when +clearing the screen. Clear the buffers denoted by the list of symbols +in <var>clear-flags</var>. +</p> +<p>Possible values for <var>clear-flags</var> are <var>color-buffer</var>, +<var>depth-buffer</var>, <var>accum-buffer</var>, and <var>stencil-buffer</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-viewport_003f"></a>Procedure: <strong>viewport?</strong> <em>obj</em></dt> +<dd><p>Return <code>#t</code> if <var>obj</var> is a viewport. +</p></dd></dl> + +<dl> +<dt><a name="index-viewport_002dx"></a>Procedure: <strong>viewport-x</strong> <em>viewport</em></dt> +<dd><p>Return the left edge of <var>viewport</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-viewport_002dy"></a>Procedure: <strong>viewport-y</strong> <em>viewport</em></dt> +<dd><p>Return the bottom edge of <var>viewport</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-viewport_002dwidth"></a>Procedure: <strong>viewport-width</strong> <em>viewport</em></dt> +<dd><p>Return the width of <var>viewport</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-viewport_002dheight"></a>Procedure: <strong>viewport-height</strong> <em>viewport</em></dt> +<dd><p>Return the height of <var>viewport</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-viewport_002dclear_002dcolor"></a>Procedure: <strong>viewport-clear-color</strong> <em>viewport</em></dt> +<dd><p>Return the clear color for <var>viewport</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-viewport_002dclear_002dflags"></a>Procedure: <strong>viewport-clear-flags</strong> <em>viewport</em></dt> +<dd><p>Return the list of clear flags for <var>viewport</var>. +</p></dd></dl> |