--- /dev/null
+ GNU GENERAL PUBLIC LICENSE
+ Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The licenses for most software are designed to take away your
+freedom to share and change it. By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users. This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it. (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.) You can apply it to
+your programs, too.
+
+ When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+ To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+ For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have. You must make sure that they, too, receive or can get the
+source code. And you must show them these terms so they know their
+rights.
+
+ We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+ Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software. If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+ Finally, any free program is threatened constantly by software
+patents. We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary. To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+ The precise terms and conditions for copying, distribution and
+modification follow.
+
+ GNU GENERAL PUBLIC LICENSE
+ TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+ 0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License. The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language. (Hereinafter, translation is included without limitation in
+the term "modification".) Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope. The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+ 1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+ 2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+ a) You must cause the modified files to carry prominent notices
+ stating that you changed the files and the date of any change.
+
+ b) You must cause any work that you distribute or publish, that in
+ whole or in part contains or is derived from the Program or any
+ part thereof, to be licensed as a whole at no charge to all third
+ parties under the terms of this License.
+
+ c) If the modified program normally reads commands interactively
+ when run, you must cause it, when started running for such
+ interactive use in the most ordinary way, to print or display an
+ announcement including an appropriate copyright notice and a
+ notice that there is no warranty (or else, saying that you provide
+ a warranty) and that users may redistribute the program under
+ these conditions, and telling the user how to view a copy of this
+ License. (Exception: if the Program itself is interactive but
+ does not normally print such an announcement, your work based on
+ the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole. If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works. But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+ 3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+ a) Accompany it with the complete corresponding machine-readable
+ source code, which must be distributed under the terms of Sections
+ 1 and 2 above on a medium customarily used for software interchange; or,
+
+ b) Accompany it with a written offer, valid for at least three
+ years, to give any third party, for a charge no more than your
+ cost of physically performing source distribution, a complete
+ machine-readable copy of the corresponding source code, to be
+ distributed under the terms of Sections 1 and 2 above on a medium
+ customarily used for software interchange; or,
+
+ c) Accompany it with the information you received as to the offer
+ to distribute corresponding source code. (This alternative is
+ allowed only for noncommercial distribution and only if you
+ received the program in object code or executable form with such
+ an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it. For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable. However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+ 4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License. Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+ 5. You are not required to accept this License, since you have not
+signed it. However, nothing else grants you permission to modify or
+distribute the Program or its derivative works. These actions are
+prohibited by law if you do not accept this License. Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+ 6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions. You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+ 7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License. If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all. For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices. Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+ 8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded. In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+ 9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time. Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number. If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation. If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+ 10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission. For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this. Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+ NO WARRANTY
+
+ 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+ 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+ <one line to give the program's name and a brief idea of what it does.>
+ Copyright (C) <year> <name of author>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+ Gnomovision version 69, Copyright (C) year name of author
+ Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary. Here is a sample; alter the names:
+
+ Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+ `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+ <signature of Ty Coon>, 1 April 1989
+ Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs. If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.
--- /dev/null
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+#header,#content,#footnotes,#footer{max-width:none}
+#toc,.sidebarblock,.exampleblock>.content{background:none!important}
+#toc{border-bottom:1px solid #dddddf!important;padding-bottom:0!important}
+body.book #header{text-align:center}
+body.book #header>h1:first-child{border:0!important;margin:2.5em 0 1em}
+body.book #header .details{border:0!important;display:block;padding:0!important}
+body.book #header .details span:first-child{margin-left:0!important}
+body.book #header .details br{display:block}
+body.book #header .details br+span::before{content:none!important}
+body.book #toc{border:0!important;text-align:left!important;padding:0!important;margin:0!important}
+body.book #toc,body.book #preamble,body.book h1.sect0,body.book .sect1>h2{page-break-before:always}
+.listingblock code[data-lang]::before{display:block}
+#footer{padding:0 .9375em}
+.hide-on-print{display:none!important}
+.print-only{display:block!important}
+.hide-for-print{display:none!important}
+.show-for-print{display:inherit!important}}
+@media amzn-kf8,print{#header>h1:first-child{margin-top:1.25rem}
+.sect1{padding:0!important}
+.sect1+.sect1{border:0}
+#footer{background:none}
+#footer-text{color:rgba(0,0,0,.6);font-size:.9em}}
+@media amzn-kf8{#header,#content,#footnotes,#footer{padding:0}}
+</style>
+<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
+<head>
+<!-- <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=DotGothic16"> -->
+<!-- <link rel="icon" type="image/x-icon" href="https://raw.githubusercontent.com/A-Larsen/math-notes/refs/heads/main/favicon.png"> -->
+<!-- <link rel="icon" type="image/png" href="N2DE_favicon.png"/> -->
+<!-- <link rel="preconnect" href="https://fonts.googleapis.com"> -->
+<!-- <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin> -->
+<!-- <link href="https://fonts.googleapis.com/css2?family=Abril+Fatface&display=swap" rel="stylesheet"> -->
+<style>
+
+/*--------------------------------------------------------------*/
+/*use '!important' to override default css used by asciidoctor*/
+/*--------------------------------------------------------------*/
+
+:root {
+ --gruvbox-black: #282828;
+ --gruvbox-black2: #1d2021;
+ --gruvbox-black3: #463f39;
+ --gruvbox-red: #fc7869;
+ --gruvbox-yellow: #fabd2f;
+ --gruvbox-white: #ebdbb2;
+ --gruvbox-white2: #a7a187;
+ --gruvbox-blue: #83a598;
+ --gruvbox-green: #b8bb26;
+ --gruvbox-bg1: #7c6f64;
+ --gruvbox-bg2: #665c54;
+
+}
+
+.title {
+ color: var(--gruvbox-red) !important;
+}
+
+blockquote {
+ color: var(--gruvbox-white) !important;
+}
+
+table {
+ margin: 0 auto !important;
+}
+
+.hdlist1 {
+ font-size: 1.3em;
+}
+
+cite {
+ color: var(--gruvbox-green) !important;
+}
+
+.tableblock {
+ background-color: inherit;
+ color: var(--gruvbox-white);
+ max-width: 95%;
+}
+
+.tableblock th {
+ background-color: var(--gruvbox-black3);
+ color: var(--gruvbox-white);
+ max-width: 97%;
+}
+
+code:not([data-lang]) {
+ background-color: var(--gruvbox-bg2) !important;
+ color: var(--gruvbox-white);
+ text-shadow: none;
+}
+
+.checklist {
+ text-align: left;
+ font-size: .8em;
+}
+
+.checklist li ul { margin-left: 3%;
+}
+
+#content, h1, pre {
+ border-radius: 8px !important;
+}
+
+#header, #content, #footnotes, #footer {
+ padding-left: 0 !important;
+ padding-right: 0 !important;
+}
+
+.api-type a:hover {
+ text-decoration: underline;
+}
+
+.api-type, .api-type a {
+ color: var(--gruvbox-green);
+ text-decoration: none;
+}
+
+pre {
+ border-style: solid !important;
+ border-color: white !important;
+ border-width: 2px !important;
+}
+
+h1 {
+ /* font-family: "DotGothic16", sans-serif !important;*/
+
+
+ background-color: var(--gruvbox-white2) !important;
+ color: var(--gruvbox-black) !important;
+}
+
+.admonitionblock > table td.content {
+ color: var(--gruvbox-white) !important;
+}
+
+/*
+html {
+ margin: 0;
+ height: 100%;
+ width: 100%;
+}
+
+
+*/
+/*html {*/
+
+body {
+ /*background: black url("background-image-space.jpeg") no-repeat fixed center;*/
+ /*background-color: black;*/
+ background-color: var(--gruvbox-black);
+ background-attachment: fixed;
+ background-size: cover;
+ overflow-y: scroll;
+ /*
+ margin: 0;
+ height: 100%;
+ width: 100%;
+ overflow: hidden;
+ */
+}
+
+
+/*
+body {
+ overflow-y: scroll;
+ background: rgba(0,0,0,0);
+ height: 100%;
+ margin: 2%;
+}
+*/
+
+#toc {
+ background-color: var(--gruvbox-black2) !important;
+ /*opacity: .9;*/
+}
+
+#toctitle {
+ color: var(--gruvbox-yellow);
+}
+
+a {
+ color: var(--gruvbox-bg1);
+}
+
+#content {
+ color: #ebdbb2;
+ background: var(--gruvbox-black);
+ /*opacity: .9;*/
+}
+
+#header > h1:nth-last-child(2) {
+ border-bottom: none !important;
+ background-color: rgba(0, 0, 0, .1);
+ padding-left: 2%;
+}
+
+.sect1 + .sect1 {
+ border-top: none !important;
+}
+
+.sect1 h2 {
+ background-size: cover;
+ background-attachment: fixed;
+ /*
+ border-bottom: 1px solid var(--gruvbox-white);
+ border-top: 1px solid var(--gruvbox-white);
+ */
+ padding: 10px;
+ text-align: left;
+ color: var(--gruvbox-red) !important;
+ /*
+ text-shadow: 1px 1px 1px var(--gruvbox-black);
+ text-shadow: 3px 3px 3px var(--gruvbox-black);
+ text-shadow: 5px 5px 5px var(--gruvbox-blue);
+ */
+}
+
+h3, h4, h5 {
+ /*
+ text-shadow: 1px 1px 1px var(--gruvbox-white);
+ */
+}
+
+h3 {
+ color: var(--gruvbox-red) !important;
+}
+
+h4 {
+ color: var(--gruvbox-yellow) !important;
+}
+
+h5 {
+ color: #83a598 !important;
+}
+
+h2 ~ *:not(h1) {
+ margin-left: .5em;
+}
+
+.pygments {
+ max-width: 97% !important;
+ white-space: pre;
+ overflow-x: scroll !important;
+}
+
+::before {
+ /*makes sure that the programming language that show up on hover is within
+ pre tag*/
+ padding-right: 3%;
+}
+
+@media screen and (max-width: 800px) {
+ .checklist li ul {
+ margin-left: 6% !important;
+ }
+ #toc {
+ padding-left: 10px;
+ }
+
+ footer {
+ margin-bottom: 10px !important;
+ }
+ html {
+ margin-bottom: 10px !important;
+ }
+}
+@media screen and (max-width: 535px) {
+ h3 ~ *:not(h2):not(h3) {
+ margin-left: 0 !important;
+ }
+
+ h4 ~ *:not(h2):not(h3):not(.h3):not(h4) {
+ margin-left: 0 !important;
+ }
+ h5 ~ *:not(h2):not(h3):not(.h3):not(h4):not(.h4):not(h5) {
+ margin-left: 0 !important;
+ }
+
+ footer {
+ margin-bottom: 10px !important;
+ }
+ html {
+ margin-bottom: 10px !important;
+ }
+}
+h3 ~ *:not(h2):not(h3) {
+ margin-left: 1.5em;
+}
+
+h4 ~ *:not(h2):not(h3):not(.h3):not(h4) {
+ margin-left: 2em;
+}
+h5 ~ *:not(h2):not(h3):not(.h3):not(h4):not(.h4):not(h5) {
+ margin-left: 2.5em;
+}
+
+
+.sect1 h2 {
+
+ /*
+ background: linear-gradient(
+ to bottom,
+ rgba(251, 189, 47, 0.2), /* yellow */
+ rgba(0, 0, 0, 0.4) /* black */
+ );
+ */
+ /*opacity: .9;*/
+ }
+
+#preamble p{
+ padding-left: 10px;
+ color: var(--gruvbox-white) !important;
+}
+
+#footer {
+ max-width: 62.5em !important;
+ padding-left: 10px !important;
+ text-align: center;
+}
+
+.logo img {
+ display: block !important;
+ margin-left: auto !important;
+ margin-right: auto !important;
+}
+
+#header > h1:first-child {
+ margin-top: .3em !important;
+ padding-top: .2em !important;
+ text-align: center;
+}
+
+footer {
+ max-width: 62.5em;
+ margin-left: auto;
+ margin-right: auto;
+ display: block;
+
+}
+
+details[open] > summary::before {
+ /* display: none;*/
+ border-top: none;
+ content: "â–¼";
+ margin-top: -12px;
+}
+
+.example.stemblock {
+ border: solid;
+ font-size: 2vw;
+ max-width: 40%;
+ margin: auto;
+}
+
+.center {
+ max-width: 500px;
+ display: flex;
+ justify-content: center;
+}
+
+.highlight {
+ color: var(--gruvbox-yellow)
+}
+
+.border {
+ padding: 4px;
+ border: 2px solid rgba(255, 0, 0, .3);
+}
+
+.dull {
+ opacity: 40%;
+}
+
+.inline {
+ margin-right: 5%;
+ display: inline-block;
+}
+
+
+</style>
+
+</head>
+
+<script src="docinfo.js"></script>
+
+
+</head>
+<body class="article">
+<div id="header">
+<h1>Tetris</h1>
+</div>
+<div id="content">
+<div class="sect1">
+<h2 id="_installing">Installing</h2>
+<div class="sectionbody">
+<div class="listingblock">
+<div class="content">
+<pre>make</pre>
+</div>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_running">Running</h2>
+<div class="sectionbody">
+<div class="listingblock">
+<div class="content">
+<pre>./tetris</pre>
+</div>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_controls">Controls</h2>
+<div class="sectionbody">
+<table class="tableblock frame-all grid-all stretch">
+<colgroup>
+<col style="width: 50%;">
+<col style="width: 50%;">
+</colgroup>
+<thead>
+<tr>
+<th class="tableblock halign-left valign-top">action</th>
+<th class="tableblock halign-left valign-top">keyboard</th>
+</tr>
+</thead>
+<tbody>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">move right</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">d</p></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">move left</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">a</p></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">rotate piece</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">r</p></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">fast drop</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">s</p></td>
+</tr>
+</tbody>
+</table>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_dependencies">Dependencies</h2>
+<div class="sectionbody">
+<div class="ulist">
+<ul>
+<li>
+<p>lib SDL2</p>
+</li>
+<li>
+<p>lib SDL2 ttf</p>
+</li>
+</ul>
+</div>
+</div>
+</div>
+</div>
+<script type="text/x-mathjax-config">
+MathJax.Hub.Config({
+ messageStyle: "none",
+ tex2jax: {
+ inlineMath: [["\\(", "\\)"]],
+ displayMath: [["\\[", "\\]"]],
+ ignoreClass: "nostem|nolatexmath"
+ },
+ asciimath2jax: {
+ delimiters: [["\\$", "\\$"]],
+ ignoreClass: "nostem|noasciimath"
+ },
+ TeX: { equationNumbers: { autoNumber: "none" } }
+})
+MathJax.Hub.Register.StartupHook("AsciiMath Jax Ready", function () {
+ MathJax.InputJax.AsciiMath.postfilterHooks.Add(function (data, node) {
+ if ((node = data.script.parentNode) && (node = node.parentNode) && node.classList.contains("stemblock")) {
+ data.math.root.display = "block"
+ }
+ return data
+ })
+})
+</script>
+<script src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.9/MathJax.js?config=TeX-MML-AM_HTMLorMML"></script>
+</body>
+</html>
\ No newline at end of file
--- /dev/null
+/*
+ * Copyright (C) 2024 Austin Larsen
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 2 of the License, or (at your option) any later
+ * version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+#include <SDL2/SDL_error.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <assert.h>
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_ttf.h>
+#include <math.h>
+#include <time.h>
+
+#define ARENA_WIDTH_PX 400U
+#define ARENA_HEIGHT_PX 800U
+#define SCREEN_WIDTH_PX 1200U
+#define SCREEN_HEIGHT_PX 800U
+#define ARENA_PADDING_PX 400U
+#define ARENA_WIDTH 8U
+#define ARENA_HEIGHT 18U
+#define ARENA_SIZE 144U
+#define PIECE_WIDTH 4U
+#define PIECE_HEIGHT 4U
+#define PIECE_SIZE 16U
+#define TETROMINOS_DATA_SIZE 16U
+#define BLOCK_SIZE_PX 50U
+#define TETROMINOS_COUNT 7U
+#define PIECE_COLOR_SIZE 4U
+#define ARENA_PADDING_TOP 2U
+#define FONT "./fonts/NotoSansMono-Regular.ttf"
+
+#define END(check, str1, str2) \
+ if (check) { \
+ assert(check); \
+ fprintf(stderr, "%s\n%s", str1, str2); \
+ exit(1); \
+ } \
+
+enum {PIECE_I, PIECE_J, PIECE_L, PIECE_O, PIECE_S, PIECE_T, PIECE_Z,
+ PIECE_COUNT};
+
+enum {COLOR_RED, COLOR_GREEN, COLOR_BLUE, COLOR_ORANGE, COLOR_GREY,
+ COLOR_BLACK, COLOR_SIZE};
+
+enum {COLLIDE_NONE = 0, COLLIDE_LEFT = 1 << 0, COLLIDE_RIGHT = 1 << 1,
+ COLLIDE_TOP = 1 << 2, COLLIDE_BOTTOM = 1 << 3, COLLIDE_PIECE = 1 << 4};
+
+enum {UPDATE_MAIN, UPDATE_LOSE};
+
+typedef struct _Size {
+ int w;
+ int h;
+ uint8_t start_x;
+ uint8_t start_y;
+} Size;
+
+typedef struct _Game {
+ uint8_t level;
+ uint64_t score;
+ SDL_Renderer *renderer;
+ SDL_Window *window;
+ TTF_Font *lose_font;
+ TTF_Font *ui_font;
+ uint8_t placed[ARENA_SIZE]; // 8 x 18 */
+} Game;
+
+typedef uint8_t (*Update_callback)(Game *game, uint64_t frame, SDL_KeyCode key,
+ bool keydown);
+
+void
+drawText(SDL_Renderer *renderer, TTF_Font *font, const char *text,
+ SDL_Point point)
+{
+ int w = 0;
+ int h = 0;
+ int padding = 8;
+
+ TTF_SizeText(font, text, &w, &h);
+
+ SDL_Color font_color = {.r = 255, .g = 255, .b =255, .a = 255};
+ SDL_Surface *surface = TTF_RenderText_Solid(font, text, font_color);
+
+ END(surface == NULL, "Could not create text surface\n", SDL_GetError());
+
+ SDL_Rect rect = {
+ .x = point.x - (w / 2),
+ .y = point.y - (h / 2),
+ .w = w,
+ .h = h,
+ };
+
+ SDL_Rect text_background = {
+ .x = rect.x - padding,
+ .y = rect.y - padding,
+ .w = rect.w + padding * 2,
+ .h = rect.h + padding * 2
+ };
+
+ SDL_Texture *texture = SDL_CreateTextureFromSurface(renderer, surface);
+
+ END(texture == NULL, "Could not create texture", SDL_GetError());
+
+ SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
+ SDL_RenderFillRect(renderer, &text_background);
+ SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
+ SDL_RenderDrawRect(renderer, &text_background);
+ SDL_RenderCopy(renderer, texture, NULL, &rect);
+ SDL_FreeSurface(surface);
+ SDL_DestroyTexture(texture);
+}
+
+int
+findPoints(uint8_t level, uint8_t lines)
+{
+ switch (lines) {
+ case 1: return 40 * (level + 1);
+ case 2: return 100 * (level + 1);
+ case 3: return 300 * (level + 1);
+ case 4: return 1200 * (level + 1);
+ }
+
+ return 0;
+}
+
+void
+addToArena(uint8_t *placed, uint8_t i)
+{
+ // bounds checking
+ if (i < ARENA_SIZE && i >= 0) placed[i] = 1;
+}
+
+uint8_t
+getPlacedPosition(SDL_Point pos)
+{
+ uint8_t i = pos.y * ARENA_WIDTH + pos.x;
+ return i < ARENA_SIZE ? i : ARENA_SIZE - 1;
+}
+
+void
+setColor(SDL_Renderer *renderer, uint8_t color)
+{
+ const SDL_Color colors[] = {
+ [COLOR_RED] = {.r = 217, .g = 100, .b = 89, .a = 255},
+ [COLOR_GREEN] = {.r = 88, .g = 140, .b = 126, .a = 255},
+ [COLOR_BLUE] = {.r = 146, .g = 161, .b = 185, .a = 255},
+ [COLOR_ORANGE] = {.r = 242, .g = 174, .b = 114, .a = 255},
+ [COLOR_GREY] = {.r = 89, .g = 89, .b = 89, .a = 89},
+ [COLOR_BLACK] = {.r = 0, .g = 0, .b = 0, .a = 0},
+ };
+
+ SDL_SetRenderDrawColor(renderer, colors[color].r, colors[color].g,
+ colors[color].b, colors[color].a);
+}
+
+void
+getXY(uint8_t i, int *x, int *y) {
+ *x = i % PIECE_WIDTH;
+ *y = floor((float)i / PIECE_HEIGHT);
+}
+
+void
+getPieceSize(uint8_t *piece, Size *size)
+{
+ memset(size, 0, sizeof(Size));
+
+ bool foundStartx = false;
+ bool foundStarty = false;
+
+ for (uint8_t x = 0; x < PIECE_WIDTH; ++x) {
+ for (uint8_t y = 0; y < PIECE_HEIGHT; ++y) {
+ uint8_t i = y * PIECE_WIDTH + x;
+
+ if (piece[i]) {
+ if (!foundStartx) {
+ size->start_x = x;
+ foundStartx = true;
+ }
+
+ size->w++;
+ break;
+ }
+ }
+ }
+
+ for (uint8_t y = 0; y < PIECE_HEIGHT; ++y) {
+ for (uint8_t x = 0; x < PIECE_WIDTH; ++x) {
+ uint8_t i = y * PIECE_WIDTH + x;
+
+ if (piece[i]) {
+ if (!foundStarty) {
+ size->start_y = y;
+ foundStarty = true;
+ }
+
+ size->h++;
+ break;
+ }
+ }
+ }
+}
+
+void
+rotatePiece(uint8_t *piece, uint8_t *rotated)
+{
+ memset(rotated, 0, sizeof(uint8_t) * PIECE_SIZE);
+
+ uint8_t i = 0;
+
+ // 90 degrees
+ for (int x = 0; x < PIECE_HEIGHT; ++x) {
+ for (int y = PIECE_WIDTH - 1; y >= 0; --y) {
+ uint8_t j = y * PIECE_WIDTH + x;
+
+ rotated[i] = piece[j];
+ ++i;
+ }
+ }
+}
+
+void
+drawTetromino(SDL_Renderer *renderer, uint8_t piece[PIECE_SIZE],
+ SDL_Point position, uint8_t color)
+{
+ for (int i = 0; i < TETROMINOS_DATA_SIZE; ++i) {
+ if (!piece[i]) continue;
+
+ int x, y; getXY(i, &x, &y);
+
+ SDL_Rect rect = {
+ .x = ((x + position.x) * BLOCK_SIZE_PX) + ARENA_PADDING_PX,
+ .y = (y + position.y - ARENA_PADDING_TOP) * BLOCK_SIZE_PX,
+ .w = BLOCK_SIZE_PX, .h = BLOCK_SIZE_PX
+ };
+
+ setColor(renderer, color);
+ SDL_RenderFillRect(renderer, &rect);
+ SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
+ SDL_RenderDrawRect(renderer, &rect);
+ }
+}
+
+void
+printPlaced(uint8_t *placed)
+{
+ uint8_t i = 0;
+
+ for (int y = 0; y < ARENA_HEIGHT; ++y) {
+ printf("%.3d: ", y * ARENA_WIDTH);
+
+ for (int x = 0; x < ARENA_WIDTH; ++x) {
+ i = (y * ARENA_WIDTH) + x;
+
+ printf("%d", placed[i]);
+ }
+
+ printf("\n");
+ }
+}
+
+void
+clearRow(uint8_t *placed, uint8_t c)
+{
+ uint8_t temp[ARENA_SIZE];
+
+ memset(temp, 0, sizeof(uint8_t) * ARENA_SIZE);
+ memcpy(temp, placed, sizeof(uint8_t) * ARENA_SIZE);
+
+ for (int y = c; y > 0; --y) {
+ for (uint8_t x = 0; x < ARENA_WIDTH; ++x) {
+ uint8_t i = y * ARENA_WIDTH + x;
+
+ if (i >= 0) temp[i] = placed[i - ARENA_WIDTH];
+ }
+ }
+
+ memcpy(placed, temp, sizeof(uint8_t) * ARENA_SIZE);
+}
+
+uint8_t
+checkForRowClearing(uint8_t *placed)
+{
+ uint8_t row_count = 0;
+ uint8_t lines = 0;
+
+ for (uint8_t y = 0; y < ARENA_HEIGHT; ++y) {
+ for (uint8_t x = 0; x < ARENA_WIDTH; ++x) {
+ if (x == 0) row_count = 0;
+
+ uint8_t i = y * ARENA_WIDTH + x;
+
+ if (placed[i]) row_count++;
+
+ if ((x == ARENA_WIDTH - 1) && (row_count == ARENA_WIDTH)) {
+ clearRow(placed, y);
+ lines++;
+ }
+
+ }
+ }
+
+ return lines;
+}
+
+void
+addToPlaced(uint8_t *placed, uint8_t *piece, SDL_Point position)
+{
+ uint8_t pos = getPlacedPosition(position);
+
+ for (uint8_t i = 0; i < TETROMINOS_DATA_SIZE; ++i) {
+ int x, y; getXY(i, &x, &y);
+ uint8_t piece_i = y * PIECE_WIDTH + x;
+ uint8_t placed_i = y * ARENA_WIDTH + x;
+
+ if (piece[piece_i]) addToArena(placed, pos + placed_i);
+ }
+}
+
+uint8_t
+collisionCheck(uint8_t *placed, uint8_t *piece, SDL_Point position)
+{
+ Size size; getPieceSize(piece, &size);
+ uint8_t placed_pos = getPlacedPosition(position);
+ uint8_t collide = COLLIDE_NONE;
+
+ if (position.x < -size.start_x) collide |= COLLIDE_LEFT;
+
+ if (position.x + size.start_x + size.w > ARENA_WIDTH)
+ collide |= COLLIDE_RIGHT;
+
+ if (position.y + size.start_y + size.h > ARENA_HEIGHT)
+ collide |= COLLIDE_BOTTOM;
+
+ for (uint8_t y = 0; y < PIECE_HEIGHT; ++y) {
+ for (uint8_t x = 0; x < PIECE_WIDTH; ++x) {
+ uint8_t piece_i = y * PIECE_WIDTH + x;
+ uint8_t placed_i = placed_pos + (y * ARENA_WIDTH + x);
+ if (piece[piece_i] && placed[placed_i]) {
+ collide |= COLLIDE_PIECE;
+ return collide;
+ }
+ }
+ }
+
+ return collide;
+}
+
+void
+pickPiece(uint8_t *piece, uint8_t *color)
+{
+ const uint8_t tetrominos[TETROMINOS_COUNT]
+ [PIECE_SIZE] = {
+ // each piece has 4 ones
+ [PIECE_I] = {0,0,0,0,
+ 1,1,1,1,
+ 0,0,0,0,
+ 0,0,0,0},
+
+ [PIECE_J] = {0,0,0,0,
+ 1,0,0,0,
+ 1,1,1,0,
+ 0,0,0,0},
+
+ [PIECE_L] = {0,0,0,0,
+ 0,0,1,0,
+ 1,1,1,0,
+ 0,0,0,0},
+
+ [PIECE_O] = {0,0,0,0,
+ 0,1,1,0,
+ 0,1,1,0,
+ 0,0,0,0},
+
+ [PIECE_S] = {0,0,0,0,
+ 0,1,1,0,
+ 1,1,0,0,
+ 0,0,0,0},
+
+ [PIECE_T] = {0,0,0,0,
+ 0,1,0,0,
+ 1,1,1,0,
+ 0,0,0,0},
+
+ [PIECE_Z] = {0,0,0,0,
+ 1,1,0,0,
+ 0,1,1,0,
+ 0,0,0,0},
+ };
+
+ const uint8_t piece_colors[PIECE_COLOR_SIZE] = {COLOR_RED, COLOR_GREEN,
+ COLOR_BLUE, COLOR_ORANGE};
+
+ uint8_t id = (float)((float)rand() / (float)RAND_MAX) * PIECE_COUNT;
+
+ memcpy(piece, &tetrominos[id], sizeof(uint8_t) * PIECE_SIZE);
+
+ *color = piece_colors[((*color) + 1) % PIECE_COLOR_SIZE];
+}
+
+void
+Game_Init(Game *game)
+{
+ memset(game, 0, sizeof(Game));
+
+ END(SDL_Init(SDL_INIT_VIDEO) != 0, "Could not create texture",
+ SDL_GetError());
+
+ END(TTF_Init() != 0, "Could not initialize TTF", TTF_GetError());
+
+ game->lose_font = TTF_OpenFont(FONT, 50);
+
+ END(game->lose_font == NULL, "Could not open font", TTF_GetError());
+
+ game->ui_font = TTF_OpenFont(FONT, 30);
+
+ END(game->ui_font == NULL, "Could not open font", TTF_GetError());
+
+ game->window = SDL_CreateWindow("tetris", SDL_WINDOWPOS_UNDEFINED,
+ SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH_PX,
+ SCREEN_HEIGHT_PX, SDL_WINDOW_SHOWN);
+
+ END(game->window == NULL, "Could not create window", SDL_GetError());
+
+ game->renderer = SDL_CreateRenderer(game->window, 0,
+ SDL_RENDERER_SOFTWARE);
+
+ END(game->renderer == NULL, "Could not create renderer", SDL_GetError());
+}
+
+void
+drawPlaced(uint8_t *placed, SDL_Renderer *renderer) {
+ for (int x = 0; x < ARENA_WIDTH; ++x) {
+ for (int y = 0; y < ARENA_HEIGHT; ++y) {
+ uint8_t i = y * ARENA_WIDTH + x;
+
+ if (!placed[i]) continue;
+
+ SDL_Rect rect = {
+ .x = (x * BLOCK_SIZE_PX) + ARENA_PADDING_PX,
+ .y = (y - ARENA_PADDING_TOP) * BLOCK_SIZE_PX,
+ .w = BLOCK_SIZE_PX, .h = BLOCK_SIZE_PX
+ };
+
+ setColor(renderer, COLOR_GREY);
+ SDL_RenderFillRect(renderer, &rect);
+ SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
+ SDL_RenderDrawRect(renderer, &rect);
+ }
+ }
+}
+
+static uint8_t
+updateLose(Game *game, uint64_t frame, SDL_KeyCode key, bool keydown)
+{
+ SDL_Point point = {.x = ARENA_WIDTH_PX / 2 + ARENA_PADDING_PX,
+ .y = ARENA_HEIGHT_PX / 2};
+
+ drawPlaced(game->placed, game->renderer);
+ drawText(game->renderer, game->lose_font, "You Lose", point);
+ return UPDATE_LOSE;
+}
+
+static uint8_t
+updateMain(Game *game, uint64_t frame, SDL_KeyCode key, bool keydown)
+{
+ static SDL_Point piece_position = {.x = 0, .y = -1};
+ static uint8_t fall_speed = 30;
+ static uint8_t current_piece[PIECE_SIZE];
+ static uint8_t color = COLOR_RED;
+ static bool init = true;
+
+ if (init) {
+ srand(time(NULL));
+ memset(&game->placed, 0, sizeof(uint8_t) * ARENA_SIZE);
+ pickPiece(current_piece, &color);
+ init = false;
+ }
+
+ if (piece_position.y == -1) {
+ Size size;
+ getPieceSize(current_piece, &size);
+ piece_position.x = (ARENA_WIDTH / 2) - (size.w / 2);
+ }
+
+ drawTetromino(game->renderer, current_piece, piece_position, color);
+
+ if (!keydown) fall_speed = 30;
+
+ switch (key) {
+ case SDLK_d: {
+ SDL_Point check = {.x = piece_position.x + 1,
+ .y = piece_position.y};
+
+ if (!collisionCheck(game->placed, current_piece, check)) {
+ piece_position.x++;
+ }
+
+ break;
+ }
+
+ case SDLK_a: {
+ SDL_Point check = {.x = piece_position.x - 1,
+ .y = piece_position.y};
+
+ if (!collisionCheck(game->placed, current_piece, check)) {
+ piece_position.x--;
+ }
+
+ break;
+ }
+
+ case SDLK_s: {
+ fall_speed = 1;
+ break;
+ }
+
+ case SDLK_r: {
+ uint8_t rotated[PIECE_SIZE];
+ SDL_Point check;
+
+ rotatePiece(current_piece, rotated);
+
+ uint8_t collide = collisionCheck(game->placed, rotated,
+ piece_position);
+
+ memcpy(&check, &piece_position, sizeof(SDL_Point));
+
+ if (collide == COLLIDE_LEFT) {
+ while (collide == COLLIDE_LEFT) {
+ check.x++;
+ collide = collisionCheck(game->placed, rotated, check);
+ }
+
+ } else if (collide == COLLIDE_RIGHT) {
+ while (collide == COLLIDE_RIGHT) {
+ check.x--;
+ collide = collisionCheck(game->placed, rotated, check);
+ }
+ }
+
+ if (collide == COLLIDE_NONE) {
+ memcpy(&piece_position, &check, sizeof(SDL_Point));
+ memcpy(current_piece, rotated, sizeof(uint8_t) * PIECE_SIZE);
+ }
+
+ break;
+ }
+ }
+
+ if (frame % fall_speed == 0) {
+ SDL_Point check = {.x = piece_position.x,
+ .y = piece_position.y + 1};
+
+ if (!collisionCheck(game->placed, current_piece, check)) {
+ piece_position.y++;
+ } else{
+ Size size;
+
+ getPieceSize(current_piece, &size);
+
+ if (piece_position.y + size.start_y - size.h < 0) {
+ addToPlaced(game->placed, current_piece, piece_position);
+ return UPDATE_LOSE;
+ } else {
+ fall_speed = 30;
+ addToPlaced(game->placed, current_piece, piece_position);
+ pickPiece(current_piece, &color);
+ piece_position.y = -1;
+ }
+ }
+ }
+
+ uint8_t lines = checkForRowClearing(game->placed);
+ SDL_Point point = {.x = ARENA_PADDING_PX / 2, .y = 50};
+ char score_string[255];
+
+ game->score += findPoints(game->level, lines);
+
+ sprintf(score_string, "score %ld", game->score);
+ drawText(game->renderer, game->ui_font, score_string, point);
+ drawPlaced(game->placed, game->renderer);
+ return UPDATE_MAIN;
+}
+
+void
+Game_Update(Game *game, const uint8_t fps)
+{
+ uint64_t frame = 0;
+ bool quit = false;
+ bool keydown = false;
+ uint8_t update_id = 0;
+ Update_callback update;
+ float mspd = (1.0f / (float)fps) * 1000.0f;
+
+ SDL_Rect arena_background_rect = {
+ .x = ARENA_PADDING_PX,
+ .y = 0,
+ .w = ARENA_WIDTH_PX,
+ .h = ARENA_HEIGHT_PX
+ };
+
+ while (!quit) {
+ uint32_t start = SDL_GetTicks();
+
+ switch (update_id) {
+ case UPDATE_MAIN: update = updateMain; break;
+ case UPDATE_LOSE: update = updateLose; break;
+ }
+
+ setColor(game->renderer, COLOR_GREY);
+ SDL_RenderClear(game->renderer);
+ setColor(game->renderer, COLOR_BLACK);
+ SDL_RenderFillRect(game->renderer, &arena_background_rect);
+
+ SDL_Event event;
+ SDL_KeyCode key = 0;
+
+ while (SDL_PollEvent(&event)) {
+ switch (event.type) {
+ case SDL_KEYDOWN: {
+ if (event.key.repeat == 0) {
+ key = event.key.keysym.sym;
+ keydown = true;
+ }
+
+ break;
+ }
+
+ case SDL_KEYUP: keydown = false; break;
+ case SDL_QUIT: quit = true; break;
+ }
+ }
+
+ update_id = update(game, frame, key, keydown);
+
+ uint32_t end = SDL_GetTicks();
+ uint32_t elapsed_time = end - start;
+
+ if (elapsed_time < mspd) {
+ elapsed_time = mspd - elapsed_time;
+ SDL_Delay(elapsed_time);
+ }
+
+ SDL_RenderPresent(game->renderer);
+ frame++;
+ }
+}
+
+void
+Game_Quit(Game *game)
+{
+ TTF_CloseFont(game->lose_font);
+ TTF_CloseFont(game->ui_font);
+ SDL_DestroyWindow(game->window);
+ SDL_DestroyRenderer(game->renderer);
+ TTF_Quit();
+ SDL_Quit();
+}
+
+int
+main(void)
+{
+ Game game;
+ Game_Init(&game);
+ Game_Update(&game, 60);
+ Game_Quit(&game);
+ return 0;
+}
projects / tetris.git / commitdiff