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articles/simd-rect/page.mmd

@@ -37,7 +37,8 @@ pub fn RectSIMD(comptime T: type) type {
 ### Assembly ###
 This is produced by godbolt, which apparently has AVX512 extensions, so, it's extremely compact.
 
-note: SysV prelude and outro are omitted, with inlining you can expect it looking similarly.
+Note: Calling prelude and outro are omitted, with inlining you can expect it looking similarly.
+Zig calling convention is used, which is roughly equal to C's static marked procedure.
 
 For 32bit floating point:
 ```asm
@@ -148,9 +149,8 @@ For 32bit signed integers it fares amazing too:
 
 AVX512 makes it so that there's no big penalty for double precision types, which is nice.
 
-Note that permutation masks are also supplied along side code which increase binary size.
-With inlining it could be quite substantial if per object %rip relative addressing is used.
-
 ### Edits ###
 - Reordered to use packed vectors without swizzling when possible.
 - Eliminated redundant computations.
+- Calling convention notice.
+

articles/vector-pi-rotation/page.mmd

@@ -0,0 +1,141 @@
+Title:  Optimized Vector Rotation
+Brief:  Specialized rotation methods over Pi and Pi/2 in 2D and 3D.
+Date:   1699548646
+Tags:   Programming, Zig, Optimization
+CSS:    /style.css
+
+Came up with some useful optimization for 90 and 180 degree rotations while making a grid walker,
+below implementations are given, ripped straight from source, lol.
+
+Compared to generic cos/sin method of rotation it's magnitudes of times less work in many cases, especially if glibc implementation is used.
+
+Note: Given example assumes coordinate system where Y grows downwards and X to the right.
+
+## Two dimensions
+
+```zig
+pub fn rotateByHalfPiClockwise(self: Self) Self {
+    return .{ .components = .{ -self.y(), self.x() } };
+}
+
+pub fn rotateByHalfPiCounterClockwise(self: Self) Self {
+    return .{ .components = .{ self.y(), -self.x() } };
+}
+
+pub fn rotateByPi(self: Self) Self {
+    return .{ .components = .{ -self.x(), -self.y() } };
+}
+
+```
+
+## Three dimensions
+
+```zig
+pub fn rotateByHalfPiClockwiseAroundAxis(self: Self, axis: Axis3) Self {
+    return .{ .components = switch (axis) {
+        .x => .{ self.x(), -self.z(), self.y() },
+        .y => .{ -self.z(), self.y(), self.x() },
+        .z => .{ -self.y(), self.x(), self.z() },
+    } };
+}
+
+pub fn rotateByHalfPiCounterClockwiseAroundAxis(self: Self, axis: Axis3) Self {
+    return .{ .components = switch (axis) {
+        .x => .{ self.x(), self.z(), -self.y() },
+        .y => .{ self.z(), self.y(), -self.x() },
+        .z => .{ self.y(), -self.x(), self.z() },
+    } };
+}
+
+pub fn rotateByPiAroundAxis(self: Self, axis: Axis3) Self {
+    return .{ .components = switch (axis) {
+        .x => .{ self.x(), -self.x(), -self.y() },
+        .y => .{ -self.x(), self.y(), -self.z() },
+        .z => .{ -self.x(), -self.y(), self.z() },
+    } };
+}
+
+```
+
+## Generated amd64 assembly
+Note: Procedure prelude/epilogue is omitted. Zig's calling convention is used, which is roughly equivalent to C's static marked function in effect.
+
+Note: It's for vectors stored packed for use in SSE, array/separate scalar passing produces worse result, at least when not inlined.
+
+### rotateByHalfPiClockwise
+Notice how it's one instruction longer than coutner-clockwise case,
+so, choice of coordinate system effects costs of particular direction to rotate around.
+
+```asm
+        vmovlpd qword ptr [rsp], xmm0
+        vmovshdup       xmm1, xmm0
+        vpbroadcastd    xmm2, dword ptr [rip + .LCPI2_0]
+        vpxor   xmm1, xmm1, xmm2
+        vbroadcastss    xmm0, xmm0
+        vblendps        xmm0, xmm0, xmm1, 1
+```
+### rotateByHalfPiCounterClockwise
+
+```asm
+        vmovlpd qword ptr [rsp], xmm0
+        vpbroadcastd    xmm1, dword ptr [rip + .LCPI1_0]
+        vpxor   xmm1, xmm0, xmm1
+        vmovshdup       xmm0, xmm0
+        vinsertps       xmm0, xmm0, xmm1, 16
+```
+
+### rotateByPi
+```asm
+        vmovlpd qword ptr [rsp], xmm0
+        vpermilps       xmm0, xmm0, 212
+        vpbroadcastd    xmm1, dword ptr [rip + .LCPI3_0]
+        vpxor   xmm0, xmm0, xmm1
+```
+
+### rotateByHalfPiClockwiseAroundAxis (X)
+```asm
+        sub     rsp, 24
+        vmovq   qword ptr [rsp], xmm0
+        vpermilpd       xmm1, xmm0, 1
+        vmovaps xmm2, xmm1
+        vmovss  dword ptr [rsp + 8], xmm2
+        vpbroadcastd    xmm2, dword ptr [rip + .LCPI4_0]
+        vpxor   xmm1, xmm1, xmm2
+        vpermilps       xmm0, xmm0, 212
+        vinsertps       xmm0, xmm0, xmm1, 16
+        add     rsp, 24
+```
+
+### rotateByHalfPiCounterClockwiseAroundAxis (X)
+Again, one instruction shorter.
+
+```asm
+        sub     rsp, 24
+        vextractps      dword ptr [rsp + 8], xmm0, 2
+        vmovq   qword ptr [rsp], xmm0
+        vmovshdup       xmm1, xmm0
+        vpbroadcastd    xmm2, dword ptr [rip + .LCPI5_0]
+        vpxor   xmm1, xmm1, xmm2
+        vpermilps       xmm0, xmm0, 232
+        vinsertps       xmm0, xmm0, xmm1, 32
+        add     rsp, 24
+```
+
+### rotateByPiAroundAxis (X)
+Now it's more work.
+
+```asm
+        sub     rsp, 24
+        vmovq   qword ptr [rsp], xmm0
+        vpermilpd       xmm1, xmm0, 1
+        vmovaps xmm2, xmm1
+        vmovss  dword ptr [rsp + 8], xmm2
+        vmovshdup       xmm2, xmm0
+        vbroadcastss    xmm3, dword ptr [rip + .LCPI6_0]
+        vpxor   xmm2, xmm2, xmm3
+        vpxor   xmm1, xmm1, xmm3
+        vinsertps       xmm0, xmm0, xmm2, 16
+        vinsertps       xmm0, xmm0, xmm1, 32
+        add     rsp, 24
+```
+

articles/xm-tracks/page.mmd

@@ -1,11 +0,0 @@
-Title:  .xm Tracks
-Brief:  .xm track listing with playback.
-Date:   1684868476
-Tags:   Meta, Music, Js
-CSS:    /style.css
-
-Today is the day of .xm archival and in-browser playback addition.
-It's achieved with help of [jsxm](https://github.com/a1k0n/jsxm).
-It lacks support for some things though, might need to contribute to it.
-
-Could be neat to make some small program that would generate waveforms pngs next.

compile.sh

@@ -24,5 +24,3 @@ for d in ./articles/*/; do
 done
 
 ./tools/feed_generator.py ./articles/ https://mjestecko.neocities.org/ > ./html/feed.xml
-
-./tools/track_listing_generator.py html/tracks > html/tracks.html

html/style.css

@@ -1,8 +1,26 @@
+@media (prefers-color-scheme: dark) {
+  :root {
+    --bg-color: #111;
+    --fg-color: #fff;
+    --link-color: dodgerblue;
+  }
+}
+
+* {
+  color: var(--fg-color);
+  text-decoration: none;
+}
+
+a {
+  color: var(--link-color);
+}
+
 html {
      font-size: 20px;
      font-family: "Charter","Georgia",'Times New Roman',serif;
 }
  body {
+     background-color: var(--bg-color);
      line-height: 1.3;
 }
  article, .container {
@@ -29,7 +47,7 @@ html {
      margin: 0.9em 0px 0.9em;
 }
  pre, code {
-     background-color: #eeeeff;
+     background-color: var(--bg-color);
      line-height: normal;
      overflow: auto;
      font-size: 0.8em;
@@ -46,7 +64,7 @@ html {
      flex-direction: row;
      flex-wrap: nowrap;
      font-size: 0.8em;
-     background-color: #f0f0f0;
+     background-color: var(--bg-color);
      border: 1px solid #bbbbdd;
 }
  nav li:first-child {
@@ -66,10 +84,10 @@ html {
      background-color: #e0e0e0;
 }
  nav a:link {
-     color: #44d;
+     color: var(--link-color);
 }
  nav a:visited {
-     color: #44d;
+     color: var(--link-color);
 }
  nav a.here {
      background-color: #e0e0e0;

tools/main_page_generator.py

@@ -25,18 +25,23 @@ page = f"""Personal blog of one {choice(ADJECTIVES)} Veclav Talica.
 
 """
 
-# todo: Sort by date first.
+artciles = {}
 for root, dirs, _ in walk(argv[1]):
     for d in dirs:
         metadata = parse_metadata(path.abspath(root + '/' + d + "/page.mmd"))
         article = urllib.parse.quote(d)
+        artciles[article] = {
+            "metadata": metadata
+        }
+    break
+
+for title in sorted(artciles.keys(), key=lambda a: artciles[a]["metadata"].get("Date", time.gmtime(0)), reverse=True):
+    article = artciles[title]
+    metadata = article["metadata"]
     page += (
         f"""[{metadata.get("Title", "No title given! What a clusterfuck!")}](/articles/{article}.html)\n\n"""
         f""">{metadata.get("Brief", "")}\n\n"""
     )
-        if "Tags" in metadata:
-            page += f""">*{','.join(metadata["Tags"])}*\n---\n"""
-    break
 
 curtime = time.gmtime(int(time.time()))
 page += f"Last compiled: *{MONTHS[curtime.tm_mon]} {curtime.tm_mday}, {curtime.tm_year} {curtime.tm_hour}:{curtime.tm_min:02d} UTC*\n\n"

tools/page_shares.py

@@ -2,23 +2,21 @@
 HEAD_EMBED = """
 
 <div class="container">
-<header>
-<nav>
-<strong>mjestečko</strong> /
-<a href="/">main</a> /
-<a href="https://git.poto.cafe/veclavtalica/mjestecko">source</a> /
-<a href="/tracks.html">tracks</a> /
-<a href="/feed.xml">rss</a> /
-<a href="/articles/mjestečko.html">about</a>
+<nav class="custom-nav">
+<ul>
+<li><a href="/"><strong>mjestečko</strong></a></li>
+<li><a href="https://git.poto.cafe/veclavtalica/mjestecko">source</a></li>
+<li><a href="/feed.xml">rss</a></li>
+<li><a href="/articles/mjestečko.html">about</a></li>
 </ul>
 </nav>
-</header>
 
 """
 
 NOTICE = """
----
-*Remember, - all you see here is free for use for any purpose benefiting the humanity as a whole.*
+<footer>
+<a href="#top">Take me home ↑</a>
+</footer>
 
 """
 
@@ -55,5 +53,11 @@ WEEKDAYS = {
     6: "Sunday"
 }
 
+def mixin_tag(content: str, tag: str) -> str:
+    return f"""<{tag}>
+{content}</{tag}>
+
+"""
+
 def wrap_page(page: str) -> str:
-    return HEAD_EMBED + page + NOTICE + TAIL_EMBED
+    return HEAD_EMBED + mixin_tag(page, "main") + NOTICE + TAIL_EMBED

tools/track_listing_generator.py

@@ -1,92 +0,0 @@
-#!/usr/bin/python3
-
-from sys import argv, exit
-from os import walk, path
-
-from page_shares import HEAD_EMBED, TAIL_EMBED
-
-if len(argv) <= 1:
-    print("No directory was supplied")
-    exit(-1)
-
-page = """<!DOCTYPE html>
-<html xmlns="http://www.w3.org/1999/xhtml" lang="en">
-<head>
-    <meta charset="utf-8"/>
-    <title>Tracks</title>
-    <link type="text/css" rel="stylesheet" href="/style.css"/>
-    <script type="text/javascript" src="/xm.js"></script>
-    <script type="text/javascript">
-        (function (window, document) {
-            if (!window.XMPlayer)
-                window.XMPlayer = {};
-
-            var XMPlayer = window.XMPlayer;
-            var was_init = false
-
-            // https://stackoverflow.com/questions/16245767/creating-a-blob-from-a-base64-string-in-javascript
-            function b64toBlob(base64) {
-                const decoded = atob(base64);
-                const uInt8Array = new Uint8Array(decoded.length);
-                for (let i = 0; i < decoded.length; ++i)
-                    uInt8Array[i] = decoded.charCodeAt(i);
-                return new Blob([uInt8Array]);
-            }
-
-            async function decompressGzippedBase64(str) {
-                const ds = new DecompressionStream(`gzip`);
-                const decompressedStream = b64toBlob(str).stream().pipeThrough(ds);
-                return new Response(decompressedStream).blob();
-            }
-
-            window.loadAndPlayTrack = function(url) {
-                if (!was_init) {
-                    XMPlayer.init();
-                    was_init = true;
-                }
-                var request = new XMLHttpRequest();
-                request.responseType = `text`;
-                request.open('GET', url);
-                request.send();
-                request.onload = async(_) => {
-                    if (request.readyState === 4 && request.status === 200) {
-                        XMPlayer.stop();
-                        XMPlayer.load(await (await decompressGzippedBase64(request.response)).arrayBuffer());
-                        XMPlayer.play();
-                    }
-                }
-            }
-        })(window, document)
-    </script>
-</head>
-<body>
-"""
-page += HEAD_EMBED
-
-page += """
-        <h3 id="articles">Tracks</h3>
-        <p>.xm module tracks of my own. Btw, they're playable in browser :3</p>
-        <p>Note that some files are rendered incorrectly.</p>
-        <hr/>
-"""
-
-for _, _, files in walk(argv[1]):
-    files.sort()
-    for f in files:
-        # note: Base64 gzip encoded data is expected.
-        if not f.endswith('.xm.txt'):
-            continue
-        page += (
-            f"""        <div><p style="display: inline;">{f[:-4]}</p><button style="float: right;" onclick="window.loadAndPlayTrack('/tracks/{f}')">play</button></div>\n"""
-               "        <hr/>\n"
-        )
-    break
-
-page += TAIL_EMBED
-
-page += """</div>
-</body>
-</html>
-"""
-
-print(page)