better smallmode documentation

smallmode

@@ -1,27 +0,0 @@
-// true/false
-
-mode & 0x80: statement/expression
-mode & 0x40: function/number
-mode & 0x20: sec/sample
-mode & 0x10: clip/wrap
-
-num = mode & 0x0f
-if (num < 11) {
-	// integer
-
-	2**(num >> 1) bit depth output
-	mode & 1: unsigned/signed
-} else {
-	// float
-	// 5 states (11 <= num < 16)
-	if (num == 11) {
-		// unused, feel free to use (mode & 0xf0) for whatever
-	} else if (num) {
-		byte & 2: (currently unused, normal is 0. maybe float32/float64?)
-		byte & 1: unsigned/signed (min = -1.0 or min = 0)
-	} else {
-		// unused, feel free to use (mode & 0xf0) for whatever
-	}	
-}
-
-total 8 bits!

smallmode.md

@@ -0,0 +1,36 @@
+smallmode is a method to store a bytebeat "mode" (bytebeat, floatbeat, funcbeat) in a single byte.
+the tiny data is great for encoding into a small url or file.
+it allows a ton of things and has plenty of unused areas in case you want to add more features.
+
+no player has all of these features yet but i considered everything that seemed reasonable to implement.
+i will not change anything already defined in the format because i already made my urls and backwards compatibility should stay forever.
+
+some pseudo javascript to show how the format works:
+```js
+mode & 0x80 ? /* code is statements */ : /* code is an expression */
+mode & 0x40 ? /* returns a function */ : /* returns a number */
+mode & 0x20 ? /* time as seconds */ : /* time as sample number */
+mode & 0x10 ? /* clip out of range samples */ : /* wrap out of range samples */
+
+const num = mode & 0x0f;
+if (!num) {
+	// unused, would be 1 bit signed but that's a pretty stupid mode
+	// 0x00 is an invalid mode and will NEVER be standardized
+	// if you want an unusual custom mode, i highly suggest using 0x00 and putting some extra data after it
+} else if (num < 11) {
+	// integer
+
+	2**(num >> 1) // bit depth of output
+	mode & 0x01 ? /* unsigned output */ : /* signed output */
+	// when unsigned, the output is in the range [0, 2**2**(num >> 1))
+	// when signed, the output is in the range [-(2**2**(num >> 1)), 2**2**(num >> 1) / 2)
+} else if (num === 11) {
+	// unused, would be 32 bit unsigned but javascript doesn't support that for normal numbers
+} else if (num < 13) {
+	// float
+
+	mode & 0x01 ? /* from 0.0 to 1.0 */ : /* from -1.0 to 1.0 */
+} else {
+	// unused
+}
+```

src/url/mod.ts

@@ -2,7 +2,7 @@ import { deflateSync, inflateSync } from "fflate";
 import { from89 } from "./base89.ts";
 import type { Song, SongMode } from "../common.ts";
 
-// see smallmode text file
+// see smallmode.md
 const smallmode_table = {
 	Bytebeat: 0b00000111,
 	"Signed Bytebeat": 0b00000110,