custom samples tweaking

jsnes/src/sample.js

@@ -7,13 +7,13 @@ var Sample = function (audiobuffer, toneHz, gain) {
       samples[i] += channel_samples[i] + 1;
     }
   }
-  gain = (gain ? gain : 1) / (audiobuffer.numberOfChannels * 2);
   for (i = 0; i < samples.length; i ++) {
-    samples[i] = samples[i] * gain;
+    samples[i] = samples[i] / audiobuffer.numberOfChannels;
   }
-
+  this.gain = gain || 1;
   this.samples = samples;
   this.index = 0;
+  this.sampleRate = audiobuffer.sampleRate;
   this.increment = audiobuffer.sampleRate / toneHz;
   this.prevMaxTimer = null;
   this.prevTimer = 0;
@@ -27,6 +27,12 @@ Sample.prototype = {
     copy.index = 0;
     return copy;
   },
+  get frequency() {
+    return this.sampleRate / this.increment;
+  },
+  set frequency(toneHz) {
+    this.increment = this.sampleRate / toneHz;
+  },
   advance: function(clocksPerPeriod) { 
     this.clocksPerPeriod = clocksPerPeriod;
     this.index += this.increment / clocksPerPeriod; 
@@ -56,7 +62,7 @@ Sample.prototype = {
     var index = (this.index + (((this.increment / this.clocksPerPeriod) * timerIncreasing) / maxTimer)) >> 0;
     if (index < 0) index = 0;
     if (index >= this.samples.length) index = this.samples.length - 1;
-    return (this.samples[index] * volume);
+    return (this.samples[index] * volume * this.gain);
   }
 }
 

package.json

@@ -13,8 +13,8 @@
     "jsnes": "file:./jsnes"
   },
   "devDependencies": {
-    "@sveltejs/vite-plugin-svelte": "^4.0.0",
-    "svelte": "^5.1.3",
-    "vite": "^5.4.10"
+    "@sveltejs/vite-plugin-svelte": "^4.0.2",
+    "svelte": "^5.2.10",
+    "vite": "^5.4.11"
   }
 }

src/lib/SampleTweak.svelte

@@ -0,0 +1,64 @@
+<script>
+    import { untrack } from 'svelte';
+    import { loadSample, decodeSample } from './sampload.js'
+    let { opts = $bindable() } = $props();
+    let samplefile = $state();
+    let frequency = $state(880)
+    let gain = $state(1)
+
+    $effect(() => {
+        if (opts.sampleSquare1) {
+            opts.sampleSquare1.frequency = frequency;
+        }
+    });
+    $effect(() => {
+        if (opts.sampleSquare1) {
+            opts.sampleSquare1.gain = gain;
+        }
+    });
+    $inspect(frequency)
+    function setSample(sample) {
+        if (sample) {
+            frequency = sample.frequency;
+            gain = sample.gain;
+            opts = { sampleSquare1: sample, sampleSquare2: sample.clone(), sampleTriangle: sample.clone() };
+        } else {
+            opts = {};
+        }
+    }
+    async function meow() {
+        setSample(await loadSample("samples/meow1.wav", 720, 10));
+    }
+    async function yeargh() {
+        setSample(await loadSample("samples/YEARGH.WAV", 1300, 1));
+    }
+    meow();
+    $effect(() => {
+        if (samplefile && samplefile.length > 0) {
+            let reader = new FileReader();
+            reader.onload = async () => { setSample(await decodeSample(reader.result, 880, 1)); }
+            reader.readAsArrayBuffer(samplefile[0]);
+        }
+    });
+</script>
+
+<main>
+    <div>
+        <button onclick={() => { opts = {} }}>Normal</button>
+        <button onclick={meow}>Meow</button>
+        <button onclick={yeargh}>Yeargh</button>
+        <input bind:files={samplefile} type="file" />
+    </div>
+    <div>
+        <label>
+            Frequency: 
+            <input type="range" bind:value={frequency} min="220" max="2200" step="10"/> 
+            {frequency}
+        </label>
+        <label>
+            Gain:
+            <input type="range" bind:value={gain} min="0.1" max="10" step="0.1" />
+            {gain}
+        </label>
+    </div>
+</main>

src/lib/sampload.js

@@ -1,8 +1,12 @@
 import { Sample } from 'jsnes';
 
 export async function loadSample(url, toneHz, gain) {
-    const audioCtx = new AudioContext();
     const response = await fetch(url);
-    const buffer = await audioCtx.decodeAudioData(await response.arrayBuffer());
+    return await decodeSample(await response.arrayBuffer(), toneHz, gain);
+}
+
+export async function decodeSample(arraybuffer, toneHz, gain) {
+    const audioCtx = new AudioContext();
+    const buffer = await audioCtx.decodeAudioData(arraybuffer);
     return new Sample(buffer, toneHz, gain);
 }

yarn.lock

@@ -254,10 +254,10 @@
   dependencies:
     debug "^4.3.7"
 
-"@sveltejs/vite-plugin-svelte@^4.0.0":
-  version "4.0.1"
-  resolved "https://registry.yarnpkg.com/@sveltejs/vite-plugin-svelte/-/vite-plugin-svelte-4.0.1.tgz#d6a36caf09eca00249add71fde17b1d01fdd89a2"
-  integrity sha512-prXoAE/GleD2C4pKgHa9vkdjpzdYwCSw/kmjw6adIyu0vk5YKCfqIztkLg10m+kOYnzZu3bb0NaPTxlWre2a9Q==
+"@sveltejs/vite-plugin-svelte@^4.0.2":
+  version "4.0.2"
+  resolved "https://registry.yarnpkg.com/@sveltejs/vite-plugin-svelte/-/vite-plugin-svelte-4.0.2.tgz#b2106ce4e77f074f2f4542d33413bdcad3529863"
+  integrity sha512-Y9r/fWy539XlAC7+5wfNJ4zH6TygUYoQ0Eegzp0zDDqhJ54+92gOyOX1l4MO1cJSx0O+Gp13YePT5XEa3+kX0w==
   dependencies:
     "@sveltejs/vite-plugin-svelte-inspector" "^3.0.0-next.0||^3.0.0"
     debug "^4.3.7"
@@ -332,10 +332,10 @@ esbuild@^0.21.3:
     "@esbuild/win32-ia32" "0.21.5"
     "@esbuild/win32-x64" "0.21.5"
 
-esm-env@^1.0.0:
-  version "1.1.4"
-  resolved "https://registry.yarnpkg.com/esm-env/-/esm-env-1.1.4.tgz#340c78b03ee2298d31c5b9fab9793468ede828b0"
-  integrity sha512-oO82nKPHKkzIj/hbtuDYy/JHqBHFlMIW36SDiPCVsj87ntDLcWN+sJ1erdVryd4NxODacFTsdrIE3b7IamqbOg==
+esm-env@^1.2.0:
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/esm-env/-/esm-env-1.2.0.tgz#637c0586244c0eb14bfd7f5e96a6b43b9e8f5c2b"
+  integrity sha512-OhSQuHL3mUcaQHjGe8UMG8GsJIJHYYz0flR0h9fiTPNMupLMkb7TvcRD0EeJXW5a8GHBgfz08b6FDLNK7kkPQA==
 
 esrap@^1.2.2:
   version "1.2.2"
@@ -433,10 +433,10 @@ source-map-js@^1.2.1:
   resolved "https://registry.yarnpkg.com/source-map-js/-/source-map-js-1.2.1.tgz#1ce5650fddd87abc099eda37dcff024c2667ae46"
   integrity sha512-UXWMKhLOwVKb728IUtQPXxfYU+usdybtUrK/8uGE8CQMvrhOpwvzDBwj0QhSL7MQc7vIsISBG8VQ8+IDQxpfQA==
 
-svelte@^5.1.3:
-  version "5.2.2"
-  resolved "https://registry.yarnpkg.com/svelte/-/svelte-5.2.2.tgz#a9d28dd6942e59f303298902c546909161452b45"
-  integrity sha512-eHIJRcvA6iuXdRGMESTmBtWTQCcCiol4gyH9DA60ybS35W1x27cvtbndNvWDqX72blyf+AYeQ4gzZ0XGg3L8sw==
+svelte@^5.2.10:
+  version "5.2.10"
+  resolved "https://registry.yarnpkg.com/svelte/-/svelte-5.2.10.tgz#d35399550de09e86f5344fe8e221c667bbbac68e"
+  integrity sha512-ON0OyO7vOmSjTc9mLjusu3vf1I7BvjovbiRB7j84F1WZMXV6dR+Tj4btIzxQxMHfzbGskaFmRa7qjgmBSVBnhQ==
   dependencies:
     "@ampproject/remapping" "^2.3.0"
     "@jridgewell/sourcemap-codec" "^1.5.0"
@@ -445,14 +445,14 @@ svelte@^5.1.3:
     acorn-typescript "^1.4.13"
     aria-query "^5.3.1"
     axobject-query "^4.1.0"
-    esm-env "^1.0.0"
+    esm-env "^1.2.0"
     esrap "^1.2.2"
     is-reference "^3.0.3"
     locate-character "^3.0.0"
     magic-string "^0.30.11"
     zimmerframe "^1.1.2"
 
-vite@^5.4.10:
+vite@^5.4.11:
   version "5.4.11"
   resolved "https://registry.yarnpkg.com/vite/-/vite-5.4.11.tgz#3b415cd4aed781a356c1de5a9ebafb837715f6e5"
   integrity sha512-c7jFQRklXua0mTzneGW9QVyxFjUgwcihC4bXEtujIo2ouWCe1Ajt/amn2PCxYnhYfd5k09JX3SB7OYWFKYqj8Q==