- Go+Wasm image dithering tool
- Featuring the Nord Color Palette
-
- Load an image, click Go and wait (potentially for a while) for the image
- to be dithered using the Nord color palette and the Floyd-Steinberg
- algorithm.
-
-
- Running in the browser with Wasm causes a bit of a performance penalty.
- Multithreading is not available (not that it matters much since
- Floyd-Steinberg is single-threaded), and sending data back and forth
- between JS and Wasm can take a little while.
-
-
- I've re-used code from
- this article
- to make the Wasm code run in a web worker, with some adaptations for Go
- oddities.
-
-
- If you're into that sort of thing, source code is available on
- GitHub .
-
-
-
-
-
-
-
-
-
diff --git a/dist/main.js b/dist/main.js
deleted file mode 100644
index 138ee15..0000000
--- a/dist/main.js
+++ /dev/null
@@ -1,94 +0,0 @@
-const fileInput = document.getElementById("source-image");
-const btn = document.getElementById("go-btn");
-const output = document.getElementById("output");
-const outputWrapper = document.getElementById("output-wrapper");
-
-function wasmWorker(modulePath) {
- // Create an object to later interact with
- const proxy = {};
-
- // Keep track of the messages being sent
- // so we can resolve them correctly
- let id = 0;
- let idPromises = {};
-
- return new Promise((resolve, reject) => {
- const worker = new Worker("worker.js");
- worker.postMessage({ eventType: "INITIALISE", eventData: modulePath });
- worker.addEventListener("message", function (event) {
- const { eventType, eventData, eventId } = event.data;
-
- if (eventType === "INITIALISED") {
- const methods = event.data.eventData;
- methods.forEach((method) => {
- proxy[method] = function () {
- return new Promise((resolve, reject) => {
- worker.postMessage({
- eventType: "CALL",
- eventData: {
- method: method,
- arguments: Array.from(arguments), // arguments is not an array
- },
- eventId: id,
- });
-
- idPromises[id] = { resolve, reject };
- id++;
- });
- };
- });
- resolve(proxy);
- return;
- } else if (eventType === "RESULT") {
- if (eventId !== undefined && idPromises[eventId]) {
- idPromises[eventId].resolve(eventData);
- delete idPromises[eventId];
- }
- } else if (eventType === "ERROR") {
- if (eventId !== undefined && idPromises[eventId]) {
- idPromises[eventId].reject(event.data.eventData);
- delete idPromises[eventId];
- }
- }
- });
-
- worker.addEventListener("error", function (error) {
- reject(error);
- });
- });
-}
-
-let workerResolve;
-const wasmReady = new Promise((resolve) => {
- workerResolve = resolve;
-});
-
-let workerProxy;
-wasmWorker("./main.wasm").then((w) => {
- workerProxy = w;
- workerResolve();
- btn.removeAttribute("disabled");
-});
-
-btn.addEventListener("click", async () => {
- // Clear image
- output.src = "";
-
- // Check if a file was selected
- if (fileInput.files.length === 0) {
- alert("No file selected");
- return;
- }
- const reader = new FileReader();
- reader.readAsArrayBuffer(fileInput.files[0]);
- reader.onloadend = async (evt) => {
- if (evt.target.readyState === FileReader.DONE) {
- const imageData = new Uint8Array(evt.target.result);
- const ditheredImage = await workerProxy.DitherNord(imageData);
-
- const outputValue = `data:image/png;base64,${ditheredImage}`;
- output.src = outputValue;
- outputWrapper.href = outputValue;
- }
- };
-});
diff --git a/dist/main.wasm b/dist/main.wasm
deleted file mode 100755
index dd5d917..0000000
Binary files a/dist/main.wasm and /dev/null differ
diff --git a/dist/wasm_exec.js b/dist/wasm_exec.js
deleted file mode 100644
index 5651141..0000000
--- a/dist/wasm_exec.js
+++ /dev/null
@@ -1,636 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-(() => {
- // Map multiple JavaScript environments to a single common API,
- // preferring web standards over Node.js API.
- //
- // Environments considered:
- // - Browsers
- // - Node.js
- // - Electron
- // - Parcel
- // - Webpack
-
- if (typeof global !== "undefined") {
- // global already exists
- } else if (typeof window !== "undefined") {
- window.global = window;
- } else if (typeof self !== "undefined") {
- self.global = self;
- } else {
- throw new Error("cannot export Go (neither global, window nor self is defined)");
- }
-
- if (!global.require && typeof require !== "undefined") {
- global.require = require;
- }
-
- if (!global.fs && global.require) {
- const fs = require("fs");
- if (typeof fs === "object" && fs !== null && Object.keys(fs).length !== 0) {
- global.fs = fs;
- }
- }
-
- const enosys = () => {
- const err = new Error("not implemented");
- err.code = "ENOSYS";
- return err;
- };
-
- if (!global.fs) {
- let outputBuf = "";
- global.fs = {
- constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1 }, // unused
- writeSync(fd, buf) {
- outputBuf += decoder.decode(buf);
- const nl = outputBuf.lastIndexOf("\n");
- if (nl != -1) {
- console.log(outputBuf.substr(0, nl));
- outputBuf = outputBuf.substr(nl + 1);
- }
- return buf.length;
- },
- write(fd, buf, offset, length, position, callback) {
- if (offset !== 0 || length !== buf.length || position !== null) {
- callback(enosys());
- return;
- }
- const n = this.writeSync(fd, buf);
- callback(null, n);
- },
- chmod(path, mode, callback) { callback(enosys()); },
- chown(path, uid, gid, callback) { callback(enosys()); },
- close(fd, callback) { callback(enosys()); },
- fchmod(fd, mode, callback) { callback(enosys()); },
- fchown(fd, uid, gid, callback) { callback(enosys()); },
- fstat(fd, callback) { callback(enosys()); },
- fsync(fd, callback) { callback(null); },
- ftruncate(fd, length, callback) { callback(enosys()); },
- lchown(path, uid, gid, callback) { callback(enosys()); },
- link(path, link, callback) { callback(enosys()); },
- lstat(path, callback) { callback(enosys()); },
- mkdir(path, perm, callback) { callback(enosys()); },
- open(path, flags, mode, callback) { callback(enosys()); },
- read(fd, buffer, offset, length, position, callback) { callback(enosys()); },
- readdir(path, callback) { callback(enosys()); },
- readlink(path, callback) { callback(enosys()); },
- rename(from, to, callback) { callback(enosys()); },
- rmdir(path, callback) { callback(enosys()); },
- stat(path, callback) { callback(enosys()); },
- symlink(path, link, callback) { callback(enosys()); },
- truncate(path, length, callback) { callback(enosys()); },
- unlink(path, callback) { callback(enosys()); },
- utimes(path, atime, mtime, callback) { callback(enosys()); },
- };
- }
-
- if (!global.process) {
- global.process = {
- getuid() { return -1; },
- getgid() { return -1; },
- geteuid() { return -1; },
- getegid() { return -1; },
- getgroups() { throw enosys(); },
- pid: -1,
- ppid: -1,
- umask() { throw enosys(); },
- cwd() { throw enosys(); },
- chdir() { throw enosys(); },
- }
- }
-
- if (!global.crypto && global.require) {
- const nodeCrypto = require("crypto");
- global.crypto = {
- getRandomValues(b) {
- nodeCrypto.randomFillSync(b);
- },
- };
- }
- if (!global.crypto) {
- throw new Error("global.crypto is not available, polyfill required (getRandomValues only)");
- }
-
- if (!global.performance) {
- global.performance = {
- now() {
- const [sec, nsec] = process.hrtime();
- return sec * 1000 + nsec / 1000000;
- },
- };
- }
-
- if (!global.TextEncoder && global.require) {
- global.TextEncoder = require("util").TextEncoder;
- }
- if (!global.TextEncoder) {
- throw new Error("global.TextEncoder is not available, polyfill required");
- }
-
- if (!global.TextDecoder && global.require) {
- global.TextDecoder = require("util").TextDecoder;
- }
- if (!global.TextDecoder) {
- throw new Error("global.TextDecoder is not available, polyfill required");
- }
-
- // End of polyfills for common API.
-
- const encoder = new TextEncoder("utf-8");
- const decoder = new TextDecoder("utf-8");
-
- global.Go = class {
- constructor() {
- this.argv = ["js"];
- this.env = {};
- this.exit = (code) => {
- if (code !== 0) {
- console.warn("exit code:", code);
- }
- };
- this._exitPromise = new Promise((resolve) => {
- this._resolveExitPromise = resolve;
- });
- this._pendingEvent = null;
- this._scheduledTimeouts = new Map();
- this._nextCallbackTimeoutID = 1;
-
- const setInt64 = (addr, v) => {
- this.mem.setUint32(addr + 0, v, true);
- this.mem.setUint32(addr + 4, Math.floor(v / 4294967296), true);
- }
-
- const getInt64 = (addr) => {
- const low = this.mem.getUint32(addr + 0, true);
- const high = this.mem.getInt32(addr + 4, true);
- return low + high * 4294967296;
- }
-
- const loadValue = (addr) => {
- const f = this.mem.getFloat64(addr, true);
- if (f === 0) {
- return undefined;
- }
- if (!isNaN(f)) {
- return f;
- }
-
- const id = this.mem.getUint32(addr, true);
- return this._values[id];
- }
-
- const storeValue = (addr, v) => {
- const nanHead = 0x7FF80000;
-
- if (typeof v === "number" && v !== 0) {
- if (isNaN(v)) {
- this.mem.setUint32(addr + 4, nanHead, true);
- this.mem.setUint32(addr, 0, true);
- return;
- }
- this.mem.setFloat64(addr, v, true);
- return;
- }
-
- if (v === undefined) {
- this.mem.setFloat64(addr, 0, true);
- return;
- }
-
- let id = this._ids.get(v);
- if (id === undefined) {
- id = this._idPool.pop();
- if (id === undefined) {
- id = this._values.length;
- }
- this._values[id] = v;
- this._goRefCounts[id] = 0;
- this._ids.set(v, id);
- }
- this._goRefCounts[id]++;
- let typeFlag = 0;
- switch (typeof v) {
- case "object":
- if (v !== null) {
- typeFlag = 1;
- }
- break;
- case "string":
- typeFlag = 2;
- break;
- case "symbol":
- typeFlag = 3;
- break;
- case "function":
- typeFlag = 4;
- break;
- }
- this.mem.setUint32(addr + 4, nanHead | typeFlag, true);
- this.mem.setUint32(addr, id, true);
- }
-
- const loadSlice = (addr) => {
- const array = getInt64(addr + 0);
- const len = getInt64(addr + 8);
- return new Uint8Array(this._inst.exports.mem.buffer, array, len);
- }
-
- const loadSliceOfValues = (addr) => {
- const array = getInt64(addr + 0);
- const len = getInt64(addr + 8);
- const a = new Array(len);
- for (let i = 0; i < len; i++) {
- a[i] = loadValue(array + i * 8);
- }
- return a;
- }
-
- const loadString = (addr) => {
- const saddr = getInt64(addr + 0);
- const len = getInt64(addr + 8);
- return decoder.decode(new DataView(this._inst.exports.mem.buffer, saddr, len));
- }
-
- const timeOrigin = Date.now() - performance.now();
- this.importObject = {
- go: {
- // Go's SP does not change as long as no Go code is running. Some operations (e.g. calls, getters and setters)
- // may synchronously trigger a Go event handler. This makes Go code get executed in the middle of the imported
- // function. A goroutine can switch to a new stack if the current stack is too small (see morestack function).
- // This changes the SP, thus we have to update the SP used by the imported function.
-
- // func wasmExit(code int32)
- "runtime.wasmExit": (sp) => {
- sp >>>= 0;
- const code = this.mem.getInt32(sp + 8, true);
- this.exited = true;
- delete this._inst;
- delete this._values;
- delete this._goRefCounts;
- delete this._ids;
- delete this._idPool;
- this.exit(code);
- },
-
- // func wasmWrite(fd uintptr, p unsafe.Pointer, n int32)
- "runtime.wasmWrite": (sp) => {
- sp >>>= 0;
- const fd = getInt64(sp + 8);
- const p = getInt64(sp + 16);
- const n = this.mem.getInt32(sp + 24, true);
- fs.writeSync(fd, new Uint8Array(this._inst.exports.mem.buffer, p, n));
- },
-
- // func resetMemoryDataView()
- "runtime.resetMemoryDataView": (sp) => {
- sp >>>= 0;
- this.mem = new DataView(this._inst.exports.mem.buffer);
- },
-
- // func nanotime1() int64
- "runtime.nanotime1": (sp) => {
- sp >>>= 0;
- setInt64(sp + 8, (timeOrigin + performance.now()) * 1000000);
- },
-
- // func walltime() (sec int64, nsec int32)
- "runtime.walltime": (sp) => {
- sp >>>= 0;
- const msec = (new Date).getTime();
- setInt64(sp + 8, msec / 1000);
- this.mem.setInt32(sp + 16, (msec % 1000) * 1000000, true);
- },
-
- // func scheduleTimeoutEvent(delay int64) int32
- "runtime.scheduleTimeoutEvent": (sp) => {
- sp >>>= 0;
- const id = this._nextCallbackTimeoutID;
- this._nextCallbackTimeoutID++;
- this._scheduledTimeouts.set(id, setTimeout(
- () => {
- this._resume();
- while (this._scheduledTimeouts.has(id)) {
- // for some reason Go failed to register the timeout event, log and try again
- // (temporary workaround for https://github.com/golang/go/issues/28975)
- console.warn("scheduleTimeoutEvent: missed timeout event");
- this._resume();
- }
- },
- getInt64(sp + 8) + 1, // setTimeout has been seen to fire up to 1 millisecond early
- ));
- this.mem.setInt32(sp + 16, id, true);
- },
-
- // func clearTimeoutEvent(id int32)
- "runtime.clearTimeoutEvent": (sp) => {
- sp >>>= 0;
- const id = this.mem.getInt32(sp + 8, true);
- clearTimeout(this._scheduledTimeouts.get(id));
- this._scheduledTimeouts.delete(id);
- },
-
- // func getRandomData(r []byte)
- "runtime.getRandomData": (sp) => {
- sp >>>= 0;
- crypto.getRandomValues(loadSlice(sp + 8));
- },
-
- // func finalizeRef(v ref)
- "syscall/js.finalizeRef": (sp) => {
- sp >>>= 0;
- const id = this.mem.getUint32(sp + 8, true);
- this._goRefCounts[id]--;
- if (this._goRefCounts[id] === 0) {
- const v = this._values[id];
- this._values[id] = null;
- this._ids.delete(v);
- this._idPool.push(id);
- }
- },
-
- // func stringVal(value string) ref
- "syscall/js.stringVal": (sp) => {
- sp >>>= 0;
- storeValue(sp + 24, loadString(sp + 8));
- },
-
- // func valueGet(v ref, p string) ref
- "syscall/js.valueGet": (sp) => {
- sp >>>= 0;
- const result = Reflect.get(loadValue(sp + 8), loadString(sp + 16));
- sp = this._inst.exports.getsp() >>> 0; // see comment above
- storeValue(sp + 32, result);
- },
-
- // func valueSet(v ref, p string, x ref)
- "syscall/js.valueSet": (sp) => {
- sp >>>= 0;
- Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32));
- },
-
- // func valueDelete(v ref, p string)
- "syscall/js.valueDelete": (sp) => {
- sp >>>= 0;
- Reflect.deleteProperty(loadValue(sp + 8), loadString(sp + 16));
- },
-
- // func valueIndex(v ref, i int) ref
- "syscall/js.valueIndex": (sp) => {
- sp >>>= 0;
- storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16)));
- },
-
- // valueSetIndex(v ref, i int, x ref)
- "syscall/js.valueSetIndex": (sp) => {
- sp >>>= 0;
- Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24));
- },
-
- // func valueCall(v ref, m string, args []ref) (ref, bool)
- "syscall/js.valueCall": (sp) => {
- sp >>>= 0;
- try {
- const v = loadValue(sp + 8);
- const m = Reflect.get(v, loadString(sp + 16));
- const args = loadSliceOfValues(sp + 32);
- const result = Reflect.apply(m, v, args);
- sp = this._inst.exports.getsp() >>> 0; // see comment above
- storeValue(sp + 56, result);
- this.mem.setUint8(sp + 64, 1);
- } catch (err) {
- sp = this._inst.exports.getsp() >>> 0; // see comment above
- storeValue(sp + 56, err);
- this.mem.setUint8(sp + 64, 0);
- }
- },
-
- // func valueInvoke(v ref, args []ref) (ref, bool)
- "syscall/js.valueInvoke": (sp) => {
- sp >>>= 0;
- try {
- const v = loadValue(sp + 8);
- const args = loadSliceOfValues(sp + 16);
- const result = Reflect.apply(v, undefined, args);
- sp = this._inst.exports.getsp() >>> 0; // see comment above
- storeValue(sp + 40, result);
- this.mem.setUint8(sp + 48, 1);
- } catch (err) {
- sp = this._inst.exports.getsp() >>> 0; // see comment above
- storeValue(sp + 40, err);
- this.mem.setUint8(sp + 48, 0);
- }
- },
-
- // func valueNew(v ref, args []ref) (ref, bool)
- "syscall/js.valueNew": (sp) => {
- sp >>>= 0;
- try {
- const v = loadValue(sp + 8);
- const args = loadSliceOfValues(sp + 16);
- const result = Reflect.construct(v, args);
- sp = this._inst.exports.getsp() >>> 0; // see comment above
- storeValue(sp + 40, result);
- this.mem.setUint8(sp + 48, 1);
- } catch (err) {
- sp = this._inst.exports.getsp() >>> 0; // see comment above
- storeValue(sp + 40, err);
- this.mem.setUint8(sp + 48, 0);
- }
- },
-
- // func valueLength(v ref) int
- "syscall/js.valueLength": (sp) => {
- sp >>>= 0;
- setInt64(sp + 16, parseInt(loadValue(sp + 8).length));
- },
-
- // valuePrepareString(v ref) (ref, int)
- "syscall/js.valuePrepareString": (sp) => {
- sp >>>= 0;
- const str = encoder.encode(String(loadValue(sp + 8)));
- storeValue(sp + 16, str);
- setInt64(sp + 24, str.length);
- },
-
- // valueLoadString(v ref, b []byte)
- "syscall/js.valueLoadString": (sp) => {
- sp >>>= 0;
- const str = loadValue(sp + 8);
- loadSlice(sp + 16).set(str);
- },
-
- // func valueInstanceOf(v ref, t ref) bool
- "syscall/js.valueInstanceOf": (sp) => {
- sp >>>= 0;
- this.mem.setUint8(sp + 24, (loadValue(sp + 8) instanceof loadValue(sp + 16)) ? 1 : 0);
- },
-
- // func copyBytesToGo(dst []byte, src ref) (int, bool)
- "syscall/js.copyBytesToGo": (sp) => {
- sp >>>= 0;
- const dst = loadSlice(sp + 8);
- const src = loadValue(sp + 32);
- if (!(src instanceof Uint8Array || src instanceof Uint8ClampedArray)) {
- this.mem.setUint8(sp + 48, 0);
- return;
- }
- const toCopy = src.subarray(0, dst.length);
- dst.set(toCopy);
- setInt64(sp + 40, toCopy.length);
- this.mem.setUint8(sp + 48, 1);
- },
-
- // func copyBytesToJS(dst ref, src []byte) (int, bool)
- "syscall/js.copyBytesToJS": (sp) => {
- sp >>>= 0;
- const dst = loadValue(sp + 8);
- const src = loadSlice(sp + 16);
- if (!(dst instanceof Uint8Array || dst instanceof Uint8ClampedArray)) {
- this.mem.setUint8(sp + 48, 0);
- return;
- }
- const toCopy = src.subarray(0, dst.length);
- dst.set(toCopy);
- setInt64(sp + 40, toCopy.length);
- this.mem.setUint8(sp + 48, 1);
- },
-
- "debug": (value) => {
- console.log(value);
- },
- }
- };
- }
-
- async run(instance) {
- if (!(instance instanceof WebAssembly.Instance)) {
- throw new Error("Go.run: WebAssembly.Instance expected");
- }
- this._inst = instance;
- this.mem = new DataView(this._inst.exports.mem.buffer);
- this._values = [ // JS values that Go currently has references to, indexed by reference id
- NaN,
- 0,
- null,
- true,
- false,
- global,
- this,
- ];
- this._goRefCounts = new Array(this._values.length).fill(Infinity); // number of references that Go has to a JS value, indexed by reference id
- this._ids = new Map([ // mapping from JS values to reference ids
- [0, 1],
- [null, 2],
- [true, 3],
- [false, 4],
- [global, 5],
- [this, 6],
- ]);
- this._idPool = []; // unused ids that have been garbage collected
- this.exited = false; // whether the Go program has exited
-
- // Pass command line arguments and environment variables to WebAssembly by writing them to the linear memory.
- let offset = 4096;
-
- const strPtr = (str) => {
- const ptr = offset;
- const bytes = encoder.encode(str + "\0");
- new Uint8Array(this.mem.buffer, offset, bytes.length).set(bytes);
- offset += bytes.length;
- if (offset % 8 !== 0) {
- offset += 8 - (offset % 8);
- }
- return ptr;
- };
-
- const argc = this.argv.length;
-
- const argvPtrs = [];
- this.argv.forEach((arg) => {
- argvPtrs.push(strPtr(arg));
- });
- argvPtrs.push(0);
-
- const keys = Object.keys(this.env).sort();
- keys.forEach((key) => {
- argvPtrs.push(strPtr(`${key}=${this.env[key]}`));
- });
- argvPtrs.push(0);
-
- const argv = offset;
- argvPtrs.forEach((ptr) => {
- this.mem.setUint32(offset, ptr, true);
- this.mem.setUint32(offset + 4, 0, true);
- offset += 8;
- });
-
- // The linker guarantees global data starts from at least wasmMinDataAddr.
- // Keep in sync with cmd/link/internal/ld/data.go:wasmMinDataAddr.
- const wasmMinDataAddr = 4096 + 8192;
- if (offset >= wasmMinDataAddr) {
- throw new Error("total length of command line and environment variables exceeds limit");
- }
-
- this._inst.exports.run(argc, argv);
- if (this.exited) {
- this._resolveExitPromise();
- }
- await this._exitPromise;
- }
-
- _resume() {
- if (this.exited) {
- throw new Error("Go program has already exited");
- }
- this._inst.exports.resume();
- if (this.exited) {
- this._resolveExitPromise();
- }
- }
-
- _makeFuncWrapper(id) {
- const go = this;
- return function () {
- const event = { id: id, this: this, args: arguments };
- go._pendingEvent = event;
- go._resume();
- return event.result;
- };
- }
- }
-
- if (
- typeof module !== "undefined" &&
- global.require &&
- global.require.main === module &&
- global.process &&
- global.process.versions &&
- !global.process.versions.electron
- ) {
- if (process.argv.length < 3) {
- console.error("usage: go_js_wasm_exec [wasm binary] [arguments]");
- process.exit(1);
- }
-
- const go = new Go();
- go.argv = process.argv.slice(2);
- go.env = Object.assign({ TMPDIR: require("os").tmpdir() }, process.env);
- go.exit = process.exit;
- WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => {
- process.on("exit", (code) => { // Node.js exits if no event handler is pending
- if (code === 0 && !go.exited) {
- // deadlock, make Go print error and stack traces
- go._pendingEvent = { id: 0 };
- go._resume();
- }
- });
- return go.run(result.instance);
- }).catch((err) => {
- console.error(err);
- process.exit(1);
- });
- }
-})();
diff --git a/go.mod b/go.mod
deleted file mode 100644
index 4e27449..0000000
--- a/go.mod
+++ /dev/null
@@ -1,5 +0,0 @@
-module github.com/CrispyBaguette/wasm-palette-converter
-
-go 1.17
-
-require github.com/makeworld-the-better-one/dither/v2 v2.2.0 // indirect
diff --git a/src/.gitignore b/src/.gitignore
new file mode 100644
index 0000000..66fd13c
--- /dev/null
+++ b/src/.gitignore
@@ -0,0 +1,15 @@
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
diff --git a/.vscode/settings.json b/src/.vscode/settings.json
similarity index 100%
rename from .vscode/settings.json
rename to src/.vscode/settings.json
diff --git a/src/go.mod b/src/go.mod
new file mode 100644
index 0000000..eb649b3
--- /dev/null
+++ b/src/go.mod
@@ -0,0 +1,5 @@
+module github.com/CrispyBaguette/wasm-palette-converter
+
+go 1.17
+
+require github.com/makeworld-the-better-one/dither/v2 v2.2.0
diff --git a/go.sum b/src/go.sum
similarity index 69%
rename from go.sum
rename to src/go.sum
index 34f6d30..2702960 100644
--- a/go.sum
+++ b/src/go.sum
@@ -1,8 +1,12 @@
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/makeworld-the-better-one/dither/v2 v2.2.0 h1:VTMAiyyO1YIO07fZwuLNZZasJgKUmvsIA48ze3ALHPQ=
github.com/makeworld-the-better-one/dither/v2 v2.2.0/go.mod h1:VBtN8DXO7SNtyGmLiGA7IsFeKrBkQPze1/iAeM95arc=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/main.go b/src/main.go
similarity index 62%
rename from main.go
rename to src/main.go
index aecd575..9a1e180 100644
--- a/main.go
+++ b/src/main.go
@@ -5,6 +5,6 @@ import (
)
func main() {
- js.Global().Set("DitherNord", DitherNord())
+ js.Global().Set("dither", Dither())
<-make(chan bool)
}
diff --git a/wasm.go b/src/wasm.go
similarity index 67%
rename from wasm.go
rename to src/wasm.go
index 67524c8..f65962e 100644
--- a/wasm.go
+++ b/src/wasm.go
@@ -2,8 +2,8 @@ package main
import (
"bytes"
- b64 "encoding/base64"
"encoding/hex"
+ "fmt"
"image"
"image/color"
_ "image/jpeg"
@@ -42,6 +42,11 @@ func buildPalette(pal []string) (color.Palette, error) {
if err != nil {
return nil, err
}
+
+ if len(b) != 3 {
+ return nil, fmt.Errorf("invalid color length: %v", len(b))
+ }
+
palette[i] = color.RGBA{b[0], b[1], b[2], 0xff}
}
@@ -53,8 +58,7 @@ func ditherImage(img image.Image) image.Image {
ditherer := dither.NewDitherer(nordPalette)
ditherer.Matrix = dither.FloydSteinberg
- // Dither image in a copy
- dst := ditherer.DitherCopy(img)
+ dst := ditherer.Dither(img)
return dst
}
@@ -68,9 +72,9 @@ func decodeImage(imageData []byte) (image.Image, error) {
return img, nil
}
-// DittherNord returns a Promise that takes a UintArray containing a Jpeg or png image,
-// and resolves to a string containing a base64 encoded png image.
-func DitherNord() js.Func {
+// Dither returns a Promise that takes a UintArray containing a Jpeg or png image,
+// and resolves to a UintArray containing the dithered image.
+func Dither() js.Func {
return js.FuncOf(func(this js.Value, args []js.Value) interface{} {
imageBytes := make([]byte, args[0].Length())
js.CopyBytesToGo(imageBytes, args[0])
@@ -80,6 +84,8 @@ func DitherNord() js.Func {
reject := args[1]
go func() {
+ errorConstructor := js.Global().Get("Error")
+
// Decode image from raw bytes
img, err := decodeImage(imageBytes)
if err != nil {
@@ -96,12 +102,25 @@ func DitherNord() js.Func {
log.Printf("Image dithered in %v\n", t2.Sub(t1))
// Encode as PNG
+ log.Println("Encoding image...")
+ t1 = time.Now()
buf := new(bytes.Buffer)
- png.Encode(buf, ditheredImage)
+ err = png.Encode(buf, ditheredImage)
+ if err != nil {
+ log.Printf("Error encoding image: %v\n", err)
+ errorObject := errorConstructor.New(err.Error())
+ reject.Invoke(errorObject)
+ }
+ t2 = time.Now()
+ log.Printf("Image encoded in %v\n", t2.Sub(t1))
- // Encode as img src b64 string and resolve
- encodedImage := b64.StdEncoding.EncodeToString(buf.Bytes())
- resolve.Invoke(js.ValueOf(encodedImage))
+ log.Println("Copying image to JS...")
+ t1 = time.Now()
+ encodedImage := js.Global().Get("Uint8ClampedArray").New(len(buf.Bytes()))
+ js.CopyBytesToJS(encodedImage, buf.Bytes())
+ t2 = time.Now()
+ log.Printf("Image copied in %v\n", t2.Sub(t1))
+ resolve.Invoke(encodedImage)
}()
return nil
diff --git a/wasm-palette-converter.code-workspace b/wasm-palette-converter.code-workspace
new file mode 100644
index 0000000..db83d3c
--- /dev/null
+++ b/wasm-palette-converter.code-workspace
@@ -0,0 +1,11 @@
+{
+ "folders": [
+ {
+ "path": "./src"
+ },
+ {
+ "path": "./client"
+ }
+],
+ "settings": {}
+}
+
+
+ Open in new tab
+
+