尝试为递归函数实现内联 Webworker [英] Trying to implement inline Webworker for a recursive function
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问题描述
我有第一个版本，在 Javascript 中使用递归函数会产生预期的结果.在工作版本以下:
I have a first version of using a recursive function with Javascript which produces expected results. Below a working version :
// Call the recursive function and get final (a,b) results
var HitTemp = JSON.parse(JSON.stringify(HitCurrent));
var result= recursiveFunction(HitTemp, HitTemp.playerCurrent, maxNodes);
var a = HitTemp.coordPlayable[0];
var b = HitTemp.coordPlayable[1];
// Recursive function
function recursiveFunction(HitCurrent, colorCurrent, depth) {
// Indices
var i, j, k;
// Evaluation
var arrayTemp, eval, e;
// Set current color to HitCurrent
HitCurrent.playerCurrent = colorCurrent;
// Deep copy of arrayCurrent array
arrayTemp = JSON.parse(JSON.stringify(HitCurrent.arrayCurrent));
// If depth equal to 0
if (depth == 0)
return evaluation(HitCurrent);
// Starting evaluation
eval = -infinity;
// Browse all possible hits
for (i = 0; i < 8; i++)
for (j = 0; j < 8; j++) {
if (HitCurrent.arrayPlayable[i][j] == 'playable') {
for (k = 0; k < 8; k++) {
// Explore line started from (i,j) with direction "k"
exploreHitLine(HitCurrent, i, j, k, 'drawing');
}
// Recursive call
e = recursiveFunction(JSON.parse(JSON.stringify(HitCurrent)), ((JSON.stringify(HitCurrent.playerCurrent) == JSON.stringify(playerBlack)) ? playerWhite : playerBlack), depth-1);
if (e > eval) {
HitCurrent.coordPlayable = [i,j];
eval = e;
}
}
// Restore arrayCurrent array
HitCurrent.arrayCurrent = JSON.parse(JSON.stringify(arrayTemp));
}
return eval;
}
由此，我想使用内联"WebWorkers 将递归专用于 WebWorker 并避免在浏览器中挂起进程.
From this, I would like to use "inline" WebWorkers to dedicate the recursion to WebWorker and avoid hanging process in browsers.
我不知道我是否必须postmessage"对象HitCurrent 或值eval 到主线程:通过使用WebWorker，我混淆了 return 指令(在终端情况下返回一个值)和为下一次递归调用传递的对象 HitCurrent 参数.
I don't know if I have to "postmessage" the object HitCurrent or the value eval to the main thread : by using WebWorker, I make confusions between the return instruction (which returns a value in the terminal case) and the objet HitCurrent argument passed for next recursive call.
如果有人可以通过使用内联 webworker(或使用 webworker 的经典方式)提供一些线索来重现这个原始算法.
If someone could give some clues to reproduce this original algorithm by using inline webworker (or with classical way of using webworker).
推荐答案
内联 webworker 示例:
Inline webworker example:
作为你的代码，没有函数求值、function exploreHitLine.在使用以下代码之前，您必须将它们插入code.
As your code, there is no function evaluation, function exploreHitLine.
Before use following code, you must insert them into code.
{
let workerScript = URL.createObjectURL( new Blob( [ `
"use strict";
// Recursive function
function recursiveFunction( HitCurrent, colorCurrent, depth ) {
// Indices
var i, j, k;
// Evaluation
var arrayTemp, eval, e;
// Set current color to HitCurrent
HitCurrent.playerCurrent = colorCurrent;
// Deep copy of arrayCurrent array
arrayTemp = JSON.parse(JSON.stringify(HitCurrent.arrayCurrent));
// If depth equal to 0
if ( depth === 0 ) return evaluation(HitCurrent);
// Starting evaluation
eval = -infinity;
// Browse all possible hits
for (i = 0; i < 8; i++) {
for (j = 0; j < 8; j++) {
if (HitCurrent.arrayPlayable[i][j] === 'playable') {
for (k = 0; k < 8; k++) {
// Explore line started from (i,j) with direction "k"
exploreHitLine(HitCurrent, i, j, k, 'drawing');
}
// Recursive call
e = recursiveFunction(JSON.parse(JSON.stringify(HitCurrent)), ((JSON.stringify(HitCurrent.playerCurrent) == JSON.stringify(playerBlack)) ? playerWhite : playerBlack), depth-1);
if (e > eval) {
HitCurrent.coordPlayable = [i,j];
eval = e;
}
}
// Restore arrayCurrent array
HitCurrent.arrayCurrent = JSON.parse(JSON.stringify(arrayTemp));
}
}
return eval;
}
onmessage = function ( event ) {
let params = event.data;
postMessage( { result: recursiveFunction( ...params ) } );
}
` ], { type: "plain/text" } ) );
// Call the recursive function and get final (a,b) results
new Promise( resolve => {
let HitTemp = JSON.parse(JSON.stringify(HitCurrent));
let firstWorker = new Worker( workerScript );
firstWorker.onmessage = function ( event ) {
resolve( event.data ); //{ result: XXX }
}
firstWorker.postMessage( HitTemp, HitTemp.playerCurrent, maxNodes );
} ).then( ( { result } ) => {
let [ a, b ] = result.coordPlayable;
console.log( result );
} );
}
另外以下是工作内联 WebWorker:
Additionally following is working inline WebWorker:
{
let workerScript = URL.createObjectURL( new Blob( [ `
"use strict";
onmessage = function ( event ) {
let sum = 0, count = event.data;
for ( let i = 0; i < count**count; i++ ) {
sum += i;
}
postMessage( { result: sum, count } );
}
` ], { type: "plain/text" } ) );
let firstWorker = new Worker( workerScript );
let firstAlive = setTimeout( () => {
firstWorker.terminate();
console.log( "terminated" );
}, 3000 );
firstWorker.onmessage = function ( event ) {
clearTimeout( firstAlive );
console.log( event.data );
}
firstWorker.postMessage( 10 );
let secondWorker = new Worker( workerScript );
let secondAlive = setTimeout( () => {
secondWorker.terminate();
console.log( "terminated" );
}, 3000 );
secondWorker.onmessage = function ( event ) {
clearTimeout( secondAlive );
console.log( event.data );
}
secondWorker.postMessage( 5 );
}更新 1.
{
// Inline webworker version
let workerScript = URL.createObjectURL( new Blob( [ `
"use strict";
// Recursive function
function recursiveFunction( HitCurrent, colorCurrent, depth ) {
// Indices
var i, j, k;
// Evaluation
var arrayTemp, evaluated, e;
// Set current color to HitCurrent
HitCurrent.playerCurrent = colorCurrent;
// Deep copy of arrayCurrent array
arrayTemp = JSON.parse(JSON.stringify(HitCurrent.arrayCurrent));
// If depth equal to 0
if (depth == 0)
return evaluation(HitCurrent);
// Starting evaluation
evaluated = -infinity;
// Browse all possible hits
for (i = 0; i < 8; i++) {
for (j = 0; j < 8; j++) {
if (HitCurrent.arrayPlayable[i][j] == 'playable') {
for (k = 0; k < 8; k++) {
// Explore line started from (i,j) with direction "k"
exploreHitLine(HitCurrent, i, j, k, 'drawing');
}
// Recursive call
e = recursiveFunction(JSON.parse(JSON.stringify(HitCurrent)), ((JSON.stringify(HitCurrent.playerCurrent) == JSON.stringify(playerBlack)) ? playerWhite : playerBlack), depth-1);
if ( e > evaluated ) {
HitCurrent.coordPlayable = [i,j];
evaluated = e;
}
if (e == -infinity) { HitCurrent.coordPlayable = [ i, j ]; }
// Restore arrayCurrent array
HitCurrent.arrayCurrent = JSON.parse(JSON.stringify(arrayTemp));
}
}
}
return evaluated;
}
onmessage = function ( event ) {
let params = event.data;
//postMessage( { result: recursiveFunction( HitCurrent, HitCurrent.playerCurrent, maxNodes ) } );
postMessage( { result: recursiveFunction( ...params ) } );
};
` ], { type: "plain/text" } ) );
// Call the recursive function and get final (a,b) results
new Promise( resolve => {
let HitTemp = JSON.parse(JSON.stringify(HitCurrent));
let firstWorker = new Worker( workerScript );
firstWorker.onmessage = function ( event ) {
resolve( event.data ); //{ result: XXX }
}
firstWorker.postMessage( [ HitTemp, HitTemp.playerCurrent, maxNodes ] );
} ).then( ( { result } ) => {
let [ a, b ] = result.coordPlayable;
console.log( result );
} );
}对我的错误的解释:
- 在严格模式"下，不能使用eval"作为变量名.
=>
来自:eval
到:评估
Worker.postMessage( aMessage, Transferrable )，在这种情况下，您不需要使用第二个参数.
Worker.postMessage( aMessage, Transferrable ), in this case, you don't need to use the second parameter.
=>
来自:firstWorker.postMessage( HitTemp, HitTemp.playerCurrent, maxNodes );
到:firstWorker.postMessage( [ HitTemp, HitTemp.playerCurrent, maxNodes ] );
(https://developer.mozilla.org/en-US/docs/Web/API/Worker/postMessage)
- 继续2，固定传递给recursiveFunction的参数.
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