就修改了下你截图的这段代码
//setup debug draw
var debugDraw = new b2DebugDraw();
//创建一个画板
var canvas = Laya.Browser.createElement('canvas');
//设置大小
canvas.width = Laya.stage.width;
canvas.height = Laya.stage.height;
var ctx = canvas.getContext('2d');
Laya.stage.graphics.clear(false);
var textture = new Laya.Texture(canvas);
textture.bitmap.alwaysChange = true;//小游戏使用,非常费,每帧刷新
Laya.stage.graphics.drawTexture(textture);
debugDraw.SetSprite(ctx);
debugDraw.SetDrawScale(30.0);
debugDraw.SetFillAlpha(0.3);
debugDraw.SetLineThickness(1.0);
debugDraw.SetFlags(b2DebugDraw.e_shapeBit | b2DebugDraw.e_jointBit);
world.SetDebugDraw(debugDraw);
window.setInterval(update, 1000 / 60);
小游戏还需要改下Box2D.js源码,在附件第二个中有改过,直接使用即可,顺便说下,Laya开发群文件中的Box2D_TS版就是我发的,也是基于此版本改的