Laya 踩坑日记-BitmapFont 不显示空格

项目中有用到艺术字，美术通过 bmfont64 将字体导给我了，结果发现在应用上 空格不显示 如图：

今天去深究了一下这个问题，发现是底层没封装好，然后自己改了一下
下面是改过的 BitmapFont 类 在laya.core.js 里面

class BitmapFont {
        constructor() {
            this._fontCharDic = {};
            this._fontWidthMap = {};
            this._maxWidth = 0;
            this._spaceWidth = 10;
            this.fontSize = 12;
            this.autoScaleSize = false;
            this.letterSpacing = 0;
        }
        loadFont(path, complete) {
            this._path = path;
            this._complete = complete;
            if (!path || path.indexOf(".fnt") === -1) {
                console.error('Bitmap font configuration information must be a ".fnt" file');
                return;
            }
            ILaya.loader.load([{ url: path, type: ILaya.Loader.XML }, { url: path.replace(".fnt", ".png"), type: ILaya.Loader.IMAGE }], Handler.create(this, this._onLoaded));
        }
        _onLoaded() {
            this.parseFont(ILaya.Loader.getRes(this._path), ILaya.Loader.getRes(this._path.replace(".fnt", ".png")));
            this._complete && this._complete.run();
        }
        parseFont(xml, texture) {
            if (xml == null || texture == null)
                return;
            this._texture = texture;
            var tScale = 1;
            var tInfo = xml.getElementsByTagName("info");
            if (!tInfo[0].getAttributeNode) {
                return this.parseFont2(xml, texture);
            }
            this.fontSize = parseInt(tInfo[0].getAttributeNode("size").nodeValue);
            var tPadding = tInfo[0].getAttributeNode("padding").nodeValue;
            var tPaddingArray = tPadding.split(",");
            this._padding = [parseInt(tPaddingArray[0]), parseInt(tPaddingArray[1]), parseInt(tPaddingArray[2]), parseInt(tPaddingArray[3])];
            var chars = xml.getElementsByTagName("char");
            var i = 0;
            for (i = 0; i < chars.length; i++) {
                var tAttribute = chars[i];
                var tId = parseInt(tAttribute.getAttributeNode("id").nodeValue);
                var xOffset = parseInt(tAttribute.getAttributeNode("xoffset").nodeValue) / tScale;
                var yOffset = parseInt(tAttribute.getAttributeNode("yoffset").nodeValue) / tScale;
                var xAdvance = parseInt(tAttribute.getAttributeNode("xadvance").nodeValue) / tScale;
                var region = new Rectangle();
                region.x = parseInt(tAttribute.getAttributeNode("x").nodeValue);
                region.y = parseInt(tAttribute.getAttributeNode("y").nodeValue);
                region.width = parseInt(tAttribute.getAttributeNode("width").nodeValue);
                region.height = parseInt(tAttribute.getAttributeNode("height").nodeValue);
                var tTexture = Texture.create(texture, region.x, region.y, region.width, region.height, xOffset, yOffset);
                this._maxWidth = Math.max(this._maxWidth, xAdvance + this.letterSpacing);
                this._fontCharDic[tId] = tTexture;
                this._fontWidthMap[tId] = xAdvance;
            }
        }
        parseFont2(xml, texture) {
            if (xml == null || texture == null)
                return;
            this._texture = texture;
            var tScale = 1;
            var tInfo = xml.getElementsByTagName("info");
            this.fontSize = parseInt(tInfo[0].attributes["size"].nodeValue);
            var tPadding = tInfo[0].attributes["padding"].nodeValue;
            var tPaddingArray = tPadding.split(",");
            this._padding = [parseInt(tPaddingArray[0]), parseInt(tPaddingArray[1]), parseInt(tPaddingArray[2]), parseInt(tPaddingArray[3])];
            var chars = xml.getElementsByTagName("char");
            var i = 0;
            for (i = 0; i < chars.length; i++) {
                var tAttribute = chars[i].attributes;
                var tId = parseInt(tAttribute["id"].nodeValue);
                var xOffset = parseInt(tAttribute["xoffset"].nodeValue) / tScale;
                var yOffset = parseInt(tAttribute["yoffset"].nodeValue) / tScale;
                var xAdvance = parseInt(tAttribute["xadvance"].nodeValue) / tScale;
                var region = new Rectangle();
                region.x = parseInt(tAttribute["x"].nodeValue);
                region.y = parseInt(tAttribute["y"].nodeValue);
                region.width = parseInt(tAttribute["width"].nodeValue);
                region.height = parseInt(tAttribute["height"].nodeValue);
                var tTexture = Texture.create(texture, region.x, region.y, region.width, region.height, xOffset, yOffset);
                this._maxWidth = Math.max(this._maxWidth, xAdvance + this.letterSpacing);
                this._fontCharDic[tId] = tTexture;
                this._fontWidthMap[tId] = xAdvance;
            }
        }
        getCharTexture(char) {
            return this._fontCharDic[char.charCodeAt(0)];
        }
        destroy() {
            if (this._texture) {
                for (var p in this._fontCharDic) {
                    var tTexture = this._fontCharDic[p];
                    if (tTexture)
                        tTexture.destroy();
                }
                this._texture.destroy();
                this._fontCharDic = null;
                this._fontWidthMap = null;
                this._texture = null;
                this._complete = null;
                this._padding = null;
            }
        }
        setSpaceWidth(spaceWidth) {
            this._spaceWidth = spaceWidth;
        }
        getCharWidth(char) {
            var code = char.charCodeAt(0);
            if (this._fontWidthMap[code])
                return this._fontWidthMap[code] + this.letterSpacing;
            if (char === " ")
                return this._spaceWidth + this.letterSpacing;
            return 0;
        }
        getTextWidth(text) {
            var tWidth = 0;
            for (var i = 0, n = text.length; i < n; i++) {
                tWidth += this.getCharWidth(text.charAt(i));
            }
            return tWidth;
        }
        getMaxWidth() {
            return this._maxWidth;
        }
        getMaxHeight() {
            return this.fontSize;
        }
        _drawText(text, sprite, drawX, drawY, align, width) {
            var tWidth = this.getTextWidth(text);
            var tTexture;
            var dx = 0;
            align === "center" && (dx = (width - tWidth) / 2);
            align === "right" && (dx = (width - tWidth));
            var tx = 0;
            for (var i = 0, n = text.length; i < n; i++) {
                tTexture = this.getCharTexture(text.charAt(i));
                if (tTexture) {
                    sprite.graphics.drawImage(tTexture, drawX + tx + dx, drawY);
                    tx += this.getCharWidth(text.charAt(i));
                }
                //添加
                else{
                    tx += this.getCharWidth(text.charAt(i));
                }
            }
        }
    }

效果如图：