Method brush

src/common/overlay/levelRenderer/SmicImage.js:64–176

* @function LevelRenderer.Shape.SmicImage.prototype.buildPath * @description 创建图片。 * * @param {CanvasRenderingContext2D} ctx - Context2D 上下文。 * @param {Object} style - style。 *

(ctx, isHighlight, refresh)

     *
     */
    brush(ctx, isHighlight, refresh) {
        if (!this.refOriginalPosition || this.refOriginalPosition.length !== 2) {
            this.refOriginalPosition = [0, 0];
        }
        var __OP = this.refOriginalPosition;

        var style = this.style || {};

        if (isHighlight) {
            // 根据style扩展默认高亮样式
            style = this.getHighlightStyle(
                style, this.highlightStyle || {}
            );
        }

        var image = style.image;
        var me = this;

        if (typeof(image) === 'string') {
            var src = image;
            if (this._imageCache[src]) {
                image = this._imageCache[src];
            } else {
                image = new Image();
                image.onload = function () {
                    image.onload = null;
                    clearTimeout(SmicImage._refreshTimeout);
                    SmicImage._needsRefresh.push(me);
                    // 防止因为缓存短时间内触发多次onload事件
                    SmicImage._refreshTimeout = setTimeout(function () {
                        refresh && refresh(SmicImage._needsRefresh);
                        // 清空 needsRefresh
                        SmicImage._needsRefresh = [];
                    }, 10);
                };

                image.src = src;
                this._imageCache[src] = image;
            }
        }
        if (image) {
            // 图片已经加载完成
            if (image.nodeName.toUpperCase() == 'IMG') {
                if (window.ActiveXObject) {
                    if (image.readyState != 'complete') {
                        return;
                    }
                } else {
                    if (!image.complete) {
                        return;
                    }
                }
            }
            // Else is canvas
            var width = style.width || image.width;
            var height = style.height || image.height;
            var x = style.x + __OP[0];
            var y = style.y + __OP[1];