egret之弹幕

要实现弹幕功能，首先需要将弹幕配置成配置表。然后代码随机生成。

        /**生成单个弹幕 */
        private showCaptionAnim(captionText: string) {
            egret.log("字幕生成");
            var showCaption_1: egret.TextField = new egret.TextField();
            showCaption_1.text = captionText;
            showCaption_1.textColor = 0Xffffff;
            showCaption_1.size = 40;
            showCaption_1.x = this.stage.stageWidth - 100;
            showCaption_1.y = Fight.GameUtil.getRandomInt(this.gameScene.gamePanel.curNPC.y, this.gameScene.gamePanel.y + this.gameScene.gamePanel.curNPC.height / 2) - 50;
            this.gameScene.gamePanel.captionGroup.visible = true;
            if (this.gameScene.gamePanel.captionGroup) {
                this.gameScene.gamePanel.captionGroup.addChild(showCaption_1);
                // this.gameScene.gamePanel.captionGroup.visible = false;
            }
            this.captionMove(showCaption_1);
        }

        /**控制单个弹幕的移动 */
        private captionMove(text: egret.TextField) {
            if (text != undefined && text != null) {
                let random = Math.floor(Math.random() * 10 + 5);
                egret.Tween.get(text).to({ x: -1300 }, random * 1000).call(() => {
                    egret.Tween.removeTweens(text);
                });
            }
        }
        /**随机弹幕 */
        private randomCaption() {
            //取配置表中的所有弹幕，通过/分割成数组
            let str = GameData.CfgsData.caption.split("/");

            //弹幕概率随机
            let num1 = Math.floor(Math.random() * 10);//0-9
            //0---true  other----false
            if (num1 == 0) {
                this.isCaption = true;
            } else {
                this.isCaption = false;
            }
            if (this.isCaption) {
                let index = Math.floor(Math.random() * str.length);//随机弹幕数组下标
                let currCaption = str[index].toString();
                this.showCaptionAnim(currCaption);
            }
        }

 在需要调用弹幕的时候调用randomCaption函数