Method _updateEffectAnimation

src/chart/helper/EffectLine.ts:112–163

(
        lineData: SeriesData,
        effectModel: Model<LineDrawModelOption['effect']>,
        idx: number
    )

    }

    private _updateEffectAnimation(
        lineData: SeriesData,
        effectModel: Model<LineDrawModelOption['effect']>,
        idx: number
    ) {

        const symbol = this.childAt(1) as ECSymbolOnEffectLine;
        if (!symbol) {
            return;
        }

        const points = lineData.getItemLayout(idx);

        let period = effectModel.get('period') * 1000;
        const loop = effectModel.get('loop');
        const roundTrip = effectModel.get('roundTrip');
        const constantSpeed = effectModel.get('constantSpeed');
        const delayExpr = zrUtil.retrieve(effectModel.get('delay'), function (idx) {
            return idx / lineData.count() * period / 3;
        });

        // Ignore when updating
        symbol.ignore = true;

        this._updateAnimationPoints(symbol, points);

        if (constantSpeed > 0) {
            period = this._getLineLength(symbol) / constantSpeed * 1000;
        }

        if (period !== this._period || loop !== this._loop || roundTrip !== this._roundTrip) {
            symbol.stopAnimation();
            let delayNum: number;
            if (zrUtil.isFunction(delayExpr)) {
                delayNum = delayExpr(idx);
            }
            else {
                delayNum = delayExpr;
            }
            if (symbol.__t > 0) {
                delayNum = -period * symbol.__t;
            }

            this._animateSymbol(
                symbol, period, delayNum, loop, roundTrip
            );
        }

        this._period = period;
        this._loop = loop;
        this._roundTrip = roundTrip;
    }

    private _animateSymbol(
        symbol: ECSymbolOnEffectLine, period: number, delayNum: number, loop: boolean, roundTrip: boolean) {