function dataEach(data, idx) {
            var itemModel = data.getItemModel(idx);
            var symbolType = normalize$2(itemModel.getShallow('symbol', true));
            var symbolSize = normalize$2(itemModel.getShallow('symbolSize', true));
            var opacity = itemModel.get(opacityQuery);

            symbolType[0] && data.setItemVisual(idx, 'fromSymbol', symbolType[0]);
            symbolType[1] && data.setItemVisual(idx, 'toSymbol', symbolType[1]);
            symbolSize[0] && data.setItemVisual(idx, 'fromSymbolSize', symbolSize[0]);
            symbolSize[1] && data.setItemVisual(idx, 'toSymbolSize', symbolSize[1]);

            data.setItemVisual(idx, 'opacity', opacity);
        }
get canvas of a black circle brush used for canvas to draw later
@private
@returns {Object} circle brush canvas