Function getItemAlign

src/component/visualMap/helper.ts:40–72

(
    visualMapModel: VisualMapModel,
    api: ExtensionAPI,
    itemSize: number[]
)

 * @return {string} 'left' or 'right' or 'top' or 'bottom'
 */
export function getItemAlign(
    visualMapModel: VisualMapModel,
    api: ExtensionAPI,
    itemSize: number[]
): ItemAlign {
    const modelOption = visualMapModel.option;
    const itemAlign = modelOption.align;

    if (itemAlign != null && itemAlign !== 'auto') {
        return itemAlign as ItemAlign;
    }

    // Auto decision align.
    const ecSize = {width: api.getWidth(), height: api.getHeight()};
    const realIndex = modelOption.orient === 'horizontal' ? 1 : 0;

    const reals = paramsSet[realIndex];
    const fakeValue = [0, null, 10];

    const layoutInput = {} as Record<ItemAlign, number | string>;
    for (let i = 0; i < 3; i++) {
        layoutInput[paramsSet[1 - realIndex][i]] = fakeValue[i];
        layoutInput[reals[i]] = i === 2 ? itemSize[0] : modelOption[reals[i]];
    }

    const rParam = ([['x', 'width', 3], ['y', 'height', 0]] as const)[realIndex];
    const rect = getLayoutRect(layoutInput, ecSize, modelOption.padding);

    return reals[
        (rect.margin[rParam[2]] || 0) + rect[rParam[0]] + rect[rParam[1]] * 0.5
            < ecSize[rParam[1]] * 0.5 ? 0 : 1
    ];
}

/**
 * Prepare dataIndex for outside usage, where dataIndex means rawIndex, and