Function getLayoutRect

src/util/layout.ts:263–390

(
    positionInfo: BoxLayoutOptionMixin & {
        // PENDING:
        //  when width can not be decided but height can be decided and aspect is near Infinity,
        //  or when height can not be decided but width can be decided and aspect is near 0,
        //  the result width or height is near Inifity. It's logically correct, therefore
        //  currently we do not handle it, until bad cases arise.
        //
        // aspect is width / height. But this method does not preserve aspect ratio if
        // both width and height can be decided by the given left/top/bottom/right/width/height.
        // To always preserve aspect ratio, uses `applyPreserveAspect` to process the result.
        aspect?: number
    },
    containerRect: GetLayoutRectInputContainerRect,
    // This is the space from the `containerRect` to the returned bounding rect.
    // Commonly used in option `legend.padding`, `timeline.padding`, `title.padding`,
    //  `visualMap.padding`, ...
    // [NOTICE]:
    //  It's named `margin`, because it's the space that outside the bounding rect. But from
    //  the perspective of the the caller, it's commonly used as the `padding` of a component,
    //  because conventionally background color covers this space.
    // [BEHAVIOR]:
    //  - If width/height is specified, `margin` does not effect them.
    //  - Otherwise, they are calculated based on the rect that `containerRect` shrinked by `margin`.
    //  - left/right/top/bottom are based on the rect that `containerRect` shrinked by `margin`.
    margin?: number | number[]
)

 * Parse position info.
 */
export function getLayoutRect(
    positionInfo: BoxLayoutOptionMixin & {
        // PENDING:
        //  when width can not be decided but height can be decided and aspect is near Infinity,
        //  or when height can not be decided but width can be decided and aspect is near 0,
        //  the result width or height is near Inifity. It's logically correct, therefore
        //  currently we do not handle it, until bad cases arise.
        //
        // aspect is width / height. But this method does not preserve aspect ratio if
        // both width and height can be decided by the given left/top/bottom/right/width/height.
        // To always preserve aspect ratio, uses `applyPreserveAspect` to process the result.
        aspect?: number
    },
    containerRect: GetLayoutRectInputContainerRect,
    // This is the space from the `containerRect` to the returned bounding rect.
    // Commonly used in option `legend.padding`, `timeline.padding`, `title.padding`,
    //  `visualMap.padding`, ...
    // [NOTICE]:
    //  It's named `margin`, because it's the space that outside the bounding rect. But from
    //  the perspective of the the caller, it's commonly used as the `padding` of a component,
    //  because conventionally background color covers this space.
    // [BEHAVIOR]:
    //  - If width/height is specified, `margin` does not effect them.
    //  - Otherwise, they are calculated based on the rect that `containerRect` shrinked by `margin`.
    //  - left/right/top/bottom are based on the rect that `containerRect` shrinked by `margin`.
    margin?: number | number[]
): LayoutRect {
    margin = formatUtil.normalizeCssArray(margin || 0);

    const containerWidth = containerRect.width;
    const containerHeight = containerRect.height;

    let left = parsePercent(positionInfo.left, containerWidth);
    let top = parsePercent(positionInfo.top, containerHeight);
    const right = parsePercent(positionInfo.right, containerWidth);
    const bottom = parsePercent(positionInfo.bottom, containerHeight);
    let width = parsePercent(positionInfo.width, containerWidth);
    let height = parsePercent(positionInfo.height, containerHeight);

    const verticalMargin = margin[2] + margin[0];
    const horizontalMargin = margin[1] + margin[3];
    const aspect = positionInfo.aspect;

    // If width is not specified, calculate width from left and right
    if (isNaN(width)) {
        width = containerWidth - right - horizontalMargin - left;
    }
    if (isNaN(height)) {
        height = containerHeight - bottom - verticalMargin - top;
    }

    if (aspect != null) {
        // If width and height are not given
        // 1. Graph should not exceeds the container
        // 2. Aspect must be keeped
        // 3. Graph should take the space as more as possible
        // FIXME
        // Margin is not considered, because there is no case that both