lodash-es#isUndefined TypeScript Examples

The following examples show how to use lodash-es#isUndefined. You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.
Example #1
Source File: background.ts    From gosling.js with MIT License 5 votes vote down vote up 
export function drawBackground(
    HGC: any,
    trackInfo: any,
    tile: any,
    tm: GoslingTrackModel,
    theme: Required<CompleteThemeDeep>
) {
    // size and position
    const [l, t] = trackInfo.position;
    const [w, h] = trackInfo.dimensions;

    // refer to https://github.com/higlass/higlass/blob/f82c0a4f7b2ab1c145091166b0457638934b15f3/app/scripts/PixiTrack.js#L129
    const g = trackInfo.pBackground;

    if (tm.spec().style?.background || (theme.track.background && theme.track.background !== 'transparent')) {
        g.clear();

        const bg = tm.spec().style?.background ?? theme.track.background;
        const alpha = isUndefined(tm.spec().style?.backgroundOpacity) ? 1 : tm.spec().style?.backgroundOpacity;
        // background
        g.lineStyle(
            1,
            colorToHex('white'),
            0, // alpha
            0 // alignment of the line to draw, (0 = inner, 0.5 = middle, 1 = outter)
        );
        g.beginFill(colorToHex(bg), alpha);
        g.drawRect(l, t, w, h);
    }

    if (theme.track.alternatingBackground && theme.track.alternatingBackground !== 'transparent') {
        const spec = tm.spec();

        if (!IsChannelDeep(spec.row) || spec.row.type !== 'nominal') {
            // we do not use a `row` channel, so no need to draw alternating backgrounds
            return;
        }

        /* row separation */
        const rowCategories: string[] = (tm.getChannelDomainArray('row') as string[]) ?? ['___SINGLE_ROW___'];
        if (rowCategories.length === 0) {
            // We do not need to fill alternating colors for only one category
            return;
        }

        /* render */
        rowCategories.forEach((category, i) => {
            if (i % 2 === 0) {
                // we only draw even rows
                return;
            }
            const rowPosition = tm.encodedValue('row', category);

            const bg = tm.spec().style?.background ?? theme.track.alternatingBackground;
            const alpha = isUndefined(tm.spec().style?.backgroundOpacity) ? 1 : tm.spec().style?.backgroundOpacity;
            // background
            g.lineStyle(
                1,
                colorToHex('white'),
                0, // alpha
                0 // alignment of the line to draw, (0 = inner, 0.5 = middle, 1 = outter)
            );
            g.beginFill(colorToHex(bg), alpha);
            g.drawRect(trackInfo.position[0], trackInfo.position[1] + rowPosition, w, h / rowCategories.length);
        });
    }
}