Function findDimensions

src/components/sliders/draw.js:119–245

(gd, sliderOpts)

// Compute the dimensions (mutates sliderOpts):
function findDimensions(gd, sliderOpts) {
    var sliderLabels = Drawing.tester.selectAll('g.' + constants.labelGroupClass)
        .data(sliderOpts._visibleSteps);

    sliderLabels.enter().append('g')
        .classed(constants.labelGroupClass, true);

    // loop over fake buttons to find width / height
    var maxLabelWidth = 0;
    var labelHeight = 0;
    sliderLabels.each(function(stepOpts) {
        var labelGroup = d3.select(this);

        var text = drawLabel(labelGroup, {step: stepOpts}, sliderOpts);

        var textNode = text.node();
        if(textNode) {
            var bBox = Drawing.bBox(textNode);
            labelHeight = Math.max(labelHeight, bBox.height);
            maxLabelWidth = Math.max(maxLabelWidth, bBox.width);
        }
    });

    sliderLabels.remove();

    var dims = sliderOpts._dims = {};

    dims.inputAreaWidth = Math.max(
        constants.railWidth,
        constants.gripHeight
    );

    // calculate some overall dimensions - some of these are needed for
    // calculating the currentValue dimensions
    var graphSize = gd._fullLayout._size;
    dims.lx = graphSize.l + graphSize.w * sliderOpts.x;
    dims.ly = graphSize.t + graphSize.h * (1 - sliderOpts.y);

    if(sliderOpts.lenmode === 'fraction') {
        // fraction:
        dims.outerLength = Math.round(graphSize.w * sliderOpts.len);
    } else {
        // pixels:
        dims.outerLength = sliderOpts.len;
    }

    // The length of the rail, *excluding* padding on either end:
    dims.inputAreaStart = 0;
    dims.inputAreaLength = Math.round(dims.outerLength - sliderOpts.pad.l - sliderOpts.pad.r);

    var textableInputLength = dims.inputAreaLength - 2 * constants.stepInset;
    var availableSpacePerLabel = textableInputLength / (sliderOpts._stepCount - 1);
    var computedSpacePerLabel = maxLabelWidth + constants.labelPadding;
    dims.labelStride = Math.max(1, Math.ceil(computedSpacePerLabel / availableSpacePerLabel));
    dims.labelHeight = labelHeight;

    // loop over all possible values for currentValue to find the
    // area we need for it