Consistent text mode for bar-like & pie-like traces and feature to control text orientation inside pie/sunburst slices

src/lib/index.js

@@ -1182,31 +1182,48 @@ lib.isHidden = function(gd) {
     return !display || display === 'none';
 };
 
-lib.getTextTransform = function(opts) {
-    var textX = opts.textX;
-    var textY = opts.textY;
-    var targetX = opts.targetX;
-    var targetY = opts.targetY;
-    var scale = opts.scale;
-    var rotate = opts.rotate;
-
-    var transformScale;
-    var transformRotate;
-    var transformTranslate;
-
-    if(scale < 1) transformScale = 'scale(' + scale + ') ';
-    else {
-        scale = 1;
-        transformScale = '';
-    }
-
-    transformRotate = (rotate) ?
-        'rotate(' + rotate + ' ' + textX + ' ' + textY + ') ' : '';
-
-    // Note that scaling also affects the center of the text box
-    var translateX = (targetX - scale * textX);
-    var translateY = (targetY - scale * textY);
-    transformTranslate = 'translate(' + translateX + ' ' + translateY + ')';
+/** Return transform text for bar bar-like rectangles and pie-like slices
+ *  @param {object} transform
+ *  - targetX: desired position on the x-axis
+ *  - targetY: desired position on the y-axis
+ *  - textX: width of text
+ *  - textY: height of text
+ *  - scale: (optional) scale applied after translate
+ *  - rotate: (optional) rotation applied after scale
+ *  - noCenter: when defined no extra arguments needed in rotation
+ */
+lib.getTextTransform = function(transform) {
+    var noCenter = transform.noCenter;
+    var textX = transform.textX;
+    var textY = transform.textY;
+    var targetX = transform.targetX;
+    var targetY = transform.targetY;
+    var rotate = transform.rotate;
+    var scale = transform.scale;
+    if(!scale) scale = 0;
+    else if(scale > 1) scale = 1;
+
+    return (
+        'translate(' +
+            (targetX - scale * textX) + ',' +
+            (targetY - scale * textY) +
+        ')' +
+        (scale < 1 ?
+            'scale(' + scale + ')' : ''
+        ) +
+        (rotate ?
+            'rotate(' + rotate +
+                (noCenter ? '' : ' ' + textX + ' ' + textY) +
+            ')' : ''
+        )
+    );
+};
 
-    return transformTranslate + transformScale + transformRotate;
+lib.ensureUniformFontSize = function(gd, baseFont) {
+    var out = lib.extendFlat({}, baseFont);
+    out.size = Math.max(
+        baseFont.size,
+        gd._fullLayout.uniformtext.minsize || 0
+    );
+    return out;
 };

src/plots/layout_attributes.js

@@ -140,6 +140,36 @@ module.exports = {
         }),
         editType: 'layoutstyle'
     },
+    uniformtext: {
+        mode: {
+            valType: 'enumerated',
+            values: [false, 'hide', 'show'],
+            dflt: false,
+            role: 'info',
+            editType: 'plot',
+            description: [
+                'Determines how the font size for various text',
+                'elements are uniformed between each trace type.',
+                'If the computed text sizes were smaller than',
+                'the minimum size defined by `uniformtext.minsize`',
+                'using *hide* option hides the text; and',
+                'using *show* option shows the text without further downscaling.',
+                'Please note that if the size defined by `minsize` is greater than',
+                'the font size defined by trace, then the `minsize` is used.'
+            ].join(' ')
+        },
+        minsize: {
+            valType: 'number',
+            min: 0,
+            dflt: 0,
+            role: 'info',
+            editType: 'plot',
+            description: [
+                'Sets the minimum text size between traces of the same type.'
+            ].join(' ')
+        },
+        editType: 'plot'
+    },
     autosize: {
         valType: 'boolean',
         role: 'info',

src/plots/plots.js

@@ -1472,6 +1472,11 @@ plots.supplyLayoutGlobalDefaults = function(layoutIn, layoutOut, formatObj) {
     coerce('title.pad.b');
     coerce('title.pad.l');
 
+    var uniformtextMode = coerce('uniformtext.mode');
+    if(uniformtextMode) {
+        coerce('uniformtext.minsize');
+    }
+
     // Make sure that autosize is defaulted to *true*
     // on layouts with no set width and height for backward compatibly,
     // in particular https://plot.ly/javascript/responsive-fluid-layout/

src/traces/bar/plot.js

@@ -237,14 +237,14 @@ function plot(gd, plotinfo, cdModule, traceLayer, opts, makeOnCompleteCallback)
     Registry.getComponentMethod('errorbars', 'plot')(gd, bartraces, plotinfo, opts);
 }
 
-function appendBarText(gd, plotinfo, bar, calcTrace, i, x0, x1, y0, y1, opts, makeOnCompleteCallback) {
+function appendBarText(gd, plotinfo, bar, cd, i, x0, x1, y0, y1, opts, makeOnCompleteCallback) {
     var xa = plotinfo.xaxis;
     var ya = plotinfo.yaxis;
 
     var fullLayout = gd._fullLayout;
     var textPosition;
 
-    function appendTextNode(bar, text, textFont) {
+    function appendTextNode(bar, text, font) {
         var textSelection = Lib.ensureSingle(bar, 'text')
             .text(text)
             .attr({
@@ -254,25 +254,25 @@ function appendBarText(gd, plotinfo, bar, calcTrace, i, x0, x1, y0, y1, opts, ma
                 // tex and regular text together
                 'data-notex': 1
             })
-            .call(Drawing.font, textFont)
+            .call(Drawing.font, font)
             .call(svgTextUtils.convertToTspans, gd);
 
         return textSelection;
     }
 
     // get trace attributes
-    var trace = calcTrace[0].trace;
+    var trace = cd[0].trace;
     var isHorizontal = (trace.orientation === 'h');
 
-    var text = getText(fullLayout, calcTrace, i, xa, ya);
+    var text = getText(fullLayout, cd, i, xa, ya);
     textPosition = getTextPosition(trace, i);
 
     // compute text position
     var inStackOrRelativeMode =
         opts.mode === 'stack' ||
         opts.mode === 'relative';
 
-    var calcBar = calcTrace[i];
+    var calcBar = cd[i];
     var isOutmostBar = !inStackOrRelativeMode || calcBar._outmost;
 
     if(!text ||
@@ -285,7 +285,7 @@ function appendBarText(gd, plotinfo, bar, calcTrace, i, x0, x1, y0, y1, opts, ma
     }
 
     var layoutFont = fullLayout.font;
-    var barColor = style.getBarColor(calcTrace[i], trace);
+    var barColor = style.getBarColor(cd[i], trace);
     var insideTextFont = style.getInsideTextFont(trace, i, layoutFont, barColor);
     var outsideTextFont = style.getOutsideTextFont(trace, i, layoutFont);
 
@@ -318,6 +318,7 @@ function appendBarText(gd, plotinfo, bar, calcTrace, i, x0, x1, y0, y1, opts, ma
     var textBB;
     var textWidth;
     var textHeight;
+    var font;
 
     if(textPosition === 'outside') {
         if(!isOutmostBar && !calcBar.hasB) textPosition = 'inside';
@@ -327,7 +328,10 @@ function appendBarText(gd, plotinfo, bar, calcTrace, i, x0, x1, y0, y1, opts, ma
         if(isOutmostBar) {
             // draw text using insideTextFont and check if it fits inside bar
             textPosition = 'inside';
-            textSelection = appendTextNode(bar, text, insideTextFont);
+
+            font = Lib.ensureUniformFontSize(gd, insideTextFont);
+
+            textSelection = appendTextNode(bar, text, font);
 
             textBB = Drawing.bBox(textSelection.node()),
             textWidth = textBB.width,
@@ -357,9 +361,9 @@ function appendBarText(gd, plotinfo, bar, calcTrace, i, x0, x1, y0, y1, opts, ma
     }
 
     if(!textSelection) {
-        textSelection = appendTextNode(bar, text,
-                (textPosition === 'outside') ?
-                outsideTextFont : insideTextFont);
+        font = Lib.ensureUniformFontSize(gd, (textPosition === 'outside') ? outsideTextFont : insideTextFont);
+
+        textSelection = appendTextNode(bar, text, font);
 
         var currentTransform = textSelection.attr('transform');
         textSelection.attr('transform', '');
@@ -374,32 +378,61 @@ function appendBarText(gd, plotinfo, bar, calcTrace, i, x0, x1, y0, y1, opts, ma
         }
     }
 
+    var angle = trace.textangle;
+
     // compute text transform
     var transform, constrained;
     if(textPosition === 'outside') {
         constrained =
             trace.constraintext === 'both' ||
             trace.constraintext === 'outside';
 
-        transform = Lib.getTextTransform(toMoveOutsideBar(x0, x1, y0, y1, textBB, {
+        transform = toMoveOutsideBar(x0, x1, y0, y1, textBB, {
             isHorizontal: isHorizontal,
             constrained: constrained,
-            angle: trace.textangle
-        }));
+            angle: angle
+        });
     } else {
         constrained =
             trace.constraintext === 'both' ||
             trace.constraintext === 'inside';
 
-        transform = Lib.getTextTransform(toMoveInsideBar(x0, x1, y0, y1, textBB, {
+        transform = toMoveInsideBar(x0, x1, y0, y1, textBB, {
             isHorizontal: isHorizontal,
             constrained: constrained,
-            angle: trace.textangle,
+            angle: angle,
             anchor: trace.insidetextanchor
-        }));
+        });
     }
 
-    transition(textSelection, opts, makeOnCompleteCallback).attr('transform', transform);
+    transform.fontSize = font.size;
+    recordMinTextSize(trace.type, transform, fullLayout);
+    calcBar.transform = transform;
+
+    transition(textSelection, opts, makeOnCompleteCallback)
+        .attr('transform', Lib.getTextTransform(transform));
+}
+
+function recordMinTextSize(
+    traceType, // in
+    transform, // inout
+    fullLayout // inout
+) {
+    if(fullLayout.uniformtext.mode) {
+        var minKey = '_' + traceType + 'Text_minsize';
+        var minSize = fullLayout.uniformtext.minsize;
+        var size = transform.scale * transform.fontSize;
+
+        transform.hide = size < minSize;
+
+        fullLayout[minKey] = fullLayout[minKey] || Infinity;
+        if(!transform.hide) {
+            fullLayout[minKey] = Math.min(
+                fullLayout[minKey],
+                Math.max(size, minSize)
+            );
+        }
+    }
 }
 
 function getRotateFromAngle(angle) {
@@ -549,15 +582,15 @@ function toMoveOutsideBar(x0, x1, y0, y1, textBB, opts) {
     };
 }
 
-function getText(fullLayout, calcTrace, index, xa, ya) {
-    var trace = calcTrace[0].trace;
+function getText(fullLayout, cd, index, xa, ya) {
+    var trace = cd[0].trace;
     var texttemplate = trace.texttemplate;
 
     var value;
     if(texttemplate) {
-        value = calcTexttemplate(fullLayout, calcTrace, index, xa, ya);
+        value = calcTexttemplate(fullLayout, cd, index, xa, ya);
     } else if(trace.textinfo) {
-        value = calcTextinfo(calcTrace, index, xa, ya);
+        value = calcTextinfo(cd, index, xa, ya);
     } else {
         value = helpers.getValue(trace.text, index);
     }
@@ -570,8 +603,8 @@ function getTextPosition(trace, index) {
     return helpers.coerceEnumerated(attributeTextPosition, value);
 }
 
-function calcTexttemplate(fullLayout, calcTrace, index, xa, ya) {
-    var trace = calcTrace[0].trace;
+function calcTexttemplate(fullLayout, cd, index, xa, ya) {
+    var trace = cd[0].trace;
     var texttemplate = Lib.castOption(trace, index, 'texttemplate');
     if(!texttemplate) return '';
     var isWaterfall = (trace.type === 'waterfall');
@@ -599,7 +632,7 @@ function calcTexttemplate(fullLayout, calcTrace, index, xa, ya) {
         return tickText(vAxis, +v, true).text;
     }
 
-    var cdi = calcTrace[index];
+    var cdi = cd[index];
     var obj = {};
 
     obj.label = cdi.p;
@@ -640,8 +673,8 @@ function calcTexttemplate(fullLayout, calcTrace, index, xa, ya) {
     return Lib.texttemplateString(texttemplate, obj, fullLayout._d3locale, pt, obj, trace._meta || {});
 }
 
-function calcTextinfo(calcTrace, index, xa, ya) {
-    var trace = calcTrace[0].trace;
+function calcTextinfo(cd, index, xa, ya) {
+    var trace = cd[0].trace;
     var isHorizontal = (trace.orientation === 'h');
     var isWaterfall = (trace.type === 'waterfall');
     var isFunnel = (trace.type === 'funnel');
@@ -657,7 +690,7 @@ function calcTextinfo(calcTrace, index, xa, ya) {
     }
 
     var textinfo = trace.textinfo;
-    var cdi = calcTrace[index];
+    var cdi = cd[index];
 
     var parts = textinfo.split('+');
     var text = [];
@@ -666,7 +699,7 @@ function calcTextinfo(calcTrace, index, xa, ya) {
     var hasFlag = function(flag) { return parts.indexOf(flag) !== -1; };
 
     if(hasFlag('label')) {
-        text.push(formatLabel(calcTrace[index].p));
+        text.push(formatLabel(cd[index].p));
     }
 
     if(hasFlag('text')) {
@@ -717,5 +750,5 @@ function calcTextinfo(calcTrace, index, xa, ya) {
 module.exports = {
     plot: plot,
     toMoveInsideBar: toMoveInsideBar,
-    toMoveOutsideBar: toMoveOutsideBar
+    recordMinTextSize: recordMinTextSize
 };