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TITLE

[Feature] Can legend set the horizontal and vertical intervals separately?

BODY

What problem does this feature solve?

itemGap
The official description of this property is as follows: the interval between each item in the legend. Horizontal intervals in landscape layout and vertical intervals in portrait layout.
However, tests have shown that changing this value will change both the horizontal and longitudinal intervals.

What does the proposed API look like?

I hope that the official provided itemGap supports input arrays, array items are horizontal interval and vertical interval, or provide other feasible solutions, thank you very much.

But after testing, it is found that changing this value will change the horizontal and vertical intervals at the same time.

Could you provide your test code?
Our Demo Code shows correct spacing for the two orient options - horizontal' and 'vertical'.

But after testing, it is found that changing this value will change the horizontal and vertical intervals at the same time.

Could you provide your test code? Our Demo Code shows correct spacing for the two orient options - horizontal' and 'vertical'.

option = {
  dataset: {
    source: [
      ["type", "2012", "2013", "2014", "2015", "2016"],
      ["Forest", 320, 332, 301, 334, 390],
      ["Steppe", 220, 182, 191, 234, 290],
      ["Desert", 150, 232, 201, 154, 190],
      ["Wetland", 98, 77, 101, 99, 40],
       ["AAAAAAA", 98, 77, 101, 99, 40],
        ["BBBBBBB", 98, 77, 101, 99, 40],
         ["CCCCCCC", 98, 77, 101, 99, 40],
         ["DDDDDDD", 98, 77, 101, 99, 40],
         ["EEEEEEE", 98, 77, 101, 99, 40],
         ["FFFFFFF", 98, 77, 101, 99, 40],
         ["GGGGGGG", 98, 77, 101, 99, 40],
         ["HHHHHHH", 98, 77, 101, 99, 40],
         ["IIIIIII", 98, 77, 101, 99, 40],
         ["JJJJJJJ", 98, 77, 101, 99, 40],
         ["KKKKKKK", 98, 77, 101, 99, 40],
    ]
  },
  legend: {
    orient: 'horizontal', 
    itemGap: 50,
  },
  xAxis: {
    type: "category"
  },
  yAxis: {},
  series: [{
    type: "bar",
    seriesLayoutBy: "row"
  }, {
    type: "bar",
    seriesLayoutBy: "row"
  }, {
    type: "bar",
    seriesLayoutBy: "row"
  }, {
    type: "bar",
    seriesLayoutBy: "row"
  },{
    type: "bar",
    seriesLayoutBy: "row"
  },{
    type: "bar",
    seriesLayoutBy: "row"
  },{
    type: "bar",
    seriesLayoutBy: "row"
  },{
    type: "bar",
    seriesLayoutBy: "row"
  },{
    type: "bar",
    seriesLayoutBy: "row"
  },{
    type: "bar",
    seriesLayoutBy: "row"
  },{
    type: "bar",
    seriesLayoutBy: "row"
  },{
    type: "bar",
    seriesLayoutBy: "row"
  },{
    type: "bar",
    seriesLayoutBy: "row"
  },{
    type: "bar",
    seriesLayoutBy: "row"
  },{
    type: "bar",
    seriesLayoutBy: "row"
  },
  
  ]
}

ok, so it is for a legend with many items auto-wrapped on two or more lines. Agree, it's a bug.
Maybe vertical will work better for you:

legend: {
    orient: 'vertical', 
    itemGap: 4, right: 0
  },

ok, so it is for a legend with many items auto-wrapped on two or more lines. Agree, it's a bug. Maybe vertical will work better for you:

legend: {
    orient: 'vertical', 
    itemGap: 4, right: 0
  },

The same goes for vertical.

yes, the bug is there. But when working with many legend items, using smaller itemGap is always better.
I was just looking for a solution/workaround.