Angled label white space and start of label cut off.

[biqpaulson]

Hello,

Is there anything we can do about:

• Angled labels causing a large amount of white space under the chart
• Beginning of long angled labels being cut off.

If the labels are small (one character here) then it looks like:

ChartWithSmallLabel.PNG (18.32 KiB) Viewed 12325 times

If the labels are long then the two issues are seen:

ChartWithLongLabel.PNG (19.78 KiB) Viewed 12326 times

The Red rectangle is the white space and grows with label length.
The Blue rectangle shows the cut of of the label on the left of the panel.

• Make a new form.
• Add a TChart.
• Add a trackbar.
• Add the code below.
  The code I used is:

  Code: Select all

  using System;
  using System.Collections.Generic;
  using System.ComponentModel;
  using System.Data;
  using System.Drawing;
  using System.Linq;
  using System.Text;
  using System.Threading.Tasks;
  using System.Windows.Forms;
  using Steema.TeeChart;
  
  namespace NoRefreshOnHorizBar
  {
      public partial class Form1 : Form
      {
          private const string LONG_TEXT_STRING = "aBcDe FgHiJkL MnOpQrS tUvWx Yz";
          //        private Steema.TeeChart.Styles.Bar TheSeries;
          private Steema.TeeChart.Styles.Bar TheSeries;
          public Form1()
          {
              InitializeComponent();
          }
  
          private void Form1_Load(object sender, EventArgs e)
          {
              SetupTrackBar();
              SetupChart();
          }
  
          private void SetupTrackBar()
          {
              trackBar1.Minimum = 1;
              trackBar1.Maximum = LONG_TEXT_STRING.Length;
              trackBar1.Value = 1;
          }
  
          private void SetupChart()
          {
              tChart1.Aspect.View3D = false;
              tChart1.Legend.Visible = false;
              tChart1.Axes.Bottom.Labels.Angle = 30;
              tChart1.Axes.Bottom.Labels.Separation = 0;
              tChart1.Axes.Bottom.FixedLabelSize = false;
              TheSeries = new Steema.TeeChart.Styles.Bar();
              for (int ii = 0; ii < 10; ii++)
              {
                  TheSeries.Add(ii, LONG_TEXT_STRING.Substring(0, trackBar1.Value));
              }
              tChart1.Series.Add(TheSeries);
  
              TheSeries.Marks.Visible = false;
  
              ResetLabels();
          }
  
          private void ResetLabels()
          {
              if (TheSeries == null) return;
  
              for (int jj = 0; jj < TheSeries.Labels.Count; jj++)
              {
                  TheSeries.Labels[jj] = LONG_TEXT_STRING.Substring(0,trackBar1.Value);
              }
              tChart1.Refresh();
          }
  
          private void trackBar1_Scroll(object sender, EventArgs e)
          {
              ResetLabels();
          }
      }
  }
  

[Christopher]

Hello,

For the red rectangle you can use the GetAxesChartRect to customize the size of the Chart Rectangle, e.g.:

Code: Select all

    Line series;
    private void InitializeChart()
    {
      series = new Line(tChart1.Chart);

      tChart1.Legend.Visible = false;

      for (int i = 0; i < 10; i++)
      {
        series.Add(i, i, "This is a relatively long string for a label");
      }

      tChart1.Axes.Bottom.Labels.Angle = 45;
      tChart1.GetAxesChartRect += TChart1_GetAxesChartRect;
    }

    private void TChart1_GetAxesChartRect(object sender, GetAxesChartRectEventArgs e)
    {
      Rectangle rect = e.AxesChartRect;
      rect.Height += 90;
      e.AxesChartRect = rect;
    }

As for the blue rectangle, I'm not sure exactly what you would like to do about it - could you please give me a clearer indication of what you would expect to see?

[biqpaulson]

Hi:

For the "blue" example, it seems to me that when you (steema) scale the chart to fit in the panel, you would want to take into consideration angled labels, since the outside bounds of the label are larger than the chart.left. Therefore, the chart should be scaled so it fits.

Thanks

[biqpaulson]

I am a little concerned about the white space (red rectangle) fix. Does this mean that you want me to figure out what percentage is being lost each time the user changes the size of the label and somehow calculate that value, subtract the calculated value from the oversized chart?

For one character the white space looks like it could be correct. For each subsequent character that the user might add we would have to know how much white space is being added per character being added.

1) Won't we then have to remove this need space shrinkage once Steema fixes the growth problem?
2) Can you explain what is making the growth of white space and how much we need to calculate to remove each time a new character is added?

[Christopher]

For the "blue" example, it seems to me that when you (steema) scale the chart to fit in the panel, you would want to take into consideration angled labels, since the outside bounds of the label are larger than the chart.left. Therefore, the chart should be scaled so it fits.

Just to confirm: that if the label cannot be rendered fully on the chart left, it should not be rendered at all? If so, I will add this as a feature request.

[Christopher]

1) Won't we then have to remove this need space shrinkage once Steema fixes the growth problem.
2) Can you explain what is making the growth of white space and how much we need to calculate to remove each time a new character is added?

There is a chance these two questions are related - that is, once a reliable algorithm has been determined to calculated the vertical height of a label at an angle, then the issue may be solved on both your side and ours. We will look into such an algorithm, and have entered the issue in our issue-tracking database with id=1815.

[biqpaulson]

For the "blue" example, it seems to me that when you (steema) scale the chart to fit in the panel, you would want to take into consideration angled labels, since the outside bounds of the label are larger than the chart.left. Therefore, the chart should be scaled so it fits.

Just to confirm: that if the label cannot be rendered fully on the chart left, it should not be rendered at all? If so, I will add this as a feature request.

If the label and chart can be displayed by scaling the chart smaller, the answer is no. If the label still does not fit then the answer is yes.