v2023.39 (231109) y-axis label issue

[bdw]

Hi,
I've just upgraded from 2021.32.210430 to v2023.39 (231109) which seems to have a y-axis drawing difference.
As the image shows attached the left graph has for example 60.48 on the y-axis while on the previous version this would be 64, 56, 48 etc. Axis min = 0 and max = 65. It draws correctly with more space but if window is small its adding the dp's.
The AxisValueFormat is still the default graph_->LeftAxis->AxisValuesFormat = "###0.###";
I can reduce set ###0 which restricts it but wondering why the values produced are so different ?
Is this an issue with the new VCL TChart ?

[Yeray]

Hello,

I've tried to reproduce the problem with this simple example code without success.

Code: Select all

uses Chart, Series;

var Chart1: TChart;

procedure TForm1.FormCreate(Sender: TObject);
var i: Integer;
begin
  Chart1:=TChart.Create(Self);

  with Chart1 do
  begin
    Parent:=Self;
    Align:=alClient;
    Color:=clWhite;
    Gradient.Visible:=False;
    Walls.Back.Color:=clWhite;
    Walls.Back.Gradient.Visible:=False;
    Legend.Hide;
    View3D:=False;

    with AddSeries(TLineSeries) do
      for i:=0 to 19 do
        Add(Random*65);

    Axes.Left.SetMinMax(0, 65);
    Axes.Left.Title.Text:='Left axis';
  end;
end;

Do you have a simple example project we can run as-is to reproduce the problem here?
Thanks in advance.

[bdw]

Thanks Yeray.
I'll have to dig into the code some more to see what is causing the difference and get back to you.
I was assuming exactly the same code base on our side but will dig some more.

[bdw]

Only just had a chance to re-look at what the code we have is doing.
We also have the Axis.Left.Increment := 1 set in this case to try and reduce the number of y-axis labels rather than automatic.
With that setting in the past it still kept the y-axis labels clean rather than having the in the example 64.8, 57.6 etc
I've not tested that code on the older release yet but will try shortly

[bdw]

Ok I've tested with the two TChart version listed previously and as you can see with the same code the graphs look quite different.
Top one is v2021.x and bottom v2023.x

[bdw]

Ok I have a work around for the present time.
I check the ClientHeight and when its less than 200pixel I set Increment=0 (which is automatic by my testing) for graphs with max - min height < 200 units.
Greater than 200 height units I just set Increment=0

[Yeray]

Hello,

Indeed setting Increment to 1 was the key to reproduce the problem.
I've added it to the public tracker: #2690