Steema Central

1. Grildline are cutted for negative values
x -10 10
y -10 10

For negative x and y you see no gird lines
for negative x only vertical lines are drawn
for negative y only horizontal lines are drawn

uses TeeSurfa;

procedure TForm1.FormCreate(Sender: TObject);
var x, z: Integer;
    Series1: TColorGridSeries;
begin
  Series1:=TColorGridSeries.Create(Self);
  Series1.IrregularGrid:=True;
  Chart1.AddSeries(Series1);

  for x:=-10 to 10 do
    for z:=-10 to 10 do
      Series1.AddXYZ(x, random, z);
end;

2. If the TColorgrid is the last series in chart
ALL TAnnotations get a background color from a color (the last?) of the TColorgrid.
I think in the TAnnotations drawing function forgets to set the correct brush.

uses TeeSurfa, TeeTools;

procedure TForm1.FormCreate(Sender: TObject);
var x, z: Integer;
    Series1: TColorGridSeries;
begin
  Series1:=TColorGridSeries.Create(Self);
  Series1.IrregularGrid:=True;
  Chart1.AddSeries(Series1);

  for x:=-10 to 10 do
    for z:=-10 to 10 do
      Series1.AddXYZ(x, random, z);

  Chart1.Tools.Add(TAnnotationTool.Create(Self));
  (Chart1.Tools[0] as TAnnotationTool).Text:='My annotation';
end;

3. No really a bug but no very uses full.

The Marks configuration with one "Draw every" makes no sense.
You get interesting patters!
A Draw every X and DrawEvery Y configuration would be better.

As I see the TColorgrid works in general not in inregular grid mode with negative values (althought the values are filled regular means äquidistant).
The colorfields are show only in the positive quadrant.

This restriction is a great loss especially because the very beauty smoothing function does not work in irregular mode.

Working with negative values would be a wish of mine for the next version, too.