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TAChart: Calculate transformation coefficients iteratively

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git-svn-id: trunk@31709 -
This commit is contained in:
ask 2011-07-16 16:17:26 +00:00
parent f13bf300dd
commit d4b0f89e8f
2 changed files with 36 additions and 38 deletions
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44
components/tachart/tachartaxis.pas
View File

@ -132,7 +132,7 @@ type
function GetChart: TCustomChart; inline;
function IsVertical: Boolean; inline;
procedure Measure(
ADrawer: IChartDrawer; const AExtent: TDoubleRect; AFirstPass: Boolean;
ADrawer: IChartDrawer; const AExtent: TDoubleRect;
var AMeasureData: TChartAxisGroup);
published
property Alignment default calLeft;
@ -189,9 +189,8 @@ type
var AIndex: Integer);
function GetAxis(AIndex: Integer): TChartAxis;
function GetEnumerator: TChartAxisEnumerator;
procedure Measure(
ADrawer: IChartDrawer; const AExtent: TDoubleRect;
AFirstPass: Boolean; var AMargins: TChartAxisMargins);
function Measure(
ADrawer: IChartDrawer; const AExtent: TDoubleRect): TChartAxisMargins;
procedure Prepare(ARect: TRect);
procedure PrepareGroups;
procedure SetAxis(AIndex: Integer; AValue: TChartAxis);
@ -209,7 +208,7 @@ type
TAxisCoeffHelper = object
FAxis: TChartAxis;
FImageLo, FImageHi, FMarginLo, FMarginHi: Integer;
FImageLo, FImageHi: Integer;
FLo, FHi: Integer;
FMin, FMax: PDouble;
function CalcOffset(AScale: Double): Double;
@ -529,11 +528,9 @@ end;
procedure TChartAxis.Measure(
ADrawer: IChartDrawer; const AExtent: TDoubleRect;
AFirstPass: Boolean; var AMeasureData: TChartAxisGroup);
var AMeasureData: TChartAxisGroup);
function MaxMarksSize(AMin, AMax: Double): TPoint;
const
SOME_DIGIT = '0';
var
t: String;
begin
@ -541,16 +538,8 @@ procedure TChartAxis.Measure(
if AMin = AMax then exit;
GetMarkValues(AMin, AMax);
if not Marks.Visible then exit;
for t in FMarkTexts do begin
// CalculateTransformationCoeffs changes axis interval, so it is possibile
// that a new mark longer then existing ones is introduced.
// That will change marks width and reduce view area,
// requiring another call to CalculateTransformationCoeffs...
// So punt for now and just reserve space for extra digit unconditionally.
if AFirstPass then
t += SOME_DIGIT;
for t in FMarkTexts do
Result := MaxPoint(Marks.MeasureLabel(ADrawer, t), Result);
end;
end;
function TitleSize: Integer;
@ -757,22 +746,22 @@ begin
AList.Sort(ACompare);
end;
procedure TChartAxisList.Measure(
ADrawer: IChartDrawer; const AExtent: TDoubleRect;
AFirstPass: Boolean; var AMargins: TChartAxisMargins);
function TChartAxisList.Measure(
ADrawer: IChartDrawer; const AExtent: TDoubleRect): TChartAxisMargins;
var
g: ^TChartAxisGroup;
procedure UpdateMarginsForMarks(AFirst, ALast: TChartAxisAlignment);
begin
AMargins[AFirst] := Max(AMargins[AFirst], g^.FFirstMark);
AMargins[ALast] := Max(AMargins[ALast], g^.FLastMark);
Result[AFirst] := Max(Result[AFirst], g^.FFirstMark);
Result[ALast] := Max(Result[ALast], g^.FLastMark);
end;
var
i, j, ai: Integer;
axis: TChartAxis;
begin
FillChar(Result, SizeOf(Result), 0);
ai := 0;
for i := 0 to High(FGroups) do begin
g := @FGroups[i];
@ -782,11 +771,10 @@ begin
g^.FTitleSize := 0;
for j := 0 to g^.FCount - 1 do begin
axis := TChartAxis(FGroupOrder[ai]);
axis.Measure(ADrawer, AExtent, AFirstPass, g^);
axis.Measure(ADrawer, AExtent, g^);
ai += 1;
end;
if AFirstPass then
AMargins[axis.Alignment] += g^.FSize + g^.FTitleSize;
Result[axis.Alignment] += g^.FSize + g^.FTitleSize;
end;
ai := 0;
for i := 0 to High(FGroups) do begin
@ -872,12 +860,10 @@ begin
FAxis := AAxis;
FImageLo := AImageLo;
FImageHi := AImageHi;
FMarginLo := AMarginLo;
FMarginHi := AMarginHi;
FMin := AMin;
FMax := AMax;
FLo := FImageLo + FMarginLo;
FHi := FImageHi + FMarginHi;
FLo := FImageLo + AMarginLo;
FHi := FImageHi + AMarginHi;
end;
function TAxisCoeffHelper.CalcScale(ASign: Integer): Double;

30
components/tachart/tagraph.pas
View File

@ -1104,8 +1104,11 @@ end;
procedure TChart.PrepareAxis(ADrawer: IChartDrawer);
var
axisMargin: TChartAxisMargins = (0, 0, 0, 0);
axisMargin: TChartAxisMargins;
a: TChartAxisAlignment;
cr: TRect;
tries: Integer;
prevExt: TDoubleRect;
begin
if not AxisVisible then begin
FClipRect.Left += Depth;
@ -1114,15 +1117,24 @@ begin
exit;
end;
// There is a cyclic dependency: extent -> visible marks -> margins.
// We recalculate them iteratively hoping that the process converges.
AxisList.PrepareGroups;
AxisList.Measure(ADrawer, CurrentExtent, true, axisMargin);
axisMargin[calLeft] := Max(axisMargin[calLeft], Depth);
axisMargin[calBottom] := Max(axisMargin[calBottom], Depth);
for a := Low(a) to High(a) do
SideByAlignment(FClipRect, a, -axisMargin[a]);
CalculateTransformationCoeffs(GetMargins(ADrawer));
AxisList.Measure(ADrawer, CurrentExtent, false, axisMargin);
CalculateTransformationCoeffs(Rect(0, 0, 0, 0));
cr := FClipRect;
for tries := 1 to 10 do begin
axisMargin := AxisList.Measure(ADrawer, CurrentExtent);
axisMargin[calLeft] := Max(axisMargin[calLeft], Depth);
axisMargin[calBottom] := Max(axisMargin[calBottom], Depth);
FClipRect := cr;
for a := Low(a) to High(a) do
SideByAlignment(FClipRect, a, -axisMargin[a]);
prevExt := FCurrentExtent;
FCurrentExtent := FLogicalExtent;
CalculateTransformationCoeffs(GetMargins(ADrawer));
if prevExt = FCurrentExtent then break;
prevExt := FCurrentExtent;
end;
AxisList.Prepare(FClipRect);
end;