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TAChart: Add TPieSeries.FindContainingSlice function. Extract Measure helper method.

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git-svn-id: trunk@28548 -
This commit is contained in:
ask 2010-11-28 19:41:13 +00:00
parent 486fd0201f
commit 7fcd05e49f
2 changed files with 143 additions and 60 deletions
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7
components/tachart/tachartutils.pas
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@ -242,6 +242,8 @@ function PointDistY(const A, B: TPoint): Integer; inline;
function ProjToRect(
const APt: TDoublePoint; const ARect: TDoubleRect): TDoublePoint;
function RadToDeg16(ARad: Double): Integer; inline;
function RectIntersectsRect(
var ARect: TDoubleRect; const AFixed: TDoubleRect): Boolean;
@ -675,6 +677,11 @@ begin
Result.Y := EnsureRange(APt.Y, ARect.a.Y, ARect.b.Y);
end;
function RadToDeg16(ARad: Double): Integer;
begin
Result := Round(RadToDeg(ARad) * 16);
end;
function RectIntersectsRect(
var ARect: TDoubleRect; const AFixed: TDoubleRect): Boolean;

196
components/tachart/taseries.pas
View File

@ -29,7 +29,7 @@ unit TASeries;
interface
uses
Classes, Graphics,
Classes, Graphics, Types,
TAChartUtils, TADrawUtils, TACustomSeries, TALegend, TATypes;
const
@ -85,19 +85,29 @@ type
read FZeroLevel write SetZeroLevel stored IsZeroLevelStored;
end;
TPieBasicDrawData = class
end;
{ TPieSeries }
TPieSeries = class(TChartSeries)
private
FDrawData: TPieBasicDrawData;
FExploded: Boolean;
procedure Measure(ACanvas: TCanvas);
procedure SetExploded(const AValue: Boolean);
function SliceColor(AIndex: Integer): TColor;
protected
procedure AfterAdd; override;
procedure GetLegendItems(AItems: TChartLegendItems); override;
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
public
function AddPie(Value: Double; Text: String; Color: TColor): Longint;
procedure Draw(ACanvas: TCanvas); override;
function FindContainingSlice(const APoint: TPoint): Integer;
published
// Offset slices away from center based on X value.
property Exploded: Boolean read FExploded write SetExploded default false;
@ -296,8 +306,27 @@ type
implementation
uses
GraphMath, LResources, Math, PropEdits, SysUtils, Types,
TAGraph;
GraphMath, LResources, Math, PropEdits, SysUtils,
TAGraph, TASources;
type
TLabelParams = record
FSize: TSize;
FText: String;
end;
TPieSlice = record
FAngle: Double;
FOffset: TPoint;
end;
TPieDrawData = class(TPieBasicDrawData)
private
FCenter: TPoint;
FLabels: array of TLabelParams;
FRadius: Integer;
FSlices: array of TPieSlice;
end;
{ TLineSeries }
@ -859,41 +888,21 @@ begin
ParentChart.BottomAxis.Visible := false;
end;
constructor TPieSeries.Create(AOwner: TComponent);
begin
inherited Create(AOwner);
FDrawData := TPieDrawData.Create;
end;
destructor TPieSeries.Destroy;
begin
FreeAndNil(FDrawData);
inherited Destroy;
end;
procedure TPieSeries.Draw(ACanvas: TCanvas);
var
labelWidths, labelHeights: TIntegerDynArray;
labelTexts: TStringDynArray;
procedure Measure(out ACenter: TPoint; out ARadius: Integer);
const
MARGIN = 8;
var
i: Integer;
begin
SetLength(labelWidths, Count);
SetLength(labelHeights, Count);
SetLength(labelTexts, Count);
for i := 0 to Count - 1 do begin
labelTexts[i] := FormattedMark(i);
with Marks.MeasureLabel(ACanvas, labelTexts[i]) do begin
labelWidths[i] := cx;
labelHeights[i] := cy;
end;
end;
with ParentChart do begin
ACenter := CenterPoint(ClipRect);
// Reserve space for labels.
ARadius := Min(
ClipRect.Right - ACenter.x - MaxIntValue(labelWidths),
ClipRect.Bottom - ACenter.y - MaxIntValue(labelHeights));
end;
if Marks.IsMarkLabelsVisible then
ARadius -= Marks.Distance;
ARadius := Max(ARadius - MARGIN, 0);
if Exploded then
ARadius := Trunc(ARadius / (Max(Source.Extent.b.X, 0) + 1));
end;
d: TPieDrawData;
function LabelExtraDist(AAngle: Double; AIndex: Integer): Double;
const
@ -904,56 +913,77 @@ var
begin
z := ZeroDoublePoint;
e := RotatePoint(DoublePoint(ALMOST_INF, 0), AAngle + Pi);
r.a.X := -labelWidths[AIndex] / 2;
r.a.X := -d.FLabels[AIndex].FSize.cx / 2;
r.b.X := -r.a.X;
r.a.Y := -labelHeights[AIndex] / 2;
r.a.Y := -d.FLabels[AIndex].FSize.cy / 2;
r.b.Y := -r.a.Y;
LineIntersectsRect(z, e, r);
Result := Norm([e.X, e.Y]);
end;
var
i, radius: Integer;
i: Integer;
prevAngle: Double = 0;
d, angleStep, sliceCenterAngle: Double;
c, center: TPoint;
ed, sliceCenterAngle: Double;
c: TPoint;
prevLabelPoly: TPointArray = nil;
const
RAD_TO_DEG16 = 360 * 16;
begin
if IsEmpty then exit;
Measure(center, radius);
Measure(ACanvas);
d := FDrawData as TPieDrawData;
for i := 0 to Count - 1 do begin
ACanvas.Pen.Color := clBlack;
ACanvas.Pen.Style := psSolid;
ACanvas.Brush.Style := bsSolid;
ACanvas.Brush.Color := SliceColor(i);
with Source[i]^ do begin
angleStep := Y / Source.ValuesTotal * RAD_TO_DEG16;
sliceCenterAngle := prevAngle + angleStep / 2;
if Exploded and (X > 0) then
c := LineEndPoint(center, sliceCenterAngle, radius * X)
else
c := center;
with d.FSlices[i] do begin
sliceCenterAngle := (prevAngle + FAngle / 2);
c := d.FCenter + FOffset;
ACanvas.RadialPie(
c.x - d.FRadius, c.y - d.FRadius, c.x + d.FRadius, c.y + d.FRadius,
RadToDeg16(prevAngle), RadToDeg16(FAngle));
prevAngle += FAngle;
end;
ACanvas.RadialPie(
c.x - radius, c.y - radius, c.x + radius, c.y + radius,
round(prevAngle), round(angleStep));
prevAngle += angleStep;
if not Marks.IsMarkLabelsVisible then continue;
d := LabelExtraDist(DegToRad(sliceCenterAngle / 16), i);
ed := LabelExtraDist(sliceCenterAngle, i);
Marks.DrawLabel(
ACanvas,
LineEndPoint(c, sliceCenterAngle, radius),
LineEndPoint(c, sliceCenterAngle, radius + Marks.Distance + d),
labelTexts[i], prevLabelPoly);
LineEndPoint(c, RadToDeg16(sliceCenterAngle), d.FRadius),
LineEndPoint(c, RadToDeg16(sliceCenterAngle), d.FRadius + Marks.Distance + ed),
d.FLabels[i].FText, prevLabelPoly);
end;
end;
function TPieSeries.FindContainingSlice(const APoint: TPoint): Integer;
var
prevAngle: Double = 0;
c: TPoint;
d: TPieDrawData;
pointAngle: Double;
begin
if IsEmpty then exit(-1);
d := FDrawData as TPieDrawData;
for Result := 0 to Count - 1 do
with d.FSlices[Result] do begin
c := APoint - d.FCenter - FOffset;
pointAngle := ArcTan2(-c.Y, c.X);
if pointAngle < 0 then
pointAngle += 2 * Pi;
if
InRange(pointAngle - prevAngle, 0, FAngle) and
(Sqr(c.X) + Sqr(c.Y) <= Sqr(d.FRadius))
then
exit;
prevAngle += FAngle;
end;
Result := -1;
end;
procedure TPieSeries.GetLegendItems(AItems: TChartLegendItems);
var
i: Integer;
@ -975,6 +1005,52 @@ begin
end;
end;
procedure TPieSeries.Measure(ACanvas: TCanvas);
const
MARGIN = 8;
var
i: Integer;
d: TPieDrawData;
m: TPoint = (X: 0; Y: 0);
di: PChartDataItem;
prevAngle: Double = 0;
begin
d := FDrawData as TPieDrawData;
SetLength(d.FLabels, Count);
SetLength(d.FSlices, Count);
for i := 0 to Count - 1 do
with d.FLabels[i] do begin
FText := FormattedMark(i);
FSize := Marks.MeasureLabel(ACanvas, FText);
m.X := Max(m.X, FSize.cx);
m.Y := Max(m.Y, FSize.cy);
end;
d.FCenter := CenterPoint(ParentChart.ClipRect);
// Reserve space for labels.
m := ParentChart.ClipRect.BottomRight - d.FCenter - m;
d.FRadius := Min(m.X, m.Y);
if Marks.IsMarkLabelsVisible then
d.FRadius -= Marks.Distance;
d.FRadius := Max(d.FRadius - MARGIN, 0);
if Exploded then
d.FRadius := Trunc(d.FRadius / (Max(Source.Extent.b.X, 0) + 1));
for i := 0 to Count - 1 do begin
di := Source[i];
with d.FSlices[i] do begin
FAngle := CycleToRad(di^.Y / Source.ValuesTotal);
FOffset := Point(0, 0);
if Exploded and (di^.X > 0) then begin
FOffset.X := Round(d.FRadius * di^.X);
FOffset := RotatePoint(FOffset, prevAngle + FAngle / 2);
FOffset.Y := - FOffset.Y;
end;
prevAngle += FAngle;
end;
end;
end;
procedure TPieSeries.SetExploded(const AValue: Boolean);
begin
if FExploded = AValue then exit;