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TAChart: refactor bar series drawing

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git-svn-id: trunk@18851 -
This commit is contained in:
ask 2009-03-01 09:04:48 +00:00
parent 2580f132b8
commit 7385883003
2 changed files with 52 additions and 67 deletions
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9
components/tachart/tachartutils.pas
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@ -104,6 +104,9 @@ function EqualPoints(const A, B: TPoint): Boolean; inline;
procedure Exchange(var A, B: Integer); overload;
procedure Exchange(var A, B: Double); overload;
// True if float ranges [A, B] and [C, D] have at least one common point.
function FloatRangesOverlap(A, B, C, D: Double): Boolean; inline;
function PointDist(const A, B: TPoint): Integer; inline;
function PointDistX(const A, B: TPoint): Integer; inline;
@ -207,6 +210,12 @@ begin
B := t;
end;
function FloatRangesOverlap(A, B, C, D: Double): Boolean; inline;
begin
Result := (A <= D) and (C <= B);
end;
function PointDist(const A, B: TPoint): Integer;
begin
Result := Sqr(A.X - B.X) + Sqr(A.Y - B.Y);

110
components/tachart/taseries.pas
View File

@ -1208,87 +1208,63 @@ end;
procedure TBarSeries.Draw(ACanvas: TCanvas);
var
XMin, XMax: Integer;
i: Integer;
graphCoordTop: TChartCoord;
graphCoordBottom: TChartCoord;
topX, topY, bottomY: Integer;
barX, barTopY, barBottomY: Double;
barWidth, totalbarWidth, totalBarSeries, myPos: Integer;
bx1, by1, bx2, by2: Integer;
function BarInViewPort(cTop, cBottom: TChartCoord): Boolean;
begin //FIXME make cleaner?
Result :=
((cTop.x >= ParentChart.XGraphMin) and (cTop.x <= ParentChart.XGraphMax)) and
( ((cTop.y > ParentChart.YGraphMax) and (cBottom.y < ParentChart.YGraphMin))
or ( (cTop.y < ParentChart.YGraphMax) and (cTop.y > ParentChart.YGraphMin))
or ( (cBottom.y < ParentChart.YGraphMax) and (cBottom.y > ParentChart.YGraphMin))
);
end;
r: TRect;
begin
//no elements to draw
if FCoordList.Count = 0 then exit;
//get the limits (for the zoom) ??
XMin := ParentChart.XImageMin;
XMax := ParentChart.XImageMax;
if XMin > XMax then
Exchange(XMin, XMax);
// Draw the bars
ACanvas.Pen.Assign(FBarPen);
ACanvas.Brush.Assign(FBarBrush);
//calc the single bar width
// Calculate the single bar width.
totalbarWidth :=
Round((FBarWidthPercent * 0.01) * ParentChart.ChartWidth / FCoordList.Count);
Round(FBarWidthPercent * 0.01 * ParentChart.ChartWidth / FCoordList.Count);
ExamineAllBarSeries(totalBarSeries, myPos);
barWidth := totalbarWidth div totalBarSeries;
ACanvas.Brush.Assign(BarBrush);
if barWidth > 2 then
ACanvas.Pen.Assign(BarPen)
else begin
// Bars are too narrow to distinguish border from interior.
ACanvas.Pen.Color := BarBrush.Color;
ACanvas.Pen.Style := psSolid;
end;
for i := 0 to FCoordList.Count - 1 do begin
//get the top and bottom points
if TChartCoord(FCoordList.Items[i]^).y >= 0 then begin
graphCoordTop := TChartCoord(FCoordList.Items[i]^);
graphCoordBottom.x := graphCoordTop.x;
graphCoordBottom.y := 0;
end else begin
graphCoordBottom := TChartCoord(FCoordList.Items[i]^);
graphCoordTop.x := graphCoordBottom.x;
graphCoordTop.y := 0;
with PChartCoord(FCoordList.Items[i])^ do begin
barX := x;
barTopY := y;
end;
barBottomY := 0;
if barTopY < barBottomY then
Exchange(barTopY, barBottomY);
with ParentChart do begin
// Check if bar is in view port.
if
not InRange(barX, XGraphMin, XGraphMax) or
not FloatRangesOverlap(barBottomY, barTopY, YGraphMin, YGraphMax)
then
continue;
// Only draw to the limits.
if barTopY > YGraphMax then barTopY := YGraphMax;
if barBottomY < YGraphMin then barBottomY := YGraphMin;
//check if bar in view port
if BarInViewPort(graphCoordTop, graphCoordBottom) then begin
//only draw to the limits
if graphCoordTop.y > ParentChart.YGraphMax then graphCoordTop.y := ParentChart.YGraphMax;
if graphCoordBottom.y < ParentChart.YGraphMin then graphCoordBottom.y := ParentChart.YGraphMin;
//convert from graph to imgs coords
ParentChart.GraphToImage(graphCoordTop.x, graphCoordTop.y, topX, topY);
ParentChart.YGraphToImage(graphCoordBottom.y, bottomY);
//calc coords for bar
{ bx1 := topX-(barWidth div 2);
by1 := topY;
bx2 := topX+(barWidth div 2);
by2 := bottomY;
}
bx1 := topX - (totalbarWidth div 2) + myPos * barWidth;
by1 := topY;
bx2 := topX - (totalbarWidth div 2) + myPos * barWidth + barWidth;
by2 := bottomY;
//FIXME only draw if bar inside image coord (get a better way of doing this)
if (bx1 >= XMin) and (bx2 <= XMax) then
if by1 = by2 then begin //draw a line when y=0 FIXME (clean)
ACanvas.Pen.Color := FBarBrush.Color;
ACanvas.MoveTo(bx1, by1);
ACanvas.LineTo(bx2, by2);
ACanvas.Pen.Assign(FBarPen);
end else
ACanvas.Rectangle( bx1, by1, bx2, by2);
GraphToImage(barX, barTopY, r.Left, r.Top);
YGraphToImage(barBottomY, r.Bottom);
end;
end; // for
// Adjust for multiple bar series.
r.Left += myPos * barWidth - totalbarWidth div 2;
r.Right := r.Left + barWidth;
// Draw a line instead of an empty rectangle.
if r.Bottom = r.Top then Inc(r.Bottom);
if r.Left = r.Right then Inc(r.Right);
ACanvas.Rectangle(r);
end;
end;
procedure TBarSeries.DrawLegend(ACanvas: TCanvas; const ARect: TRect);