lazarus/components/fpvectorial/fpvtocanvas.pas
2012-04-16 14:18:16 +00:00

547 lines
18 KiB
ObjectPascal

unit fpvtocanvas;
{$mode objfpc}{$H+}
interface
{$define USE_LCL_CANVAS}
{$ifdef USE_LCL_CANVAS}
{$define USE_CANVAS_CLIP_REGION}
{.$define DEBUG_CANVAS_CLIP_REGION}
{$endif}
{$ifndef Windows}
{.$define FPVECTORIAL_TOCANVAS_DEBUG}
{$endif}
uses
Classes, SysUtils, Math,
{$ifdef USE_LCL_CANVAS}
Graphics, LCLIntf, LCLType,
{$endif}
fpcanvas,
fpimage,
fpvectorial, fpvutils;
procedure DrawFPVectorialToCanvas(ASource: TvVectorialPage;
ADest: TFPCustomCanvas;
ADestX: Integer = 0; ADestY: Integer = 0; AMulX: Double = 1.0; AMulY: Double = 1.0);
procedure DrawFPVPathToCanvas(ASource: TvVectorialPage; CurPath: TPath;
ADest: TFPCustomCanvas;
ADestX: Integer = 0; ADestY: Integer = 0; AMulX: Double = 1.0; AMulY: Double = 1.0);
procedure DrawFPVEntityToCanvas(ASource: TvVectorialPage; CurEntity: TvEntity;
ADest: TFPCustomCanvas;
ADestX: Integer = 0; ADestY: Integer = 0; AMulX: Double = 1.0; AMulY: Double = 1.0);
procedure DrawFPVTextToCanvas(ASource: TvVectorialPage; CurText: TvText;
ADest: TFPCustomCanvas;
ADestX: Integer = 0; ADestY: Integer = 0; AMulX: Double = 1.0; AMulY: Double = 1.0);
implementation
{@@
This function draws a FPVectorial vectorial image to a TFPCustomCanvas
descendent, such as TCanvas from the LCL.
Be careful that by default this routine does not execute coordinate transformations,
and that FPVectorial works with a start point in the bottom-left corner, with
the X growing to the right and the Y growing to the top. This will result in
an image in TFPCustomCanvas mirrored in the Y axis in relation with the document
as seen in a PDF viewer, for example. This can be easily changed with the
provided parameters. To have the standard view of an image viewer one could
use this function like this:
DrawFPVectorialToCanvas(ASource, ADest, 0, ASource.Height, 1.0, -1.0);
}
procedure DrawFPVectorialToCanvas(ASource: TvVectorialPage;
ADest: TFPCustomCanvas;
ADestX: Integer = 0; ADestY: Integer = 0; AMulX: Double = 1.0; AMulY: Double = 1.0);
var
i: Integer;
CurEntity: TvEntity;
begin
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
WriteLn(':>DrawFPVectorialToCanvas');
{$endif}
for i := 0 to ASource.GetEntitiesCount - 1 do
begin
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
Write(Format('[Path] ID=%d', [i]));
{$endif}
CurEntity := ASource.GetEntity(i);
if CurEntity is TPath then DrawFPVPathToCanvas(ASource, TPath(CurEntity), ADest, ADestX, ADestY, AMulX, AMulY)
else if CurEntity is TvText then DrawFPVTextToCanvas(ASource, TvText(CurEntity), ADest, ADestX, ADestY, AMulX, AMulY)
else DrawFPVEntityToCanvas(ASource, CurEntity, ADest, ADestX, ADestY, AMulX, AMulY);
end;
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
WriteLn(':<DrawFPVectorialToCanvas');
{$endif}
end;
procedure DrawFPVPathToCanvas(ASource: TvVectorialPage; CurPath: TPath;
ADest: TFPCustomCanvas;
ADestX: Integer = 0; ADestY: Integer = 0; AMulX: Double = 1.0; AMulY: Double = 1.0);
function CoordToCanvasX(ACoord: Double): Integer;
begin
Result := Round(ADestX + AmulX * ACoord);
end;
function CoordToCanvasY(ACoord: Double): Integer;
begin
Result := Round(ADestY + AmulY * ACoord);
end;
var
j, k: Integer;
PosX, PosY: Double; // Not modified by ADestX, etc
CoordX, CoordY: Integer;
CurSegment: TPathSegment;
Cur2DSegment: T2DSegment absolute CurSegment;
Cur2DBSegment: T2DBezierSegment absolute CurSegment;
// For bezier
CurX, CurY: Integer; // Not modified by ADestX, etc
CoordX2, CoordY2, CoordX3, CoordY3, CoordX4, CoordY4: Integer;
CurveLength: Integer;
t: Double;
// For polygons
Points: array of TPoint;
// Clipping Region
{$ifdef USE_LCL_CANVAS}
ClipRegion, OldClipRegion: HRGN;
ACanvas: TCanvas absolute ADest;
{$endif}
begin
PosX := 0;
PosY := 0;
ADest.Brush.Style := bsClear;
ADest.MoveTo(ADestX, ADestY);
// Set the path Pen and Brush options
ADest.Pen.Style := CurPath.Pen.Style;
ADest.Pen.Width := Round(CurPath.Pen.Width * AMulX);
if ADest.Pen.Width < 1 then ADest.Pen.Width := 1;
if (CurPath.Pen.Width <= 2) and (ADest.Pen.Width > 2) then ADest.Pen.Width := 2;
if (CurPath.Pen.Width <= 5) and (ADest.Pen.Width > 5) then ADest.Pen.Width := 5;
ADest.Pen.FPColor := CurPath.Pen.Color;
ADest.Brush.FPColor := CurPath.Brush.Color;
// Prepare the Clipping Region, if any
{$ifdef USE_CANVAS_CLIP_REGION}
if CurPath.ClipPath <> nil then
begin
OldClipRegion := LCLIntf.CreateEmptyRegion();
GetClipRgn(ACanvas.Handle, OldClipRegion);
ClipRegion := ConvertPathToRegion(CurPath.ClipPath, ADestX, ADestY, AMulX, AMulY);
SelectClipRgn(ACanvas.Handle, ClipRegion);
DeleteObject(ClipRegion);
// debug info
{$ifdef DEBUG_CANVAS_CLIP_REGION}
ConvertPathToPoints(CurPath.ClipPath, ADestX, ADestY, AMulX, AMulY, Points);
ACanvas.Polygon(Points);
{$endif}
end;
{$endif}
//
// For solid paths, draw a polygon for the main internal area
//
if CurPath.Brush.Style <> bsClear then
begin
CurPath.PrepareForSequentialReading;
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
Write(' Solid Path Internal Area');
{$endif}
ADest.Brush.Style := CurPath.Brush.Style;
SetLength(Points, CurPath.Len);
for j := 0 to CurPath.Len - 1 do
begin
//WriteLn('j = ', j);
CurSegment := TPathSegment(CurPath.Next());
CoordX := CoordToCanvasX(Cur2DSegment.X);
CoordY := CoordToCanvasY(Cur2DSegment.Y);
Points[j].X := CoordX;
Points[j].Y := CoordY;
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
Write(Format(' P%d,%d', [CoordY, CoordY]));
{$endif}
end;
ADest.Polygon(Points);
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
Write(' Now the details ');
{$endif}
end;
//
// For other paths, draw more carefully
//
CurPath.PrepareForSequentialReading;
for j := 0 to CurPath.Len - 1 do
begin
//WriteLn('j = ', j);
CurSegment := TPathSegment(CurPath.Next());
case CurSegment.SegmentType of
stMoveTo:
begin
CoordX := CoordToCanvasX(Cur2DSegment.X);
CoordY := CoordToCanvasY(Cur2DSegment.Y);
ADest.MoveTo(CoordX, CoordY);
PosX := Cur2DSegment.X;
PosY := Cur2DSegment.Y;
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
Write(Format(' M%d,%d', [CoordY, CoordY]));
{$endif}
end;
// This element can override temporarely the Pen
st2DLineWithPen:
begin
ADest.Pen.FPColor := T2DSegmentWithPen(Cur2DSegment).Pen.Color;
CoordX := CoordToCanvasX(PosX);
CoordY := CoordToCanvasY(PosY);
CoordX2 := CoordToCanvasX(Cur2DSegment.X);
CoordY2 := CoordToCanvasY(Cur2DSegment.Y);
ADest.Line(CoordX, CoordY, CoordX2, CoordY2);
PosX := Cur2DSegment.X;
PosY := Cur2DSegment.Y;
ADest.Pen.FPColor := CurPath.Pen.Color;
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
Write(Format(' L%d,%d', [CoordToCanvasX(Cur2DSegment.X), CoordToCanvasY(Cur2DSegment.Y)]));
{$endif}
end;
st2DLine, st3DLine:
begin
CoordX := CoordToCanvasX(PosX);
CoordY := CoordToCanvasY(PosY);
CoordX2 := CoordToCanvasX(Cur2DSegment.X);
CoordY2 := CoordToCanvasY(Cur2DSegment.Y);
ADest.Line(CoordX, CoordY, CoordX2, CoordY2);
PosX := Cur2DSegment.X;
PosY := Cur2DSegment.Y;
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
Write(Format(' L%d,%d', [CoordX, CoordY]));
{$endif}
end;
{ To draw a bezier we need to divide the interval in parts and make
lines between this parts }
st2DBezier, st3DBezier:
begin
CoordX := CoordToCanvasX(PosX);
CoordY := CoordToCanvasY(PosY);
CoordX2 := CoordToCanvasX(Cur2DBSegment.X2);
CoordY2 := CoordToCanvasY(Cur2DBSegment.Y2);
CoordX3 := CoordToCanvasX(Cur2DBSegment.X3);
CoordY3 := CoordToCanvasY(Cur2DBSegment.Y3);
CoordX4 := CoordToCanvasX(Cur2DBSegment.X);
CoordY4 := CoordToCanvasY(Cur2DBSegment.Y);
SetLength(Points, 0);
AddBezierToPoints(
Make2DPoint(CoordX, CoordY),
Make2DPoint(CoordX2, CoordY2),
Make2DPoint(CoordX3, CoordY3),
Make2DPoint(CoordX4, CoordY4),
Points
);
ADest.Brush.Style := CurPath.Brush.Style;
if Length(Points) >= 3 then
ADest.Polygon(Points);
PosX := Cur2DSegment.X;
PosY := Cur2DSegment.Y;
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
Write(Format(' ***C%d,%d %d,%d %d,%d %d,%d',
[CoordToCanvasX(PosX), CoordToCanvasY(PosY),
CoordToCanvasX(Cur2DBSegment.X2), CoordToCanvasY(Cur2DBSegment.Y2),
CoordToCanvasX(Cur2DBSegment.X3), CoordToCanvasY(Cur2DBSegment.Y3),
CoordToCanvasX(Cur2DBSegment.X), CoordToCanvasY(Cur2DBSegment.Y)]));
{$endif}
end;
end;
end;
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
WriteLn('');
{$endif}
// Restores the previous Clip Region
{$ifdef USE_CANVAS_CLIP_REGION}
if CurPath.ClipPath <> nil then
begin
SelectClipRgn(ACanvas.Handle, OldClipRegion); //Using OldClipRegion crashes in Qt
end;
{$endif}
end;
procedure DrawFPVEntityToCanvas(ASource: TvVectorialPage; CurEntity: TvEntity;
ADest: TFPCustomCanvas;
ADestX: Integer = 0; ADestY: Integer = 0; AMulX: Double = 1.0; AMulY: Double = 1.0);
function CoordToCanvasX(ACoord: Double): Integer;
begin
Result := Round(ADestX + AmulX * ACoord);
end;
function CoordToCanvasY(ACoord: Double): Integer;
begin
Result := Round(ADestY + AmulY * ACoord);
end;
var
i: Integer;
{$ifdef USE_LCL_CANVAS}
ALCLDest: TCanvas;
{$endif}
// For entities
CurCircle: TvCircle;
CurEllipse: TvEllipse;
//
CurArc: TvCircularArc;
FinalStartAngle, FinalEndAngle: double;
BoundsLeft, BoundsTop, BoundsRight, BoundsBottom,
IntStartAngle, IntAngleLength, IntTmp: Integer;
//
CurDim: TvAlignedDimension;
Points: array of TPoint;
UpperDim, LowerDim: T3DPoint;
begin
{$ifdef USE_LCL_CANVAS}
ALCLDest := TCanvas(ADest);
{$endif}
if CurEntity is TvEntityWithPenAndBrush then
begin
ADest.Brush.Style := (CurEntity as TvEntityWithPenAndBrush).Brush.Style;
ADest.Brush.FPColor := (CurEntity as TvEntityWithPenAndBrush).Brush.Color;
end;
if CurEntity is TvEntityWithPen then
begin
ADest.Pen.Style := (CurEntity as TvEntityWithPen).Pen.Style;
ADest.Pen.FPColor := (CurEntity as TvEntityWithPen).Pen.Color;
end;
if CurEntity is TvCircle then
begin
CurCircle := CurEntity as TvCircle;
ADest.Ellipse(
CoordToCanvasX(CurCircle.X - CurCircle.Radius),
CoordToCanvasY(CurCircle.Y - CurCircle.Radius),
CoordToCanvasX(CurCircle.X + CurCircle.Radius),
CoordToCanvasY(CurCircle.Y + CurCircle.Radius)
);
end
else if CurEntity is TvCircularArc then
begin
CurArc := CurEntity as TvCircularArc;
{$ifdef USE_LCL_CANVAS}
// ToDo: Consider a X axis inversion
// If the Y axis is inverted, then we need to mirror our angles as well
BoundsLeft := CoordToCanvasX(CurArc.X - CurArc.Radius);
BoundsTop := CoordToCanvasY(CurArc.Y - CurArc.Radius);
BoundsRight := CoordToCanvasX(CurArc.X + CurArc.Radius);
BoundsBottom := CoordToCanvasY(CurArc.Y + CurArc.Radius);
{if AMulY > 0 then
begin}
FinalStartAngle := CurArc.StartAngle;
FinalEndAngle := CurArc.EndAngle;
{end
else // AMulY is negative
begin
// Inverting the angles generates the correct result for Y axis inversion
if CurArc.EndAngle = 0 then FinalStartAngle := 0
else FinalStartAngle := 360 - 1* CurArc.EndAngle;
if CurArc.StartAngle = 0 then FinalEndAngle := 0
else FinalEndAngle := 360 - 1* CurArc.StartAngle;
end;}
IntStartAngle := Round(16*FinalStartAngle);
IntAngleLength := Round(16*(FinalEndAngle - FinalStartAngle));
// On Gtk2 and Carbon, the Left really needs to be to the Left of the Right position
// The same for the Top and Bottom
// On Windows it works fine either way
// On Gtk2 if the positions are inverted then the arcs are screwed up
// In Carbon if the positions are inverted, then the arc is inverted
if BoundsLeft > BoundsRight then
begin
IntTmp := BoundsLeft;
BoundsLeft := BoundsRight;
BoundsRight := IntTmp;
end;
if BoundsTop > BoundsBottom then
begin
IntTmp := BoundsTop;
BoundsTop := BoundsBottom;
BoundsBottom := IntTmp;
end;
// Arc(ALeft, ATop, ARight, ABottom, Angle16Deg, Angle16DegLength: Integer);
{$ifdef FPVECTORIAL_TOCANVAS_DEBUG}
// WriteLn(Format('Drawing Arc Center=%f,%f Radius=%f StartAngle=%f AngleLength=%f',
// [CurArc.CenterX, CurArc.CenterY, CurArc.Radius, IntStartAngle/16, IntAngleLength/16]));
{$endif}
ADest.Pen.FPColor := CurArc.Pen.Color;
ALCLDest.Arc(
BoundsLeft, BoundsTop, BoundsRight, BoundsBottom,
IntStartAngle, IntAngleLength
);
ADest.Pen.FPColor := colBlack;
// Debug info
// {$define FPVECTORIALDEBUG}
// {$ifdef FPVECTORIALDEBUG}
// WriteLn(Format('Drawing Arc x1y1=%d,%d x2y2=%d,%d start=%d end=%d',
// [BoundsLeft, BoundsTop, BoundsRight, BoundsBottom, IntStartAngle, IntAngleLength]));
// {$endif}
{ ADest.TextOut(CoordToCanvasX(CurArc.CenterX), CoordToCanvasY(CurArc.CenterY),
Format('R=%d S=%d L=%d', [Round(CurArc.Radius*AMulX), Round(FinalStartAngle),
Abs(Round((FinalEndAngle - FinalStartAngle)))]));
ADest.Pen.Color := TColor($DDDDDD);
ADest.Rectangle(
BoundsLeft, BoundsTop, BoundsRight, BoundsBottom);
ADest.Pen.Color := clBlack;}
{$endif}
end
else if CurEntity is TvAlignedDimension then
begin
CurDim := CurEntity as TvAlignedDimension;
//
// Draws this shape:
// vertical horizontal
// ___
// | | or ---| X cm
// | --|
// Which marks the dimension
ADest.MoveTo(CoordToCanvasX(CurDim.BaseRight.X), CoordToCanvasY(CurDim.BaseRight.Y));
ADest.LineTo(CoordToCanvasX(CurDim.DimensionRight.X), CoordToCanvasY(CurDim.DimensionRight.Y));
ADest.LineTo(CoordToCanvasX(CurDim.DimensionLeft.X), CoordToCanvasY(CurDim.DimensionLeft.Y));
ADest.LineTo(CoordToCanvasX(CurDim.BaseLeft.X), CoordToCanvasY(CurDim.BaseLeft.Y));
// Now the arrows
// horizontal
SetLength(Points, 3);
if CurDim.DimensionRight.Y = CurDim.DimensionLeft.Y then
begin
ADest.Brush.FPColor := colBlack;
ADest.Brush.Style := bsSolid;
// Left arrow
Points[0] := Point(CoordToCanvasX(CurDim.DimensionLeft.X), CoordToCanvasY(CurDim.DimensionLeft.Y));
Points[1] := Point(Points[0].X + 7, Points[0].Y - 3);
Points[2] := Point(Points[0].X + 7, Points[0].Y + 3);
ADest.Polygon(Points);
// Right arrow
Points[0] := Point(CoordToCanvasX(CurDim.DimensionRight.X), CoordToCanvasY(CurDim.DimensionRight.Y));
Points[1] := Point(Points[0].X - 7, Points[0].Y - 3);
Points[2] := Point(Points[0].X - 7, Points[0].Y + 3);
ADest.Polygon(Points);
ADest.Brush.Style := bsClear;
// Dimension text
Points[0].X := CoordToCanvasX((CurDim.DimensionLeft.X+CurDim.DimensionRight.X)/2);
Points[0].Y := CoordToCanvasY(CurDim.DimensionLeft.Y);
LowerDim.X := CurDim.DimensionRight.X-CurDim.DimensionLeft.X;
ADest.Font.Size := 10;
ADest.TextOut(Points[0].X, Points[0].Y, Format('%.1f', [LowerDim.X]));
end
else
begin
ADest.Brush.FPColor := colBlack;
ADest.Brush.Style := bsSolid;
// There is no upper/lower preference for DimensionLeft/Right, so we need to check
if CurDim.DimensionLeft.Y > CurDim.DimensionRight.Y then
begin
UpperDim := CurDim.DimensionLeft;
LowerDim := CurDim.DimensionRight;
end
else
begin
UpperDim := CurDim.DimensionRight;
LowerDim := CurDim.DimensionLeft;
end;
// Upper arrow
Points[0] := Point(CoordToCanvasX(UpperDim.X), CoordToCanvasY(UpperDim.Y));
Points[1] := Point(Points[0].X + Round(AMulX), Points[0].Y - Round(AMulY*3));
Points[2] := Point(Points[0].X - Round(AMulX), Points[0].Y - Round(AMulY*3));
ADest.Polygon(Points);
// Lower arrow
Points[0] := Point(CoordToCanvasX(LowerDim.X), CoordToCanvasY(LowerDim.Y));
Points[1] := Point(Points[0].X + Round(AMulX), Points[0].Y + Round(AMulY*3));
Points[2] := Point(Points[0].X - Round(AMulX), Points[0].Y + Round(AMulY*3));
ADest.Polygon(Points);
ADest.Brush.Style := bsClear;
// Dimension text
Points[0].X := CoordToCanvasX(CurDim.DimensionLeft.X);
Points[0].Y := CoordToCanvasY((CurDim.DimensionLeft.Y+CurDim.DimensionRight.Y)/2);
LowerDim.Y := CurDim.DimensionRight.Y-CurDim.DimensionLeft.Y;
if LowerDim.Y < 0 then LowerDim.Y := -1 * LowerDim.Y;
ADest.Font.Size := 10;
ADest.TextOut(Points[0].X, Points[0].Y, Format('%.1f', [LowerDim.Y]));
end;
SetLength(Points, 0);
{ // Debug info
ADest.TextOut(CoordToCanvasX(CurDim.BaseRight.X), CoordToCanvasY(CurDim.BaseRight.Y), 'BR');
ADest.TextOut(CoordToCanvasX(CurDim.DimensionRight.X), CoordToCanvasY(CurDim.DimensionRight.Y), 'DR');
ADest.TextOut(CoordToCanvasX(CurDim.DimensionLeft.X), CoordToCanvasY(CurDim.DimensionLeft.Y), 'DL');
ADest.TextOut(CoordToCanvasX(CurDim.BaseLeft.X), CoordToCanvasY(CurDim.BaseLeft.Y), 'BL');}
end
else
CurEntity.Render(ADest, ADestX, ADestY, AMulX, AMulY);
end;
procedure DrawFPVTextToCanvas(ASource: TvVectorialPage; CurText: TvText;
ADest: TFPCustomCanvas;
ADestX: Integer = 0; ADestY: Integer = 0; AMulX: Double = 1.0; AMulY: Double = 1.0);
function CoordToCanvasX(ACoord: Double): Integer;
begin
Result := Round(ADestX + AmulX * ACoord);
end;
function CoordToCanvasY(ACoord: Double): Integer;
begin
Result := Round(ADestY + AmulY * ACoord);
end;
var
i: Integer;
{$ifdef USE_LCL_CANVAS}
ALCLDest: TCanvas;
{$endif}
//
LowerDim: T3DPoint;
begin
{$ifdef USE_LCL_CANVAS}
ALCLDest := TCanvas(ADest);
{$endif}
ADest.Font.Size := Round(AmulX * CurText.Font.Size);
ADest.Pen.Style := psSolid;
ADest.Pen.FPColor := colBlack;
ADest.Brush.Style := bsClear;
{$ifdef USE_LCL_CANVAS}
ALCLDest.Font.Orientation := Round(CurText.Font.Orientation * 16);
{$endif}
// TvText supports multiple lines
for i := 0 to CurText.Value.Count - 1 do
begin
if CurText.Font.Size = 0 then LowerDim.Y := CurText.Y - 12 * (i + 1)
else LowerDim.Y := CurText.Y - CurText.Font.Size * (i + 1);
ADest.TextOut(CoordToCanvasX(CurText.X), CoordToCanvasY(LowerDim.Y), CurText.Value.Strings[i]);
end;
end;
end.