THPDFPage.DrawArc Method

THPDFPage.DrawArc

沿指定 rectangle 圍成的 ellipse perimeter 繪製 arc

Delphi 語法：

function DrawArc( X1, Y1, X2, Y2, X3, Y3, X4, Y4: Single ):TCurrPoint;

TCurrPoint Type Definition

THPDFCurrPoint defines a point in page coordinates

Unit
HPDFDoc

type
    THPDFCurrPoint = record
        X: Extended;
        Y: Extended;
    end;

Description:
The THPDFCurrPoint type defines a location on the PDF page. X specifies the horizontal coordinate and Y specifies the vertical coordinate.

C++ 語法：

TCurrPoint __fastcall DrawArc( float X1, float Y1, float X2, float Y2, float X3, float Y3, float X4, float Y4 );

說明

使用 DrawArc 繪製 elliptically curved line。arc 會沿由 (X1,Y1) 與 (X2,Y2) 圍成的 ellipse perimeter，從起點到終點以 counterclockwise 方向繪製。起點由 ellipse 與通過 ellipse center 及 (X3,Y3) 的 line 交點定義；終點由 ellipse 與通過 ellipse center 及 (X4, Y4) 的 line 交點定義

Code Example

program ArcExample;
{$APPTYPE CONSOLE}
uses
    SysUtils, Graphics, Classes, HPDFDoc;
var
    HPDF: THotPDF;
begin
    HPDF := THotPDF.Create( nil );
    try
        HPDF.AutoLaunch := true;                                                    // PDF file will be shown automatically
        HPDF.FileName := '.\Curve.pdf';                                             // Set PDF filename
        HPDF.BeginDoc;                                                              // Create PDF file
        HPDF.CurrentPage.DrawArc(10, 10, 110, 110, 50, 10, 10, 50); // Draw Arc
        HPDF.CurrentPage.Stroke;                                                    // Stroke curve
        HPDF.EndDoc;                                                                // Close PDF file
    finally
        HPDF.Free;
    end;
end.