(PHP 4, PECL pdflib >= 1.0.0)
PDF_curveto — Draw Bezier curve
$p
, float $x1
, float $y1
, float $x2
, float $y2
, float $x3
, float $y3
)
Draws a Bezier curve from the current point, using 3 more control points.
成功时返回 TRUE， 或者在失败时返回 FALSE。
rune at zedeler dot dk (2005-03-09 19:51:18)
Rod's function does not work (the thing produced is not even symmetrical).
Here is one that produces a correct approximation to an ellipse:
function pdf_ellipse ($pdfobj,$x,$y,$width,$height) {
// Function to draw an ellipse inscribed in a rectangle
// described by lower left (x,y) with width and height.
$fac = (4*sqrt(2)-4)/3;
$dx = $width*(1-$fac)/2;
$dy = $height*(1-$fac)/2;
pdf_moveto($pdfobj, $x,$y+$height/2);
pdf_curveto($pdfobj, $x,$y+$height-$dy, $x+$dx,$y+$height, $x+$width/2,$y+$height);
pdf_curveto($pdfobj, $x+$width-$dx,$y+$height, $x+$width,$y+$height-$dy, $x+$width,$y+$height/2);
pdf_curveto($pdfobj, $x+$width,$y+$dy, $x+$width-$dx,$y, $x+$width/2,$y);
pdf_curveto($pdfobj, $x+$dx,$y, $x,$y+$dy, $x,$y+$height/2);
}
rod-php at thecomplex dot com (2002-10-01 10:15:22)
function pdf_ellipse_inscribed ($pdfobj,$x,$y,$width,$height) {
// Function to draw an ellipse inscribed in a rectangle
// described by lower left (x,y) with width and height.
pdf_moveto($pdfobj, $x,$y+$height/2);
pdf_curveto($pdfobj, $x,$y+$height/2,$x,$y+$height,$x+$width/2,$y+$height);
pdf_curveto($pdfobj, $x+$width/2,$y+$height,$x+$width,$y+$height,$x+$width,$y+$height/2);
pdf_curveto($pdfobj, $x+$width,$y+$height/2,$x+$width,$y,$x+$width/2,$y);
pdf_curveto($pdfobj, $x+$width/2,$y,$x,$y,$x,$y+$height/2);
}