need help

CAIRO_ARC_NEGATIVE(3)							 1						     CAIRO_ARC_NEGATIVE(3)

CairoContext::arcNegative - Adds a negative arc

       Object oriented style (method):

SYNOPSIS

       public void CairoContext::arcNegative (float  $x, float	$y, float  $radius, float  $angle1, float  $angle2)

DESCRIPTION

       Procedural style:
       void cairo_arc_negative (CairoContext  $context, float  $x, float  $y, float  $radius, float  $angle1, float  $angle2)

	Adds  a  circular  arc	of  the  given $radius to the current path. The arc is centered at ($x, $y), begins at $angle1 and proceeds in the
       direction of decreasing angles to end at $angle2. If $angle2 is greater than $angle1 it will be progressively decreased by 2*M_PI until	it
       is  less  than  $angle1.  See  CairoContext::arc  or  cairo_arc(3) for more details. This function differs only in the direction of the arc
       between the two angles.

PARAMETERS

	      o $context
		- A valid CairoContext object

	      o $x
		- double x position

	      o $y
		- double y position

	      o $radius
		- The radius of the desired negative arc

	      o $angle1
		- Start angle of the arc

	      o $angle2
		- End angle of the arc

RETURN VALUES

	No value is returned.

EXAMPLES

       Example #1

	      Object oriented style

	      <?php

	      $s = new CairoImageSurface(CairoFormat::ARGB32, 100, 100);
	      $c = new CairoContext($s);

	      $c->setSourceRgb(0, 0, 0);
	      $c->paint();

	      $c->setLineWidth(1);
	      $c->setSourceRgb(1, 1, 1);

	      for ($r = 50; $r > 0; $r -= 10) {
	       $c->arcNegative(50, 50, $r, 2 * M_PI, 0);
	       $c->stroke();
	       $c->fill();
	      }

	      $s->writeToPng(dirname(__FILE__) . '/CairoContext__arcNegative.png');
	      ?>

       Example #2

	      Procedural style

	      <?php

	      $s = cairo_image_surface_create(CAIRO_SURFACE_TYPE_IMAGE, 100, 100);
	      $c = cairo_create($s);

	      cairo_set_source_rgb($c, 0, 0, 0);
	      cairo_paint($c);

	      cairo_set_source_rgb($c, 1, 1, 1);
	      cairo_set_line_width($c, 1);

	      for ($r = 50; $r > 0; $r -= 10) {
	       cairo_arc_negative($c, 50, 50, $r, 2 * M_PI, 0);
	       cairo_stroke($c);
	       cairo_fill($c);
	      }

	      cairo_surface_write_to_png($s, dirname(__FILE__) . '/cairo_arc_negative.png');
	      ?>

SEE ALSO

       CairoContext::arc.

PHP Documentation Group 												     CAIRO_ARC_NEGATIVE(3)