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# CairoContext::arcNegative

# cairo_arc_negative

(PECL cairo >= 0.1.0)

CairoContext::arcNegative -- cairo_arc_negative — Adds a negative arc

### Description

Object oriented style (method):

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

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() for more details. This function differs only in the direction of the arc between the two angles.

### Liste de paramètres

`context`

  A valid CairoContext object

`x`

  double x position

`y`

  double y position

`radius`

  The radius of the desired negative arc

`angle1`

  Start angle of the arc

`angle2`

  End angle of the arc

### Valeurs de retour

Aucune valeur n'est retournée.

### Exemples

Exemple #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');
?>`

Exemple #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');
?>`

### Voir aussi

- CairoContext::arc - Adds a circular arc

CairoContext::arc
CairoContext::clip
CairoContext
PHP Manual