CairoContext::arcNegative
cairo_arc_negative
(PECL cairo >= 0.1.0)
CairoContext::arcNegative -- cairo_arc_negative — Adds a negative arc
Descrierea
Stil obiect-orientat (method):
$x
, float $y
, float $radius
, float $angle1
, float $angle2
)Stil procedural:
$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.
Parametri
-
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
Valorile întoarse
Nu este întoarsă nici o valoare.
Exemple
Example #1 Stil obiect-orientat
<?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 Stil procedural
<?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');
?>
