CairoContext::arcNegative
cairo_arc_negative
(PECL cairo >= 0.1.0)
CairoContext::arcNegative -- cairo_arc_negative — Adds a negative arc
Описание
Объектно-ориентированный стиль (method):
$x
, float $y
, float $radius
, float $angle1
, float $angle2
) : voidПроцедурный стиль:
$context
, float $x
, float $y
, float $radius
, float $angle1
, float $angle2
) : void
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.
Список параметров
-
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
Возвращаемые значения
Эта функция не возвращает значения после выполнения.
Примеры
Пример #1 Объектно-ориентированный стиль
<?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');
?>
Пример #2 Процедурный стиль
<?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');
?>