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QRadialGradient Class Reference
^{^{[QtGui module]}}

The QRadialGradient class is used in combination with QBrush to specify a radial gradient brush. More...

Inherits QGradient.

Methods

__init__ (self)
__init__ (self, QPointF center, float radius, QPointF focalPoint)
__init__ (self, QPointF center, float centerRadius, QPointF focalPoint, float focalRadius)
__init__ (self, QPointF center, float radius)
__init__ (self, float cx, float cy, float radius, float fx, float fy)
__init__ (self, float cx, float cy, float centerRadius, float fx, float fy, float focalRadius)
__init__ (self, float cx, float cy, float radius)
__init__ (self, QRadialGradient)
QPointF center (self)
float centerRadius (self)
QPointF focalPoint (self)
float focalRadius (self)
float radius (self)
setCenter (self, QPointF center)
setCenter (self, float x, float y)
setCenterRadius (self, float radius)
setFocalPoint (self, QPointF focalPoint)
setFocalPoint (self, float x, float y)
setFocalRadius (self, float radius)
setRadius (self, float radius)

Detailed Description

The QRadialGradient class is used in combination with QBrush to specify a radial gradient brush.

Qt supports both simple and extended radial gradients.

Simple radial gradients interpolate colors between a focal point and end points on a circle surrounding it. Extended radial gradients interpolate colors between a focal circle and a center circle. Points outside the cone defined by the two circles will be transparent. For simple radial gradients the focal point is adjusted to lie inside the center circle, whereas the focal point can have any position in an extended radial gradient.

Outside the end points the gradient is either padded, reflected or repeated depending on the currently set spread method:


PadSpread (default)	ReflectSpread	RepeatSpread

The colors in a gradient is defined using stop points of the QGradientStop type, i.e. a position and a color. Use the QGradient.setColorAt() or the QGradient.setStops() function to define the stop points. It is the gradient's complete set of stop points that describes how the gradient area should be filled. If no stop points have been specified, a gradient of black at 0 to white at 1 is used.

In addition to the functions inherited from QGradient, the QRadialGradient class provides the center(), focalPoint() and radius() functions returning the gradient's center, focal point and radius respectively.

Method Documentation

QRadialGradient.init (self)

Constructs a simple radial gradient with the center and focal point at (0, 0) with a radius of 1.

QRadialGradient.init (self, QPointF center, float radius, QPointF focalPoint)

Constructs a simple radial gradient with the given center, radius and focalPoint.

Note: If the given focal point is outside the circle defined by the center point and radius, it will be re-adjusted to lie at a point on the circle where it intersects with the line from center to focalPoint.

See also QGradient.setColorAt() and QGradient.setStops().

QRadialGradient.init (self, QPointF center, float centerRadius, QPointF focalPoint, float focalRadius)

Constructs a simple radial gradient with the given center (cx, cy), radius and focal point (fx, fy).

Note: If the given focal point is outside the circle defined by the center (cx, cy) and the radius it will be re-adjusted to the intersection between the line from the center to the focal point and the circle.

See also QGradient.setColorAt() and QGradient.setStops().