Q3CanvasSprite Class Reference
[Qt3Support module]

Detailed Description

The Q3CanvasSprite class provides an animated canvas item on a Q3Canvas.

A canvas sprite is an object which can contain any number of images (referred to as frames), only one of which is current, i.e. displayed, at any one time. The images can be passed in the constructor or set or changed later with setSequence(). If you subclass Q3CanvasSprite you can change the frame that is displayed periodically, e.g. whenever Q3CanvasItem::advance(1) is called to create the effect of animation.

The current frame can be set with setFrame() or with move(). The number of frames available is given by frameCount(). The bounding rectangle of the current frame is returned by boundingRect().

The current frame's image can be retrieved with image(); use imageAdvanced() to retrieve the image for the frame that will be shown after advance(1) is called. Use the image() overload passing it an integer index to retrieve a particular image from the list of frames.

Use width() and height() to retrieve the dimensions of the current frame.

Use leftEdge() and rightEdge() to retrieve the current frame's left-hand and right-hand x-coordinates respectively. Use bottomEdge() and topEdge() to retrieve the current frame's bottom and top y-coordinates respectively. These functions have an overload which will accept an integer frame number to retrieve the coordinates of a particular frame.

Q3CanvasSprite draws very quickly, at the expense of memory.

The current frame's image can be drawn on a painter with draw().

Like any other canvas item, canvas sprites can be moved with move() which sets the x and y coordinates and the frame number, as well as with Q3CanvasItem::move() and Q3CanvasItem::moveBy(), or by setting coordinates with Q3CanvasItem::setX(), Q3CanvasItem::setY() and Q3CanvasItem::setZ().

See also QtCanvas and Porting to Graphics View.

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