QtCanvasPixmapArray Class Reference

The QtCanvasPixmapArray class provides an array of QtCanvasPixmaps. More...

#include <QtCanvasPixmapArray>

Public Functions


Detailed Description

The QtCanvasPixmapArray class provides an array of QtCanvasPixmaps.

This class is used by QtCanvasSprite to hold an array of pixmaps. It is used to implement animated sprites, i.e. images that change over time, with each pixmap in the array holding one frame.

Depending on the constructor you use you can load multiple pixmaps into the array either from a directory (specifying a wildcard pattern for the files), or from a list of QPixmaps. You can also read in a set of pixmaps after construction using readPixmaps().

Individual pixmaps can be set with setImage() and retrieved with image(). The number of pixmaps in the array is returned by count().

QtCanvasSprite uses an image's mask for collision detection. You can change this by reading in a separate set of image masks using readCollisionMasks().


Member Function Documentation

QtCanvasPixmapArray::QtCanvasPixmapArray ()

Constructs an invalid array (i.e. isValid() will return false). You must call readPixmaps() before being able to use this QtCanvasPixmapArray.

QtCanvasPixmapArray::QtCanvasPixmapArray ( const QString & datafilenamepattern, int fc = 0 )

Constructs a QtCanvasPixmapArray from files.

The fc parameter sets the number of frames to be loaded for this image.

If fc is not 0, datafilenamepattern should contain "%1", e.g. "foo%1.png". The actual filenames are formed by replacing the %1 with four-digit integers from 0 to (fc - 1), e.g. foo0000.png, foo0001.png, foo0002.png, etc.

If fc is 0, datafilenamepattern is asssumed to be a filename, and the image contained in this file will be loaded as the first (and only) frame.

If datafilenamepattern does not exist, is not readable, isn't an image, or some other error occurs, the array ends up empty and isValid() returns false.

QtCanvasPixmapArray::~QtCanvasPixmapArray ()

Destroys the pixmap array and all the pixmaps it contains.

uint QtCanvasPixmapArray::count () const

Returns the number of pixmaps in the array.

QtCanvasPixmap * QtCanvasPixmapArray::image ( int i ) const

Returns pixmap i in the array, if i is non-negative and less than than count(), and returns an unspecified value otherwise.

See also setImage().

bool QtCanvasPixmapArray::isValid () const

Returns true if the pixmap array is valid; otherwise returns false.

bool QtCanvasPixmapArray::readCollisionMasks ( const QString & filename )

Reads new collision masks for the array.

By default, QtCanvasSprite uses the image mask of a sprite to detect collisions. Use this function to set your own collision image masks.

If count() is 1 filename must specify a real filename to read the mask from. If count() is greater than 1, the filename must contain a "%1" that will get replaced by the number of the mask to be loaded, just like QtCanvasPixmapArray::readPixmaps().

All collision masks must be 1-bit images or this function call will fail.

If the file isn't readable, contains the wrong number of images, or there is some other error, this function will return false, and the array will be flagged as invalid; otherwise this function returns true.

See also isValid().

bool QtCanvasPixmapArray::readPixmaps ( const QString & filenamepattern, int fc = 0 )

Reads one or more pixmaps into the pixmap array.

If fc is not 0, filenamepattern should contain "%1", e.g. "foo%1.png". The actual filenames are formed by replacing the %1 with four-digit integers from 0 to (fc - 1), e.g. foo0000.png, foo0001.png, foo0002.png, etc.

If fc is 0, filenamepattern is asssumed to be a filename, and the image contained in this file will be loaded as the first (and only) frame.

If filenamepattern does not exist, is not readable, isn't an image, or some other error occurs, this function will return false, and isValid() will return false; otherwise this function will return true.

See also isValid().

void QtCanvasPixmapArray::setImage ( int i, QtCanvasPixmap * p )

Replaces the pixmap at index i with pixmap p.

The array takes ownership of p and will delete p when the array itself is deleted.

If i is beyond the end of the array the array is extended to at least i+1 elements, with elements count() to i-1 being initialized to 0.

See also image().


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