Motorola C370 Manual Do Utilizador
Animation Frames
An animated
sprite
is created from an image divided into sections as described in the
constructor Sprite(Image, int, int). The individual sections of the image are considered the
raw frames of the
raw frames of the
Sprite
. The method getNumRawFrames returns the number of raw
frames.
Sprite Drawing
Sprites
can be drawn at anytime using the
draw(Graphics)
method. The sprite
will be drawn on the
Graphics
object, according to the current state information
maintained by the Sprite (i.e. position, frame, visibility). Some potential uses of Sprites
include:
•
Arbitrarily draw the Sprite on a
GameScreen
.
•
A Sprite can be added to a
PlayField
. Then PlayField.draw(Graphics, int, int) will
automatically draw all the Sprites associated with the
PlayField
.
•
draw(Graphics) could be called from the
paint()
method in a subclass of
Canvas
.
•
draw(Graphics) could be called at any time to draw the
Sprite
on a MIDP mutable
image. This is virtually identical to the first bullet, drawing on a
GameScreen
.
Only in the case where a set of Sprites are a part of a container object (i.e. where the
Sprite
is associated with a
PlayField
) is the depth information automatically
handled by the system. In other situations, managing the drawing order is the
responsibility of the developer.
Sprite Constructor
The
Sprite
class defines the following constructors:
•
public Sprite(Image img)
– Creates a new non-animated
Sprite
from an
Image
object. All animation operations on a non-animated Sprite behave as
if there is a single raw frame. At construction time, the
Sprite's
position will be set
to (0,0), the depth will be set to 0, and the Sprite will be visible. The Sprite shall
behave as if the image used in creation were cached. If a mutable image is used to
create the Sprite, the Sprite's appearance should not reflect changes to mutable
create the Sprite, the Sprite's appearance should not reflect changes to mutable
source image.
•
public Sprite(Image img, int fWidth, int fHeight)
–
Creates a new animated
Sprite
from an Image. The constructor parameters are
the following:
−
img - Image to use for Sprite;
−
fWidth - width, in pixels, of the individual raw frames;
−
fHeight - height, in pixels, of the individual raw frames.