Motorola C450 User Manual

8
Gaming API and Sound

calling

setAnimatedTileImage(-2, 2);

, cells (0,0) and (0,1) will then be drawn

with the image of static Tile 2.

Using Sprites

In addition to being a grid of cells, a

Playfield

can have a set of associated

Sprites

(see 0 item). When the

PlayField

is drawn, the grid is considered to have depth 0.

Therefore,

Sprites

below the grid (

Sprites

with

Sprite.getDepth() < 0

)

are drawn first. Then all cells in the grid are drawn. Then all the

Sprites

above the grid

(

Sprite.getDepth() >= 0

) are drawn. The

Sprites

are drawn according to

their location and visibility status as defined in the

Sprite

class. The location of

Sprites

is relative to the top-left corner of the

PlayField

Defining View Windows

A view window onto the

PlayField

can be defined using the method

setViewWindow()

. This defines the area of the

PlayField

that will be drawn by

the

draw()

method. The default viewing window onto a

PlayField

(at construction

time) is the entire area of the

PlayField

PlayField Constructor

The

PlayField

class defines the following constructors:

PlayField (int columns, int rows, Image img, int tWidth, int tHeight) throws

NullPointerException, IllegalArgumentException - Creates a new PlayField with a tile
set. The parameter are the following

−

columns

- width of the PlayField in number of cells;

−

rows

- height of the PlayField in number of cells;

−

img

- Image to use for creating tiles;

−

tWidth

- width, in pixels, of the individual tiles;

−

tHeight

- height, in pixels, of the individual tiles.

It creates a new

PlayField

rows

cells high and

columns

cells wide. The static

tile set for the PlayField will be created from subsections of the image passed in. The

PlayField

grid is initially filled with empty cells (tile 0 - a reserved tile and

represents an empty square) and laying out tiles must be accomplished through the

use of other methods in the class. The creation of the static tile set follows these
standards:

Tiles must be equally sized, all being of the tile width (

tWidth

) and height

(

tHeight

) defined in the constructor parameters. They may be laid out in the image

horizontally, vertically, or as a grid. The width of the source image must be an integer