1 /*

     2 * Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:

    15 *

    16 */

    17 package javax.microedition.lcdui.game;

    18 

    19 import javax.microedition.lcdui.Graphics;

    20 import javax.microedition.lcdui.Image;

    21 

    22 /**

    23  * LCDUI Layer class.

    24  */

    25 public abstract class Layer

    26 {

    27 

    28     int x;

    29     int y;

    30     boolean visible;

    31 

    32     Image tileImage;

    33 

    34     int tileWidth;

    35     int tileHeight;

    36 

    37     int tileCount;

    38     int tileColumns;

    39 

    40     /**

    41      * Package level constructor prevents Layer being subclassed. This is

    42      * consistent with the MIDP 2.0 RI.

    43      */

    44     Layer(Image tileImage, int frameWidth, int frameHeight)

    45     {

    46         visible = true;

    47         setTileImage(tileImage, frameWidth, frameHeight);

    48     }

    49 

    50     Layer(Layer from)

    51     {

    52         x = from.x;

    53         y = from.y;

    54         visible = from.visible;

    55         tileImage = from.tileImage;

    56         tileWidth = from.tileWidth;

    57         tileHeight = from.tileHeight;

    58         tileCount = from.tileCount;

    59         tileColumns = from.tileColumns;

    60     }

    61 

    62     public void setPosition(int x, int y)

    63     {

    64         this.x = x;

    65         this.y = y;

    66     }

    67 

    68     public void move(int deltaX, int deltaY)

    69     {

    70         x += deltaX;

    71         y += deltaY;

    72     }

    73 

    74     public final int getX()

    75     {

    76         return x;

    77     }

    78 

    79     public final int getY()

    80     {

    81         return y;

    82     }

    83 

    84     public final int getWidth()

    85     {

    86         return getLayerWidth();

    87     }

    88 

    89     public final int getHeight()

    90     {

    91         return getLayerHeight();

    92     }

    93 

    94     public void setVisible(boolean visible)

    95     {

    96         this.visible = visible;

    97     }

    98 

    99     public final boolean isVisible()

   100     {

   101         return visible;

   102     }

   103 

   104     public abstract void paint(Graphics graphics);

   105 

   106     abstract int getLayerWidth();

   107 

   108     abstract int getLayerHeight();

   109 

   110     /**

   111      * Set the source image and tile size. checks that the image is completely

   112      * tiled. computes the tile count.

   113      */

   114     void setTileImage(Image tileImage, int tileWidth, int tileHeight)

   115     {

   116         if(tileWidth > 0 && tileHeight > 0)

   117         {

   118             final int imageWidth = tileImage.getWidth();

   119             final int imageHeight = tileImage.getHeight();

   120 

   121             int rows = imageHeight / tileHeight;

   122             int cols = imageWidth / tileWidth;

   123 

   124             int totalHeight = rows * tileHeight;

   125             int totalWidth = cols * tileWidth;

   126 

   127             if(totalHeight == imageHeight && totalWidth == imageWidth)

   128             {

   129                 this.tileImage = tileImage;

   130                 this.tileWidth = tileWidth;

   131                 this.tileHeight = tileHeight;

   132                 this.tileCount = rows * cols;

   133                 this.tileColumns = cols;

   134                 return;

   135             }

   136         }

   137         throw new IllegalArgumentException(

   138             MsgRepository.LAYER_EXCEPTION_INVALID_TILE_WIDTH_HEIGHT);

   139     }

   140 

   141     /**

   142      * Is Layer visible in Graphics clip region.

   143      */

   144     final boolean isVisible(Graphics graphics, int pX, int pY)

   145     {

   146         int x1 = x + pX;

   147         int y1 = y + pY;

   148         int x2 = x1 + getWidth();

   149         int y2 = y1 + getHeight();

   150         int clipX1 = graphics.getClipX();

   151         int clipY1 = graphics.getClipY();

   152         int clipX2 = clipX1 + graphics.getClipWidth();

   153         int clipY2 = clipY1 + graphics.getClipHeight();

   154 

   155         return !(clipX2 <= x1 || clipY2 <= y1 || clipX1 >= x2 || clipY1 >= y2);

   156     }

   157 

   158 }