totalcross.game

Class TextRenderer

java.lang.Object

totalcross.game.TextRenderer

public class TextRenderer
extends java.lang.Object

A game specific, fast text renderer (no memory allocs during runtime).
Important! The text displayed must not reach the screen limits!

It renders the text and the digits in image buffers and the display functions of this class just copies the image buffers back to the graphic context.

The text buffer is copied first, then the configured amount of digits of the optional integer are copied next to the text with leading zeros.

This class can be used to display game information such as scores, levels, etc.

You can find a complete game API sample named 'Scape' in the TotalCross examples folder.
Here is some sample code:

 import totalcross.game.*;
 import totalcross.util.props.*;
 ...

 public class Ping extends GameEngine {

   // 2 text renderers to quickly display level and score values

   private TextRenderer levelRenderer;
   private TextRenderer scoreRenderer;

 //---------------------------------------------------------
 // overload the API's game init event.
 // this function is called when the game is launched.
 //---------------------------------------------------------

 public void onGameInit() {

     // create two text renderers, one for the 'level' and one for the 'score'
     // we use the current font, the text should be black on the game background

     // level display has 2 digits: max value is 99

     levelRenderer=createTextRenderer(getFont(),Color.BLACK,"level:",2);

     // score display has 5 digits: max value is 99999

     scoreRenderer=createTextRenderer(getFont(),Color.BLACK,"score:",5);
   }

 //---------------------------------------------------------
 // overload TotalCross' onPaint function.
 //---------------------------------------------------------

 public void onPaint(Graphics gfx) {

   ...
   if (gameIsRunning) {  // game engine's running state

     ...
     // display the game level & score, both enable transparency

     levelRenderer.display(15,2,level,true);
     scoreRenderer.display(80,2,score,true);
     ...
   }
   ...
 }

Field Summary

Fields

Modifier and Type	Field and Description
protected int	fmH height in pixels of the drawing (= font metrics height).
protected int	textWidth width in pixels of the text.
protected boolean	zeroPadding enable left zero padding.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	TextRenderer(Font font, int foreColor, int backColor, java.lang.String text, int maxDigits) Creates a text renderer with the given parameters.
protected	TextRenderer(Font font, int foreColor, int backColor, java.lang.String text, int maxDigits, boolean zeroPadding) Creates a text renderer with the given parameters.

Method Summary

Modifier and Type	Method and Description
void	display(int x, int y, boolean transparent) Display a text rendering.
void	display(int x, int y, int value) Display a text rendering.
int	getHeight() Returns the height of the current font
int	getWidth() Returns the maximum width of the text plus the number of digits

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

fmH

protected int fmH

height in pixels of the drawing (= font metrics height).

textWidth

protected int textWidth

width in pixels of the text.

zeroPadding

protected boolean zeroPadding

enable left zero padding.

Constructor Detail

TextRenderer

protected TextRenderer(Font font,
                       int foreColor,
                       int backColor,
                       java.lang.String text,
                       int maxDigits,
                       boolean zeroPadding)
                throws ImageException

Creates a text renderer with the given parameters.

Parameters:

font - to use

foreColor - text foreground color

backColor - text background color

text - to be displayed before the digits (or null if none)

maxDigits - the number of digits to display. E.g.: 4 means the max value shown will be 9999.

zeroPadding - pad with leading zeros.

Throws:

ImageException

TextRenderer

protected TextRenderer(Font font,
                       int foreColor,
                       int backColor,
                       java.lang.String text,
                       int maxDigits)
                throws ImageException

Creates a text renderer with the given parameters.

Parameters:

font - to use

foreColor - text foreground color

backColor - text background color

text - to be displayed before the digits (or null if none)

maxDigits - the number of digits to display. E.g.: 4 means the max value shown will be 9999.

Throws:

ImageException

Method Detail

display

public void display(int x,
                    int y,
                    boolean transparent)

Display a text rendering. This function just draws the text to the GameEngineMainWindow at the specified x,y position.

Parameters:

x - position.

y - position.

transparent - should the background be preserved.

display

public void display(int x,
                    int y,
                    int value)

Display a text rendering. This function just copies back the image buffer of the text to the GameEngineMainWindow at the specified x,y position and displays the integer value next to the text by using pre-rendered digit image buffers.

Parameters:

x - position.

y - position.

value - positive integer value to draw next to the text.

getWidth

public int getWidth()

Returns the maximum width of the text plus the number of digits

getHeight

public int getHeight()

Returns the height of the current font