de.frame4j.graf

Class DisplayPattern

java.lang.Object

de.frame4j.graf.DisplayPattern

@MinDoc(copyright="Copyright 2000 - 2009, 2019  A. Weinert",
        author="Albrecht Weinert",
        version="V.65",
        lastModified="3.06.2024",
        usage="start as Java application (-? for help)",
        purpose="supports application with patterns for a dot matrix display")
public class DisplayPattern
extends Object

Plain patterns for a matrix display.

This class features the pattern for a 5 * 8 dot matrix display, like those used in the class. The character set is best described by "ISO 8859-1 + a few Unicode specials and Greeks". Start this class as application for a full display list (as starlet/asterisk images).

For the simplest possible display of printable characters without good small letters going below underline 5 * 8 dots it is sufficient.

Every point's state is represented by a byte value; the meaning / code is:

Value	Meaning	Colour
0	Off	background
1	On	foreground
2..127	Not off	Not used in this class. application specific. See get(char, byte)

Copyright 2000 - 2003, 2019 Albrecht Weinert

Field Summary

Fields

Modifier and Type	Field and Description
static byte[][]	SPACE Pattern for space.
static byte[][]	UNDEF Pattern for Undefined.
static int	X_DOTS Number of points, X direction, horizontal.
static int	Y_DOTS Number of points, Y direction, vertical.

Method Summary

Modifier and Type	Method and Description
static byte[][]	get(char c) Get the patter by character (code).
static byte[][]	get(char c, byte onValue) Fetch the pattern for a character.
static void	main(String[] a) Output all defined character pattern.

Methods inherited from class java.lang.Object

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

Field Detail

X_DOTS

public static final int X_DOTS

Number of points, X direction, horizontal.

Value: 5

See Also:

Constant Field Values

Y_DOTS

public static final int Y_DOTS

Number of points, Y direction, vertical.

Value: 8

See Also:

Constant Field Values

SPACE

public static final byte[][] SPACE

Pattern for space.

Value: length 0 (since V00.03, 13.06.01)

UNDEF

public static final byte[][] UNDEF

Pattern for Undefined.

Effect is like blank.

Value: one null (since V00.03, 18.06.01)

Method Detail

get

public static byte[][] get(char c)

Get the patter by character (code).

Returned is a "two dimensional" 8 * 5 (or shorter; see hint) array of byte for the character

As far / as good as displayable as 5 * 8 dots, pattern for character codes 00 to FF (according to Unicode or ISO8859-1 in this range) are available as well as some Greek letters (Unicode 0390 to 03CF) and some extra characters as the Euro sign (not quite good in 5 * 8), for example.

Unimplemented or non displayable characters (as control characters) return UNDEF, that as SPACE would be displayed as blank, according the substitution rules..

Substitution rules

1. Lines that end in one or more zeros ((byte) 0) for off may be shortened.
2. Instead of a line, containing just five zeros ((byte) 0) may stand a null (byte[])null).
3. If the pattern ends in one or more such empty or blank lines, the line array (first index) might be shortened accordingly, down to length zero but not be (byte[][])null.

Warning: This method returns references to the internal pattern arrays of type byte[] and byte[][]. Defensive copies would be an immense waste in the highly dynamic display applications. Do not modify!.
If modifications are necessary (or possible) use get(char, byte) instead, which returns a new (full) 5 * 8 byte[][] dot array every time.

Parameters:

c - the character (Unicode number)

Returns:

the pattern or UNDEF

get

public static byte[][] get(char c,
                           byte onValue)

Fetch the pattern for a character.

Returned is a new "two dimensional" 8 * 5 byte array for the character c.

Matrix dots to be on do display the given character, are set to the onValue if that is in the range 2..127 or 1. Off dots get the value 0.

Hint: This method returns (every time) a new array. This may be modified opposed to the array returned by get(char c), which has quite similar results as get(c, 1). Both methods have the same parameter range for c.

main

public static void main(String[] a)

Output all defined character pattern.

The output is just on normal output (System.out) and may only by > written to a File.