net.freeutils.scrollphat

Class FontConverter

java.lang.Object

net.freeutils.scrollphat.FontConverter

public class FontConverter
extends Object

Converts a standard TrueType (TTF) font, rendered at a given size, to the ledfont format used at runtime by the LEDFont class.

In order to conserve resources on resource-limited devices (such as the Raspberry Pi), this utility can be used manually during development to generate font files in the lightweight format used by LEDFont, which in turn can be used during runtime to render text using the font.

Note that most standard desktop fonts look terrible, and often illegible, when rendered at tiny sizes for which they were not designed. However, if you look around you can find a dozen or two fonts that were designed specifically for tiny sizes and will look good even in a target font height of e.g. 5 pixels. Some of these are categorized as pixel fonts.

You may need to try various point sizes, one at a time, until you find the one that looks best for your target font height in pixels. For example, several fonts look best when rendered at a size of 8 points and cropped to a target height of 5 pixels (due ascent/descent spaces, etc.)

Please check the licensing terms of the fonts you use. Most of them are free for personal use, and many are also free for commercial use, but you'll need to verify compliance on a case-by-case basis. If you create your own fonts, please consider sharing them freely as well!

The -d or -t command line arguments can be used to print the converted font glyphs to the console to quickly assess how it looks.

The font pixel data is currently stored using one byte per column, i.e. there is a font height limit of 8 pixels.

Constructor Summary

Constructors

Constructor and Description
FontConverter()

Method Summary

Modifier and Type	Method and Description
static LEDFont	convert(Font font, int height, int offset) Converts the given font to ledfont format written to a LEDFont.
static void	convert(Font font, int height, int offset, File out) Converts the given font to ledfont format written to a file.
static void	convertFromPython(File in, int height, File out) Converts a python script defining a font data structure to a LEDFont.
static Font	loadTTF(String filename) Loads a TrueType (TTF) font from file or resource as an AWT Font.
static void	main(String[] args) The main command-line utility entry point.
static LEDFont	parsePython(InputStream in, int height) Parses a python script defining a font data structure.

Methods inherited from class java.lang.Object

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

Constructor Detail

FontConverter

public FontConverter()

Method Detail

loadTTF

public static Font loadTTF(String filename)
                    throws IOException

Loads a TrueType (TTF) font from file or resource as an AWT Font.

Parameters:

filename - the file (or resource) name

Returns:

the font

Throws:

IOException - if an error occurs

convert

public static LEDFont convert(Font font,
                              int height,
                              int offset)
                       throws IOException

Converts the given font to ledfont format written to a LEDFont.

Parameters:

font - the AWT font to convert

height - the target height in pixels

offset - an offset by which all glyphs should be raised or lowered relative to the font baseline (this should usually be zero)

Returns:

the converted LEDFont

Throws:

IOException - if an error occurs

convert

public static void convert(Font font,
                           int height,
                           int offset,
                           File out)
                    throws IOException

Converts the given font to ledfont format written to a file.

Parameters:

font - the AWT font to convert

height - the target height in pixels

offset - an offset by which all glyphs should be raised or lowered relative to the font baseline (this can usually be left at zero)

out - the file to which the ledfont data is written

Throws:

IOException - if an error occurs

parsePython

public static LEDFont parsePython(InputStream in,
                                  int height)
                           throws IOException

Parses a python script defining a font data structure.

Parameters:

in - the input stream containing the python script

height - the font height

Returns:

the parsed LEDFont

Throws:

IOException - if an error occurs

convertFromPython

public static void convertFromPython(File in,
                                     int height,
                                     File out)
                              throws IOException

Converts a python script defining a font data structure to a LEDFont.

Parameters:

in - the input file containing the python script

height - the font height

out - the file to which the ledfont data is written

Throws:

IOException - if an error occurs

main

public static void main(String[] args)
                 throws IOException

The main command-line utility entry point.

Parameters:

args - the arguments

Throws:

IOException - if an error occurs