=head1 NAME
Term::Graille - Graphical Display in the terminal using UTF8 Braille characters
=head1 SYNOPSIS
my $canvas = Term::Graille->new(
width => 72, # pixel width
height => 64, # pixel height
top=>3, # row position in terminal (optional,defaults to 1)
left=>10, # column position (optional,defaults to 1)
borderStyle => "double", #
);
=head1 DESCRIPTION
Inspired by Drawille by asciimoo, which has many variants (including
a perl variant Term::Drawille by RHOELZ), this is a clone with a few
extras. The goal is to achieve performance and features. with built-in
turtle-like graphics, line and curve drawing (Algorithm::Line::Bresenham),
scrolling, border setting, and more in development.
=begin html
=end html
=head1 FUNCTIONS
=cut
=head3 Cnew(%params)>
Creates a new canavas; params are
C The pixel width, required C the pixel height, required,
C terminal row (optional,default 1) C terminal column (
optional,default 1) C border type (optional,one of 'simple',
'double', 'thin', 'thick' or 'shadow') C border colour (
optional), C Title text for top border,(optional) C
Title colour (optional)
=cut
=head3 C<$canvas-Edraw()> , C<$canvas-Edraw($row, $column)>
Draws the canvas to the terminal window. Optional row and column
parameters may be passed to position the displayed canvas. If
borderStyle is specified, the border is drawn, If title is specified
this is added to the top border
=cut
=head3 C<$canvas-Eas_string()>
Returns the string containing the canvas of utf8 braille symbols, rows
being separated by newline.
=cut
=head3 C<$canvas-Eset($x,$y,$pixelValue)>
Sets a particular pixel on (default if C<$pixelValue> not sent) or off.
=cut
=head3 C<$canvas-Eunset($x,$y)>
Sets the pixel value at C<$x,$y> to blank
=cut
=head3 C<$canvas-Epixel($x,$y)>
Gets the pixel value at C<$x,$y>
=cut
=head3 C<$canvas-Eclear()>
Re-initialises the canvas with blank braille characters
=cut
=head3 C<$canvas-Eline($x1,$y1,$x2,$y2,$value)>
Uses Algorithm::Line::Bresenham to draw a line from C<$x1,$y1> to C<$x2,$y2>.
The optional value C<$value> sets or unsets the pixels
=cut
=head3 C<$canvas-Ecircle($x1,$y1,$radius,$value)>
Uses Algorithm::Line::Bresenham to draw a circle centered at C<$x1,$y1>
with radius C<$radius> to C<$x2,$y2>.
The optional value C<$value> sets or unsets the pixels
=cut
=head3 C<$canvas-Eellipse_rect($x1,$y1,$x2,$y2,$value)>
Uses Algorithm::Line::Bresenham to draw a rectangular ellipse, (an
ellipse bounded by a rectangle defined by C<$x1,$y1,$x2,$y2>).
The optional value C<$value> sets or unsets the pixels
=cut
=head3 C<$canvas-Equad_bezier($x1,$y1,$x2,$y2,$x3,$y3,$value)>
Uses Algorithm::Line::Bresenham to draw a quadratic bezier, defined by
end points C<$x1,$y1,$x3,$y3>) and control point C<$x2,$y2>.
The optional value C<$value> sets or unsets the pixels
=cut
=head3 C<$canvas-Epolyline($x1,$y1,....,$xn,$yn,$value)>
Uses Algorithm::Line::Bresenham to draw a poly line, form a
sequences of points.
The optional value C<$value> sets or unsets the pixels
=cut
=head2 Character Level Functions;
=head3 C<$canvas-Escroll($direction,$wrap)>
Scrolls in C<$direction>. $direction may be
"l", "left", "r","right", "u","up","d", "down".
Beacuse of the use of Braille characters, up/down scrolling is 4 pixels
at a time, whereas left right scrolling is 2 pixels at a time. If
C<$wrap> is a true value, the screen wraps around.
=cut
=head3 C<$canvas-EblockBlit($block,$gridX, $gridY)>
Allows blitting a 2d arrays to a grid location in the canvas. Useful for
printing using a Graille font.
=cut
=head3 C<$canvas-EexportCanvas($filename)> , C<$canvas-EimportCanvas($filename)>
This allows the loading and unloading of a canvas from a file. There is
no checking of the dimension of the canvas being imported at the moment
=cut
=head2 Enhancements
=head3 C<$canvas-Elogo($script)>
Interface to Graille's built in Turtle interpreter.
A string is taken and split by senicolons or newlines into instructions.
The instructions are trimmed, and split by the first space character into
command and parameters. Very simple in other words. No syntax checking
is done
C<"fd distance"> pen moves forward a certain distance.
C<"lt angle">, C<"rt angle"> turns left or right.
C<"bk distance"> pen moves back a certain distance.
C<"pu">, C<"pd"> Pen is up or down, up means no drawing takes place,
and down means the turtle draws as it moves.
C<"dir"> set the direction at a specific angle in dgrees,
with 0 being directly left.
C<"mv">moves pen to specific coordinates without drawing.
C<"ce"> centers the turtle in the middle of a canvas
C<"sp"> allows animated drawing by specifiying the the number
of centiseconds between instructions
=cut
=head3 Exported Routines
Graille exports some functions for additional console graphical manipulation
This includes drawing of borders, printing characters at specific locations
in the terminal window, and colouring the characters, clearing the screen, etc.
printAt($row,$column,@textRows);
Prints text sent as a scalar, a list of scalars or a reference to list
of scalars, at a specific location on the screen. Lists are printed
from the same column but increasing row positions.
border($top,$left,$bottom,$right,$style,$colour);
Draws a border box.
paint($txt,$fmt)
Paints text the colour and background specified, $text may be a string, or ref
to a list of strings. This is combined with C abouve
clearScreen()
Guess what? clears the enire screen. This is different from C<$canvas-Eclear()>
which clears the Graille canvas.
block2braille($block)
Given a block of binary data (a 2D Array ref of 8-bit data), return a
corresponding 2d Array ref of braille blocks. This is handy to convert,
say, binary font data tinto Braille blocks for blittting into the canvas;
pixelAt($block,$px,$py)
Given a binary block of data e.g. a font or a sprite offered as a 2D Array ref
find the pixel value at a certain coordinate in that block.
=cut
=head1 AUTHOR
Saif Ahmed
=head1 LICENSE
Artistic
=head1 INSTALLATION
Manual install:
$ perl Makefile.PL
$ make
$ make install
=cut