gfx.cpp File Reference

#include "gfx.h"
#include "gridfont.h"

Functions
void	init_gfx ()
	init ASCII GFX More...
void	init_color ()
	init ASCII GFX color display More...
void	exit_gfx ()
	exit ASCII GFX More...
void	set_window (WINDOW *w)
	set the drawing window More...
void	use_color (int index)
	use indexed color pair for foreground/background colors of characters More...
void	use_attr_bold ()
	use attribute bold More...
void	use_attr_blink ()
	use attribute blink More...
void	use_attr_reverse ()
	use attribute reverse More...
void	use_attr_normal ()
	use attribute normal More...
void	draw_text (int y, int x, const char *format,...)
	draw a formatted text at position (x, y) More...
void	draw_sprite (int y, int x, const char *text)
	draw a sprite at barycenter position (x, y) More...
void	draw_area (int y, int x, int sy, int sx, const int *data)
	draw a screen area at top-left position (x, y) with size (sx, sy) More...
void	draw_grid_text (int y, int x, const char *text)
	draw a text string with grid font characters at top-left position (x, y) More...
void	draw_line (int y1, int x1, int y2, int x2, int ch, bool background)
	draw a line from position (x1, y1) to (x2, y2) More...
void	draw_frame (int y1, int x1, int y2, int x2, int ch)
	draw a frame from position (y1, x1) to (y2, x2) More...
void	draw_circle (int yc, int xc, int r, int ch, double aspect)
	draw a circle at center position (xc, yc) with radius r More...
void	draw_points (int yc, int xc, int y, int x, int ay, int ax, double aspect, int ch)
void	draw_ellipse (int yc, int xc, int ay, int ax, int ch, double aspect)
	draw a ellipse at center position (xc, yc) with principle axis ax and ay More...
int	peek (int y, int x)
	peek at location (y, x) and return the displayed character More...
int	get_keycode ()
	return wide keycode More...
void	cursor_keycode (int keycode, int *dx, unsigned int *dy)
	decode wide keycode More...
int *	convert_char_text (const char *text, int sx, int sy, int ch, bool interprete)
	helper for converting a text string into an ASCII data buffer More...
char *	get_string_buffer (int n)
	helper for allocating a temporarily used string buffer More...

Variables
static WINDOW *	W = NULL
static char *	string_buffer = NULL
static int	buffer_size = 0

Function Documentation

convert_char_text()

int* convert_char_text	(	const char *	text,
		int	sx,
		int	sy,
		int	ch = -1,
		bool	interprete = false
	)

helper for converting a text string into an ASCII data buffer

• "ch" is the character that represents transparent areas
• when "interprete" is enabled treat special characters as follows:
  • ^ as overscore
  • # as checker board
  • B as bold attribute
  • digits as color attributes
  • 0 to clear attributes

cursor_keycode()

void cursor_keycode	(	int	keycode,
		int *	dx,
		unsigned int *	dy
	)

decode wide keycode

• if a cursor event has been observed as a wide keycode, the function decodes it
• the function returns a corresponding direction vector (dx, dy) via call-by-reference

draw_area()

void draw_area	(	int	y,
		int	x,
		int	sy,
		int	sx,
		const int *	data
	)

draw a screen area at top-left position (x, y) with size (sx, sy)

• the data is made up from consecutive lines of characters

draw_circle()

void draw_circle	(	int	yc,
		int	xc,
		int	r,
		int	ch = -1,
		double	aspect = 2
	)

draw a circle at center position (xc, yc) with radius r

• Bresenham's circle drawing algorithm
• "ch" is the character used to draw the circle
  • by default graphical characters are used

draw_ellipse()

void draw_ellipse	(	int	yc,
		int	xc,
		int	ay,
		int	ax,
		int	ch = -1,
		double	aspect = 2
	)

draw a ellipse at center position (xc, yc) with principle axis ax and ay

• Bresenham's ellipse drawing algorithm
• "ch" is the character used to draw the ellipse
  • by default graphical characters are used

draw_frame()

void draw_frame	(	int	y1,
		int	x1,
		int	y2,
		int	x2,
		int	ch = -1
	)

draw a frame from position (y1, x1) to (y2, x2)

• "ch" is the character used to draw the frame
  • by default graphical characters are used

draw_grid_text()

void draw_grid_text	(	int	y,
		int	x,
		const char *	text
	)

draw a text string with grid font characters at top-left position (x, y)

• the grid font needs to be initialized beforehand via init_grid_font()
• the grid text is made up from consecutive text lines separated by \n

draw_line()

void draw_line	(	int	y1,
		int	x1,
		int	y2,
		int	x2,
		int	ch = -1,
		bool	background = false
	)

draw a line from position (x1, y1) to (x2, y2)

• symmetrified Bresenham algorithm
• "ch" is the character used to draw the line
  • by default graphical characters are used
• "background" makes the line appear in non-empty background areas only

draw_points()

void draw_points	(	int	yc,
		int	xc,
		int	y,
		int	x,
		int	ay,
		int	ax,
		double	aspect,
		int	ch
	)

draw_sprite()

void draw_sprite	(	int	y,
		int	x,
		const char *	text
	)

draw a sprite at barycenter position (x, y)

• the sprite text needs to be a string that is terminated by \0
• the sprite text is made up from consecutive text lines separated by \n
• if the sprite position is outside of the screen the text will wrap around

draw_text()

void draw_text	(	int	y,
		int	x,
		const char *	format,
			...
	)

draw a formatted text at position (x, y)

• non-printable characters like \n will be ignored

exit_gfx()

void exit_gfx

(

)

exit ASCII GFX

• close the standard screen of NCurses

get_keycode()

int get_keycode

(

)

return wide keycode

get_string_buffer()

char* get_string_buffer

(

int

n

)

helper for allocating a temporarily used string buffer

• provides a buffer for a string with at most n characters
• it allocates memory for the n characters plus the terminal nul character

init_color()

void init_color

(

)

init ASCII GFX color display

• default colors are white, red, green, blue with indices 1-4
• and composite colors yellow, cyan, magenta with indices 5-7
• plus special inverse and black colors with indices 8-9

init_gfx()

void init_gfx

(

)

init ASCII GFX

• setup the standard screen of NCurses
• the screen origin (0, 0) is at the top left corner

peek()

int peek	(	int	y,
		int	x
	)

peek at location (y, x) and return the displayed character

set_window()

void set_window

(

WINDOW *

w

)

set the drawing window

• by default the standard screen is used

use_attr_blink()

void use_attr_blink

(

)

use attribute blink

use_attr_bold()

void use_attr_bold

(

)

use attribute bold

use_attr_normal()

void use_attr_normal

(

)

use attribute normal

use_attr_reverse()

void use_attr_reverse

(

)

use attribute reverse

use_color()

void use_color

(

int

index = 1

)

use indexed color pair for foreground/background colors of characters

• colors need to be initialized beforehand via init_color()
• 1 = white/black
• 2 = red/black
• 3 = green/black
• 4 = blue/black
• 5 = yellow/black
• 6 = cyan/black
• 7 = magenta/black
• 8 = black/white
• 9 = black/black

Variable Documentation

buffer_size

int buffer_size = 0

static

string_buffer

char* string_buffer = NULL

static

W

WINDOW* W = NULL

static