drawing.h File Reference

#include <types.h>
#include <stdint.h>

Go to the source code of this file.

Macros
#define	GRAPHICS_WIDTH   160
#define	GRAPHICS_HEIGHT   144
#define	SOLID   0x00 /* Overwrites the existing pixels */
#define	OR   0x01 /* Performs a logical OR */
#define	XOR   0x02 /* Performs a logical XOR */
#define	AND   0x03 /* Performs a logical AND */
#define	WHITE   0
#define	LTGREY   1
#define	DKGREY   2
#define	BLACK   3
#define	M_NOFILL   0
#define	M_FILL   1
#define	SIGNED   1
#define	UNSIGNED   0

Functions
void	drawing_lcd (void)
void	gprint (char *str) NONBANKED
void	gprintln (int16_t number, int8_t radix, int8_t signed_value) NONBANKED
void	gprintn (int8_t number, int8_t radix, int8_t signed_value) NONBANKED
int8_t	gprintf (char *fmt,...) NONBANKED
void	plot (uint8_t x, uint8_t y, uint8_t colour, uint8_t mode) OLDCALL
void	plot_point (uint8_t x, uint8_t y) OLDCALL
void	switch_data (uint8_t x, uint8_t y, uint8_t *src, uint8_t *dst) OLDCALL
void	draw_image (uint8_t *data) OLDCALL
void	line (uint8_t x1, uint8_t y1, uint8_t x2, uint8_t y2) OLDCALL
void	box (uint8_t x1, uint8_t y1, uint8_t x2, uint8_t y2, uint8_t style) OLDCALL
void	circle (uint8_t x, uint8_t y, uint8_t radius, uint8_t style) OLDCALL
uint8_t	getpix (uint8_t x, uint8_t y) OLDCALL
void	wrtchr (char chr) OLDCALL
void	gotogxy (uint8_t x, uint8_t y) OLDCALL
void	color (uint8_t forecolor, uint8_t backcolor, uint8_t mode) OLDCALL

Detailed Description

All Points Addressable (APA) mode drawing library.

Drawing routines originally by Pascal Felber Legendary overhall by Jon Fuge : https://github.com/jf1452 Commenting by Michael Hope

Note: The standard text printf() and putchar() cannot be used in APA mode - use gprintf() and wrtchr() instead.

Note: Using drawing.h will cause it's custom LCD ISR (drawing_lcd) to be installed. This ISR handler changes the tile data source at start-of-frame and mid-frame so that 384 background tiles can be used instead of the typical 256.

To exit APA mode and remove the LCD ISR, use remove_LCD(drawing_lcd);

The valid coordinate ranges are from (x,y) 0,0 to 159,143. There is no built-in clipping, so drawing outside valid coordinates will likely produce undesired results (wrapping/etc).

---

Important note for the drawing API :

The Game Boy graphics hardware is not well suited to frame-buffer style graphics such as the kind provided in drawing.h. Due to that, most drawing functions (rectangles, circles, etc) will be slow . When possible it's much faster and more efficient to work with the tiles and tile maps that the Game Boy hardware is built around.

Macro Definition Documentation

GRAPHICS_WIDTH

#define GRAPHICS_WIDTH   160

Size of the screen in pixels

GRAPHICS_HEIGHT

#define GRAPHICS_HEIGHT   144

SOLID

#define SOLID   0x00 /* Overwrites the existing pixels */

OR

#define OR   0x01 /* Performs a logical OR */

XOR

#define XOR   0x02 /* Performs a logical XOR */

AND

#define AND   0x03 /* Performs a logical AND */

WHITE

#define WHITE   0

Possible drawing colours

LTGREY

#define LTGREY   1

DKGREY

#define DKGREY   2

BLACK

#define BLACK   3

M_NOFILL

#define M_NOFILL   0

Possible fill styles for box() and circle()

M_FILL

#define M_FILL   1

SIGNED

#define SIGNED   1

Possible values for signed_value in gprintln() and gprintn()

UNSIGNED

#define UNSIGNED   0

Function Documentation

drawing_lcd()

void drawing_lcd

(

void

)

APA LCD interrupt handler

gprint()

void gprint

(

char *

str

)

Print the string 'str' with no interpretation

See also

gotogxy()

gprintln()

void gprintln	(	int16_t	number,
		int8_t	radix,
		int8_t	signed_value
	)

Print 16 bit number in radix (base) in the default font at the current text position.

Parameters

number	number to print
radix	radix (base) to print with
signed_value	should be set to SIGNED or UNSIGNED depending on whether the number is signed or not

The current position is advanced by the numer of characters printed.

See also

gotogxy()

gprintn()

void gprintn	(	int8_t	number,
		int8_t	radix,
		int8_t	signed_value
	)

Print 8 bit number in radix (base) in the default font at the current text position.

See also

gprintln(), gotogxy()

gprintf()

int8_t gprintf	(	char *	fmt,
			...
	)

Print the string and arguments given by fmt with arguments __...__

Parameters

fmt	The format string as per printf
...	params

Currently supported:

• %c (character)
• %u (int)
• %d (int8_t)
• %o (int8_t as octal)
• %x (int8_t as hex)
• %s (string)

Returns

Returns the number of items printed, or -1 if there was an error.

See also

gotogxy()

plot()

void plot	(	uint8_t	x,
		uint8_t	y,
		uint8_t	colour,
		uint8_t	mode
	)

Old style plot - try plot_point()

plot_point()

void plot_point	(	uint8_t	x,
		uint8_t	y
	)

Plot a point in the current drawing mode and colour at x,y

switch_data()

void switch_data	(	uint8_t	x,
		uint8_t	y,
		uint8_t *	src,
		uint8_t *	dst
	)

Exchanges the tile on screen at x,y with the tile pointed by src, original tile is saved in dst. Both src and dst may be NULL - saving or copying to screen is not performed in this case.

draw_image()

void draw_image

(

uint8_t *

data

)

Draw a full screen image at data

line()

void line	(	uint8_t	x1,
		uint8_t	y1,
		uint8_t	x2,
		uint8_t	y2
	)

Draw a line in the current drawing mode and colour from x1,y1 to x2,y2

box()

void box	(	uint8_t	x1,
		uint8_t	y1,
		uint8_t	x2,
		uint8_t	y2,
		uint8_t	style
	)

Draw a box (rectangle) with corners x1,y1 and x2,y2 using fill mode style (one of NOFILL or FILL)

circle()

void circle	(	uint8_t	x,
		uint8_t	y,
		uint8_t	radius,
		uint8_t	style
	)

Draw a circle with centre at x,y and radius using fill mode style (one of NOFILL or FILL)

getpix()

uint8_t getpix	(	uint8_t	x,
		uint8_t	y
	)

Returns the current colour of the pixel at x,y

wrtchr()

void wrtchr

(

char

chr

)

Prints the character chr in the default font at the current text position.

The current position is advanced by 1 after the character is printed.

See also

gotogxy()

gotogxy()

void gotogxy	(	uint8_t	x,
		uint8_t	y
	)

Sets the current text position to x,y.

Note: x and y have units of tiles (8 pixels per unit)

See also

wrtchr()

color()

void color	(	uint8_t	forecolor,
		uint8_t	backcolor,
		uint8_t	mode
	)

Set the current forecolor colour, backcolor colour, and draw mode

Parameters

forecolor	The primary drawing color (outlines of rectangles with box(), letter color with gprintf(), etc).
backcolor	Secondary or background color where applicable (fill color of rectangles with box() when M_FILL is specifed, background color of text with gprintf(), etc).
mode	Drawing style to use. Several settings are available SOLID, OR, XOR, AND.

In order to completely overwrite existing pixels use SOLID for mode