video_gr

Functions
void *	vg_init (unsigned short mode)
	Initializes the video module in graphics mode.
int	vg_fill (unsigned long color)
	Fills the screen with the input color.
int	vg_set_pixel (unsigned long x, unsigned long y, unsigned long color)
	Sets input pixel with input color.
long	vg_get_pixel (unsigned long x, unsigned long y)
	Returns the color of the input pixel.
int	vg_draw_line (unsigned long xi, unsigned long yi, unsigned long xf, unsigned long yf, unsigned long color)
	Draw line segment with specifed end points and color.
int	vg_exit (void)
	Returns to default Minix 3 text mode (0x03: 25 x 80, 16 colors)

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Detailed Description

Functions for outputing data to screen in graphics mode

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Function Documentation

void* vg_init

(

unsigned short

mode

)

Initializes the video module in graphics mode.

Uses the VBE INT 0x10 interface to set the desired graphics mode, maps VRAM to the process' address space and initializes static global variables with the resolution of the screen, and the number of colors

Parameters:

mode	16-bit VBE mode to set

Returns:

Virtual address VRAM was mapped to. NULL, upon failure.

int vg_fill

(

unsigned long

color

)

Fills the screen with the input color.

Parameters:

color

color to fill the screen with

Returns:

0 on success, non-zero upon failure

int vg_set_pixel	(	unsigned long	x,
		unsigned long	y,
		unsigned long	color
	)

Sets input pixel with input color.

Sets the color of the pixel at the specified position to the input value, by writing to the corresponding location in VRAM

Parameters:

x	horizontal coordinate, starts at 0 (leftmost pixel)
y	vertical coordinate, starts at 0 (top pixel)
color	color to set the pixel

Returns:

0 on success, non-zero otherwise

long vg_get_pixel	(	unsigned long	x,
		unsigned long	y
	)

Returns the color of the input pixel.

Returns the color of the pixel at the specified position, by reading to the corresponding location in VRAM

Parameters:

x	horizontal coordinate, starts at 0 (leftmost pixel)
y	vertical coordinate, starts at 0 (top pixel)

Returns:

color of the pixel at coordinates (x,y), or -1 if some input argument is not valid

int vg_draw_line	(	unsigned long	xi,
		unsigned long	yi,
		unsigned long	xf,
		unsigned long	yf,
		unsigned long	color
	)

Draw line segment with specifed end points and color.

Draws a line segment with the specified end points and the input color, by writing to VRAM

Parameters:

xi	horizontal coordinate of "first" endpoint, starts at 0 (leftmost pixel)
yi	vertical coordinate of "first" endpoint, starts at 0 (top pixel)
xf	horizontal coordinate of "last" endpoint, starts at 0 (leftmost pixel)
yf	vertical coordinate of "last" endpoint, starts at 0 (top pixel)
color	color of the line segment to draw

Returns:

0 upon success, non-zero upon failure

int vg_exit

(

void

)

Returns to default Minix 3 text mode (0x03: 25 x 80, 16 colors)

Returns:

0 upon success, non-zero upon failure