Shapes

Rounded rectangles, ellipses, dithered fills and in-place recolouring. More...

Functions
void	gfx_roundRect (int x, int y, int w, int h, int r, uint8_t c)
	Draws a rounded rectangle's 1-pixel outline.
void	gfx_fillRoundRect (int x, int y, int w, int h, int r, uint8_t c)
	Fills a rounded rectangle (corners as gfx_roundRect()).
void	gfx_ellipse (int cx, int cy, int rx, int ry, uint8_t c)
	Draws an axis-aligned ellipse's 1-pixel outline, 2*rx+1 by 2*ry+1 pixels, centred on (cx, cy).
void	gfx_fillEllipse (int cx, int cy, int rx, int ry, uint8_t c)
	Draws a filled axis-aligned ellipse, 2*rx+1 by 2*ry+1 pixels, centred on (cx, cy).
void	gfx_dither (int x, int y, int w, int h, uint8_t c, uint8_t phase)
	Paints a 50% checkerboard of one colour over a rectangle, leaving the pixels in between alone.
void	gfx_remapRect (int x, int y, int w, int h, const uint8_t *remap)
	Recolours a rectangle in place through a 16-entry table: pixel = remap[pixel].

Detailed Description

Rounded rectangles, ellipses, dithered fills and in-place recolouring.

Clipped like everything in Drawing. Nothing here costs a sketch that does not call it: the linker drops what is unused.

Function Documentation

gfx_roundRect()

void gfx_roundRect	(	int	x,
		int	y,
		int	w,
		int	h,
		int	r,
		uint8_t	c
	)

Draws a rounded rectangle's 1-pixel outline.

Corners are pixel-art arcs, not chamfers; r is clamped to half the shorter side, and r = 0 is a plain rectangle.

Parameters

x	Left edge.
y	Top edge.
w	Width; 0 or less draws nothing.
h	Height; 0 or less draws nothing.
r	Corner radius in pixels.
c	Palette index.

gfx_fillRoundRect()

void gfx_fillRoundRect	(	int	x,
		int	y,
		int	w,
		int	h,
		int	r,
		uint8_t	c
	)

Fills a rounded rectangle (corners as gfx_roundRect()).

Parameters

x	Left edge.
y	Top edge.
w	Width; 0 or less draws nothing.
h	Height; 0 or less draws nothing.
r	Corner radius in pixels.
c	Palette index.

gfx_ellipse()

void gfx_ellipse	(	int	cx,
		int	cy,
		int	rx,
		int	ry,
		uint8_t	c
	)

Draws an axis-aligned ellipse's 1-pixel outline, 2*rx+1 by 2*ry+1 pixels, centred on (cx, cy).

Integer only, no square roots.

Parameters

cx	Centre column.
cy	Centre row.
rx	Horizontal radius in pixels.
ry	Vertical radius in pixels.
c	Palette index.

gfx_fillEllipse()

void gfx_fillEllipse	(	int	cx,
		int	cy,
		int	rx,
		int	ry,
		uint8_t	c
	)

Draws a filled axis-aligned ellipse, 2*rx+1 by 2*ry+1 pixels, centred on (cx, cy).

Parameters

cx	Centre column.
cy	Centre row.
rx	Horizontal radius in pixels.
ry	Vertical radius in pixels.
c	Palette index.

gfx_dither()

void gfx_dither	(	int	x,
		int	y,
		int	w,
		int	h,
		uint8_t	c,
		uint8_t	phase
	)

Paints a 50% checkerboard of one colour over a rectangle, leaving the pixels in between alone.

Darkened backdrops behind menus, felt, shadows.

Parameters

x	Left edge.
y	Top edge.
w	Width.
h	Height.
c	Palette index.
phase	0 paints pixels where x + y is even, 1 where it is odd.

gfx_remapRect()

void gfx_remapRect	(	int	x,
		int	y,
		int	w,
		int	h,
		const uint8_t *	remap
	)

Recolours a rectangle in place through a 16-entry table: pixel = remap[pixel].

Dimming, tinting, a hit flash on what is already drawn. A rectangle of 512 pixels or more builds a 256-entry table first and then costs one lookup per two pixels.

Parameters

x	Left edge.
y	Top edge.
w	Width.
h	Height.
remap	16 palette indices: the new colour for each old one.