cdc::ui::qr Namespace Reference

Functions
void	packModule (uint8_t *out, uint16_t stride, uint8_t scale, uint8_t quiet, int mx, int my)
	Sets the packed pixels of one black QR module.
int	measure (const char *data, uint8_t max_version, uint8_t ecc, uint16_t *out_modules)
	Measures the module count for data without rendering.
int	render (const char *data, uint8_t max_version, uint8_t ecc, uint8_t scale, uint8_t quiet_modules, uint8_t *out, size_t out_size, uint16_t *out_stride_bytes, uint16_t *out_height_px)
	Encodes data and packs it into a 1-bpp raster.

Variables
constexpr uint16_t	QR_MAX_SIDE_PX = 1024
	Hard cap on the rendered side length in pixels (incl. quiet zone, scaled).

Function Documentation

measure()

int cdc::ui::qr::measure	(	const char *	data,
		uint8_t	max_version,
		uint8_t	ecc,
		uint16_t *	out_modules )

Measures the module count for data without rendering.

Parameters

data	NUL-terminated payload text.
max_version	Maximum QR version 1..20 (0 defaults to 20).
ecc	ECC level 0..3 (LOW..HIGH).
out_modules	Receives the side length in modules.

Returns

0 on success, negative on failure (bad args or data too long).

Definition at line 73 of file QrRaster.cpp.

Referenced by host_qr_measure(), and render().

packModule()

void cdc::ui::qr::packModule ( uint8_t * out, uint16_t stride, uint8_t scale, uint8_t quiet, int mx, int my )

inline

Sets the packed pixels of one black QR module.

Pure bit-packing shared by the firmware renderer and the host unit tests: module (mx, my) inks a scale x scale pixel block offset by the quiet zone. Rows are MSB-first, a set bit is black.

Parameters

out	Packed raster, stride bytes per row, pre-cleared to white.
stride	Bytes per row.
scale	Pixels per module, >= 1.
quiet	Quiet-zone width in modules per edge.
mx	Module column.
my	Module row.

Definition at line 33 of file QrRaster.h.

References cdc::ui::scale.

render()

int cdc::ui::qr::render	(	const char *	data,
		uint8_t	max_version,
		uint8_t	ecc,
		uint8_t	scale,
		uint8_t	quiet_modules,
		uint8_t *	out,
		size_t	out_size,
		uint16_t *	out_stride_bytes,
		uint16_t *	out_height_px )

Encodes data and packs it into a 1-bpp raster.

The rendered side is (modules + 2 * quiet_modules) * scale pixels; the quiet zone is white. Rows are packed MSB-first with a set bit meaning black.

Parameters

data	NUL-terminated payload text.
max_version	Maximum QR version 1..20 (0 defaults to 20).
ecc	ECC level 0..3 (LOW..HIGH).
scale	Pixels per module, >= 1.
quiet_modules	Quiet-zone width in modules per edge.
out	Caller buffer for the packed rows.
out_size	Capacity of out in bytes.
out_stride_bytes	Receives the row stride (side_px + 7) / 8.
out_height_px	Receives the side length in pixels.

Returns

0 on success, -1 on encode failure, -2 on bad args / side too large, -3 when out is too small.

Definition at line 84 of file QrRaster.cpp.

References measure(), QR_MAX_SIDE_PX, and cdc::ui::scale.

Referenced by host_qr_render_bitmap().

Variable Documentation

QR_MAX_SIDE_PX

uint16_t cdc::ui::qr::QR_MAX_SIDE_PX = 1024

inlineconstexpr

Hard cap on the rendered side length in pixels (incl. quiet zone, scaled).

Definition at line 18 of file QrRaster.h.

Referenced by render().