Struct QuarterScan 

pub struct QuarterScan<const PANEL_ROWS: usize, const PANEL_COLS: usize, V: Variant = SectionsSwapped> { /* private fields */ }

Pixel remapper for “quarter-scan” panels (1/16-scan on 64×64 panels)

Some LED panels — particularly 64×64 modules — use fewer row-address steps than the row count would suggest. A 1/16-scan 64×64 panel has only 16 row addresses (A–D) instead of the 32 a 1/32-scan panel would use, and lights four rows at a time: rows n, n+16, n+32 and n+48 for address n. To make this work with the two HUB75 data channels, the panel internally wires each channel’s shift register as two side-by-side 64-column sections, so the physical framebuffer is 2× wider and 2× shorter than the logical display (32×128 for a 64×64 panel).

The mapping splits the panel into four groups of PANEL_ROWS / 4 consecutive rows and places them side by side. How the four groups are wired to the four (channel, section) slots varies by driver chip and manufacturer (FM6126, ICN2037, MBI5153, etc.); the V type parameter selects the wiring — see the quarter_scan module for the built-in variants. The default quarter_scan::SectionsSwapped (verified on hardware) maps:

virtual rows	channel	section (framebuffer columns)
0..16	1 (top)	1 (64..128)
16..32	1 (top)	0 (0..64)
32..48	2 (bottom)	1 (64..128)
48..64	2 (bottom)	0 (0..64)

Type Parameters

• PANEL_ROWS — Logical row count of the panel (e.g. 64)
• PANEL_COLS — Logical column count of the panel (e.g. 64)
• V — Group → slot wiring variant (see quarter_scan); defaults to quarter_scan::SectionsSwapped

Framebuffer geometry

The underlying framebuffer must be allocated with:

• rows = PANEL_ROWS / 2 (e.g. 32 for a 64-row panel — 16 addresses × 2 channels)
• cols = PANEL_COLS * 2 (e.g. 128 for a 64-column panel — 2 sections per channel)

For the bitplane framebuffers this means DmaFrameBuffer<{ PANEL_ROWS / 4 }, { PANEL_COLS * 2 }, PLANES> because their NROWS parameter counts row-address steps (row pairs).

Trait Implementations

impl<const PANEL_ROWS: usize, const PANEL_COLS: usize, V: Debug + Variant> Debug for QuarterScan<PANEL_ROWS, PANEL_COLS, V>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<const PANEL_ROWS: usize, const PANEL_COLS: usize, V: Variant> PixelRemapper for QuarterScan<PANEL_ROWS, PANEL_COLS, V>

const VIRT_ROWS: usize = PANEL_ROWS

Number of rows in the virtual panel

const VIRT_COLS: usize = PANEL_COLS

Number of columns in the virtual panel

const FB_ROWS: usize

Number of rows in the actual framebuffer

const FB_COLS: usize

Number of columns in the actual framebuffer

fn remap_xy(x: usize, y: usize) -> (usize, usize)

Remap an x,y coordinate to a framebuffer pixel

fn remap<C: PixelColor>(pixel: Pixel<C>) -> Pixel<C>

Remap a virtual pixel to a framebuffer pixel

fn remap_point(point: Point) -> Point

Remap a virtual point to a framebuffer point

fn virtual_size() -> (usize, usize)

Size of the virtual panel

fn fb_size() -> (usize, usize)

Size of the framebuffer that this remaps to