Struct GpuStrip 

#[repr(C)]
pub struct GpuStrip {
    pub x: u16,
    pub y: u16,
    pub width: u16,
    pub dense_width_or_rect_height: u16,
    pub col_idx_or_rect_frac: u32,
    pub payload: u32,
    pub paint_and_rect_flag: u32,
    pub depth_index: u32,
}

One strip instance, matching the shaders’ StripInstance byte for byte.

Three of the fields are overloaded by RECT_STRIP_FLAG, which is why they are named for both readings.

Fields

x: u16

Left edge in pixels.

y: u16

Top edge in pixels (a multiple of Tile::HEIGHT).

width: u16

Width in pixels.

dense_width_or_rect_height: u16

Width of the alpha-sampled (dense) part in pixels, or, for a rect instance, the rect’s height in pixels.

col_idx_or_rect_frac: u32

Index of the instance’s first alpha column in the alpha texture, or, for a rect instance, its packed coverage fraction.

payload: u32

Paint-dependent payload — a packed color, or the coordinates the paint is sampled at.

paint_and_rect_flag: u32

Packed paint descriptor, with RECT_STRIP_FLAG in bit 31.

depth_index: u32

Painter’s-order index driving early-z rejection: the backmost draw is 0 and each draw in front of it increments.

Implementations

impl GpuStrip

pub const QUAD_VERTICES: u32 = 4

Vertices in the quad each instance expands to.

pub fn vertex_attributes() -> [VertexAttribute; 6]

The six Uint32 vertex attributes the 24-byte instance is read through, at shader locations 0-5.

The u16 pairs are read as packed u32s and unpacked in the shader, so the attribute list stays uniform.

pub fn vertex_layout() -> VertexLayout

The instance-stepped vertex buffer layout over GpuStrip.

pub fn vertex_range() -> Range<u32>

The vertex range of a strip draw: one quad, built in the shader from the vertex index, with no vertex buffer behind it.

pub fn instance_range(first_instance: u32, count: u32) -> Range<u32>

The instance range of a strip draw covering count instances from first_instance — paired with Self::vertex_range for one draw call.

pub fn from_strip(strip: &Strip, width: u16, draw: StripDraw) -> Self

The alpha-sampled instance for strip, width pixels wide.

The strip’s alpha index becomes the instance’s first alpha column, and the instance is dense across its whole width: every column samples coverage.

pub fn from_strip_pair(strip: &Strip, next: &Strip, draw: StripDraw) -> Self

The alpha-sampled instance for strip, taking its width from next — the strip immediately after it in the same run, which is where a strip’s extent is recorded.

pub fn gap_fill(strip: &Strip, next: &Strip, draw: StripDraw) -> Option<Self>

The solid instance filling the gap between strip and next, or None when there is no gap to fill.

A gap is filled only when next carries the fill-gap flag and sits on the same strip row: the flag means “the winding between me and the previous strip is non-zero”, which says nothing about a strip on another row. The instance samples no coverage, so its dense width and column index are both zero.

pub fn solid_fill(x: u16, y: u16, width: u16, draw: StripDraw) -> Self

A solid instance covering one strip row, sampling no coverage.

pub fn from_rect( x: u16, y: u16, width: u16, height: u16, frac: u32, draw: StripDraw, ) -> Self

A rectangle instance of width x height pixels with packed coverage fraction frac, flagged with RECT_STRIP_FLAG.

Unlike a strip, a rect instance is not bound to one strip row: its height is carried in the instance itself.

pub const fn is_rect(&self) -> bool

Whether this instance is a rectangle rather than a strip.

pub const fn paint(&self) -> u32

The packed paint descriptor with RECT_STRIP_FLAG masked off.

Trait Implementations

impl Clone for GpuStrip

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for GpuStrip

impl Debug for GpuStrip

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

Formats the value using the given formatter.

impl Eq for GpuStrip

impl PartialEq for GpuStrip

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Pod for GpuStrip

impl StructuralPartialEq for GpuStrip

impl Zeroable for GpuStrip

fn zeroed() -> Self

Calls zeroed.