Enum Topology 

pub enum Topology {
    PointList,
    LineList,
    LineStrip,
    TriangleList,
    TriangleStrip,
    LineListAdjacency,
    LineStripAdjacency,
    TriangleListAdjacency,
    TriangleStripAdjacency,
}

How a draw’s vertices make primitives (D3D’s primitive topologies a geometry shader can follow).

Variants

PointList

Each vertex is a point.

LineList

Every two vertices make a line.

LineStrip

Each vertex after the first makes a line with the one before it.

TriangleList

Every three vertices make a triangle.

TriangleStrip

Each vertex after the second makes a triangle with the two before it (odd triangles swap their last two vertices).

LineListAdjacency

Every four vertices make a line with its two neighbours.

LineStripAdjacency

A strip of lines with an adjacent vertex at each end.

TriangleListAdjacency

Every six vertices make a triangle with its three neighbours.

TriangleStripAdjacency

A strip of triangles with adjacency, numbered as D3D11 numbers them.

Implementations

impl Topology

pub fn input(self) -> GsInput

The primitive a geometry program reads to be drawn with this topology.

pub fn primitives(self, vertices: usize) -> Vec<Vec<usize>>

The primitives of a draw of vertices vertices, each as the indices of its vertices in the order the geometry program reads them (GsInput::vertices of them). Vertices that complete no primitive are ignored.

• A strip’s primitive i is [i, i + 1, ...], a triangle strip’s odd primitive [i, i + 2, i + 1] (its last two swapped).
• A line with adjacency is [before, start, end, after].
• A triangle with adjacency is [a, adjacent to a-b, b, adjacent to b-c, c, adjacent to c-a].
• A triangle strip with adjacency is the vertices 0, 2, 4, ... of a triangle strip, and between them the vertices that are adjacent to its edges (an odd vertex 2i + 1 the first’s 0-2 edge): for n = (vertices - 4) / 2 primitives, primitive i (even) is [2i, 2i - 2 (1 for i = 0), 2i + 2, 2i + 6, 2i + 4, 2i + 3] and primitive i (odd) [2i, 2i + 3, 2i + 4, 2i + 6, 2i + 2, 2i - 2], the vertex 2i + 6 that the last primitive does not have replaced by 2i + 5.

Trait Implementations

impl Clone for Topology

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 Topology

impl Debug for Topology

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

Formats the value using the given formatter.

impl Eq for Topology

impl From<GsOutput> for Topology

fn from(output: GsOutput) -> Self

The topology of the strips a program’s output makes.

impl PartialEq for Topology

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Topology