astrelis-geometry 0.2.4

Customizable 2D geometry rendering for Astrelis Game Engine
Documentation 
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// Fill shader for geometry rendering
// Renders filled triangles with instancing support

struct ProjectionUniform {
    matrix: mat4x4<f32>,
}

@group(0) @binding(0)
var<uniform> projection: ProjectionUniform;

struct VertexInput {
    @location(0) position: vec2<f32>,
}

struct InstanceInput {
    @location(2) transform_row0: vec4<f32>,
    @location(3) transform_row1: vec4<f32>,
    @location(4) color: vec4<f32>,
}

struct VertexOutput {
    @builtin(position) position: vec4<f32>,
    @location(0) color: vec4<f32>,
}

@vertex
fn vs_main(vertex: VertexInput, instance: InstanceInput) -> VertexOutput {
    var out: VertexOutput;

    // Apply 2D transform
    // transform_row0 = [a, b, 0, 0]
    // transform_row1 = [c, d, tx, ty]
    let a = instance.transform_row0.x;
    let b = instance.transform_row0.y;
    let c = instance.transform_row1.x;
    let d = instance.transform_row1.y;
    let tx = instance.transform_row1.z;
    let ty = instance.transform_row1.w;

    let transformed = vec2<f32>(
        a * vertex.position.x + c * vertex.position.y + tx,
        b * vertex.position.x + d * vertex.position.y + ty
    );

    out.position = projection.matrix * vec4<f32>(transformed, 0.0, 1.0);
    out.color = instance.color;

    return out;
}

@fragment
fn fs_main(in: VertexOutput) -> @location(0) vec4<f32> {
    return in.color;
}