1#import bevy_render::view::View
2#import bevy_render::maths
3#import bevy_pbr::mesh_types::SkinnedMesh
4#import bevy_mod_outline::common::VertexOutput
5
6struct Instance {
7    world_from_local: mat3x4<f32>,
8    world_plane_origin: vec3<f32>,
9    world_plane_offset: vec3<f32>,
10    volume_offset: f32,
11    volume_colour: vec4<f32>,
12    stencil_offset: f32,
13    alpha_mask_threshold: f32,
14    first_vertex_index: u32,
15};
16
17struct Vertex {
18    @location(0) position: vec3<f32>,
19    @builtin(instance_index) instance_index: u32,
20#ifndef VERTEX_OFFSET_ZERO
21    @location(1) outline_normal: vec3<f32>,
22#endif
23#ifdef ALPHA_MASK_TEXTURE
24    @location(2) uv: vec2<f32>,
25#endif
26#ifdef SKINNED
27    @location(5) joint_indices: vec4<u32>,
28    @location(6) joint_weights: vec4<f32>,
29#endif
30#ifdef MORPH_TARGETS
31    @builtin(vertex_index) index: u32,
32#endif
33};
34
35struct OutlineViewUniform {
36    @align(16)
37    clip_from_world: mat4x4<f32>,
38    world_from_view_a: mat2x4<f32>,
39    world_from_view_b: f32,
40    aspect: f32,
41    scale: vec2<f32>,
42};
43
44@group(0) @binding(0)
45var<uniform> view_uniform: OutlineViewUniform;
46
47#import bevy_pbr::skinning
48#import bevy_pbr::morph
49
50#ifdef INSTANCE_BATCH_SIZE
51@group(2) @binding(0) var<uniform> mesh: array<Instance, #{INSTANCE_BATCH_SIZE}u>;
52#else
53@group(2) @binding(0) var<storage> mesh: array<Instance>;
54#endif
55
56#ifdef MORPH_TARGETS
57fn morph_vertex(vertex_in: Vertex) -> Vertex {
58    var vertex = vertex_in;
59    let first_vertex = mesh[vertex.instance_index].first_vertex_index;
60    let vertex_index = vertex.index - first_vertex;
61
62    let weight_count = bevy_pbr::morph::layer_count();
63    for (var i: u32 = 0u; i < weight_count; i ++) {
64        let weight = bevy_pbr::morph::weight_at(i);
65        if weight == 0.0 {
66            continue;
67        }
68        vertex.position += weight * bevy_pbr::morph::morph(vertex_index, bevy_pbr::morph::position_offset, i);
69    }
70    return vertex;
71}
72#endif
73
74fn mat4to3(m: mat4x4<f32>) -> mat3x3<f32> {
75    return mat3x3<f32>(
76        m[0].xyz, m[1].xyz, m[2].xyz
77    );
78}
79
80fn model_origin_z(plane: vec3<f32>, view_proj: mat4x4<f32>) -> f32 {
81    var proj_zw = mat4x2<f32>(
82        view_proj[0].zw, view_proj[1].zw,
83        view_proj[2].zw, view_proj[3].zw);
84    var zw = proj_zw * vec4<f32>(plane, 1.0);
85    return zw.x / zw.y;
86}
87
88@vertex
89fn vertex(vertex_no_morph: Vertex) -> VertexOutput {
90    let iid = vertex_no_morph.instance_index;
91#ifdef MORPH_TARGETS
92    var vertex = morph_vertex(vertex_no_morph);
93#else
94    var vertex = vertex_no_morph;
95#endif
96#ifdef SKINNED
97    let model = bevy_pbr::skinning::skin_model(vertex.joint_indices, vertex.joint_weights);
98#else
99    let model = bevy_render::maths::affine3_to_square(mesh[iid].world_from_local);
100#endif
101    let clip_pos = view_uniform.clip_from_world * (model * vec4<f32>(vertex.position, 1.0));
102#ifdef VOLUME
103    let offset = mesh[iid].volume_offset;
104#else
105    let offset = mesh[iid].stencil_offset;
106#endif
107#ifdef VERTEX_OFFSET_ZERO
108    let out_xy = clip_pos.xy;
109#else
110    let clip_norm = mat4to3(view_uniform.clip_from_world) * (mat4to3(model) * vertex.outline_normal);
111    let corrected_norm = normalize(clip_norm.xy * vec2<f32>(view_uniform.aspect, 1.0));
112    let ndc_delta = offset * corrected_norm * view_uniform.scale * clip_pos.w;
113    let out_xy = clip_pos.xy + ndc_delta;
114#endif
115    var out: VertexOutput;
116    out.position = vec4<f32>(out_xy, clip_pos.zw);
117#ifdef FLAT_DEPTH
118#ifdef PLANE_OFFSET_ZERO
119    let world_plane = mesh[iid].world_plane_origin;
120#else
121    let world_from_view = bevy_render::maths::mat2x4_f32_to_mat3x3_unpack(view_uniform.world_from_view_a, view_uniform.world_from_view_b);
122    let model_eye = normalize(world_from_view * vec3<f32>(0.0, 0.0, -1.0));
123    let world_plane = mesh[iid].world_plane_origin + model_eye * mesh[iid].world_plane_offset;
124#endif
125    out.flat_depth = model_origin_z(world_plane, view_uniform.clip_from_world);
126#endif
127#ifdef VOLUME
128    out.volume_colour = mesh[iid].volume_colour;
129#endif
130#ifdef ALPHA_MASK_TEXTURE
131    out.alpha_mask_threshold = mesh[iid].alpha_mask_threshold;
132    out.uv = vertex.uv;
133#endif
134    return out;
135}