1#import bevy_solari::world_cache::{
2    WORLD_CACHE_EMPTY_CELL,
3    world_cache_life,
4    world_cache_checksums,
5    world_cache_radiance,
6    world_cache_luminance_deltas,
7    world_cache_a,
8    world_cache_b,
9    world_cache_active_cell_indices,
10    world_cache_active_cells_count,
11}
12
13@group(2) @binding(0) var<storage, read_write> world_cache_active_cells_dispatch: vec3<u32>;
14
15var<workgroup> w1: array<u32, 1024u>;
16var<workgroup> w2: array<u32, 1024u>;
17
18@compute @workgroup_size(1024, 1, 1)
19fn decay_world_cache(@builtin(global_invocation_id) global_id: vec3<u32>) {
20    var life = world_cache_life[global_id.x];
21    if life > 0u {
22        life -= 1u;
23        world_cache_life[global_id.x] = life;
24
25        if life == 0u {
26            world_cache_checksums[global_id.x] = WORLD_CACHE_EMPTY_CELL;
27            world_cache_radiance[global_id.x] = vec4(0.0);
28            world_cache_luminance_deltas[global_id.x] = 0.0;
29        }
30    }
31}
32
33@compute @workgroup_size(1024, 1, 1)
34fn compact_world_cache_single_block(
35    @builtin(global_invocation_id) cell_id: vec3<u32>,
36    @builtin(local_invocation_index) t: u32,
37) {
38    if t == 0u { w1[0u] = 0u; } else { w1[t] = u32(world_cache_life[cell_id.x - 1u] != 0u); }; workgroupBarrier();
39    if t < 1u { w2[t] = w1[t]; } else { w2[t] = w1[t] + w1[t - 1u]; } workgroupBarrier();
40    if t < 2u { w1[t] = w2[t]; } else { w1[t] = w2[t] + w2[t - 2u]; } workgroupBarrier();
41    if t < 4u { w2[t] = w1[t]; } else { w2[t] = w1[t] + w1[t - 4u]; } workgroupBarrier();
42    if t < 8u { w1[t] = w2[t]; } else { w1[t] = w2[t] + w2[t - 8u]; } workgroupBarrier();
43    if t < 16u { w2[t] = w1[t]; } else { w2[t] = w1[t] + w1[t - 16u]; } workgroupBarrier();
44    if t < 32u { w1[t] = w2[t]; } else { w1[t] = w2[t] + w2[t - 32u]; } workgroupBarrier();
45    if t < 64u { w2[t] = w1[t]; } else { w2[t] = w1[t] + w1[t - 64u]; } workgroupBarrier();
46    if t < 128u { w1[t] = w2[t]; } else { w1[t] = w2[t] + w2[t - 128u]; } workgroupBarrier();
47    if t < 256u { w2[t] = w1[t]; } else { w2[t] = w1[t] + w1[t - 256u]; } workgroupBarrier();
48    if t < 512u { world_cache_a[cell_id.x] = w2[t]; } else { world_cache_a[cell_id.x] = w2[t] + w2[t - 512u]; }
49}
50
51@compute @workgroup_size(1024, 1, 1)
52fn compact_world_cache_blocks(@builtin(local_invocation_index) t: u32) {
53    if t == 0u { w1[0u] = 0u; } else { w1[t] = world_cache_a[t * 1024u - 1u]; }; workgroupBarrier();
54    if t < 1u { w2[t] = w1[t]; } else { w2[t] = w1[t] + w1[t - 1u]; } workgroupBarrier();
55    if t < 2u { w1[t] = w2[t]; } else { w1[t] = w2[t] + w2[t - 2u]; } workgroupBarrier();
56    if t < 4u { w2[t] = w1[t]; } else { w2[t] = w1[t] + w1[t - 4u]; } workgroupBarrier();
57    if t < 8u { w1[t] = w2[t]; } else { w1[t] = w2[t] + w2[t - 8u]; } workgroupBarrier();
58    if t < 16u { w2[t] = w1[t]; } else { w2[t] = w1[t] + w1[t - 16u]; } workgroupBarrier();
59    if t < 32u { w1[t] = w2[t]; } else { w1[t] = w2[t] + w2[t - 32u]; } workgroupBarrier();
60    if t < 64u { w2[t] = w1[t]; } else { w2[t] = w1[t] + w1[t - 64u]; } workgroupBarrier();
61    if t < 128u { w1[t] = w2[t]; } else { w1[t] = w2[t] + w2[t - 128u]; } workgroupBarrier();
62    if t < 256u { w2[t] = w1[t]; } else { w2[t] = w1[t] + w1[t - 256u]; } workgroupBarrier();
63    if t < 512u { world_cache_b[t] = w2[t]; } else { world_cache_b[t] = w2[t] + w2[t - 512u]; }
64}
65
66@compute @workgroup_size(1024, 1, 1)
67fn compact_world_cache_write_active_cells(
68    @builtin(global_invocation_id) cell_id: vec3<u32>,
69    @builtin(workgroup_id) workgroup_id: vec3<u32>,
70    @builtin(local_invocation_index) thread_index: u32,
71) {
72    let compacted_index = world_cache_a[cell_id.x] + world_cache_b[workgroup_id.x];
73    let cell_active = world_cache_life[cell_id.x] != 0u;
74
75    if cell_active {
76        world_cache_active_cell_indices[compacted_index] = cell_id.x;
77    }
78
79    if thread_index == 1023u && workgroup_id.x == 1023u {
80        world_cache_active_cells_count = compacted_index + u32(cell_active);
81        world_cache_active_cells_dispatch = vec3((world_cache_active_cells_count + 63u) / 64u, 1u, 1u);
82    }
83}