cleaned up collision in shader, abstracted out raycast, and added gpu timing

This commit is contained in:
2024-10-03 15:04:14 -04:00
parent 4ddf2ddc87
commit 0dc5a9c2ba
21 changed files with 575 additions and 1187 deletions

View File

@@ -1,9 +1,9 @@
@group(0) @binding(0)
var<uniform> view: View;
@group(0) @binding(1)
var<storage, read> voxels: array<u32>;
var<storage, read> chunks: array<Chunk>;
@group(0) @binding(2)
var<storage, read> voxel_groups: array<VoxelGroup>;
var<storage, read> voxel_data: array<u32>;
@group(0) @binding(3)
var<storage, read> global_lights: array<GlobalLight>;
@group(0) @binding(4)
@@ -16,12 +16,11 @@ struct GlobalLight {
struct View {
transform: mat4x4<f32>,
zoom: f32,
chunk_scale: u32,
chunk_dist: u32,
};
struct VoxelGroup {
transform: mat4x4<f32>,
transform_inv: mat4x4<f32>,
scale: u32,
struct Chunk {
offset: u32,
};
@@ -38,7 +37,8 @@ fn main(@builtin(global_invocation_id) cell: vec3<u32>) {
let pixel_pos = vec2<f32>(
(vec2<f32>(cell.xy) / view_dim_f - vec2<f32>(0.5)) * vec2<f32>(2.0, -2.0 * aspect)
);
let pos = view.transform * vec4<f32>(pixel_pos, 1.0, 1.0);
let offset = vec3<f32>(f32(1u << (view.chunk_scale - 1)));
let pos = view.transform * vec4<f32>(pixel_pos, 1.0, 1.0) + vec4<f32>(offset, 0.0);
let dir = view.transform * vec4<f32>(normalize(vec3<f32>(pixel_pos, view.zoom)), 0.0);
var color = trace_full(pos, dir);
@@ -53,6 +53,7 @@ fn main(@builtin(global_invocation_id) cell: vec3<u32>) {
const LEAF_BIT = 1u << 31u;
const LEAF_MASK = ~LEAF_BIT;
const MAX_HITS = 10;
const ZERO3F = vec3<f32>(0.0);
const ZERO2F = vec2<f32>(0.0);
@@ -62,126 +63,122 @@ const MAX_ITERS = 10000;
// NOTE: CANNOT GO HIGHER THAN 23 due to how floating point
// numbers are stored and the bit manipulation used
const MAX_SCALE: u32 = 13;
const AMBIENT: f32 = 0.2;
const SPECULAR: f32 = 0.5;
fn trace_full(pos_view: vec4<f32>, dir_view: vec4<f32>) -> vec4<f32> {
let gi = 0;
let group = voxel_groups[gi];
if group.scale == 0 {
if arrayLength(&voxel_data) == 1 {
return vec4<f32>(0.0);
}
let dimensions = vec3<u32>(1u << group.scale);
let gi = 0;
let chunk = chunks[gi];
let side_len = 1u << view.chunk_scale;
let dimensions = vec3<u32>(side_len);
let dim_f = vec3<f32>(dimensions);
let dim_i = vec3<i32>(dimensions);
// transform so that group is at 0,0
let pos_start = (group.transform_inv * pos_view).xyz;
var dir = (group.transform_inv * dir_view).xyz;
if dir.x == 0 {dir.x = EPSILON;}
if dir.y == 0 {dir.y = EPSILON;}
if dir.z == 0 {dir.z = EPSILON;}
let pos_start = pos_view.xyz;
var dir = dir_view.xyz;
if dir.x == 0 { dir.x = EPSILON; }
if dir.y == 0 { dir.y = EPSILON; }
if dir.z == 0 { dir.z = EPSILON; }
let dir_if = sign(dir);
let dir_uf = max(dir_if, vec3<f32>(0.0));
// find where ray intersects with group
// closest (min) and furthest (max) corners of cube relative to direction
let pos_min = (vec3<f32>(1.0) - dir_uf) * dim_f;
let pos_max = dir_uf * dim_f;
// time of intersection; x = td + p, solve for t
let t_min = (pos_min - pos_start) / dir;
let t_max = (pos_max - pos_start) / dir;
// time of entrance and exit of the cube
let t_start = max(max(t_min.x, t_min.y), t_min.z);
let t_end = min(min(t_max.x, t_max.y), t_max.z);
if t_end < t_start { return vec4<f32>(0.0); }
// axis of intersection
let axis = select(select(2u, 1u, t_start == t_min.y), 0u, t_start == t_min.x);
// time to move entire side length in each direction
let inc_t = abs(1.0 / dir) * f32(side_len);
let t = max(0.0, t_start);
let inv_dir_bits = 7 - vec_to_dir(vec3<u32>(dir_uf));
let corner_adj = t_min - inc_t;
// calculate normals
var normals = mat3x3<f32>(
(group.transform * vec4<f32>(dir_if.x, 0.0, 0.0, 0.0)).xyz,
(group.transform * vec4<f32>(0.0, dir_if.y, 0.0, 0.0)).xyz,
(group.transform * vec4<f32>(0.0, 0.0, dir_if.z, 0.0)).xyz,
vec3<f32>(dir_if.x, 0.0, 0.0),
vec3<f32>(0.0, dir_if.y, 0.0),
vec3<f32>(0.0, 0.0, dir_if.z),
);
var axis = 0u;
// find where ray intersects with group
let pos_min = (vec3<f32>(1.0) - dir_uf) * dim_f;
// time of intersection; x = td + p, solve for t
var t_min = (pos_min - pos_start) / dir;
if outside3f(pos_start, ZERO3F, dim_f) {
// points of intersection
let px = pos_start + t_min.x * dir;
let py = pos_start + t_min.y * dir;
let pz = pos_start + t_min.z * dir;
let result = cast_ray(chunk.offset, t, axis, inv_dir_bits, inc_t, corner_adj);
return shade_ray(result, pos_start, dir_view.xyz, t_end, normals);
}
// check if point is in bounds
let hit = vec3<bool>(
inside2f(px.yz, ZERO2F, dim_f.yz),
inside2f(py.xz, ZERO2F, dim_f.xz),
inside2f(pz.xy, ZERO2F, dim_f.xy),
) && (t_min > ZERO3F);
if !any(hit) {
return vec4<f32>(0.0);
}
axis = select(select(2u, 1u, hit.y), 0u, hit.x);
}
let t_mult = f32(1u << (MAX_SCALE - group.scale));
t_min *= t_mult;
// time to move 1 unit in each direction
let full = f32(1u << MAX_SCALE);
let inc_t = abs(1.0 / dir) * full;
let t_offset = max(max(t_min.x, t_min.y), t_min.z);
var t = max(0.0, t_offset);
fn shade_ray(result: RayResult, pos_start: vec3<f32>, dir: vec3<f32>, t_end: f32, normals: mat3x3<f32>) -> vec4<f32> {
var hits = result.hits;
let dir_i = vec3<i32>(dir_if);
let dir_u = vec3<u32>(dir_uf);
let dir_bits = vec_to_dir(dir_u);
let inv_dir_bits = 7 - dir_bits;
var node_start = 1u;
var scale = MAX_SCALE - 1;
var scale_exp2 = 0.5;
var color = vec4<f32>(0.0);
var parents = array<u32, MAX_SCALE>();
var prev = LEAF_BIT;
var old_t = t / t_mult;
for (var i = 0u; i < result.len; i += 1u) {
let hit = hits[i];
let id = hit.id;
let t = hit.t;
let axis = hit.axis;
var child = 0u;
let next_t = select(hits[i + 1].t, t_end, i == result.len - 1);
var pos = pos_start + dir * t;
pos[axis] = round(pos[axis]) - f32(dir[axis] < 0.0);
let normal = select(select(normals[0], normals[1], axis == 1), normals[2], axis == 2);
let vcolor = shade(id, pos, normal, dir, next_t - t);
color += vcolor * (1.0 - color.a);
if color.a > FULL_ALPHA { break; }
}
return color;
}
struct RayHit {
t: f32,
id: u32,
axis: u32,
}
struct RayResult {
hits: array<RayHit, MAX_HITS>,
len: u32,
}
fn cast_ray(
data_offset: u32, t_start: f32, axis_start: u32,
inv_dir_bits: u32, inc_t: vec3<f32>, corner_adj: vec3<f32>
) -> RayResult {
var hits = array<RayHit, MAX_HITS>();
var depth = 0u;
var min_alpha = 0.0;
var t = t_start;
var axis = axis_start;
var node_start = 0u;
var scale = MAX_SCALE;
var scale_exp2 = 1.0;
var parents = array<u32, MAX_SCALE>();
var child = inv_dir_bits;
var vox_pos = vec3<f32>(1.0);
let t_center = t_min + scale_exp2 * inc_t;
if t > t_center.x { vox_pos.x = 1.5; child |= 4u; }
if t > t_center.y { vox_pos.y = 1.5; child |= 2u; }
if t > t_center.z { vox_pos.z = 1.5; child |= 1u; }
let min_adj = t_min - inc_t;
var prev = 0u;
var iters = 0;
loop {
if iters == MAX_ITERS {
return vec4<f32>(1.0, 0.0, 1.0, 1.0);
}
if iters == MAX_ITERS { break; }
iters += 1;
let t_corner = vox_pos * inc_t + min_adj;
let node = voxels[group.offset + node_start + (child ^ inv_dir_bits)];
let t_corner = vox_pos * inc_t + corner_adj;
let node = voxel_data[data_offset + node_start + (child ^ inv_dir_bits)];
if node >= LEAF_BIT {
// ignore consecutive identical leaves
if node != prev {
if node != LEAF_BIT {
let real_t = t / t_mult;
let dist = real_t - old_t;
old_t = real_t;
let filt = min(dist / 64.0, 1.0);
if prev == LEAF_BIT + 3 {
color.a += filt * (1.0 - color.a);
if color.a > FULL_ALPHA { break; }
}
var pos = (pos_view + dir_view * real_t).xyz;
pos[axis] = round(pos[axis]) - (1.0 - dir_uf[axis]);
let vcolor = get_color(node & LEAF_MASK, pos);
var normal = normals[axis];
let light_color = vec3<f32>(1.0);
let light_dir = global_lights[0].dir;
let diffuse = max(dot(light_dir, normal), 0.0) * light_color;
let ambient = AMBIENT * light_color;
let spec_val = pow(max(dot(dir_view.xyz, reflect(-light_dir, normal)), 0.0), 32.0) * SPECULAR;
let specular = spec_val * light_color;
let new_color = (ambient + diffuse + specular) * vcolor.xyz;
let new_a = min(vcolor.a + spec_val, 1.0);
color += vec4<f32>(new_color.xyz * new_a, new_a) * (1.0 - color.a);
if color.a > FULL_ALPHA { break; }
}
let id = node & LEAF_MASK;
hits[depth] = RayHit(t, id, axis);
min_alpha += min_alpha(id) * (1.0 - min_alpha);
depth += 1u;
prev = node;
if depth == 10 || min_alpha >= FULL_ALPHA { break; }
}
// move to next time point and determine which axis to move along
@@ -226,10 +223,15 @@ fn trace_full(pos_view: vec4<f32>, dir_view: vec4<f32>) -> vec4<f32> {
node_start = node;
}
}
// let fog = min(t / t_mult / 1000.0, 1.0);
// return vec4<f32>(color.xyz * (1.0 - fog) + vec3<f32>(fog), color.a * (1.0 - fog) + fog);
// return vec4<f32>(f32(iters) / f32(MAX_ITERS), 0.0, 0.0, 1.0);
return color;
return RayResult(hits, depth);
}
fn trace_chunk(
offset: u32,
inv_dir_bits: u32,
t: f32, t_mult: f32, inc_t: vec3<f32>,
min_adj: vec3<f32>
) {
}
fn dir_to_vec(bits: u32) -> vec3<u32> {
@@ -240,29 +242,53 @@ fn vec_to_dir(vec: vec3<u32>) -> u32 {
return vec.x * 4 + vec.y * 2 + vec.z * 1;
}
fn get_color(id: u32, pos: vec3<f32>) -> vec4<f32> {
fn min_alpha(id: u32) -> f32 {
switch id {
case 0u: {return 0.0;}
case 3u: {return 0.5;}
default: {return 1.0;}
}
}
const AMBIENT: f32 = 0.2;
const SPECULAR: f32 = 0.5;
// returns premultiplied
fn shade(id: u32, pos: vec3<f32>, normal: vec3<f32>, dir_view: vec3<f32>, dist: f32) -> vec4<f32> {
var color = vec4<f32>(0.0);
if id == 0 {
return color;
}
let random = random(floor(pos));
let random2 = random(floor(pos) + vec3<f32>(0.0001));
switch id {
case 0u: {
return vec4<f32>(0.0);
color = vec4<f32>(0.0);
}
case 1u: {
let color = vec3<f32>(0.5, 0.5, 0.5 + random * 0.2) * (random2 * 0.4 + 0.8);
return vec4<f32>(color, 1.0);
color = vec4<f32>(vec3<f32>(0.5, 0.5, 0.5 + random * 0.2) * (random2 * 0.4 + 0.8), 1.0);
}
case 2u: {
let color = vec3<f32>(0.4 + random * 0.2, 0.9, 0.4 + random * 0.2) * (random2 * 0.2 + 0.9);
return vec4<f32>(color, 1.0);
color = vec4<f32>(vec3<f32>(0.4 + random * 0.2, 0.9, 0.4 + random * 0.2) * (random2 * 0.2 + 0.9), 1.0);
}
case 3u: {
let color = vec3<f32>(0.5, 0.5, 1.0) * (random2 * 0.2 + 0.8);
return vec4<f32>(color, 0.5);
}
default: {
return vec4<f32>(1.0, 0.0, 0.0, 1.0);
let fog = min(dist / 64.0, 1.0);
let a = 0.5;
let rgb = vec3<f32>(0.5, 0.5, 1.0) * (random2 * 0.2 + 0.8);
color = vec4<f32>(rgb * (1.0 - fog * a), a + fog * (1.0 - a));
}
default: {}
}
let light_color = vec3<f32>(1.0);
let light_dir = global_lights[0].dir;
let diffuse = max(dot(light_dir, normal), 0.0) * light_color;
let ambient = AMBIENT * light_color;
let spec_val = pow(max(dot(dir_view.xyz, reflect(-light_dir, normal)), 0.0), 32.0) * SPECULAR;
let specular = spec_val * light_color;
let new_color = (ambient + diffuse + specular) * color.xyz;
let new_a = min(color.a + spec_val, 1.0);
return vec4<f32>(new_color * new_a, new_a);
}
fn random(pos: vec3<f32>) -> f32 {