mirror of
https://github.com/godotengine/godot.git
synced 2024-12-27 11:24:59 +08:00
473 lines
13 KiB
GLSL
473 lines
13 KiB
GLSL
#[compute]
|
|
|
|
#version 450
|
|
|
|
VERSION_DEFINES
|
|
|
|
layout(local_size_x = 64, local_size_y = 1, local_size_z = 1) in;
|
|
|
|
#define MAX_CASCADES 8
|
|
|
|
layout(set = 0, binding = 1) uniform texture3D sdf_cascades[MAX_CASCADES];
|
|
layout(set = 0, binding = 2) uniform sampler linear_sampler;
|
|
|
|
layout(set = 0, binding = 3, std430) restrict readonly buffer DispatchData {
|
|
uint x;
|
|
uint y;
|
|
uint z;
|
|
uint total_count;
|
|
}
|
|
dispatch_data;
|
|
|
|
struct ProcessVoxel {
|
|
uint position; //xyz 7 bit packed, extra 11 bits for neigbours
|
|
uint albedo; //rgb bits 0-15 albedo, bits 16-21 are normal bits (set if geometry exists toward that side), extra 11 bits for neibhbours
|
|
uint light; //rgbe8985 encoded total saved light, extra 2 bits for neighbours
|
|
uint light_aniso; //55555 light anisotropy, extra 2 bits for neighbours
|
|
//total neighbours: 26
|
|
};
|
|
|
|
#ifdef MODE_PROCESS_STATIC
|
|
layout(set = 0, binding = 4, std430) restrict buffer ProcessVoxels {
|
|
#else
|
|
layout(set = 0, binding = 4, std430) restrict buffer readonly ProcessVoxels {
|
|
#endif
|
|
ProcessVoxel data[];
|
|
}
|
|
process_voxels;
|
|
|
|
layout(r32ui, set = 0, binding = 5) uniform restrict uimage3D dst_light;
|
|
layout(rgba8, set = 0, binding = 6) uniform restrict image3D dst_aniso0;
|
|
layout(rg8, set = 0, binding = 7) uniform restrict image3D dst_aniso1;
|
|
|
|
struct CascadeData {
|
|
vec3 offset; //offset of (0,0,0) in world coordinates
|
|
float to_cell; // 1/bounds * grid_size
|
|
ivec3 probe_world_offset;
|
|
uint pad;
|
|
};
|
|
|
|
layout(set = 0, binding = 8, std140) uniform Cascades {
|
|
CascadeData data[MAX_CASCADES];
|
|
}
|
|
cascades;
|
|
|
|
#define LIGHT_TYPE_DIRECTIONAL 0
|
|
#define LIGHT_TYPE_OMNI 1
|
|
#define LIGHT_TYPE_SPOT 2
|
|
|
|
struct Light {
|
|
vec3 color;
|
|
float energy;
|
|
|
|
vec3 direction;
|
|
bool has_shadow;
|
|
|
|
vec3 position;
|
|
float attenuation;
|
|
|
|
uint type;
|
|
float spot_angle;
|
|
float spot_attenuation;
|
|
float radius;
|
|
|
|
vec4 shadow_color;
|
|
};
|
|
|
|
layout(set = 0, binding = 9, std140) buffer restrict readonly Lights {
|
|
Light data[];
|
|
}
|
|
lights;
|
|
|
|
layout(set = 0, binding = 10) uniform texture2DArray lightprobe_texture;
|
|
|
|
layout(push_constant, binding = 0, std430) uniform Params {
|
|
vec3 grid_size;
|
|
uint max_cascades;
|
|
|
|
uint cascade;
|
|
uint light_count;
|
|
uint process_offset;
|
|
uint process_increment;
|
|
|
|
int probe_axis_size;
|
|
bool multibounce;
|
|
float y_mult;
|
|
uint pad;
|
|
}
|
|
params;
|
|
|
|
vec2 octahedron_wrap(vec2 v) {
|
|
vec2 signVal;
|
|
signVal.x = v.x >= 0.0 ? 1.0 : -1.0;
|
|
signVal.y = v.y >= 0.0 ? 1.0 : -1.0;
|
|
return (1.0 - abs(v.yx)) * signVal;
|
|
}
|
|
|
|
vec2 octahedron_encode(vec3 n) {
|
|
// https://twitter.com/Stubbesaurus/status/937994790553227264
|
|
n /= (abs(n.x) + abs(n.y) + abs(n.z));
|
|
n.xy = n.z >= 0.0 ? n.xy : octahedron_wrap(n.xy);
|
|
n.xy = n.xy * 0.5 + 0.5;
|
|
return n.xy;
|
|
}
|
|
|
|
void main() {
|
|
uint voxel_index = uint(gl_GlobalInvocationID.x);
|
|
|
|
//used for skipping voxels every N frames
|
|
voxel_index = params.process_offset + voxel_index * params.process_increment;
|
|
|
|
if (voxel_index >= dispatch_data.total_count) {
|
|
return;
|
|
}
|
|
|
|
uint voxel_position = process_voxels.data[voxel_index].position;
|
|
|
|
//keep for storing to texture
|
|
ivec3 positioni = ivec3((uvec3(voxel_position, voxel_position, voxel_position) >> uvec3(0, 7, 14)) & uvec3(0x7F));
|
|
|
|
vec3 position = vec3(positioni) + vec3(0.5);
|
|
position /= cascades.data[params.cascade].to_cell;
|
|
position += cascades.data[params.cascade].offset;
|
|
|
|
uint voxel_albedo = process_voxels.data[voxel_index].albedo;
|
|
|
|
vec3 albedo = vec3(uvec3(voxel_albedo >> 10, voxel_albedo >> 5, voxel_albedo) & uvec3(0x1F)) / float(0x1F);
|
|
vec3 light_accum[6];
|
|
|
|
uint valid_aniso = (voxel_albedo >> 15) & 0x3F;
|
|
|
|
{
|
|
uint rgbe = process_voxels.data[voxel_index].light;
|
|
|
|
//read rgbe8985
|
|
float r = float((rgbe & 0xff) << 1);
|
|
float g = float((rgbe >> 8) & 0x1ff);
|
|
float b = float(((rgbe >> 17) & 0xff) << 1);
|
|
float e = float((rgbe >> 25) & 0x1F);
|
|
float m = pow(2.0, e - 15.0 - 9.0);
|
|
|
|
vec3 l = vec3(r, g, b) * m;
|
|
|
|
uint aniso = process_voxels.data[voxel_index].light_aniso;
|
|
for (uint i = 0; i < 6; i++) {
|
|
float strength = ((aniso >> (i * 5)) & 0x1F) / float(0x1F);
|
|
light_accum[i] = l * strength;
|
|
}
|
|
}
|
|
|
|
const vec3 aniso_dir[6] = vec3[](
|
|
vec3(1, 0, 0),
|
|
vec3(0, 1, 0),
|
|
vec3(0, 0, 1),
|
|
vec3(-1, 0, 0),
|
|
vec3(0, -1, 0),
|
|
vec3(0, 0, -1));
|
|
|
|
// Raytrace light
|
|
|
|
vec3 pos_to_uvw = 1.0 / params.grid_size;
|
|
vec3 uvw_ofs = pos_to_uvw * 0.5;
|
|
|
|
for (uint i = 0; i < params.light_count; i++) {
|
|
float attenuation = 1.0;
|
|
vec3 direction;
|
|
float light_distance = 1e20;
|
|
|
|
switch (lights.data[i].type) {
|
|
case LIGHT_TYPE_DIRECTIONAL: {
|
|
direction = -lights.data[i].direction;
|
|
} break;
|
|
case LIGHT_TYPE_OMNI: {
|
|
vec3 rel_vec = lights.data[i].position - position;
|
|
direction = normalize(rel_vec);
|
|
light_distance = length(rel_vec);
|
|
rel_vec.y /= params.y_mult;
|
|
attenuation = pow(clamp(1.0 - length(rel_vec) / lights.data[i].radius, 0.0, 1.0), lights.data[i].attenuation);
|
|
} break;
|
|
case LIGHT_TYPE_SPOT: {
|
|
vec3 rel_vec = lights.data[i].position - position;
|
|
direction = normalize(rel_vec);
|
|
light_distance = length(rel_vec);
|
|
rel_vec.y /= params.y_mult;
|
|
attenuation = pow(clamp(1.0 - length(rel_vec) / lights.data[i].radius, 0.0, 1.0), lights.data[i].attenuation);
|
|
|
|
float angle = acos(dot(normalize(rel_vec), -lights.data[i].direction));
|
|
if (angle > lights.data[i].spot_angle) {
|
|
attenuation = 0.0;
|
|
} else {
|
|
float d = clamp(angle / lights.data[i].spot_angle, 0, 1);
|
|
attenuation *= pow(1.0 - d, lights.data[i].spot_attenuation);
|
|
}
|
|
} break;
|
|
}
|
|
|
|
if (attenuation < 0.001) {
|
|
continue;
|
|
}
|
|
|
|
bool hit = false;
|
|
|
|
vec3 ray_pos = position;
|
|
vec3 ray_dir = direction;
|
|
vec3 inv_dir = 1.0 / ray_dir;
|
|
|
|
//this is how to properly bias outgoing rays
|
|
float cell_size = 1.0 / cascades.data[params.cascade].to_cell;
|
|
ray_pos += sign(direction) * cell_size * 0.48; // go almost to the box edge but remain inside
|
|
ray_pos += ray_dir * 0.4 * cell_size; //apply a small bias from there
|
|
|
|
for (uint j = params.cascade; j < params.max_cascades; j++) {
|
|
//convert to local bounds
|
|
vec3 pos = ray_pos - cascades.data[j].offset;
|
|
pos *= cascades.data[j].to_cell;
|
|
float local_distance = light_distance * cascades.data[j].to_cell;
|
|
|
|
if (any(lessThan(pos, vec3(0.0))) || any(greaterThanEqual(pos, params.grid_size))) {
|
|
continue; //already past bounds for this cascade, goto next
|
|
}
|
|
|
|
//find maximum advance distance (until reaching bounds)
|
|
vec3 t0 = -pos * inv_dir;
|
|
vec3 t1 = (params.grid_size - pos) * inv_dir;
|
|
vec3 tmax = max(t0, t1);
|
|
float max_advance = min(tmax.x, min(tmax.y, tmax.z));
|
|
|
|
max_advance = min(local_distance, max_advance);
|
|
|
|
float advance = 0.0;
|
|
float occlusion = 1.0;
|
|
|
|
while (advance < max_advance) {
|
|
//read how much to advance from SDF
|
|
vec3 uvw = (pos + ray_dir * advance) * pos_to_uvw;
|
|
|
|
float distance = texture(sampler3D(sdf_cascades[j], linear_sampler), uvw).r * 255.0 - 1.0;
|
|
if (distance < 0.001) {
|
|
//consider hit
|
|
hit = true;
|
|
break;
|
|
}
|
|
|
|
occlusion = min(occlusion, distance);
|
|
|
|
advance += distance;
|
|
}
|
|
|
|
if (hit) {
|
|
attenuation *= occlusion;
|
|
break;
|
|
}
|
|
|
|
if (advance >= local_distance) {
|
|
break; //past light distance, abandon search
|
|
}
|
|
//change ray origin to collision with bounds
|
|
pos += ray_dir * max_advance;
|
|
pos /= cascades.data[j].to_cell;
|
|
pos += cascades.data[j].offset;
|
|
light_distance -= max_advance / cascades.data[j].to_cell;
|
|
ray_pos = pos;
|
|
}
|
|
|
|
if (!hit) {
|
|
vec3 light = albedo * lights.data[i].color.rgb * lights.data[i].energy * attenuation;
|
|
|
|
for (int j = 0; j < 6; j++) {
|
|
if (bool(valid_aniso & (1 << j))) {
|
|
light_accum[j] += max(0.0, dot(aniso_dir[j], direction)) * light;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Add indirect light
|
|
|
|
if (params.multibounce) {
|
|
vec3 pos = (vec3(positioni) + vec3(0.5)) * float(params.probe_axis_size - 1) / params.grid_size;
|
|
ivec3 probe_base_pos = ivec3(pos);
|
|
|
|
vec4 probe_accum[6] = vec4[](vec4(0.0), vec4(0.0), vec4(0.0), vec4(0.0), vec4(0.0), vec4(0.0));
|
|
float weight_accum[6] = float[](0, 0, 0, 0, 0, 0);
|
|
|
|
ivec3 tex_pos = ivec3(probe_base_pos.xy, int(params.cascade));
|
|
tex_pos.x += probe_base_pos.z * int(params.probe_axis_size);
|
|
|
|
tex_pos.xy = tex_pos.xy * (OCT_SIZE + 2) + ivec2(1);
|
|
|
|
vec3 base_tex_posf = vec3(tex_pos);
|
|
vec2 tex_pixel_size = 1.0 / vec2(ivec2((OCT_SIZE + 2) * params.probe_axis_size * params.probe_axis_size, (OCT_SIZE + 2) * params.probe_axis_size));
|
|
vec3 probe_uv_offset = (ivec3(OCT_SIZE + 2, OCT_SIZE + 2, (OCT_SIZE + 2) * params.probe_axis_size)) * tex_pixel_size.xyx;
|
|
|
|
for (uint j = 0; j < 8; j++) {
|
|
ivec3 offset = (ivec3(j) >> ivec3(0, 1, 2)) & ivec3(1, 1, 1);
|
|
ivec3 probe_posi = probe_base_pos;
|
|
probe_posi += offset;
|
|
|
|
// Compute weight
|
|
|
|
vec3 probe_pos = vec3(probe_posi);
|
|
vec3 probe_to_pos = pos - probe_pos;
|
|
vec3 probe_dir = normalize(-probe_to_pos);
|
|
|
|
// Compute lightprobe texture position
|
|
|
|
vec3 trilinear = vec3(1.0) - abs(probe_to_pos);
|
|
|
|
for (uint k = 0; k < 6; k++) {
|
|
if (bool(valid_aniso & (1 << k))) {
|
|
vec3 n = aniso_dir[k];
|
|
float weight = trilinear.x * trilinear.y * trilinear.z * max(0.005, dot(n, probe_dir));
|
|
|
|
vec3 tex_posf = base_tex_posf + vec3(octahedron_encode(n) * float(OCT_SIZE), 0.0);
|
|
tex_posf.xy *= tex_pixel_size;
|
|
|
|
vec3 pos_uvw = tex_posf;
|
|
pos_uvw.xy += vec2(offset.xy) * probe_uv_offset.xy;
|
|
pos_uvw.x += float(offset.z) * probe_uv_offset.z;
|
|
vec4 indirect_light = textureLod(sampler2DArray(lightprobe_texture, linear_sampler), pos_uvw, 0.0);
|
|
|
|
probe_accum[k] += indirect_light * weight;
|
|
weight_accum[k] += weight;
|
|
}
|
|
}
|
|
}
|
|
|
|
for (uint k = 0; k < 6; k++) {
|
|
if (weight_accum[k] > 0.0) {
|
|
light_accum[k] += probe_accum[k].rgb * albedo / weight_accum[k];
|
|
}
|
|
}
|
|
}
|
|
|
|
// Store the light in the light texture
|
|
|
|
float lumas[6];
|
|
vec3 light_total = vec3(0);
|
|
|
|
for (int i = 0; i < 6; i++) {
|
|
light_total += light_accum[i];
|
|
lumas[i] = max(light_accum[i].r, max(light_accum[i].g, light_accum[i].b));
|
|
}
|
|
|
|
float luma_total = max(light_total.r, max(light_total.g, light_total.b));
|
|
|
|
uint light_total_rgbe;
|
|
|
|
{
|
|
//compress to RGBE9995 to save space
|
|
|
|
const float pow2to9 = 512.0f;
|
|
const float B = 15.0f;
|
|
const float N = 9.0f;
|
|
const float LN2 = 0.6931471805599453094172321215;
|
|
|
|
float cRed = clamp(light_total.r, 0.0, 65408.0);
|
|
float cGreen = clamp(light_total.g, 0.0, 65408.0);
|
|
float cBlue = clamp(light_total.b, 0.0, 65408.0);
|
|
|
|
float cMax = max(cRed, max(cGreen, cBlue));
|
|
|
|
float expp = max(-B - 1.0f, floor(log(cMax) / LN2)) + 1.0f + B;
|
|
|
|
float sMax = floor((cMax / pow(2.0f, expp - B - N)) + 0.5f);
|
|
|
|
float exps = expp + 1.0f;
|
|
|
|
if (0.0 <= sMax && sMax < pow2to9) {
|
|
exps = expp;
|
|
}
|
|
|
|
float sRed = floor((cRed / pow(2.0f, exps - B - N)) + 0.5f);
|
|
float sGreen = floor((cGreen / pow(2.0f, exps - B - N)) + 0.5f);
|
|
float sBlue = floor((cBlue / pow(2.0f, exps - B - N)) + 0.5f);
|
|
#ifdef MODE_PROCESS_STATIC
|
|
//since its self-save, use RGBE8985
|
|
light_total_rgbe = ((uint(sRed) & 0x1FF) >> 1) | ((uint(sGreen) & 0x1FF) << 8) | (((uint(sBlue) & 0x1FF) >> 1) << 17) | ((uint(exps) & 0x1F) << 25);
|
|
|
|
#else
|
|
light_total_rgbe = (uint(sRed) & 0x1FF) | ((uint(sGreen) & 0x1FF) << 9) | ((uint(sBlue) & 0x1FF) << 18) | ((uint(exps) & 0x1F) << 27);
|
|
#endif
|
|
}
|
|
|
|
#ifdef MODE_PROCESS_DYNAMIC
|
|
|
|
vec4 aniso0;
|
|
aniso0.r = lumas[0] / luma_total;
|
|
aniso0.g = lumas[1] / luma_total;
|
|
aniso0.b = lumas[2] / luma_total;
|
|
aniso0.a = lumas[3] / luma_total;
|
|
|
|
vec2 aniso1;
|
|
aniso1.r = lumas[4] / luma_total;
|
|
aniso1.g = lumas[5] / luma_total;
|
|
|
|
//save to 3D textures
|
|
imageStore(dst_aniso0, positioni, aniso0);
|
|
imageStore(dst_aniso1, positioni, vec4(aniso1, 0.0, 0.0));
|
|
imageStore(dst_light, positioni, uvec4(light_total_rgbe));
|
|
|
|
//also fill neighbours, so light interpolation during the indirect pass works
|
|
|
|
//recover the neighbour list from the leftover bits
|
|
uint neighbours = (voxel_albedo >> 21) | ((voxel_position >> 21) << 11) | ((process_voxels.data[voxel_index].light >> 30) << 22) | ((process_voxels.data[voxel_index].light_aniso >> 30) << 24);
|
|
|
|
const uint max_neighbours = 26;
|
|
const ivec3 neighbour_positions[max_neighbours] = ivec3[](
|
|
ivec3(-1, -1, -1),
|
|
ivec3(-1, -1, 0),
|
|
ivec3(-1, -1, 1),
|
|
ivec3(-1, 0, -1),
|
|
ivec3(-1, 0, 0),
|
|
ivec3(-1, 0, 1),
|
|
ivec3(-1, 1, -1),
|
|
ivec3(-1, 1, 0),
|
|
ivec3(-1, 1, 1),
|
|
ivec3(0, -1, -1),
|
|
ivec3(0, -1, 0),
|
|
ivec3(0, -1, 1),
|
|
ivec3(0, 0, -1),
|
|
ivec3(0, 0, 1),
|
|
ivec3(0, 1, -1),
|
|
ivec3(0, 1, 0),
|
|
ivec3(0, 1, 1),
|
|
ivec3(1, -1, -1),
|
|
ivec3(1, -1, 0),
|
|
ivec3(1, -1, 1),
|
|
ivec3(1, 0, -1),
|
|
ivec3(1, 0, 0),
|
|
ivec3(1, 0, 1),
|
|
ivec3(1, 1, -1),
|
|
ivec3(1, 1, 0),
|
|
ivec3(1, 1, 1));
|
|
|
|
for (uint i = 0; i < max_neighbours; i++) {
|
|
if (bool(neighbours & (1 << i))) {
|
|
ivec3 neighbour_pos = positioni + neighbour_positions[i];
|
|
imageStore(dst_light, neighbour_pos, uvec4(light_total_rgbe));
|
|
imageStore(dst_aniso0, neighbour_pos, aniso0);
|
|
imageStore(dst_aniso1, neighbour_pos, vec4(aniso1, 0.0, 0.0));
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
#ifdef MODE_PROCESS_STATIC
|
|
|
|
//save back the anisotropic
|
|
|
|
uint light = process_voxels.data[voxel_index].light & (3 << 30);
|
|
light |= light_total_rgbe;
|
|
process_voxels.data[voxel_index].light = light; //replace
|
|
|
|
uint light_aniso = process_voxels.data[voxel_index].light_aniso & (3 << 30);
|
|
for (int i = 0; i < 6; i++) {
|
|
light_aniso |= min(31, uint((lumas[i] / luma_total) * 31.0)) << (i * 5);
|
|
}
|
|
|
|
process_voxels.data[voxel_index].light_aniso = light_aniso;
|
|
|
|
#endif
|
|
}
|