godot/servers/visual/rasterizer_rd/shaders/giprobe_write.glsl
2020-02-11 12:03:20 +01:00

354 lines
7.9 KiB
GLSL

[compute]
#version 450
VERSION_DEFINES
layout(local_size_x = 64, local_size_y = 1, local_size_z = 1) in;
#define NO_CHILDREN 0xFFFFFFFF
#define GREY_VEC vec3(0.33333,0.33333,0.33333)
struct CellChildren {
uint children[8];
};
layout(set=0,binding=1,std430) buffer CellChildrenBuffer {
CellChildren data[];
} cell_children;
struct CellData {
uint position; // xyz 10 bits
uint albedo; //rgb albedo
uint emission; //rgb normalized with e as multiplier
uint normal; //RGB normal encoded
};
layout(set=0,binding=2,std430) buffer CellDataBuffer {
CellData data[];
} cell_data;
#define LIGHT_TYPE_DIRECTIONAL 0
#define LIGHT_TYPE_OMNI 1
#define LIGHT_TYPE_SPOT 2
#ifdef MODE_COMPUTE_LIGHT
struct Light {
uint type;
float energy;
float radius;
float attenuation;
vec3 color;
float spot_angle_radians;
vec3 position;
float spot_attenuation;
vec3 direction;
bool has_shadow;
};
layout(set=0,binding=3,std140) uniform Lights {
Light data[MAX_LIGHTS];
} lights;
#endif
layout(push_constant, binding = 0, std430) uniform Params {
ivec3 limits;
uint stack_size;
float emission_scale;
float propagation;
float dynamic_range;
uint light_count;
uint cell_offset;
uint cell_count;
uint pad[2];
} params;
layout(set=0,binding=4,std140) uniform Outputs {
vec4 data[];
} output;
#ifdef MODE_COMPUTE_LIGHT
uint raymarch(float distance,float distance_adv,vec3 from,vec3 direction) {
uint result = NO_CHILDREN;
ivec3 size = ivec3(max(max(params.limits.x,params.limits.y),params.limits.z));
while (distance > -distance_adv) { //use this to avoid precision errors
uint cell = 0;
ivec3 pos = ivec3(from);
if (all(greaterThanEqual(pos,ivec3(0))) && all(lessThan(pos,size))) {
ivec3 ofs = ivec3(0);
ivec3 half_size = size / 2;
for (int i = 0; i < params.stack_size - 1; i++) {
bvec3 greater = greaterThanEqual(pos,ofs+half_size);
ofs += mix(ivec3(0),half_size,greater);
uint child = 0; //wonder if this can be done faster
if (greater.x) {
child|=1;
}
if (greater.y) {
child|=2;
}
if (greater.z) {
child|=4;
}
cell = cell_children.data[cell].children[child];
if (cell == NO_CHILDREN)
break;
half_size >>= ivec3(1);
}
if ( cell != NO_CHILDREN) {
return cell; //found cell!
}
}
from += direction * distance_adv;
distance -= distance_adv;
}
return NO_CHILDREN;
}
bool compute_light_vector(uint light,uint cell, vec3 pos,out float attenuation, out vec3 light_pos) {
if (lights.data[light].type==LIGHT_TYPE_DIRECTIONAL) {
light_pos = pos - lights.data[light].direction * length(vec3(params.limits));
attenuation = 1.0;
} else {
light_pos = lights.data[light].position;
float distance = length(pos - light_pos);
if (distance >= lights.data[light].radius) {
return false;
}
attenuation = pow( clamp( 1.0 - distance / lights.data[light].radius, 0.0001, 1.0), lights.data[light].attenuation );
if (lights.data[light].type==LIGHT_TYPE_SPOT) {
vec3 rel = normalize(pos - light_pos);
float angle = acos(dot(rel,lights.data[light].direction));
if (angle > lights.data[light].spot_angle_radians) {
return false;
}
float d = clamp(angle / lights.data[light].spot_angle_radians, 0, 1);
attenuation *= pow(1.0 - d, lights.data[light].spot_attenuation);
}
}
return true;
}
float get_normal_advance(vec3 p_normal) {
vec3 normal = p_normal;
vec3 unorm = abs(normal);
if ((unorm.x >= unorm.y) && (unorm.x >= unorm.z)) {
// x code
unorm = normal.x > 0.0 ? vec3(1.0, 0.0, 0.0) : vec3(-1.0, 0.0, 0.0);
} else if ((unorm.y > unorm.x) && (unorm.y >= unorm.z)) {
// y code
unorm = normal.y > 0.0 ? vec3(0.0, 1.0, 0.0) : vec3(0.0, -1.0, 0.0);
} else if ((unorm.z > unorm.x) && (unorm.z > unorm.y)) {
// z code
unorm = normal.z > 0.0 ? vec3(0.0, 0.0, 1.0) : vec3(0.0, 0.0, -1.0);
} else {
// oh-no we messed up code
// has to be
unorm = vec3(1.0, 0.0, 0.0);
}
return 1.0 / dot(normal,unorm);
}
#endif
void main() {
uint cell_index = gl_GlobalInvocationID.x;;
if (cell_index >= params.cell_count) {
return;
}
cell_index += params.cell_offset;
uvec3 posu = uvec3(cell_data.data[cell_index].position&0x7FF,(cell_data.data[cell_index].position>>11)&0x3FF,cell_data.data[cell_index].position>>21);
vec4 albedo = unpackUnorm4x8(cell_data.data[cell_index].albedo);
#ifdef MODE_COMPUTE_LIGHT
vec3 pos = vec3(posu) + vec3(0.5);
vec3 emission = vec3(ivec3(cell_data.data[cell_index].emission&0x3FF,(cell_data.data[cell_index].emission>>10)&0x7FF,cell_data.data[cell_index].emission>>21)) * params.emission_scale;
vec4 normal = unpackSnorm4x8(cell_data.data[cell_index].normal);
#ifdef MODE_ANISOTROPIC
vec3 accum[6]=vec3[](vec3(0.0),vec3(0.0),vec3(0.0),vec3(0.0),vec3(0.0),vec3(0.0));
const vec3 accum_dirs[6]=vec3[](vec3(1.0,0.0,0.0),vec3(-1.0,0.0,0.0),vec3(0.0,1.0,0.0),vec3(0.0,-1.0,0.0),vec3(0.0,0.0,1.0),vec3(0.0,0.0,-1.0));
#else
vec3 accum = vec3(0.0);
#endif
for(uint i=0;i<params.light_count;i++) {
float attenuation;
vec3 light_pos;
if (!compute_light_vector(i,cell_index,pos,attenuation,light_pos)) {
continue;
}
vec3 light_dir = pos - light_pos;
float distance = length(light_dir);
light_dir=normalize(light_dir);
if (length(normal.xyz) > 0.2 && dot(normal.xyz,light_dir)>=0) {
continue; //not facing the light
}
if (lights.data[i].has_shadow) {
float distance_adv = get_normal_advance(light_dir);
distance += distance_adv - mod(distance, distance_adv); //make it reach the center of the box always
vec3 from = pos - light_dir * distance; //approximate
from -= sign(light_dir)*0.45; //go near the edge towards the light direction to avoid self occlusion
uint result = raymarch(distance,distance_adv,from,light_dir);
if (result != cell_index) {
continue; //was occluded
}
}
vec3 light = lights.data[i].color * albedo.rgb * attenuation * lights.data[i].energy;
#ifdef MODE_ANISOTROPIC
for(uint j=0;j<6;j++) {
accum[j]+=max(0.0,dot(accum_dir,-light_dir))*light+emission;
}
#else
if (length(normal.xyz) > 0.2) {
accum+=max(0.0,dot(normal.xyz,-light_dir))*light+emission;
} else {
//all directions
accum+=light+emission;
}
#endif
}
#ifdef MODE_ANISOTROPIC
output.data[cell_index*6+0]=vec4(accum[0],0.0);
output.data[cell_index*6+1]=vec4(accum[1],0.0);
output.data[cell_index*6+2]=vec4(accum[2],0.0);
output.data[cell_index*6+3]=vec4(accum[3],0.0);
output.data[cell_index*6+4]=vec4(accum[4],0.0);
output.data[cell_index*6+5]=vec4(accum[5],0.0);
#else
output.data[cell_index]=vec4(accum,0.0);
#endif
#endif //MODE_COMPUTE_LIGHT
#ifdef MODE_UPDATE_MIPMAPS
{
#ifdef MODE_ANISOTROPIC
vec3 light_accum[6] = vec3[](vec3(0.0),vec3(0.0),vec3(0.0),vec3(0.0),vec3(0.0),vec3(0.0));
#else
vec3 light_accum = vec3(0.0);
#endif
float count = 0.0;
for(uint i=0;i<8;i++) {
uint child_index = cell_children.data[cell_index].children[i];
if (child_index==NO_CHILDREN) {
continue;
}
#ifdef MODE_ANISOTROPIC
light_accum[1] += output.data[child_index*6+0].rgb;
light_accum[2] += output.data[child_index*6+1].rgb;
light_accum[3] += output.data[child_index*6+2].rgb;
light_accum[4] += output.data[child_index*6+3].rgb;
light_accum[5] += output.data[child_index*6+4].rgb;
light_accum[6] += output.data[child_index*6+5].rgb;
#else
light_accum += output.data[child_index].rgb;
#endif
count+=1.0;
}
float divisor = mix(8.0,count,params.propagation);
#ifdef MODE_ANISOTROPIC
output.data[cell_index*6+0]=vec4(light_accum[0] / divisor,0.0);
output.data[cell_index*6+1]=vec4(light_accum[1] / divisor,0.0);
output.data[cell_index*6+2]=vec4(light_accum[2] / divisor,0.0);
output.data[cell_index*6+3]=vec4(light_accum[3] / divisor,0.0);
output.data[cell_index*6+4]=vec4(light_accum[4] / divisor,0.0);
output.data[cell_index*6+5]=vec4(light_accum[5] / divisor,0.0);
#else
output.data[cell_index]=vec4(light_accum / divisor,0.0);
#endif
}
#endif
#ifdef MODE_WRITE_TEXTURE
{
}
#endif
}