Lubos Lenco
114 lines
3.0 KiB
GLSL
114 lines
3.0 KiB
GLSL
#version 450
|
|
|
|
uniform sampler2D tex;
|
|
uniform sampler2D gbufferD;
|
|
uniform sampler2D gbuffer0;
|
|
uniform sampler2D gbuffer1;
|
|
uniform mat4 P;
|
|
uniform mat3 V3;
|
|
uniform vec2 camera_proj;
|
|
|
|
#include "std/math.glsl"
|
|
#include "std/gbuffer.glsl"
|
|
|
|
in vec3 view_ray;
|
|
in vec2 tex_coord;
|
|
out vec4 frag_color;
|
|
|
|
const float ssr_ray_step = 0.04;
|
|
const float ssr_min_ray_step = 0.05;
|
|
const float ssr_search_dist = 5.0;
|
|
const float ssr_falloff_exp = 5.0;
|
|
const float ssr_jitter = 0.6;
|
|
const int num_binary_search_steps = 7;
|
|
const int max_steps = 18;
|
|
|
|
vec3 hit_coord;
|
|
float depth;
|
|
|
|
vec2 get_projected_coord(const vec3 hit) {
|
|
vec4 projected_coord = mul(vec4(hit, 1.0), P);
|
|
projected_coord.xy /= projected_coord.w;
|
|
projected_coord.xy = projected_coord.xy * 0.5 + 0.5;
|
|
#ifdef GLSL
|
|
#else
|
|
projected_coord.y = 1.0 - projected_coord.y;
|
|
#endif
|
|
return projected_coord.xy;
|
|
}
|
|
|
|
float get_delta_depth(const vec3 hit) {
|
|
depth = textureLod(gbufferD, get_projected_coord(hit), 0.0).r * 2.0 - 1.0;
|
|
vec3 view_pos = get_pos_view(view_ray, depth, camera_proj);
|
|
return view_pos.z - hit.z;
|
|
}
|
|
|
|
vec4 binary_search(vec3 dir) {
|
|
float ddepth;
|
|
vec3 start = hit_coord;
|
|
for (int i = 0; i < num_binary_search_steps; i++) {
|
|
dir *= 0.5;
|
|
hit_coord -= dir;
|
|
ddepth = get_delta_depth(hit_coord);
|
|
if (ddepth < 0.0) hit_coord += dir;
|
|
}
|
|
// Ugly discard of hits too far away
|
|
if (abs(ddepth) > ssr_search_dist / 500) return vec4(0.0, 0.0, 0.0, 0.0);
|
|
return vec4(get_projected_coord(hit_coord), 0.0, 1.0);
|
|
}
|
|
|
|
vec4 ray_cast(vec3 dir) {
|
|
dir *= ssr_ray_step;
|
|
for (int i = 0; i < max_steps; i++) {
|
|
hit_coord += dir;
|
|
if (get_delta_depth(hit_coord) > 0.0) return binary_search(dir);
|
|
}
|
|
return vec4(0.0, 0.0, 0.0, 0.0);
|
|
}
|
|
|
|
void main() {
|
|
vec4 g0 = textureLod(gbuffer0, tex_coord, 0.0);
|
|
float roughness = g0.b;
|
|
if (roughness == 1.0) {
|
|
frag_color.rgb = vec3(0.0, 0.0, 0.0);
|
|
return;
|
|
}
|
|
|
|
float d = textureLod(gbufferD, tex_coord, 0.0).r * 2.0 - 1.0;
|
|
if (d == 1.0) {
|
|
frag_color.rgb = vec3(0.0, 0.0, 0.0);
|
|
return;
|
|
}
|
|
|
|
vec2 enc = g0.rg;
|
|
vec3 n;
|
|
n.z = 1.0 - abs(enc.x) - abs(enc.y);
|
|
n.xy = n.z >= 0.0 ? enc.xy : octahedron_wrap(enc.xy);
|
|
n = normalize(n);
|
|
|
|
vec3 view_normal = mul(n, V3);
|
|
vec3 view_pos = get_pos_view(view_ray, d, camera_proj);
|
|
vec3 reflected = normalize(reflect(view_pos, view_normal));
|
|
hit_coord = view_pos;
|
|
|
|
vec3 dir = reflected * (1.0 - rand(tex_coord) * ssr_jitter * roughness) * 2.0;
|
|
// * max(ssr_min_ray_step, -view_pos.z)
|
|
vec4 coords = ray_cast(dir);
|
|
|
|
vec2 delta_coords = abs(vec2(0.5, 0.5) - coords.xy);
|
|
float screen_edge_factor = clamp(1.0 - (delta_coords.x + delta_coords.y), 0.0, 1.0);
|
|
|
|
float reflectivity = 1.0 - roughness;
|
|
float intensity = pow(reflectivity, ssr_falloff_exp) *
|
|
screen_edge_factor *
|
|
clamp(-reflected.z, 0.0, 1.0) *
|
|
clamp((ssr_search_dist - length(view_pos - hit_coord)) *
|
|
(1.0 / ssr_search_dist), 0.0, 1.0) *
|
|
coords.w;
|
|
|
|
intensity = clamp(intensity, 0.0, 1.0);
|
|
vec3 reflcol = textureLod(tex, coords.xy, 0.0).rgb;
|
|
reflcol = clamp(reflcol, 0.0, 1.0);
|
|
frag_color.rgb = reflcol * intensity * 0.5;
|
|
}
|