veloren/assets/voxygen/shaders/terrain-frag.glsl
2020-04-24 16:12:20 +02:00

100 lines
4.4 KiB
GLSL

#version 330 core
#include <globals.glsl>
in vec3 f_pos;
flat in uint f_pos_norm;
in float f_alt;
in vec4 f_shadow;
in vec3 f_col;
in float f_light;
out vec4 tgt_color;
#include <sky.glsl>
#include <light.glsl>
#include <lod.glsl>
void main() {
// First 3 normals are negative, next 3 are positive
vec3 normals[6] = vec3[](vec3(-1,0,0), vec3(1,0,0), vec3(0,-1,0), vec3(0,1,0), vec3(0,0,-1), vec3(0,0,1));
// TODO: last 3 bits in v_pos_norm should be a number between 0 and 5, rather than 0-2 and a direction.
uint norm_axis = (f_pos_norm >> 30) & 0x3u;
// Increase array access by 3 to access positive values
uint norm_dir = ((f_pos_norm >> 29) & 0x1u) * 3u;
// Use an array to avoid conditional branching
vec3 f_norm = normals[(f_pos_norm >> 29) & 0x7u];
vec3 cam_to_frag = normalize(f_pos - cam_pos.xyz);
// vec4 vert_pos4 = view_mat * vec4(f_pos, 1.0);
// vec3 view_dir = normalize(-vec3(vert_pos4)/* / vert_pos4.w*/);
vec3 view_dir = -cam_to_frag;
// vec3 view_dir = normalize(f_pos - cam_pos.xyz);
vec3 sun_dir = get_sun_dir(time_of_day.x);
vec3 moon_dir = get_moon_dir(time_of_day.x);
// float sun_light = get_sun_brightness(sun_dir);
// float moon_light = get_moon_brightness(moon_dir);
/* float sun_shade_frac = horizon_at(f_pos, sun_dir);
float moon_shade_frac = horizon_at(f_pos, moon_dir); */
float sun_shade_frac = horizon_at2(f_shadow, f_alt, f_pos, sun_dir);
float moon_shade_frac = horizon_at2(f_shadow, f_alt, f_pos, moon_dir);
// Globbal illumination "estimate" used to light the faces of voxels which are parallel to the sun or moon (which is a very common occurrence).
// Will be attenuated by k_d, which is assumed to carry any additional ambient occlusion information (e.g. about shadowing).
// float ambient_sides = clamp(mix(0.5, 0.0, abs(dot(-f_norm, sun_dir)) * 10000.0), 0.0, 0.5);
// NOTE: current assumption is that moon and sun shouldn't be out at the sae time.
// This assumption is (or can at least easily be) wrong, but if we pretend it's true we avoids having to explicitly pass in a separate shadow
// for the sun and moon (since they have different brightnesses / colors so the shadows shouldn't attenuate equally).
float shade_frac = /*1.0;*/sun_shade_frac + moon_shade_frac;
vec3 surf_color = /*srgb_to_linear*/(f_col);
float alpha = 1.0;
const float n2 = 1.01;
const float R_s = pow((1.0 - n2) / (1.0 + n2), 2);
vec3 k_a = vec3(1.0);
vec3 k_d = vec3(1.0);
vec3 k_s = vec3(R_s);
float max_light = 0.0;
vec3 emitted_light, reflected_light;
float point_shadow = shadow_at(f_pos, f_norm);
max_light += get_sun_diffuse2(f_norm, /*time_of_day.x, */sun_dir, moon_dir, view_dir, k_a/* * (shade_frac * 0.5 + light_frac * 0.5)*/, k_d, k_s, alpha, emitted_light, reflected_light);
emitted_light *= f_light * point_shadow;
reflected_light *= f_light * point_shadow * shade_frac;
max_light += lights_at(f_pos, f_norm, view_dir, k_a, k_d, k_s, alpha, emitted_light, reflected_light);
/* vec3 point_light = light_at(f_pos, f_norm);
emitted_light += point_light;
reflected_light += point_light; */
// float point_shadow = shadow_at(f_pos, f_norm);
// vec3 point_light = light_at(f_pos, f_norm);
// vec3 light, diffuse_light, ambient_light;
// get_sun_diffuse(f_norm, time_of_day.x, cam_to_frag, k_a * f_light, k_d * f_light, k_s * f_light, alpha, emitted_light, reflected_light);
// get_sun_diffuse(f_norm, time_of_day.x, light, diffuse_light, ambient_light, 1.0);
// float point_shadow = shadow_at(f_pos, f_norm);
// diffuse_light *= f_light * point_shadow;
// ambient_light *= f_light * point_shadow;
// vec3 point_light = light_at(f_pos, f_norm);
// light += point_light;
// diffuse_light += point_light;
// reflected_light += point_light;
// reflected_light += light_reflection_factor(norm, cam_to_frag, , vec3 k_d, vec3 k_s, float alpha) {
// light_reflection_factorplight_reflection_factor
// vec3 surf_color = illuminate(srgb_to_linear(f_col), light, diffuse_light, ambient_light);
surf_color = illuminate(f_col * emitted_light, f_col * reflected_light);
float fog_level = fog(f_pos.xyz, focus_pos.xyz, medium.x);
vec4 clouds;
vec3 fog_color = get_sky_color(cam_to_frag/*view_dir*/, time_of_day.x, cam_pos.xyz, f_pos, 1.0, true, clouds);
// vec3 color = surf_color;
vec3 color = mix(mix(surf_color, fog_color, fog_level), clouds.rgb, clouds.a);
tgt_color = vec4(color, 1.0);
}