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uniform sampler2DArray shadowCubeTexture;
uniform sampler2DArray shadowCascadeTexture;
#define LAMPS_LIB
layout(std140) uniform shadow_block {
ShadowData shadows_data[MAX_SHADOW];
ShadowCubeData shadows_cube_data[MAX_SHADOW_CUBE];
ShadowCascadeData shadows_cascade_data[MAX_SHADOW_CASCADE];
};
layout(std140) uniform light_block {
LightData lights_data[MAX_LIGHT];
};
/* type */
#define POINT 0.0
#define SUN 1.0
#define SPOT 2.0
#define AREA_RECT 4.0
/* Used to define the area lamp shape, doesn't directly correspond to a Blender lamp type. */
#define AREA_ELLIPSE 100.0
#if defined(SHADOW_VSM)
#define ShadowSample vec2
#define sample_cube(vec, id) texture_octahedron(shadowCubeTexture, vec4(vec, id)).rg
#define sample_cascade(vec, id) texture(shadowCascadeTexture, vec3(vec, id)).rg
#elif defined(SHADOW_ESM)
#define ShadowSample float
#define sample_cube(vec, id) texture_octahedron(shadowCubeTexture, vec4(vec, id)).r
#define sample_cascade(vec, id) texture(shadowCascadeTexture, vec3(vec, id)).r
#else
#define ShadowSample float
#define sample_cube(vec, id) texture_octahedron(shadowCubeTexture, vec4(vec, id)).r
#define sample_cascade(vec, id) texture(shadowCascadeTexture, vec3(vec, id)).r
#endif
#if defined(SHADOW_VSM)
#define get_depth_delta(dist, s) (dist - s.x)
#else
#define get_depth_delta(dist, s) (dist - s)
#endif
/* ----------------------------------------------------------- */
/* ----------------------- Shadow tests ---------------------- */
/* ----------------------------------------------------------- */
#if defined(SHADOW_VSM)
float shadow_test(ShadowSample moments, float dist, ShadowData sd)
{
float p = 0.0;
if (dist <= moments.x) {
p = 1.0;
}
float variance = moments.y - (moments.x * moments.x);
variance = max(variance, sd.sh_bias / 10.0);
float d = moments.x - dist;
float p_max = variance / (variance + d * d);
/* Now reduce light-bleeding by removing the [0, x] tail and linearly rescaling (x, 1] */
p_max = clamp((p_max - sd.sh_bleed) / (1.0 - sd.sh_bleed), 0.0, 1.0);
return max(p, p_max);
}
#elif defined(SHADOW_ESM)
float shadow_test(ShadowSample z, float dist, ShadowData sd)
{
return saturate(exp(sd.sh_exp * (z - dist + sd.sh_bias)));
}
#else
float shadow_test(ShadowSample z, float dist, ShadowData sd)
{
return step(0, z - dist + sd.sh_bias);
}
#endif
/* ----------------------------------------------------------- */
/* ----------------------- Shadow types ---------------------- */
/* ----------------------------------------------------------- */
float shadow_cubemap(ShadowData sd, ShadowCubeData scd, float texid, vec3 W)
{
vec3 cubevec = W - scd.position.xyz;
float dist = length(cubevec);
cubevec /= dist;
ShadowSample s = sample_cube(cubevec, texid);
return shadow_test(s, dist, sd);
}
float evaluate_cascade(ShadowData sd, mat4 shadowmat, vec3 W, float range, float texid)
{
vec4 shpos = shadowmat * vec4(W, 1.0);
float dist = shpos.z * range;
ShadowSample s = sample_cascade(shpos.xy, texid);
float vis = shadow_test(s, dist, sd);
/* If fragment is out of shadowmap range, do not occlude */
if (shpos.z < 1.0 && shpos.z > 0.0) {
return vis;
}
else {
return 1.0;
}
}
float shadow_cascade(ShadowData sd, int scd_id, float texid, vec3 W)
{
vec4 view_z = vec4(dot(W - cameraPos, cameraForward));
vec4 weights = smoothstep(
shadows_cascade_data[scd_id].split_end_distances,
shadows_cascade_data[scd_id].split_start_distances.yzwx,
view_z);
weights.yzw -= weights.xyz;
vec4 vis = vec4(1.0);
float range = abs(sd.sh_far - sd.sh_near); /* Same factor as in get_cascade_world_distance(). */
/* Branching using (weights > 0.0) is reaally slooow on intel so avoid it for now. */
/* TODO OPTI: Only do 2 samples and blend. */
vis.x = evaluate_cascade(sd, shadows_cascade_data[scd_id].shadowmat[0], W, range, texid + 0);
vis.y = evaluate_cascade(sd, shadows_cascade_data[scd_id].shadowmat[1], W, range, texid + 1);
vis.z = evaluate_cascade(sd, shadows_cascade_data[scd_id].shadowmat[2], W, range, texid + 2);
vis.w = evaluate_cascade(sd, shadows_cascade_data[scd_id].shadowmat[3], W, range, texid + 3);
float weight_sum = dot(vec4(1.0), weights);
if (weight_sum > 0.9999) {
float vis_sum = dot(vec4(1.0), vis * weights);
return vis_sum / weight_sum;
}
else {
float vis_sum = dot(vec4(1.0), vis * step(0.001, weights));
return mix(1.0, vis_sum, weight_sum);
}
}
/* ----------------------------------------------------------- */
/* --------------------- Light Functions --------------------- */
/* ----------------------------------------------------------- */
/* From Frostbite PBR Course
* Distance based attenuation
* http://www.frostbite.com/wp-content/uploads/2014/11/course_notes_moving_frostbite_to_pbr.pdf */
float distance_attenuation(float dist_sqr, float inv_sqr_influence)
{
float factor = dist_sqr * inv_sqr_influence;
float fac = saturate(1.0 - factor * factor);
return fac * fac;
}
float spot_attenuation(LightData ld, vec3 l_vector)
{
float z = dot(ld.l_forward, l_vector.xyz);
vec3 lL = l_vector.xyz / z;
float x = dot(ld.l_right, lL) / ld.l_sizex;
float y = dot(ld.l_up, lL) / ld.l_sizey;
float ellipse = inversesqrt(1.0 + x * x + y * y);
float spotmask = smoothstep(0.0, 1.0, (ellipse - ld.l_spot_size) / ld.l_spot_blend);
return spotmask;
}
float light_visibility(LightData ld, vec3 W,
#ifndef VOLUMETRICS
vec3 viewPosition,
vec3 viewNormal,
#endif
vec4 l_vector)
{
float vis = 1.0;
if (ld.l_type == SPOT) {
vis *= spot_attenuation(ld, l_vector.xyz);
}
if (ld.l_type >= SPOT) {
vis *= step(0.0, -dot(l_vector.xyz, ld.l_forward));
}
if (ld.l_type != SUN) {
vis *= distance_attenuation(l_vector.w * l_vector.w, ld.l_influence);
}
#if !defined(VOLUMETRICS) || defined(VOLUME_SHADOW)
/* shadowing */
if (ld.l_shadowid >= 0.0 && vis > 0.001) {
ShadowData data = shadows_data[int(ld.l_shadowid)];
if (ld.l_type == SUN) {
vis *= shadow_cascade(
data, int(data.sh_data_start),
data.sh_tex_start, W);
}
else {
vis *= shadow_cubemap(
data, shadows_cube_data[int(data.sh_data_start)],
data.sh_tex_start, W);
}
#ifndef VOLUMETRICS
/* Only compute if not already in shadow. */
if (data.sh_contact_dist > 0.0) {
vec4 L = (ld.l_type != SUN) ? l_vector : vec4(-ld.l_forward, 1.0);
float trace_distance = (ld.l_type != SUN) ? min(data.sh_contact_dist, l_vector.w) : data.sh_contact_dist;
vec3 T, B;
make_orthonormal_basis(L.xyz / L.w, T, B);
vec4 rand = texelfetch_noise_tex(gl_FragCoord.xy);
rand.zw *= fast_sqrt(rand.y) * data.sh_contact_spread;
/* We use the full l_vector.xyz so that the spread is minimize
* if the shading point is further away from the light source */
vec3 ray_dir = L.xyz + T * rand.z + B * rand.w;
ray_dir = transform_direction(ViewMatrix, ray_dir);
ray_dir = normalize(ray_dir);
vec3 ray_ori = viewPosition;
if (dot(viewNormal, ray_dir) <= 0.0) {
return vis;
}
float bias = 0.5; /* Constant Bias */
bias += 1.0 - abs(dot(viewNormal, ray_dir)); /* Angle dependent bias */
bias *= gl_FrontFacing ? data.sh_contact_offset : -data.sh_contact_offset;
vec3 nor_bias = viewNormal * bias;
ray_ori += nor_bias;
ray_dir *= trace_distance;
ray_dir -= nor_bias;
vec3 hit_pos = raycast(-1, ray_ori, ray_dir, data.sh_contact_thickness, rand.x,
0.1, 0.001, false);
if (hit_pos.z > 0.0) {
hit_pos = get_view_space_from_depth(hit_pos.xy, hit_pos.z);
float hit_dist = distance(viewPosition, hit_pos);
float dist_ratio = hit_dist / trace_distance;
return vis * saturate(dist_ratio * dist_ratio * dist_ratio);
}
}
#endif
}
#endif
return vis;
}
#ifdef USE_LTC
float light_diffuse(LightData ld, vec3 N, vec3 V, vec4 l_vector)
{
if (ld.l_type == AREA_RECT) {
vec3 corners[4];
corners[0] = normalize((l_vector.xyz + ld.l_right * -ld.l_sizex) + ld.l_up * ld.l_sizey);
corners[1] = normalize((l_vector.xyz + ld.l_right * -ld.l_sizex) + ld.l_up * -ld.l_sizey);
corners[2] = normalize((l_vector.xyz + ld.l_right * ld.l_sizex) + ld.l_up * -ld.l_sizey);
corners[3] = normalize((l_vector.xyz + ld.l_right * ld.l_sizex) + ld.l_up * ld.l_sizey);
return ltc_evaluate_quad(corners, N);
}
else if (ld.l_type == AREA_ELLIPSE) {
vec3 points[3];
points[0] = (l_vector.xyz + ld.l_right * -ld.l_sizex) + ld.l_up * -ld.l_sizey;
points[1] = (l_vector.xyz + ld.l_right * ld.l_sizex) + ld.l_up * -ld.l_sizey;
points[2] = (l_vector.xyz + ld.l_right * ld.l_sizex) + ld.l_up * ld.l_sizey;
return ltc_evaluate_disk(N, V, mat3(1.0), points);
}
else {
float radius = ld.l_radius;
radius /= (ld.l_type == SUN) ? 1.0 : l_vector.w;
vec3 L = (ld.l_type == SUN) ? -ld.l_forward : (l_vector.xyz / l_vector.w);
return ltc_evaluate_disk_simple(radius, dot(N, L));
}
}
float light_specular(LightData ld, vec4 ltc_mat, vec3 N, vec3 V, vec4 l_vector)
{
if (ld.l_type == AREA_RECT) {
vec3 corners[4];
corners[0] = (l_vector.xyz + ld.l_right * -ld.l_sizex) + ld.l_up * ld.l_sizey;
corners[1] = (l_vector.xyz + ld.l_right * -ld.l_sizex) + ld.l_up * -ld.l_sizey;
corners[2] = (l_vector.xyz + ld.l_right * ld.l_sizex) + ld.l_up * -ld.l_sizey;
corners[3] = (l_vector.xyz + ld.l_right * ld.l_sizex) + ld.l_up * ld.l_sizey;
ltc_transform_quad(N, V, ltc_matrix(ltc_mat), corners);
return ltc_evaluate_quad(corners, vec3(0.0, 0.0, 1.0));
}
else {
bool is_ellipse = (ld.l_type == AREA_ELLIPSE);
float radius_x = is_ellipse ? ld.l_sizex : ld.l_radius;
float radius_y = is_ellipse ? ld.l_sizey : ld.l_radius;
vec3 L = (ld.l_type == SUN) ? -ld.l_forward : l_vector.xyz;
vec3 Px = ld.l_right;
vec3 Py = ld.l_up;
if (ld.l_type == SPOT || ld.l_type == POINT) {
make_orthonormal_basis(l_vector.xyz / l_vector.w, Px, Py);
}
vec3 points[3];
points[0] = (L + Px * -radius_x) + Py * -radius_y;
points[1] = (L + Px * radius_x) + Py * -radius_y;
points[2] = (L + Px * radius_x) + Py * radius_y;
return ltc_evaluate_disk(N, V, ltc_matrix(ltc_mat), points);
}
}
#endif
#define MAX_SSS_SAMPLES 65
#define SSS_LUT_SIZE 64.0
#define SSS_LUT_SCALE ((SSS_LUT_SIZE - 1.0) / float(SSS_LUT_SIZE))
#define SSS_LUT_BIAS (0.5 / float(SSS_LUT_SIZE))
#ifdef USE_TRANSLUCENCY
layout(std140) uniform sssProfile {
vec4 kernel[MAX_SSS_SAMPLES];
vec4 radii_max_radius;
int sss_samples;
};
uniform sampler1D sssTexProfile;
vec3 sss_profile(float s) {
s /= radii_max_radius.w;
return texture(sssTexProfile, saturate(s) * SSS_LUT_SCALE + SSS_LUT_BIAS).rgb;
}
#endif
vec3 light_translucent(LightData ld, vec3 W, vec3 N, vec4 l_vector, float scale)
{
#if !defined(USE_TRANSLUCENCY) || defined(VOLUMETRICS)
return vec3(0.0);
#else
vec3 vis = vec3(1.0);
if (ld.l_type == SPOT) {
vis *= spot_attenuation(ld, l_vector.xyz);
}
if (ld.l_type >= SPOT) {
vis *= step(0.0, -dot(l_vector.xyz, ld.l_forward));
}
if (ld.l_type != SUN) {
vis *= distance_attenuation(l_vector.w * l_vector.w, ld.l_influence);
}
/* Only shadowed light can produce translucency */
if (ld.l_shadowid >= 0.0 && vis.x > 0.001) {
ShadowData data = shadows_data[int(ld.l_shadowid)];
float delta;
vec4 L = (ld.l_type != SUN) ? l_vector : vec4(-ld.l_forward, 1.0);
vec3 T, B;
make_orthonormal_basis(L.xyz / L.w, T, B);
vec4 rand = texelfetch_noise_tex(gl_FragCoord.xy);
rand.zw *= fast_sqrt(rand.y) * data.sh_blur;
/* We use the full l_vector.xyz so that the spread is minimize
* if the shading point is further away from the light source */
W = W + T * rand.z + B * rand.w;
if (ld.l_type == SUN) {
int scd_id = int(data.sh_data_start);
vec4 view_z = vec4(dot(W - cameraPos, cameraForward));
vec4 weights = step(shadows_cascade_data[scd_id].split_end_distances, view_z);
float id = abs(4.0 - dot(weights, weights));
if (id > 3.0) {
return vec3(0.0);
}
float range = abs(data.sh_far - data.sh_near); /* Same factor as in get_cascade_world_distance(). */
vec4 shpos = shadows_cascade_data[scd_id].shadowmat[int(id)] * vec4(W, 1.0);
float dist = shpos.z * range;
if (shpos.z > 1.0 || shpos.z < 0.0) {
return vec3(0.0);
}
ShadowSample s = sample_cascade(shpos.xy, data.sh_tex_start + id);
delta = get_depth_delta(dist, s);
}
else {
vec3 cubevec = W - shadows_cube_data[int(data.sh_data_start)].position.xyz;
float dist = length(cubevec);
cubevec /= dist;
ShadowSample s = sample_cube(cubevec, data.sh_tex_start);
delta = get_depth_delta(dist, s);
}
/* XXX : Removing Area Power. */
/* TODO : put this out of the shader. */
float falloff;
if (ld.l_type == AREA_RECT || ld.l_type == AREA_ELLIPSE) {
vis *= (ld.l_sizex * ld.l_sizey * 4.0 * M_PI) * (1.0 / 80.0);
if (ld.l_type == AREA_ELLIPSE) {
vis *= M_PI * 0.25;
}
vis *= 0.3 * 20.0 * max(0.0, dot(-ld.l_forward, l_vector.xyz / l_vector.w)); /* XXX ad hoc, empirical */
vis /= (l_vector.w * l_vector.w);
falloff = dot(N, l_vector.xyz / l_vector.w);
}
else if (ld.l_type == SUN) {
vis /= 1.0f + (ld.l_radius * ld.l_radius * 0.5f);
vis *= ld.l_radius * ld.l_radius * M_PI; /* Removing area light power*/
vis *= M_2PI * 0.78; /* Matching cycles with point light. */
vis *= 0.082; /* XXX ad hoc, empirical */
falloff = dot(N, -ld.l_forward);
}
else {
vis *= (4.0 * ld.l_radius * ld.l_radius) * (1.0 /10.0);
vis *= 1.5; /* XXX ad hoc, empirical */
vis /= (l_vector.w * l_vector.w);
falloff = dot(N, l_vector.xyz / l_vector.w);
}
// vis *= M_1_PI; /* Normalize */
/* Applying profile */
vis *= sss_profile(abs(delta) / scale);
/* No transmittance at grazing angle (hide artifacts) */
vis *= saturate(falloff * 2.0);
}
else {
vis = vec3(0.0);
}
return vis;
#endif
}
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