godot/servers/visual/rasterizer_rd/shaders/scene_forward.glsl

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/* clang-format off */
[vertex]
/* clang-format on */
#version 450
/* clang-format off */
VERSION_DEFINES
/* clang-format on */
/* INPUT ATTRIBS */
layout(location = 0) in vec3 vertex_attrib;
/* clang-format on */
layout(location = 1) in vec3 normal_attrib;
#if defined(TANGENT_USED) || defined(NORMALMAP_USED) || defined(LIGHT_ANISOTROPY_USED)
layout(location = 2) in vec4 tangent_attrib;
#endif
#if defined(COLOR_USED)
layout(location = 3) in vec4 color_attrib;
#endif
#if defined(UV_USED)
layout(location = 4) in vec2 uv_attrib;
#endif
#if defined(UV2_USED) || defined(USE_LIGHTMAP)
layout(location = 5) in vec2 uv2_attrib;
#endif
layout(location = 6) in uvec4 bone_attrib; // always bound, even if unused
/* Varyings */
out vec3 vertex_interp;
out vec3 normal_interp;
#if defined(COLOR_USED)
out vec4 color_interp;
#endif
#if defined(UV2_USED) || defined(USE_LIGHTMAP)
out vec2 uv_interp;
#endif
//uv2 may be used for lightmapping, so always pass.
#if !defined(MODE_RENDER_DEPTH)
out vec2 uv2_interp;
#endif
#if defined(TANGENT_USED) || defined(NORMALMAP_USED) || defined(LIGHT_ANISOTROPY_USED)
out vec3 tangent_interp;
out vec3 binormal_interp;
#endif
#ifdef USE_MATERIAL_UNIFORMS
layout(set = 2, binding = 0, std140) uniform MaterialUniforms {
/* clang-format off */
MATERIAL_UNIFORMS
/* clang-format on */
} material;
#endif
/* clang-format off */
VERTEX_SHADER_GLOBALS
/* clang-format on */
// FIXME: This triggers a Mesa bug that breaks rendering, so disabled for now.
// See GH-13450 and https://bugs.freedesktop.org/show_bug.cgi?id=100316
//invariant gl_Position;
void main() {
vec3 vertex = vertex_attrib;
mat4 world_matrix = instance_data.transform;
mat3 world_normal_matrix= instance_data.normal_transform;
vec3 normal = normal_attrib;
#if defined(TANGENT_USED) || defined(NORMALMAP_USED) || defined(LIGHT_ANISOTROPY_USED)
vec3 tangent = tangent_attrib.xyz;
float binormalf = tangent_attrib.a;
#endif
#if defined(COLOR_USED)
color_interp = color_attrib;
#endif
#if defined(TANGENT_USED) || defined(NORMALMAP_USED) || defined(LIGHT_ANISOTROPY_USED)
vec3 binormal = normalize(cross(normal, tangent) * binormalf);
#endif
#if defined(UV_USED)
uv_interp = uv_attrib;
#endif
#if defined(UV2_USED) || defined(USE_LIGHTMAP)
uv2_interp = uv2_attrib;
#endif
#ifdef USE_OVERRIDE_POSITION
vec4 position;
#endif
vec4 instance_custom = vec4(0.0);
mat4 projection_matrix = scene_data.projection_matrix;
//using world coordinates
#if !defined(SKIP_TRANSFORM_USED) && defined(VERTEX_WORLD_COORDS_USED)
vertex = (world_matrix * vec4(vertex,1.0)).xyz;
normal = world_normal_matrix * normal;
#if defined(TANGENT_USED) || defined(NORMALMAP_USED) || defined(LIGHT_ANISOTROPY_USED)
tangent = world_normal_matrix * tangent;
binormal = world_normal_matrix * binormal;
#endif
#endif
float roughness = 1.0;
mat4 modelview = scene_data.inv_camera_matrix * instance_data.transform;
mat3 modelview_normal = mat3(scene_data.inv_camera_matrix) * instance_data.normal_transform;
{
/* clang-format off */
VERTEX_SHADER_CODE
/* clang-format on */
}
// using local coordinates (default)
#if !defined(SKIP_TRANSFORM_USED) && !defined(VERTEX_WORLD_COORDS_USED)
vertex = (modelview * vec4(vertex,1.0)).xyz;
normal = modelview_normal * normal;
#endif
#if defined(TANGENT_USED) || defined(NORMALMAP_USED) || defined(LIGHT_ANISOTROPY_USED)
binormal = modelview_normal * binormal;
tangent = modelview_normal * tangent;
#endif
#endif
//using world coordinates
#if !defined(SKIP_TRANSFORM_USED) && defined(VERTEX_WORLD_COORDS_USED)
vertex = (scene_data.inv_camera_matrix * vec4(vertex,1.0)).xyz;
normal = mat3(scene_data.inverse_normal_matrix) * normal;
#if defined(TANGENT_USED) || defined(NORMALMAP_USED) || defined(LIGHT_ANISOTROPY_USED)
binormal = mat3(scene_data.camera_inverse_binormal_matrix) * binormal;
tangent = mat3(scene_data.camera_inverse_tangent_matrix) * tangent;
#endif
#endif
vertex_interp = vertex;
normal_interp = normal;
#if defined(TANGENT_USED) || defined(NORMALMAP_USED) || defined(LIGHT_ANISOTROPY_USED)
tangent_interp = tangent;
binormal_interp = binormal;
#endif
#ifdef MODE_RENDER_DEPTH
float z_ofs = scene_data.z_offset;
z_ofs += (1.0 - abs(normal_interp.z)) * scene_data.z_slope_scale;
vertex_interp.z -= z_ofs;
#endif //MODE_RENDER_DEPTH
#ifdef USE_OVERRIDE_POSITION
gl_Position = position;
#else
gl_Position = projection_matrix * vec4(vertex_interp, 1.0);
#endif
}
/* clang-format off */
[fragment]
/* clang-format on */
#version 450
/* clang-format off */
VERSION_DEFINES
/* clang-format on */
/* Varyings */
#if defined(COLOR_USED)
in vec4 color_interp;
#endif
#if defined(UV_USED)
in vec2 uv_interp;
#endif
#if defined(UV2_USED) || defined(USE_LIGHTMAP)
in vec2 uv2_interp;
#endif
#if defined(TANGENT_USED) || defined(NORMALMAP_USED) || defined(LIGHT_ANISOTROPY_USED)
in vec3 tangent_interp;
in vec3 binormal_interp;
#endif
in highp vec3 vertex_interp;
in vec3 normal_interp;
//defines to keep compatibility with vertex
#define world_matrix instance_data.transform;
#define world_normal_matrix instance_data.normal_transform;
#define projection_matrix scene_data.projection_matrix;
#ifdef USE_MATERIAL_UNIFORMS
layout(set = 2, binding = 0, std140) uniform MaterialUniforms {
/* clang-format off */
MATERIAL_UNIFORMS
/* clang-format on */
} material;
#endif
/* clang-format off */
FRAGMENT_SHADER_GLOBALS
/* clang-format on */
#ifdef MODE_MULTIPLE_RENDER_TARGETS
layout(location = 0) out vec4 diffuse_buffer; //diffuse (rgb) and roughness
layout(location = 1) out vec4 specular_buffer; //specular and SSS (subsurface scatter)
#else
layout(location = 0) out vec4 frag_color;
#endif
// This returns the G_GGX function divided by 2 cos_theta_m, where in practice cos_theta_m is either N.L or N.V.
// We're dividing this factor off because the overall term we'll end up looks like
// (see, for example, the first unnumbered equation in B. Burley, "Physically Based Shading at Disney", SIGGRAPH 2012):
//
// F(L.V) D(N.H) G(N.L) G(N.V) / (4 N.L N.V)
//
// We're basically regouping this as
//
// F(L.V) D(N.H) [G(N.L)/(2 N.L)] [G(N.V) / (2 N.V)]
//
// and thus, this function implements the [G(N.m)/(2 N.m)] part with m = L or V.
//
// The contents of the D and G (G1) functions (GGX) are taken from
// E. Heitz, "Understanding the Masking-Shadowing Function in Microfacet-Based BRDFs", J. Comp. Graph. Tech. 3 (2) (2014).
// Eqns 71-72 and 85-86 (see also Eqns 43 and 80).
float G_GGX_2cos(float cos_theta_m, float alpha) {
// Schlick's approximation
// C. Schlick, "An Inexpensive BRDF Model for Physically-based Rendering", Computer Graphics Forum. 13 (3): 233 (1994)
// Eq. (19), although see Heitz (2014) the about the problems with his derivation.
// It nevertheless approximates GGX well with k = alpha/2.
float k = 0.5 * alpha;
return 0.5 / (cos_theta_m * (1.0 - k) + k);
// float cos2 = cos_theta_m * cos_theta_m;
// float sin2 = (1.0 - cos2);
// return 1.0 / (cos_theta_m + sqrt(cos2 + alpha * alpha * sin2));
}
float D_GGX(float cos_theta_m, float alpha) {
float alpha2 = alpha * alpha;
float d = 1.0 + (alpha2 - 1.0) * cos_theta_m * cos_theta_m;
return alpha2 / (M_PI * d * d);
}
float G_GGX_anisotropic_2cos(float cos_theta_m, float alpha_x, float alpha_y, float cos_phi, float sin_phi) {
float cos2 = cos_theta_m * cos_theta_m;
float sin2 = (1.0 - cos2);
float s_x = alpha_x * cos_phi;
float s_y = alpha_y * sin_phi;
return 1.0 / max(cos_theta_m + sqrt(cos2 + (s_x * s_x + s_y * s_y) * sin2), 0.001);
}
float D_GGX_anisotropic(float cos_theta_m, float alpha_x, float alpha_y, float cos_phi, float sin_phi) {
float cos2 = cos_theta_m * cos_theta_m;
float sin2 = (1.0 - cos2);
float r_x = cos_phi / alpha_x;
float r_y = sin_phi / alpha_y;
float d = cos2 + sin2 * (r_x * r_x + r_y * r_y);
return 1.0 / max(M_PI * alpha_x * alpha_y * d * d, 0.001);
}
float SchlickFresnel(float u) {
float m = 1.0 - u;
float m2 = m * m;
return m2 * m2 * m; // pow(m,5)
}
float GTR1(float NdotH, float a) {
if (a >= 1.0) return 1.0 / M_PI;
float a2 = a * a;
float t = 1.0 + (a2 - 1.0) * NdotH * NdotH;
return (a2 - 1.0) / (M_PI * log(a2) * t);
}
vec3 F0(float metallic, float specular, vec3 albedo) {
float dielectric = 0.16 * specular * specular;
// use albedo * metallic as colored specular reflectance at 0 angle for metallic materials;
// see https://google.github.io/filament/Filament.md.html
return mix(vec3(dielectric), albedo, vec3(metallic));
}
void light_compute(vec3 N, vec3 L, vec3 V, vec3 B, vec3 T, vec3 light_color, vec3 attenuation, vec3 diffuse_color, vec3 transmission, float specular_blob_intensity, float roughness, float metallic, float specular, float rim, float rim_tint, float clearcoat, float clearcoat_gloss, float anisotropy, inout vec3 diffuse_light, inout vec3 specular_light, inout float alpha) {
#if defined(USE_LIGHT_SHADER_CODE)
// light is written by the light shader
vec3 normal = N;
vec3 albedo = diffuse_color;
vec3 light = L;
vec3 view = V;
/* clang-format off */
LIGHT_SHADER_CODE
/* clang-format on */
#else
float NdotL = dot(N, L);
float cNdotL = max(NdotL, 0.0); // clamped NdotL
float NdotV = dot(N, V);
float cNdotV = max(NdotV, 0.0);
#if defined(DIFFUSE_BURLEY) || defined(SPECULAR_BLINN) || defined(SPECULAR_SCHLICK_GGX) || defined(LIGHT_USE_CLEARCOAT)
vec3 H = normalize(V + L);
#endif
#if defined(SPECULAR_BLINN) || defined(SPECULAR_SCHLICK_GGX) || defined(LIGHT_USE_CLEARCOAT)
float cNdotH = max(dot(N, H), 0.0);
#endif
#if defined(DIFFUSE_BURLEY) || defined(SPECULAR_SCHLICK_GGX) || defined(LIGHT_USE_CLEARCOAT)
float cLdotH = max(dot(L, H), 0.0);
#endif
if (metallic < 1.0) {
#if defined(DIFFUSE_OREN_NAYAR)
vec3 diffuse_brdf_NL;
#else
float diffuse_brdf_NL; // BRDF times N.L for calculating diffuse radiance
#endif
#if defined(DIFFUSE_LAMBERT_WRAP)
// energy conserving lambert wrap shader
diffuse_brdf_NL = max(0.0, (NdotL + roughness) / ((1.0 + roughness) * (1.0 + roughness)));
#elif defined(DIFFUSE_OREN_NAYAR)
{
// see http://mimosa-pudica.net/improved-oren-nayar.html
float LdotV = dot(L, V);
float s = LdotV - NdotL * NdotV;
float t = mix(1.0, max(NdotL, NdotV), step(0.0, s));
float sigma2 = roughness * roughness; // TODO: this needs checking
vec3 A = 1.0 + sigma2 * (-0.5 / (sigma2 + 0.33) + 0.17 * diffuse_color / (sigma2 + 0.13));
float B = 0.45 * sigma2 / (sigma2 + 0.09);
diffuse_brdf_NL = cNdotL * (A + vec3(B) * s / t) * (1.0 / M_PI);
}
#elif defined(DIFFUSE_TOON)
diffuse_brdf_NL = smoothstep(-roughness, max(roughness, 0.01), NdotL);
#elif defined(DIFFUSE_BURLEY)
{
float FD90_minus_1 = 2.0 * cLdotH * cLdotH * roughness - 0.5;
float FdV = 1.0 + FD90_minus_1 * SchlickFresnel(cNdotV);
float FdL = 1.0 + FD90_minus_1 * SchlickFresnel(cNdotL);
diffuse_brdf_NL = (1.0 / M_PI) * FdV * FdL * cNdotL;
/*
float energyBias = mix(roughness, 0.0, 0.5);
float energyFactor = mix(roughness, 1.0, 1.0 / 1.51);
float fd90 = energyBias + 2.0 * VoH * VoH * roughness;
float f0 = 1.0;
float lightScatter = f0 + (fd90 - f0) * pow(1.0 - cNdotL, 5.0);
float viewScatter = f0 + (fd90 - f0) * pow(1.0 - cNdotV, 5.0);
diffuse_brdf_NL = lightScatter * viewScatter * energyFactor;
*/
}
#else
// lambert
diffuse_brdf_NL = cNdotL * (1.0 / M_PI);
#endif
diffuse_light += light_color * diffuse_color * diffuse_brdf_NL * attenuation;
#if defined(TRANSMISSION_USED)
diffuse_light += light_color * diffuse_color * (vec3(1.0 / M_PI) - diffuse_brdf_NL) * transmission * attenuation;
#endif
#if defined(LIGHT_USE_RIM)
float rim_light = pow(max(0.0, 1.0 - cNdotV), max(0.0, (1.0 - roughness) * 16.0));
diffuse_light += rim_light * rim * mix(vec3(1.0), diffuse_color, rim_tint) * light_color;
#endif
}
if (roughness > 0.0) { // FIXME: roughness == 0 should not disable specular light entirely
// D
#if defined(SPECULAR_BLINN)
//normalized blinn
float shininess = exp2(15.0 * (1.0 - roughness) + 1.0) * 0.25;
float blinn = pow(cNdotH, shininess);
blinn *= (shininess + 8.0) * (1.0 / (8.0 * M_PI));
float intensity = (blinn) / max(4.0 * cNdotV * cNdotL, 0.75);
specular_light += light_color * intensity * specular_blob_intensity * attenuation;
#elif defined(SPECULAR_PHONG)
vec3 R = normalize(-reflect(L, N));
float cRdotV = max(0.0, dot(R, V));
float shininess = exp2(15.0 * (1.0 - roughness) + 1.0) * 0.25;
float phong = pow(cRdotV, shininess);
phong *= (shininess + 8.0) * (1.0 / (8.0 * M_PI));
float intensity = (phong) / max(4.0 * cNdotV * cNdotL, 0.75);
specular_light += light_color * intensity * specular_blob_intensity * attenuation;
#elif defined(SPECULAR_TOON)
vec3 R = normalize(-reflect(L, N));
float RdotV = dot(R, V);
float mid = 1.0 - roughness;
mid *= mid;
float intensity = smoothstep(mid - roughness * 0.5, mid + roughness * 0.5, RdotV) * mid;
diffuse_light += light_color * intensity * specular_blob_intensity * attenuation; // write to diffuse_light, as in toon shading you generally want no reflection
#elif defined(SPECULAR_DISABLED)
// none..
#elif defined(SPECULAR_SCHLICK_GGX)
// shlick+ggx as default
#if defined(LIGHT_ANISOTROPY_USED)
float alpha_ggx = roughness * roughness;
float aspect = sqrt(1.0 - anisotropy * 0.9);
float ax = alpha_ggx / aspect;
float ay = alpha_ggx * aspect;
float XdotH = dot(T, H);
float YdotH = dot(B, H);
float D = D_GGX_anisotropic(cNdotH, ax, ay, XdotH, YdotH);
float G = G_GGX_anisotropic_2cos(cNdotL, ax, ay, XdotH, YdotH) * G_GGX_anisotropic_2cos(cNdotV, ax, ay, XdotH, YdotH);
#else
float alpha_ggx = roughness * roughness;
float D = D_GGX(cNdotH, alpha_ggx);
float G = G_GGX_2cos(cNdotL, alpha_ggx) * G_GGX_2cos(cNdotV, alpha_ggx);
#endif
// F
vec3 f0 = F0(metallic, specular, diffuse_color);
float cLdotH5 = SchlickFresnel(cLdotH);
vec3 F = mix(vec3(cLdotH5), vec3(1.0), f0);
vec3 specular_brdf_NL = cNdotL * D * F * G;
specular_light += specular_brdf_NL * light_color * specular_blob_intensity * attenuation;
#endif
#if defined(LIGHT_USE_CLEARCOAT)
#if !defined(SPECULAR_SCHLICK_GGX)
float cLdotH5 = SchlickFresnel(cLdotH);
#endif
float Dr = GTR1(cNdotH, mix(.1, .001, clearcoat_gloss));
float Fr = mix(.04, 1.0, cLdotH5);
float Gr = G_GGX_2cos(cNdotL, .25) * G_GGX_2cos(cNdotV, .25);
float clearcoat_specular_brdf_NL = 0.25 * clearcoat * Gr * Fr * Dr * cNdotL;
specular_light += clearcoat_specular_brdf_NL * light_color * specular_blob_intensity * attenuation;
#endif
}
#ifdef USE_SHADOW_TO_OPACITY
alpha = min(alpha, clamp(1.0 - length(attenuation), 0.0, 1.0));
#endif
#endif //defined(USE_LIGHT_SHADER_CODE)
}
void main() {
//lay out everything, whathever is unused is optimized away anyway
vec3 vertex = vertex_interp;
vec3 view = -normalize(vertex_interp);
vec3 albedo = vec3(1.0);
vec3 transmission = vec3(0.0);
float metallic = 0.0;
float specular = 0.5;
vec3 emission = vec3(0.0);
float roughness = 1.0;
float rim = 0.0;
float rim_tint = 0.0;
float clearcoat = 0.0;
float clearcoat_gloss = 0.0;
float anisotropy = 0.0;
vec2 anisotropy_flow = vec2(1.0, 0.0);
#if defined(ENABLE_AO)
float ao = 1.0;
float ao_light_affect = 0.0;
#endif
float alpha = 1.0;
#if defined(ALPHA_SCISSOR_USED)
float alpha_scissor = 0.5;
#endif
#if defined(TANGENT_USED) || defined(NORMALMAP_USED) || defined(LIGHT_ANISOTROPY_USED)
vec3 binormal = normalize(binormal_interp);
vec3 tangent = normalize(tangent_interp);
#else
vec3 binormal = vec3(0.0);
vec3 tangent = vec3(0.0);
#endif
vec3 normal = normalize(normal_interp);
#if defined(DO_SIDE_CHECK)
if (!gl_FrontFacing) {
normal = -normal;
}
#endif
#if defined(UV_USED)
vec2 uv = uv_interp;
#endif
#if defined(UV2_USED) || defined(USE_LIGHTMAP)
vec2 uv2 = uv2_interp;
#endif
#if defined(COLOR_USED)
vec4 color = color_interp;
#endif
#if defined(NORMALMAP_USED)
vec3 normalmap = vec3(0.5);
#endif
float normaldepth = 1.0;
#if defined(SCREEN_UV_USED)
vec2 screen_uv = gl_FragCoord.xy * screen_pixel_size;
#endif
#if defined(SSS_USED)
float sss_strength = 0.0;
#endif
#define
{
/* clang-format off */
FRAGMENT_SHADER_CODE
/* clang-format on */
}
#if !defined(USE_SHADOW_TO_OPACITY)
#if defined(ALPHA_SCISSOR_USED)
if (alpha < alpha_scissor) {
discard;
}
#endif // ALPHA_SCISSOR_USED
#ifdef USE_OPAQUE_PREPASS
if (alpha < opaque_prepass_threshold) {
discard;
}
#endif // USE_OPAQUE_PREPASS
#endif // !USE_SHADOW_TO_OPACITY
#if defined(NORMALMAP_USED)
normalmap.xy = normalmap.xy * 2.0 - 1.0;
normalmap.z = sqrt(max(0.0, 1.0 - dot(normalmap.xy, normalmap.xy))); //always ignore Z, as it can be RG packed, Z may be pos/neg, etc.
normal = normalize(mix(normal, tangent * normalmap.x + binormal * normalmap.y + normal * normalmap.z, normaldepth));
#endif
#if defined(LIGHT_ANISOTROPY_USED)
if (anisotropy > 0.01) {
//rotation matrix
mat3 rot = mat3(tangent, binormal, normal);
//make local to space
tangent = normalize(rot * vec3(anisotropy_flow.x, anisotropy_flow.y, 0.0));
binormal = normalize(rot * vec3(-anisotropy_flow.y, anisotropy_flow.x, 0.0));
}
#endif
#ifdef ENABLE_CLIP_ALPHA
if (albedo.a < 0.99) {
//used for doublepass and shadowmapping
discard;
}
#endif
/////////////////////// LIGHTING //////////////////////////////
//apply energy conservation
vec3 specular_light = vec3(0.0, 0.0, 0.0);
vec3 diffuse_light = vec3(0.0, 0.0, 0.0);
vec3 ambient_light = vec3( 0.0, 0.0, 0.0);
//radiance
float specular_blob_intensity = 1.0;
#if defined(SPECULAR_TOON)
specular_blob_intensity *= specular * 2.0;
#endif
//gi probes
//lightmap
//lightmap capture
//process reflections
{
#if defined(DIFFUSE_TOON)
//simplify for toon, as
specular_light *= specular * metallic * albedo * 2.0;
#else
// scales the specular reflections, needs to be be computed before lighting happens,
// but after environment, GI, and reflection probes are added
// Environment brdf approximation (Lazarov 2013)
// see https://www.unrealengine.com/en-US/blog/physically-based-shading-on-mobile
const vec4 c0 = vec4(-1.0, -0.0275, -0.572, 0.022);
const vec4 c1 = vec4(1.0, 0.0425, 1.04, -0.04);
vec4 r = roughness * c0 + c1;
float ndotv = clamp(dot(normal, eye_vec), 0.0, 1.0);
float a004 = min(r.x * r.x, exp2(-9.28 * ndotv)) * r.x + r.y;
vec2 env = vec2(-1.04, 1.04) * a004 + r.zw;
vec3 f0 = F0(metallic, specular, albedo);
specular_light *= env.x * f0 + env.y;
#endif
}
//directional light
//process omni and spots
#ifdef USE_SHADOW_TO_OPACITY
alpha = min(alpha, clamp(length(ambient_light), 0.0, 1.0));
#if defined(ALPHA_SCISSOR_USED)
if (alpha < alpha_scissor) {
discard;
}
#endif // ALPHA_SCISSOR_USED
#ifdef USE_OPAQUE_PREPASS
if (alpha < opaque_prepass_threshold) {
discard;
}
#endif // USE_OPAQUE_PREPASS
#endif // USE_SHADOW_TO_OPACITY
#ifdef MODE_RENDER_DEPTH
//nothing happens, so a tree-ssa optimizer will result in no fragment shader :)
#else
specular_light *= reflection_multiplier;
ambient_light *= albedo; //ambient must be multiplied by albedo at the end
#if defined(ENABLE_AO)
ambient_light *= ao;
ao_light_affect = mix(1.0, ao, ao_light_affect);
specular_light *= ao_light_affect;
diffuse_light *= ao_light_affect;
#endif
// base color remapping
diffuse_light *= 1.0 - metallic; // TODO: avoid all diffuse and ambient light calculations when metallic == 1 up to this point
ambient_light *= 1.0 - metallic;
//fog
#ifdef MODE_MULTIPLE_RENDER_TARGETS
#ifdef USE_NO_SHADING
diffuse_buffer = vec4(albedo.rgb, 0.0);
specular_buffer = vec4(0.0);
#else
diffuse_buffer = vec4(emission + diffuse_light + ambient_light, sss_strenght);
specular_buffer = vec4(specular_light, metallic);
#endif
#else //MODE_MULTIPLE_RENDER_TARGETS
#ifdef USE_NO_SHADING
frag_color = vec4(albedo, alpha);
#else
frag_color = vec4(emission + ambient_light + diffuse_light + specular_light, alpha);
#endif //USE_NO_SHADING
#endif //MODE_MULTIPLE_RENDER_TARGETS
#endif //MODE_RENDER_DEPTH
}