/* clang-format off */
[vertex]

#define M_PI 3.14159265359

#define SHADER_IS_SRGB false

/*
from VisualServer:

ARRAY_VERTEX=0,
ARRAY_NORMAL=1,
ARRAY_TANGENT=2,
ARRAY_COLOR=3,
ARRAY_TEX_UV=4,
ARRAY_TEX_UV2=5,
ARRAY_BONES=6,
ARRAY_WEIGHTS=7,
ARRAY_INDEX=8,
*/

// hack to use uv if no uv present so it works with lightmap

/* INPUT ATTRIBS */

layout(location = 0) in highp vec4 vertex_attrib;
/* clang-format on */
layout(location = 1) in vec3 normal_attrib;
#if defined(ENABLE_TANGENT_INTERP) || defined(ENABLE_NORMALMAP) || defined(LIGHT_USE_ANISOTROPY)
layout(location = 2) in vec4 tangent_attrib;
#endif

#if defined(ENABLE_COLOR_INTERP)
layout(location = 3) in vec4 color_attrib;
#endif

#if defined(ENABLE_UV_INTERP)
layout(location = 4) in vec2 uv_attrib;
#endif

#if defined(ENABLE_UV2_INTERP) || defined(USE_LIGHTMAP)
layout(location = 5) in vec2 uv2_attrib;
#endif

#ifdef USE_SKELETON
layout(location = 6) in uvec4 bone_indices; // attrib:6
layout(location = 7) in highp vec4 bone_weights; // attrib:7
#endif

#ifdef USE_INSTANCING

layout(location = 8) in highp vec4 instance_xform0;
layout(location = 9) in highp vec4 instance_xform1;
layout(location = 10) in highp vec4 instance_xform2;
layout(location = 11) in lowp vec4 instance_color;

#if defined(ENABLE_INSTANCE_CUSTOM)
layout(location = 12) in highp vec4 instance_custom_data;
#endif

#endif

layout(std140) uniform SceneData { // ubo:0

	highp mat4 projection_matrix;
	highp mat4 inv_projection_matrix;
	highp mat4 camera_inverse_matrix;
	highp mat4 camera_matrix;

	mediump vec4 ambient_light_color;
	mediump vec4 bg_color;

	mediump vec4 fog_color_enabled;
	mediump vec4 fog_sun_color_amount;

	mediump float ambient_energy;
	mediump float bg_energy;

	mediump float z_offset;
	mediump float z_slope_scale;
	highp float shadow_dual_paraboloid_render_zfar;
	highp float shadow_dual_paraboloid_render_side;

	highp vec2 viewport_size;
	highp vec2 screen_pixel_size;
	highp vec2 shadow_atlas_pixel_size;
	highp vec2 directional_shadow_pixel_size;

	highp float time;
	highp float z_far;
	mediump float reflection_multiplier;
	mediump float subsurface_scatter_width;
	mediump float ambient_occlusion_affect_light;
	mediump float ambient_occlusion_affect_ao_channel;
	mediump float opaque_prepass_threshold;

	bool fog_depth_enabled;
	highp float fog_depth_begin;
	highp float fog_depth_end;
	mediump float fog_density;
	highp float fog_depth_curve;
	bool fog_transmit_enabled;
	highp float fog_transmit_curve;
	bool fog_height_enabled;
	highp float fog_height_min;
	highp float fog_height_max;
	highp float fog_height_curve;
};

uniform highp mat4 world_transform;

#ifdef USE_LIGHT_DIRECTIONAL

layout(std140) uniform DirectionalLightData { //ubo:3

	highp vec4 light_pos_inv_radius;
	mediump vec4 light_direction_attenuation;
	mediump vec4 light_color_energy;
	mediump vec4 light_params; // cone attenuation, angle, specular, shadow enabled,
	mediump vec4 light_clamp;
	mediump vec4 shadow_color_contact;
	highp mat4 shadow_matrix1;
	highp mat4 shadow_matrix2;
	highp mat4 shadow_matrix3;
	highp mat4 shadow_matrix4;
	mediump vec4 shadow_split_offsets;
};

#endif

#ifdef USE_VERTEX_LIGHTING
//omni and spot

struct LightData {

	highp vec4 light_pos_inv_radius;
	mediump vec4 light_direction_attenuation;
	mediump vec4 light_color_energy;
	mediump vec4 light_params; // cone attenuation, angle, specular, shadow enabled,
	mediump vec4 light_clamp;
	mediump vec4 shadow_color_contact;
	highp mat4 shadow_matrix;
};

layout(std140) uniform OmniLightData { //ubo:4

	LightData omni_lights[MAX_LIGHT_DATA_STRUCTS];
};

layout(std140) uniform SpotLightData { //ubo:5

	LightData spot_lights[MAX_LIGHT_DATA_STRUCTS];
};

#ifdef USE_FORWARD_LIGHTING

uniform int omni_light_indices[MAX_FORWARD_LIGHTS];
uniform int omni_light_count;

uniform int spot_light_indices[MAX_FORWARD_LIGHTS];
uniform int spot_light_count;

#endif

out vec4 diffuse_light_interp;
out vec4 specular_light_interp;

void light_compute(vec3 N, vec3 L, vec3 V, vec3 light_color, float roughness, inout vec3 diffuse, inout vec3 specular) {

	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_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);
	}
#else
	// lambert by default for everything else
	diffuse_brdf_NL = cNdotL * (1.0 / M_PI);
#endif

	diffuse += light_color * diffuse_brdf_NL;

	if (roughness > 0.0) {

		// D
		float specular_brdf_NL = 0.0;

#if !defined(SPECULAR_DISABLED)
		//normalized blinn always unless disabled
		vec3 H = normalize(V + L);
		float cNdotH = max(dot(N, H), 0.0);
		float shininess = exp2(15.0 * (1.0 - roughness) + 1.0) * 0.25;
		float blinn = pow(cNdotH, shininess) * cNdotL;
		blinn *= (shininess + 8.0) * (1.0 / (8.0 * M_PI));
		specular_brdf_NL = blinn;
#endif

		specular += specular_brdf_NL * light_color * (1.0 / M_PI);
	}
}

void light_process_omni(int idx, vec3 vertex, vec3 eye_vec, vec3 normal, float roughness, inout vec3 diffuse, inout vec3 specular) {

	vec3 light_rel_vec = omni_lights[idx].light_pos_inv_radius.xyz - vertex;
	float light_length = length(light_rel_vec);
	float normalized_distance = light_length * omni_lights[idx].light_pos_inv_radius.w;
	vec3 light_attenuation = vec3(pow(max(1.0 - normalized_distance, 0.0), omni_lights[idx].light_direction_attenuation.w));

	light_compute(normal, normalize(light_rel_vec), eye_vec, omni_lights[idx].light_color_energy.rgb * light_attenuation, roughness, diffuse, specular);
}

void light_process_spot(int idx, vec3 vertex, vec3 eye_vec, vec3 normal, float roughness, inout vec3 diffuse, inout vec3 specular) {

	vec3 light_rel_vec = spot_lights[idx].light_pos_inv_radius.xyz - vertex;
	float light_length = length(light_rel_vec);
	float normalized_distance = light_length * spot_lights[idx].light_pos_inv_radius.w;
	vec3 light_attenuation = vec3(pow(max(1.0 - normalized_distance, 0.001), spot_lights[idx].light_direction_attenuation.w));
	vec3 spot_dir = spot_lights[idx].light_direction_attenuation.xyz;
	float spot_cutoff = spot_lights[idx].light_params.y;
	float scos = max(dot(-normalize(light_rel_vec), spot_dir), spot_cutoff);
	float spot_rim = (1.0 - scos) / (1.0 - spot_cutoff);
	light_attenuation *= 1.0 - pow(max(spot_rim, 0.001), spot_lights[idx].light_params.x);

	light_compute(normal, normalize(light_rel_vec), eye_vec, spot_lights[idx].light_color_energy.rgb * light_attenuation, roughness, diffuse, specular);
}

#endif

/* Varyings */

out highp vec3 vertex_interp;
out vec3 normal_interp;

#if defined(ENABLE_COLOR_INTERP)
out vec4 color_interp;
#endif

#if defined(ENABLE_UV_INTERP)
out vec2 uv_interp;
#endif

#if defined(ENABLE_UV2_INTERP) || defined(USE_LIGHTMAP)
out vec2 uv2_interp;
#endif

#if defined(ENABLE_TANGENT_INTERP) || defined(ENABLE_NORMALMAP) || defined(LIGHT_USE_ANISOTROPY)
out vec3 tangent_interp;
out vec3 binormal_interp;
#endif

#if defined(USE_MATERIAL)

/* clang-format off */
layout(std140) uniform UniformData { // ubo:1

MATERIAL_UNIFORMS

};
/* clang-format on */

#endif

/* clang-format off */

VERTEX_SHADER_GLOBALS

/* clang-format on */

#ifdef RENDER_DEPTH_DUAL_PARABOLOID

out highp float dp_clip;

#endif

#define SKELETON_TEXTURE_WIDTH 256

#ifdef USE_SKELETON
uniform highp sampler2D skeleton_texture; // texunit:-1
#endif

out highp vec4 position_interp;

// 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() {

	highp vec4 vertex = vertex_attrib; // vec4(vertex_attrib.xyz * data_attrib.x,1.0);

	highp mat4 world_matrix = world_transform;

#ifdef USE_INSTANCING

	{
		highp mat4 m = mat4(instance_xform0, instance_xform1, instance_xform2, vec4(0.0, 0.0, 0.0, 1.0));
		world_matrix = world_matrix * transpose(m);
	}
#endif

	vec3 normal = normal_attrib;

#if defined(ENABLE_TANGENT_INTERP) || defined(ENABLE_NORMALMAP) || defined(LIGHT_USE_ANISOTROPY)
	vec3 tangent = tangent_attrib.xyz;
	float binormalf = tangent_attrib.a;
#endif

#if defined(ENABLE_COLOR_INTERP)
	color_interp = color_attrib;
#if defined(USE_INSTANCING)
	color_interp *= instance_color;
#endif

#endif

#if defined(ENABLE_TANGENT_INTERP) || defined(ENABLE_NORMALMAP) || defined(LIGHT_USE_ANISOTROPY)

	vec3 binormal = normalize(cross(normal, tangent) * binormalf);
#endif

#if defined(ENABLE_UV_INTERP)
	uv_interp = uv_attrib;
#endif

#if defined(ENABLE_UV2_INTERP) || defined(USE_LIGHTMAP)
	uv2_interp = uv2_attrib;
#endif

#ifdef OVERRIDE_POSITION
	highp vec4 position;
#endif

#if defined(USE_INSTANCING) && defined(ENABLE_INSTANCE_CUSTOM)
	vec4 instance_custom = instance_custom_data;
#else
	vec4 instance_custom = vec4(0.0);
#endif

	highp mat4 local_projection = projection_matrix;

//using world coordinates
#if !defined(SKIP_TRANSFORM_USED) && defined(VERTEX_WORLD_COORDS_USED)

	vertex = world_matrix * vertex;

#if defined(ENSURE_CORRECT_NORMALS)
	mat3 normal_matrix = mat3(transpose(inverse(world_matrix)));
	normal = normal_matrix * normal;
#else
	normal = normalize((world_matrix * vec4(normal, 0.0)).xyz);
#endif

#if defined(ENABLE_TANGENT_INTERP) || defined(ENABLE_NORMALMAP) || defined(LIGHT_USE_ANISOTROPY)

	tangent = normalize((world_matrix * vec4(tangent, 0.0)).xyz);
	binormal = normalize((world_matrix * vec4(binormal, 0.0)).xyz);
#endif
#endif

	float roughness = 1.0;

//defines that make writing custom shaders easier
#define projection_matrix local_projection
#define world_transform world_matrix

#ifdef USE_SKELETON
	{
		//skeleton transform
		ivec4 bone_indicesi = ivec4(bone_indices); // cast to signed int

		ivec2 tex_ofs = ivec2(bone_indicesi.x % 256, (bone_indicesi.x / 256) * 3);
		highp mat4 m;
		m = mat4(
					texelFetch(skeleton_texture, tex_ofs, 0),
					texelFetch(skeleton_texture, tex_ofs + ivec2(0, 1), 0),
					texelFetch(skeleton_texture, tex_ofs + ivec2(0, 2), 0),
					vec4(0.0, 0.0, 0.0, 1.0)) *
			bone_weights.x;

		tex_ofs = ivec2(bone_indicesi.y % 256, (bone_indicesi.y / 256) * 3);

		m += mat4(
					 texelFetch(skeleton_texture, tex_ofs, 0),
					 texelFetch(skeleton_texture, tex_ofs + ivec2(0, 1), 0),
					 texelFetch(skeleton_texture, tex_ofs + ivec2(0, 2), 0),
					 vec4(0.0, 0.0, 0.0, 1.0)) *
			 bone_weights.y;

		tex_ofs = ivec2(bone_indicesi.z % 256, (bone_indicesi.z / 256) * 3);

		m += mat4(
					 texelFetch(skeleton_texture, tex_ofs, 0),
					 texelFetch(skeleton_texture, tex_ofs + ivec2(0, 1), 0),
					 texelFetch(skeleton_texture, tex_ofs + ivec2(0, 2), 0),
					 vec4(0.0, 0.0, 0.0, 1.0)) *
			 bone_weights.z;

		tex_ofs = ivec2(bone_indicesi.w % 256, (bone_indicesi.w / 256) * 3);

		m += mat4(
					 texelFetch(skeleton_texture, tex_ofs, 0),
					 texelFetch(skeleton_texture, tex_ofs + ivec2(0, 1), 0),
					 texelFetch(skeleton_texture, tex_ofs + ivec2(0, 2), 0),
					 vec4(0.0, 0.0, 0.0, 1.0)) *
			 bone_weights.w;

		world_matrix = world_matrix * transpose(m);
	}
#endif

	highp mat4 modelview = camera_inverse_matrix * world_matrix;
	{
		/* 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 * vertex;

#if defined(ENSURE_CORRECT_NORMALS)
	mat3 normal_matrix = mat3(transpose(inverse(modelview)));
	normal = normal_matrix * normal;
#else
	normal = normalize((modelview * vec4(normal, 0.0)).xyz);
#endif

#if defined(ENABLE_TANGENT_INTERP) || defined(ENABLE_NORMALMAP) || defined(LIGHT_USE_ANISOTROPY)

	tangent = normalize((modelview * vec4(tangent, 0.0)).xyz);
	binormal = normalize((modelview * vec4(binormal, 0.0)).xyz);
#endif
#endif

//using world coordinates
#if !defined(SKIP_TRANSFORM_USED) && defined(VERTEX_WORLD_COORDS_USED)

	vertex = camera_inverse_matrix * vertex;
	normal = normalize((camera_inverse_matrix * vec4(normal, 0.0)).xyz);

#if defined(ENABLE_TANGENT_INTERP) || defined(ENABLE_NORMALMAP) || defined(LIGHT_USE_ANISOTROPY)

	tangent = normalize((camera_inverse_matrix * vec4(tangent, 0.0)).xyz);
	binormal = normalize((camera_inverse_matrix * vec4(binormal, 0.0)).xyz);
#endif
#endif

	vertex_interp = vertex.xyz;
	normal_interp = normal;

#if defined(ENABLE_TANGENT_INTERP) || defined(ENABLE_NORMALMAP) || defined(LIGHT_USE_ANISOTROPY)
	tangent_interp = tangent;
	binormal_interp = binormal;
#endif

#ifdef RENDER_DEPTH

#ifdef RENDER_DEPTH_DUAL_PARABOLOID

	vertex_interp.z *= shadow_dual_paraboloid_render_side;
	normal_interp.z *= shadow_dual_paraboloid_render_side;

	dp_clip = vertex_interp.z; //this attempts to avoid noise caused by objects sent to the other parabolloid side due to bias

	//for dual paraboloid shadow mapping, this is the fastest but least correct way, as it curves straight edges

	highp vec3 vtx = vertex_interp + normalize(vertex_interp) * z_offset;
	highp float distance = length(vtx);
	vtx = normalize(vtx);
	vtx.xy /= 1.0 - vtx.z;
	vtx.z = (distance / shadow_dual_paraboloid_render_zfar);
	vtx.z = vtx.z * 2.0 - 1.0;

	vertex_interp = vtx;

#else

	float z_ofs = z_offset;
	z_ofs += (1.0 - abs(normal_interp.z)) * z_slope_scale;
	vertex_interp.z -= z_ofs;

#endif //RENDER_DEPTH_DUAL_PARABOLOID

#endif //RENDER_DEPTH

#ifdef OVERRIDE_POSITION
	gl_Position = position;
#else
	gl_Position = projection_matrix * vec4(vertex_interp, 1.0);
#endif

	position_interp = gl_Position;

#ifdef USE_VERTEX_LIGHTING

	diffuse_light_interp = vec4(0.0);
	specular_light_interp = vec4(0.0);

#ifdef USE_FORWARD_LIGHTING

	for (int i = 0; i < omni_light_count; i++) {
		light_process_omni(omni_light_indices[i], vertex_interp, -normalize(vertex_interp), normal_interp, roughness, diffuse_light_interp.rgb, specular_light_interp.rgb);
	}

	for (int i = 0; i < spot_light_count; i++) {
		light_process_spot(spot_light_indices[i], vertex_interp, -normalize(vertex_interp), normal_interp, roughness, diffuse_light_interp.rgb, specular_light_interp.rgb);
	}
#endif

#ifdef USE_LIGHT_DIRECTIONAL

	vec3 directional_diffuse = vec3(0.0);
	vec3 directional_specular = vec3(0.0);
	light_compute(normal_interp, -light_direction_attenuation.xyz, -normalize(vertex_interp), light_color_energy.rgb, roughness, directional_diffuse, directional_specular);

	float diff_avg = dot(diffuse_light_interp.rgb, vec3(0.33333));
	float diff_dir_avg = dot(directional_diffuse, vec3(0.33333));
	if (diff_avg > 0.0) {
		diffuse_light_interp.a = diff_dir_avg / (diff_avg + diff_dir_avg);
	} else {
		diffuse_light_interp.a = 1.0;
	}

	diffuse_light_interp.rgb += directional_diffuse;

	float spec_avg = dot(specular_light_interp.rgb, vec3(0.33333));
	float spec_dir_avg = dot(directional_specular, vec3(0.33333));
	if (spec_avg > 0.0) {
		specular_light_interp.a = spec_dir_avg / (spec_avg + spec_dir_avg);
	} else {
		specular_light_interp.a = 1.0;
	}

	specular_light_interp.rgb += directional_specular;

#endif //USE_LIGHT_DIRECTIONAL

#endif // USE_VERTEX_LIGHTING
}

/* clang-format off */
[fragment]


/* texture unit usage, N is max_texture_unity-N

1-skeleton
2-radiance
3-reflection_atlas
4-directional_shadow
5-shadow_atlas
6-decal_atlas
7-screen
8-depth
9-probe1
10-probe2

*/

uniform highp mat4 world_transform;
/* clang-format on */

#define M_PI 3.14159265359
#define SHADER_IS_SRGB false

/* Varyings */

#if defined(ENABLE_COLOR_INTERP)
in vec4 color_interp;
#endif

#if defined(ENABLE_UV_INTERP)
in vec2 uv_interp;
#endif

#if defined(ENABLE_UV2_INTERP) || defined(USE_LIGHTMAP)
in vec2 uv2_interp;
#endif

#if defined(ENABLE_TANGENT_INTERP) || defined(ENABLE_NORMALMAP) || defined(LIGHT_USE_ANISOTROPY)
in vec3 tangent_interp;
in vec3 binormal_interp;
#endif

in highp vec3 vertex_interp;
in vec3 normal_interp;

/* PBR CHANNELS */

#ifdef USE_RADIANCE_MAP

layout(std140) uniform Radiance { // ubo:2

	mat4 radiance_inverse_xform;
	float radiance_ambient_contribution;
};

#define RADIANCE_MAX_LOD 5.0

uniform sampler2D irradiance_map; // texunit:-6

#ifdef USE_RADIANCE_MAP_ARRAY

uniform sampler2DArray radiance_map; // texunit:-2

vec3 textureDualParaboloid(sampler2DArray p_tex, vec3 p_vec, float p_roughness) {

	vec3 norm = normalize(p_vec);
	norm.xy /= 1.0 + abs(norm.z);
	norm.xy = norm.xy * vec2(0.5, 0.25) + vec2(0.5, 0.25);

	// we need to lie the derivatives (normg) and assume that DP side is always the same
	// to get proper texture filtering
	vec2 normg = norm.xy;
	if (norm.z > 0.0) {
		norm.y = 0.5 - norm.y + 0.5;
	}

	// thanks to OpenGL spec using floor(layer + 0.5) for texture arrays,
	// it's easy to have precision errors using fract() to interpolate layers
	// as such, using fixed point to ensure it works.

	float index = p_roughness * RADIANCE_MAX_LOD;
	int indexi = int(index * 256.0);
	vec3 base = textureGrad(p_tex, vec3(norm.xy, float(indexi / 256)), dFdx(normg), dFdy(normg)).xyz;
	vec3 next = textureGrad(p_tex, vec3(norm.xy, float(indexi / 256 + 1)), dFdx(normg), dFdy(normg)).xyz;
	return mix(base, next, float(indexi % 256) / 256.0);
}

#else

uniform sampler2D radiance_map; // texunit:-2

vec3 textureDualParaboloid(sampler2D p_tex, vec3 p_vec, float p_roughness) {

	vec3 norm = normalize(p_vec);
	norm.xy /= 1.0 + abs(norm.z);
	norm.xy = norm.xy * vec2(0.5, 0.25) + vec2(0.5, 0.25);
	if (norm.z > 0.0) {
		norm.y = 0.5 - norm.y + 0.5;
	}
	return textureLod(p_tex, norm.xy, p_roughness * RADIANCE_MAX_LOD).xyz;
}

#endif

#endif

/* Material Uniforms */

#if defined(USE_MATERIAL)

/* clang-format off */
layout(std140) uniform UniformData {

MATERIAL_UNIFORMS

};
/* clang-format on */

#endif

/* clang-format off */

FRAGMENT_SHADER_GLOBALS

/* clang-format on */

layout(std140) uniform SceneData {

	highp mat4 projection_matrix;
	highp mat4 inv_projection_matrix;
	highp mat4 camera_inverse_matrix;
	highp mat4 camera_matrix;

	mediump vec4 ambient_light_color;
	mediump vec4 bg_color;

	mediump vec4 fog_color_enabled;
	mediump vec4 fog_sun_color_amount;

	mediump float ambient_energy;
	mediump float bg_energy;

	mediump float z_offset;
	mediump float z_slope_scale;
	highp float shadow_dual_paraboloid_render_zfar;
	highp float shadow_dual_paraboloid_render_side;

	highp vec2 viewport_size;
	highp vec2 screen_pixel_size;
	highp vec2 shadow_atlas_pixel_size;
	highp vec2 directional_shadow_pixel_size;

	highp float time;
	highp float z_far;
	mediump float reflection_multiplier;
	mediump float subsurface_scatter_width;
	mediump float ambient_occlusion_affect_light;
	mediump float ambient_occlusion_affect_ao_channel;
	mediump float opaque_prepass_threshold;

	bool fog_depth_enabled;
	highp float fog_depth_begin;
	highp float fog_depth_end;
	mediump float fog_density;
	highp float fog_depth_curve;
	bool fog_transmit_enabled;
	highp float fog_transmit_curve;
	bool fog_height_enabled;
	highp float fog_height_min;
	highp float fog_height_max;
	highp float fog_height_curve;
};

	//directional light data

#ifdef USE_LIGHT_DIRECTIONAL

layout(std140) uniform DirectionalLightData {

	highp vec4 light_pos_inv_radius;
	mediump vec4 light_direction_attenuation;
	mediump vec4 light_color_energy;
	mediump vec4 light_params; // cone attenuation, angle, specular, shadow enabled,
	mediump vec4 light_clamp;
	mediump vec4 shadow_color_contact;
	highp mat4 shadow_matrix1;
	highp mat4 shadow_matrix2;
	highp mat4 shadow_matrix3;
	highp mat4 shadow_matrix4;
	mediump vec4 shadow_split_offsets;
};

uniform highp sampler2DShadow directional_shadow; // texunit:-4

#endif

#ifdef USE_VERTEX_LIGHTING
in vec4 diffuse_light_interp;
in vec4 specular_light_interp;
#endif
// omni and spot

struct LightData {

	highp vec4 light_pos_inv_radius;
	mediump vec4 light_direction_attenuation;
	mediump vec4 light_color_energy;
	mediump vec4 light_params; // cone attenuation, angle, specular, shadow enabled,
	mediump vec4 light_clamp;
	mediump vec4 shadow_color_contact;
	highp mat4 shadow_matrix;
};

layout(std140) uniform OmniLightData { // ubo:4

	LightData omni_lights[MAX_LIGHT_DATA_STRUCTS];
};

layout(std140) uniform SpotLightData { // ubo:5

	LightData spot_lights[MAX_LIGHT_DATA_STRUCTS];
};

uniform highp sampler2DShadow shadow_atlas; // texunit:-5

struct ReflectionData {

	mediump vec4 box_extents;
	mediump vec4 box_offset;
	mediump vec4 params; // intensity, 0, interior , boxproject
	mediump vec4 ambient; // ambient color, energy
	mediump vec4 atlas_clamp;
	highp mat4 local_matrix; // up to here for spot and omni, rest is for directional
	// notes: for ambientblend, use distance to edge to blend between already existing global environment
};

layout(std140) uniform ReflectionProbeData { //ubo:6

	ReflectionData reflections[MAX_REFLECTION_DATA_STRUCTS];
};
uniform mediump sampler2D reflection_atlas; // texunit:-3

#ifdef USE_FORWARD_LIGHTING

uniform int omni_light_indices[MAX_FORWARD_LIGHTS];
uniform int omni_light_count;

uniform int spot_light_indices[MAX_FORWARD_LIGHTS];
uniform int spot_light_count;

uniform int reflection_indices[MAX_FORWARD_LIGHTS];
uniform int reflection_count;

#endif

#if defined(SCREEN_TEXTURE_USED)

uniform highp sampler2D screen_texture; // texunit:-7

#endif

#ifdef USE_MULTIPLE_RENDER_TARGETS

layout(location = 0) out vec4 diffuse_buffer;
layout(location = 1) out vec4 specular_buffer;
layout(location = 2) out vec4 normal_mr_buffer;
#if defined(ENABLE_SSS)
layout(location = 3) out float sss_buffer;
#endif

#else

layout(location = 0) out vec4 frag_color;

#endif

in highp vec4 position_interp;
uniform highp sampler2D depth_buffer; // texunit:-8

#ifdef USE_CONTACT_SHADOWS

float contact_shadow_compute(vec3 pos, vec3 dir, float max_distance) {

	if (abs(dir.z) > 0.99)
		return 1.0;

	vec3 endpoint = pos + dir * max_distance;
	vec4 source = position_interp;
	vec4 dest = projection_matrix * vec4(endpoint, 1.0);

	vec2 from_screen = (source.xy / source.w) * 0.5 + 0.5;
	vec2 to_screen = (dest.xy / dest.w) * 0.5 + 0.5;

	vec2 screen_rel = to_screen - from_screen;

	if (length(screen_rel) < 0.00001)
		return 1.0; // too small, don't do anything

	/*
	float pixel_size; // approximate pixel size

	if (screen_rel.x > screen_rel.y) {

		pixel_size = abs((pos.x - endpoint.x) / (screen_rel.x / screen_pixel_size.x));
	} else {
		pixel_size = abs((pos.y - endpoint.y) / (screen_rel.y / screen_pixel_size.y));
	}
	*/
	vec4 bias = projection_matrix * vec4(pos + vec3(0.0, 0.0, max_distance * 0.5), 1.0);

	vec2 pixel_incr = normalize(screen_rel) * screen_pixel_size;

	float steps = length(screen_rel) / length(pixel_incr);
	steps = min(2000.0, steps); // put a limit to avoid freezing in some strange situation
	//steps = 10.0;

	vec4 incr = (dest - source) / steps;
	float ratio = 0.0;
	float ratio_incr = 1.0 / steps;

	while (steps > 0.0) {
		source += incr * 2.0;
		bias += incr * 2.0;

		vec3 uv_depth = (source.xyz / source.w) * 0.5 + 0.5;
		float depth = texture(depth_buffer, uv_depth.xy).r;

		if (depth < uv_depth.z) {
			if (depth > (bias.z / bias.w) * 0.5 + 0.5) {
				return min(pow(ratio, 4.0), 1.0);
			} else {
				return 1.0;
			}
		}

		ratio += ratio_incr;
		steps -= 1.0;
	}

	return 1.0;
}

#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) * cNdotL;
		blinn *= (shininess + 8.0) * (1.0 / (8.0 * M_PI));
		float intensity = blinn;

		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_USE_ANISOTROPY)

		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)
}

float sample_shadow(highp sampler2DShadow shadow, vec2 shadow_pixel_size, vec2 pos, float depth, vec4 clamp_rect) {

#ifdef SHADOW_MODE_PCF_13

	float avg = textureProj(shadow, vec4(pos, depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(shadow_pixel_size.x, 0.0), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(-shadow_pixel_size.x, 0.0), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(0.0, shadow_pixel_size.y), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(0.0, -shadow_pixel_size.y), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(shadow_pixel_size.x, shadow_pixel_size.y), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(-shadow_pixel_size.x, shadow_pixel_size.y), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(shadow_pixel_size.x, -shadow_pixel_size.y), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(-shadow_pixel_size.x, -shadow_pixel_size.y), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(shadow_pixel_size.x * 2.0, 0.0), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(-shadow_pixel_size.x * 2.0, 0.0), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(0.0, shadow_pixel_size.y * 2.0), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(0.0, -shadow_pixel_size.y * 2.0), depth, 1.0));
	return avg * (1.0 / 13.0);
#endif

#ifdef SHADOW_MODE_PCF_5

	float avg = textureProj(shadow, vec4(pos, depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(shadow_pixel_size.x, 0.0), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(-shadow_pixel_size.x, 0.0), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(0.0, shadow_pixel_size.y), depth, 1.0));
	avg += textureProj(shadow, vec4(pos + vec2(0.0, -shadow_pixel_size.y), depth, 1.0));
	return avg * (1.0 / 5.0);

#endif

#if !defined(SHADOW_MODE_PCF_5) || !defined(SHADOW_MODE_PCF_13)

	return textureProj(shadow, vec4(pos, depth, 1.0));

#endif
}

#ifdef RENDER_DEPTH_DUAL_PARABOLOID

in highp float dp_clip;

#endif

#if 0
// need to save texture depth for this
vec3 light_transmittance(float translucency,vec3 light_vec, vec3 normal, vec3 pos, float distance) {

	float scale = 8.25 * (1.0 - translucency) / subsurface_scatter_width;
	float d = scale * distance;

	/**
	* Armed with the thickness, we can now calculate the color by means of the
	* precalculated transmittance profile.
	* (It can be precomputed into a texture, for maximum performance):
	*/
	float dd = -d * d;
	vec3 profile =
			vec3(0.233, 0.455, 0.649) * exp(dd / 0.0064) +
			vec3(0.1,   0.336, 0.344) * exp(dd / 0.0484) +
			vec3(0.118, 0.198, 0.0)   * exp(dd / 0.187)  +
			vec3(0.113, 0.007, 0.007) * exp(dd / 0.567)  +
			vec3(0.358, 0.004, 0.0)   * exp(dd / 1.99)   +
			vec3(0.078, 0.0,   0.0)   * exp(dd / 7.41);

	/**
	* Using the profile, we finally approximate the transmitted lighting from
	* the back of the object:
	*/
	return profile * clamp(0.3 + dot(light_vec, normal),0.0,1.0);
}
#endif

void light_process_omni(int idx, vec3 vertex, vec3 eye_vec, vec3 normal, vec3 binormal, vec3 tangent, vec3 albedo, vec3 transmission, float roughness, float metallic, float specular, float rim, float rim_tint, float clearcoat, float clearcoat_gloss, float anisotropy, float p_blob_intensity, inout vec3 diffuse_light, inout vec3 specular_light, inout float alpha) {

	vec3 light_rel_vec = omni_lights[idx].light_pos_inv_radius.xyz - vertex;
	float light_length = length(light_rel_vec);
	float normalized_distance = light_length * omni_lights[idx].light_pos_inv_radius.w;
	float omni_attenuation = pow(max(1.0 - normalized_distance, 0.0), omni_lights[idx].light_direction_attenuation.w);
	vec3 light_attenuation = vec3(omni_attenuation);

#if !defined(SHADOWS_DISABLED)
#ifdef USE_SHADOW
	if (omni_lights[idx].light_params.w > 0.5) {
		// there is a shadowmap

		highp vec3 splane = (omni_lights[idx].shadow_matrix * vec4(vertex, 1.0)).xyz;
		float shadow_len = length(splane);
		splane = normalize(splane);
		vec4 clamp_rect = omni_lights[idx].light_clamp;

		if (splane.z >= 0.0) {

			splane.z += 1.0;

			clamp_rect.y += clamp_rect.w;

		} else {

			splane.z = 1.0 - splane.z;

			/*
			if (clamp_rect.z < clamp_rect.w) {
				clamp_rect.x += clamp_rect.z;
			} else {
				clamp_rect.y += clamp_rect.w;
			}
			*/
		}

		splane.xy /= splane.z;
		splane.xy = splane.xy * 0.5 + 0.5;
		splane.z = shadow_len * omni_lights[idx].light_pos_inv_radius.w;

		splane.xy = clamp_rect.xy + splane.xy * clamp_rect.zw;
		float shadow = sample_shadow(shadow_atlas, shadow_atlas_pixel_size, splane.xy, splane.z, clamp_rect);

#ifdef USE_CONTACT_SHADOWS

		if (shadow > 0.01 && omni_lights[idx].shadow_color_contact.a > 0.0) {

			float contact_shadow = contact_shadow_compute(vertex, normalize(light_rel_vec), min(light_length, omni_lights[idx].shadow_color_contact.a));
			shadow = min(shadow, contact_shadow);
		}
#endif
		light_attenuation *= mix(omni_lights[idx].shadow_color_contact.rgb, vec3(1.0), shadow);
	}
#endif //USE_SHADOW
#endif //SHADOWS_DISABLED
	light_compute(normal, normalize(light_rel_vec), eye_vec, binormal, tangent, omni_lights[idx].light_color_energy.rgb, light_attenuation, albedo, transmission, omni_lights[idx].light_params.z * p_blob_intensity, roughness, metallic, specular, rim * omni_attenuation, rim_tint, clearcoat, clearcoat_gloss, anisotropy, diffuse_light, specular_light, alpha);
}

void light_process_spot(int idx, vec3 vertex, vec3 eye_vec, vec3 normal, vec3 binormal, vec3 tangent, vec3 albedo, vec3 transmission, float roughness, float metallic, float specular, float rim, float rim_tint, float clearcoat, float clearcoat_gloss, float anisotropy, float p_blob_intensity, inout vec3 diffuse_light, inout vec3 specular_light, inout float alpha) {

	vec3 light_rel_vec = spot_lights[idx].light_pos_inv_radius.xyz - vertex;
	float light_length = length(light_rel_vec);
	float normalized_distance = light_length * spot_lights[idx].light_pos_inv_radius.w;
	float spot_attenuation = pow(max(1.0 - normalized_distance, 0.001), spot_lights[idx].light_direction_attenuation.w);
	vec3 spot_dir = spot_lights[idx].light_direction_attenuation.xyz;
	float spot_cutoff = spot_lights[idx].light_params.y;
	float scos = max(dot(-normalize(light_rel_vec), spot_dir), spot_cutoff);
	float spot_rim = max(0.0001, (1.0 - scos) / (1.0 - spot_cutoff));
	spot_attenuation *= 1.0 - pow(spot_rim, spot_lights[idx].light_params.x);
	vec3 light_attenuation = vec3(spot_attenuation);

#if !defined(SHADOWS_DISABLED)
#ifdef USE_SHADOW
	if (spot_lights[idx].light_params.w > 0.5) {
		//there is a shadowmap
		highp vec4 splane = (spot_lights[idx].shadow_matrix * vec4(vertex, 1.0));
		splane.xyz /= splane.w;

		float shadow = sample_shadow(shadow_atlas, shadow_atlas_pixel_size, splane.xy, splane.z, spot_lights[idx].light_clamp);

#ifdef USE_CONTACT_SHADOWS
		if (shadow > 0.01 && spot_lights[idx].shadow_color_contact.a > 0.0) {

			float contact_shadow = contact_shadow_compute(vertex, normalize(light_rel_vec), min(light_length, spot_lights[idx].shadow_color_contact.a));
			shadow = min(shadow, contact_shadow);
		}
#endif
		light_attenuation *= mix(spot_lights[idx].shadow_color_contact.rgb, vec3(1.0), shadow);
	}
#endif //USE_SHADOW
#endif //SHADOWS_DISABLED

	light_compute(normal, normalize(light_rel_vec), eye_vec, binormal, tangent, spot_lights[idx].light_color_energy.rgb, light_attenuation, albedo, transmission, spot_lights[idx].light_params.z * p_blob_intensity, roughness, metallic, specular, rim * spot_attenuation, rim_tint, clearcoat, clearcoat_gloss, anisotropy, diffuse_light, specular_light, alpha);
}

void reflection_process(int idx, vec3 vertex, vec3 normal, vec3 binormal, vec3 tangent, float roughness, float anisotropy, vec3 ambient, vec3 skybox, inout highp vec4 reflection_accum, inout highp vec4 ambient_accum) {

	vec3 ref_vec = normalize(reflect(vertex, normal));
	vec3 local_pos = (reflections[idx].local_matrix * vec4(vertex, 1.0)).xyz;
	vec3 box_extents = reflections[idx].box_extents.xyz;

	if (any(greaterThan(abs(local_pos), box_extents))) { //out of the reflection box
		return;
	}

	vec3 inner_pos = abs(local_pos / box_extents);
	float blend = max(inner_pos.x, max(inner_pos.y, inner_pos.z));
	//make blend more rounded
	blend = mix(length(inner_pos), blend, blend);
	blend *= blend;
	blend = max(0.0, 1.0 - blend);

	if (reflections[idx].params.x > 0.0) { // compute reflection

		vec3 local_ref_vec = (reflections[idx].local_matrix * vec4(ref_vec, 0.0)).xyz;

		if (reflections[idx].params.w > 0.5) { //box project

			vec3 nrdir = normalize(local_ref_vec);
			vec3 rbmax = (box_extents - local_pos) / nrdir;
			vec3 rbmin = (-box_extents - local_pos) / nrdir;

			vec3 rbminmax = mix(rbmin, rbmax, greaterThan(nrdir, vec3(0.0, 0.0, 0.0)));

			float fa = min(min(rbminmax.x, rbminmax.y), rbminmax.z);
			vec3 posonbox = local_pos + nrdir * fa;
			local_ref_vec = posonbox - reflections[idx].box_offset.xyz;
		}

		vec4 clamp_rect = reflections[idx].atlas_clamp;
		vec3 norm = normalize(local_ref_vec);
		norm.xy /= 1.0 + abs(norm.z);
		norm.xy = norm.xy * vec2(0.5, 0.25) + vec2(0.5, 0.25);
		if (norm.z > 0.0) {
			norm.y = 0.5 - norm.y + 0.5;
		}

		vec2 atlas_uv = norm.xy * clamp_rect.zw + clamp_rect.xy;
		atlas_uv = clamp(atlas_uv, clamp_rect.xy, clamp_rect.xy + clamp_rect.zw);

		highp vec4 reflection;
		reflection.rgb = textureLod(reflection_atlas, atlas_uv, roughness * 5.0).rgb;

		if (reflections[idx].params.z < 0.5) {
			reflection.rgb = mix(skybox, reflection.rgb, blend);
		}
		reflection.rgb *= reflections[idx].params.x;
		reflection.a = blend;
		reflection.rgb *= reflection.a;

		reflection_accum += reflection;
	}
#if !defined(USE_LIGHTMAP) && !defined(USE_LIGHTMAP_CAPTURE)
	if (reflections[idx].ambient.a > 0.0) { //compute ambient using skybox

		vec3 local_amb_vec = (reflections[idx].local_matrix * vec4(normal, 0.0)).xyz;

		vec3 splane = normalize(local_amb_vec);
		vec4 clamp_rect = reflections[idx].atlas_clamp;

		splane.z *= -1.0;
		if (splane.z >= 0.0) {
			splane.z += 1.0;
			clamp_rect.y += clamp_rect.w;
		} else {
			splane.z = 1.0 - splane.z;
			splane.y = -splane.y;
		}

		splane.xy /= splane.z;
		splane.xy = splane.xy * 0.5 + 0.5;

		splane.xy = splane.xy * clamp_rect.zw + clamp_rect.xy;
		splane.xy = clamp(splane.xy, clamp_rect.xy, clamp_rect.xy + clamp_rect.zw);

		highp vec4 ambient_out;
		ambient_out.a = blend;
		ambient_out.rgb = textureLod(reflection_atlas, splane.xy, 5.0).rgb;
		ambient_out.rgb = mix(reflections[idx].ambient.rgb, ambient_out.rgb, reflections[idx].ambient.a);
		if (reflections[idx].params.z < 0.5) {
			ambient_out.rgb = mix(ambient, ambient_out.rgb, blend);
		}

		ambient_out.rgb *= ambient_out.a;
		ambient_accum += ambient_out;
	} else {

		highp vec4 ambient_out;
		ambient_out.a = blend;
		ambient_out.rgb = reflections[idx].ambient.rgb;
		if (reflections[idx].params.z < 0.5) {
			ambient_out.rgb = mix(ambient, ambient_out.rgb, blend);
		}
		ambient_out.rgb *= ambient_out.a;
		ambient_accum += ambient_out;
	}
#endif
}

#ifdef USE_LIGHTMAP
uniform mediump sampler2D lightmap; //texunit:-9
uniform mediump float lightmap_energy;
#endif

#ifdef USE_LIGHTMAP_CAPTURE
uniform mediump vec4[12] lightmap_captures;
uniform bool lightmap_capture_sky;

#endif

#ifdef USE_GI_PROBES

uniform mediump sampler3D gi_probe1; //texunit:-9
uniform highp mat4 gi_probe_xform1;
uniform highp vec3 gi_probe_bounds1;
uniform highp vec3 gi_probe_cell_size1;
uniform highp float gi_probe_multiplier1;
uniform highp float gi_probe_bias1;
uniform highp float gi_probe_normal_bias1;
uniform bool gi_probe_blend_ambient1;

uniform mediump sampler3D gi_probe2; //texunit:-10
uniform highp mat4 gi_probe_xform2;
uniform highp vec3 gi_probe_bounds2;
uniform highp vec3 gi_probe_cell_size2;
uniform highp float gi_probe_multiplier2;
uniform highp float gi_probe_bias2;
uniform highp float gi_probe_normal_bias2;
uniform bool gi_probe2_enabled;
uniform bool gi_probe_blend_ambient2;

vec3 voxel_cone_trace(mediump sampler3D probe, vec3 cell_size, vec3 pos, vec3 ambient, bool blend_ambient, vec3 direction, float tan_half_angle, float max_distance, float p_bias) {

	float dist = p_bias; //1.0; //dot(direction,mix(vec3(-1.0),vec3(1.0),greaterThan(direction,vec3(0.0))))*2.0;
	float alpha = 0.0;
	vec3 color = vec3(0.0);

	while (dist < max_distance && alpha < 0.95) {
		float diameter = max(1.0, 2.0 * tan_half_angle * dist);
		vec4 scolor = textureLod(probe, (pos + dist * direction) * cell_size, log2(diameter));
		float a = (1.0 - alpha);
		color += scolor.rgb * a;
		alpha += a * scolor.a;
		dist += diameter * 0.5;
	}

	if (blend_ambient) {
		color.rgb = mix(ambient, color.rgb, min(1.0, alpha / 0.95));
	}

	return color;
}

void gi_probe_compute(mediump sampler3D probe, mat4 probe_xform, vec3 bounds, vec3 cell_size, vec3 pos, vec3 ambient, vec3 environment, bool blend_ambient, float multiplier, mat3 normal_mtx, vec3 ref_vec, float roughness, float p_bias, float p_normal_bias, inout vec4 out_spec, inout vec4 out_diff) {

	vec3 probe_pos = (probe_xform * vec4(pos, 1.0)).xyz;
	vec3 ref_pos = (probe_xform * vec4(pos + ref_vec, 1.0)).xyz;
	ref_vec = normalize(ref_pos - probe_pos);

	probe_pos += (probe_xform * vec4(normal_mtx[2], 0.0)).xyz * p_normal_bias;

	/*	out_diff.rgb = voxel_cone_trace(probe,cell_size,probe_pos,normalize((probe_xform * vec4(ref_vec,0.0)).xyz),0.0 ,100.0);
	out_diff.a = 1.0;
	return;*/
	//out_diff = vec4(textureLod(probe,probe_pos*cell_size,3.0).rgb,1.0);
	//return;

	//this causes corrupted pixels, i have no idea why..
	if (any(bvec2(any(lessThan(probe_pos, vec3(0.0))), any(greaterThan(probe_pos, bounds))))) {
		return;
	}

	vec3 blendv = abs(probe_pos / bounds * 2.0 - 1.0);
	float blend = clamp(1.0 - max(blendv.x, max(blendv.y, blendv.z)), 0.0, 1.0);
	//float blend=1.0;

	float max_distance = length(bounds);

	//radiance
#ifdef VCT_QUALITY_HIGH

#define MAX_CONE_DIRS 6
	vec3 cone_dirs[MAX_CONE_DIRS] = vec3[](
			vec3(0.0, 0.0, 1.0),
			vec3(0.866025, 0.0, 0.5),
			vec3(0.267617, 0.823639, 0.5),
			vec3(-0.700629, 0.509037, 0.5),
			vec3(-0.700629, -0.509037, 0.5),
			vec3(0.267617, -0.823639, 0.5));

	float cone_weights[MAX_CONE_DIRS] = float[](0.25, 0.15, 0.15, 0.15, 0.15, 0.15);
	float cone_angle_tan = 0.577;
	float min_ref_tan = 0.0;
#else

#define MAX_CONE_DIRS 4

	vec3 cone_dirs[MAX_CONE_DIRS] = vec3[](
			vec3(0.707107, 0.0, 0.707107),
			vec3(0.0, 0.707107, 0.707107),
			vec3(-0.707107, 0.0, 0.707107),
			vec3(0.0, -0.707107, 0.707107));

	float cone_weights[MAX_CONE_DIRS] = float[](0.25, 0.25, 0.25, 0.25);
	float cone_angle_tan = 0.98269;
	max_distance *= 0.5;
	float min_ref_tan = 0.2;

#endif
	vec3 light = vec3(0.0);
	for (int i = 0; i < MAX_CONE_DIRS; i++) {

		vec3 dir = normalize((probe_xform * vec4(pos + normal_mtx * cone_dirs[i], 1.0)).xyz - probe_pos);
		light += cone_weights[i] * voxel_cone_trace(probe, cell_size, probe_pos, ambient, blend_ambient, dir, cone_angle_tan, max_distance, p_bias);
	}

	light *= multiplier;

	out_diff += vec4(light * blend, blend);

	//irradiance

	vec3 irr_light = voxel_cone_trace(probe, cell_size, probe_pos, environment, blend_ambient, ref_vec, max(min_ref_tan, tan(roughness * 0.5 * M_PI * 0.99)), max_distance, p_bias);

	irr_light *= multiplier;
	//irr_light=vec3(0.0);

	out_spec += vec4(irr_light * blend, blend);
}

void gi_probes_compute(vec3 pos, vec3 normal, float roughness, inout vec3 out_specular, inout vec3 out_ambient) {

	roughness = roughness * roughness;

	vec3 ref_vec = normalize(reflect(normalize(pos), normal));

	//find arbitrary tangent and bitangent, then build a matrix
	vec3 v0 = abs(normal.z) < 0.999 ? vec3(0.0, 0.0, 1.0) : vec3(0.0, 1.0, 0.0);
	vec3 tangent = normalize(cross(v0, normal));
	vec3 bitangent = normalize(cross(tangent, normal));
	mat3 normal_mat = mat3(tangent, bitangent, normal);

	vec4 diff_accum = vec4(0.0);
	vec4 spec_accum = vec4(0.0);

	vec3 ambient = out_ambient;
	out_ambient = vec3(0.0);

	vec3 environment = out_specular;

	out_specular = vec3(0.0);

	gi_probe_compute(gi_probe1, gi_probe_xform1, gi_probe_bounds1, gi_probe_cell_size1, pos, ambient, environment, gi_probe_blend_ambient1, gi_probe_multiplier1, normal_mat, ref_vec, roughness, gi_probe_bias1, gi_probe_normal_bias1, spec_accum, diff_accum);

	if (gi_probe2_enabled) {

		gi_probe_compute(gi_probe2, gi_probe_xform2, gi_probe_bounds2, gi_probe_cell_size2, pos, ambient, environment, gi_probe_blend_ambient2, gi_probe_multiplier2, normal_mat, ref_vec, roughness, gi_probe_bias2, gi_probe_normal_bias2, spec_accum, diff_accum);
	}

	if (diff_accum.a > 0.0) {
		diff_accum.rgb /= diff_accum.a;
	}

	if (spec_accum.a > 0.0) {
		spec_accum.rgb /= spec_accum.a;
	}

	out_specular += spec_accum.rgb;
	out_ambient += diff_accum.rgb;
}

#endif

void main() {

#ifdef RENDER_DEPTH_DUAL_PARABOLOID

	if (dp_clip > 0.0)
		discard;
#endif

	//lay out everything, whathever is unused is optimized away anyway
	highp 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(ENABLE_TANGENT_INTERP) || defined(ENABLE_NORMALMAP) || defined(LIGHT_USE_ANISOTROPY)
	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(ENABLE_UV_INTERP)
	vec2 uv = uv_interp;
#endif

#if defined(ENABLE_UV2_INTERP) || defined(USE_LIGHTMAP)
	vec2 uv2 = uv2_interp;
#endif

#if defined(ENABLE_COLOR_INTERP)
	vec4 color = color_interp;
#endif

#if defined(ENABLE_NORMALMAP)

	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(ENABLE_SSS)
	float sss_strength = 0.0;
#endif

	{
		/* 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(ENABLE_NORMALMAP)

	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_USE_ANISOTROPY)

	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

#ifdef USE_VERTEX_LIGHTING

	vec3 specular_light = specular_light_interp.rgb;
	vec3 diffuse_light = diffuse_light_interp.rgb;
#else

	vec3 specular_light = vec3(0.0, 0.0, 0.0);
	vec3 diffuse_light = vec3(0.0, 0.0, 0.0);

#endif

	vec3 ambient_light;
	vec3 env_reflection_light = vec3(0.0, 0.0, 0.0);

	vec3 eye_vec = view;

	// IBL precalculations
	float ndotv = clamp(dot(normal, eye_vec), 0.0, 1.0);
	vec3 f0 = F0(metallic, specular, albedo);
	vec3 F = f0 + (max(vec3(1.0 - roughness), f0) - f0) * pow(1.0 - ndotv, 5.0);

#ifdef USE_RADIANCE_MAP

#ifdef AMBIENT_LIGHT_DISABLED
	ambient_light = vec3(0.0, 0.0, 0.0);
#else
	{

		{ //read radiance from dual paraboloid

			vec3 ref_vec = reflect(-eye_vec, normal);
			ref_vec = normalize((radiance_inverse_xform * vec4(ref_vec, 0.0)).xyz);
			vec3 radiance = textureDualParaboloid(radiance_map, ref_vec, roughness) * bg_energy;
			env_reflection_light = radiance;
		}
	}
#ifndef USE_LIGHTMAP
	{

		vec3 norm = normal;
		norm = normalize((radiance_inverse_xform * vec4(norm, 0.0)).xyz);
		norm.xy /= 1.0 + abs(norm.z);
		norm.xy = norm.xy * vec2(0.5, 0.25) + vec2(0.5, 0.25);
		if (norm.z > 0.0) {
			norm.y = 0.5 - norm.y + 0.5;
		}

		vec3 env_ambient = texture(irradiance_map, norm.xy).rgb * bg_energy;
		env_ambient *= 1.0 - F;

		ambient_light = mix(ambient_light_color.rgb, env_ambient, radiance_ambient_contribution);
	}
#endif
#endif //AMBIENT_LIGHT_DISABLED

#else

#ifdef AMBIENT_LIGHT_DISABLED
	ambient_light = vec3(0.0, 0.0, 0.0);
#else
	ambient_light = ambient_light_color.rgb;
	env_reflection_light = bg_color.rgb * bg_energy;
#endif //AMBIENT_LIGHT_DISABLED

#endif

	ambient_light *= ambient_energy;

	float specular_blob_intensity = 1.0;

#if defined(SPECULAR_TOON)
	specular_blob_intensity *= specular * 2.0;
#endif

#ifdef USE_GI_PROBES
	gi_probes_compute(vertex, normal, roughness, env_reflection_light, ambient_light);

#endif

#ifdef USE_LIGHTMAP
	ambient_light = texture(lightmap, uv2).rgb * lightmap_energy;
#endif

#ifdef USE_LIGHTMAP_CAPTURE
	{
		vec3 cone_dirs[12] = vec3[](
				vec3(0.0, 0.0, 1.0),
				vec3(0.866025, 0.0, 0.5),
				vec3(0.267617, 0.823639, 0.5),
				vec3(-0.700629, 0.509037, 0.5),
				vec3(-0.700629, -0.509037, 0.5),
				vec3(0.267617, -0.823639, 0.5),
				vec3(0.0, 0.0, -1.0),
				vec3(0.866025, 0.0, -0.5),
				vec3(0.267617, 0.823639, -0.5),
				vec3(-0.700629, 0.509037, -0.5),
				vec3(-0.700629, -0.509037, -0.5),
				vec3(0.267617, -0.823639, -0.5));

		vec3 local_normal = normalize(camera_matrix * vec4(normal, 0.0)).xyz;
		vec4 captured = vec4(0.0);
		float sum = 0.0;
		for (int i = 0; i < 12; i++) {
			float amount = max(0.0, dot(local_normal, cone_dirs[i])); //not correct, but creates a nice wrap around effect
			captured += lightmap_captures[i] * amount;
			sum += amount;
		}

		captured /= sum;

		if (lightmap_capture_sky) {
			ambient_light = mix(ambient_light, captured.rgb, captured.a);
		} else {
			ambient_light = captured.rgb;
		}
	}
#endif

#ifdef USE_FORWARD_LIGHTING

	highp vec4 reflection_accum = vec4(0.0, 0.0, 0.0, 0.0);
	highp vec4 ambient_accum = vec4(0.0, 0.0, 0.0, 0.0);
	for (int i = 0; i < reflection_count; i++) {
		reflection_process(reflection_indices[i], vertex, normal, binormal, tangent, roughness, anisotropy, ambient_light, env_reflection_light, reflection_accum, ambient_accum);
	}

	if (reflection_accum.a > 0.0) {
		specular_light += reflection_accum.rgb / reflection_accum.a;
	} else {
		specular_light += env_reflection_light;
	}
#if !defined(USE_LIGHTMAP) && !defined(USE_LIGHTMAP_CAPTURE)
	if (ambient_accum.a > 0.0) {
		ambient_light = ambient_accum.rgb / ambient_accum.a;
	}
#endif
#endif

	{

#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 a004 = min(r.x * r.x, exp2(-9.28 * ndotv)) * r.x + r.y;
		vec2 env = vec2(-1.04, 1.04) * a004 + r.zw;
		specular_light *= env.x * F + env.y;
#endif
	}

#if defined(USE_LIGHT_DIRECTIONAL)

	vec3 light_attenuation = vec3(1.0);

	float depth_z = -vertex.z;
#ifdef LIGHT_DIRECTIONAL_SHADOW
#if !defined(SHADOWS_DISABLED)

#ifdef LIGHT_USE_PSSM4
	if (depth_z < shadow_split_offsets.w) {
#elif defined(LIGHT_USE_PSSM2)
	if (depth_z < shadow_split_offsets.y) {
#else
	if (depth_z < shadow_split_offsets.x) {
#endif //LIGHT_USE_PSSM4

		vec3 pssm_coord;
		float pssm_fade = 0.0;

#ifdef LIGHT_USE_PSSM_BLEND
		float pssm_blend;
		vec3 pssm_coord2;
		bool use_blend = true;
#endif

#ifdef LIGHT_USE_PSSM4

		if (depth_z < shadow_split_offsets.y) {

			if (depth_z < shadow_split_offsets.x) {

				highp vec4 splane = (shadow_matrix1 * vec4(vertex, 1.0));
				pssm_coord = splane.xyz / splane.w;

#if defined(LIGHT_USE_PSSM_BLEND)

				splane = (shadow_matrix2 * vec4(vertex, 1.0));
				pssm_coord2 = splane.xyz / splane.w;
				pssm_blend = smoothstep(0.0, shadow_split_offsets.x, depth_z);
#endif

			} else {

				highp vec4 splane = (shadow_matrix2 * vec4(vertex, 1.0));
				pssm_coord = splane.xyz / splane.w;

#if defined(LIGHT_USE_PSSM_BLEND)
				splane = (shadow_matrix3 * vec4(vertex, 1.0));
				pssm_coord2 = splane.xyz / splane.w;
				pssm_blend = smoothstep(shadow_split_offsets.x, shadow_split_offsets.y, depth_z);
#endif
			}
		} else {

			if (depth_z < shadow_split_offsets.z) {

				highp vec4 splane = (shadow_matrix3 * vec4(vertex, 1.0));
				pssm_coord = splane.xyz / splane.w;

#if defined(LIGHT_USE_PSSM_BLEND)
				splane = (shadow_matrix4 * vec4(vertex, 1.0));
				pssm_coord2 = splane.xyz / splane.w;
				pssm_blend = smoothstep(shadow_split_offsets.y, shadow_split_offsets.z, depth_z);
#endif

			} else {

				highp vec4 splane = (shadow_matrix4 * vec4(vertex, 1.0));
				pssm_coord = splane.xyz / splane.w;
				pssm_fade = smoothstep(shadow_split_offsets.z, shadow_split_offsets.w, depth_z);

#if defined(LIGHT_USE_PSSM_BLEND)
				use_blend = false;

#endif
			}
		}

#endif //LIGHT_USE_PSSM4

#ifdef LIGHT_USE_PSSM2

		if (depth_z < shadow_split_offsets.x) {

			highp vec4 splane = (shadow_matrix1 * vec4(vertex, 1.0));
			pssm_coord = splane.xyz / splane.w;

#if defined(LIGHT_USE_PSSM_BLEND)

			splane = (shadow_matrix2 * vec4(vertex, 1.0));
			pssm_coord2 = splane.xyz / splane.w;
			pssm_blend = smoothstep(0.0, shadow_split_offsets.x, depth_z);
#endif

		} else {
			highp vec4 splane = (shadow_matrix2 * vec4(vertex, 1.0));
			pssm_coord = splane.xyz / splane.w;
			pssm_fade = smoothstep(shadow_split_offsets.x, shadow_split_offsets.y, depth_z);
#if defined(LIGHT_USE_PSSM_BLEND)
			use_blend = false;

#endif
		}

#endif //LIGHT_USE_PSSM2

#if !defined(LIGHT_USE_PSSM4) && !defined(LIGHT_USE_PSSM2)
		{ //regular orthogonal
			highp vec4 splane = (shadow_matrix1 * vec4(vertex, 1.0));
			pssm_coord = splane.xyz / splane.w;
		}
#endif

		//one one sample

		float shadow = sample_shadow(directional_shadow, directional_shadow_pixel_size, pssm_coord.xy, pssm_coord.z, light_clamp);

#if defined(LIGHT_USE_PSSM_BLEND)

		if (use_blend) {
			shadow = mix(shadow, sample_shadow(directional_shadow, directional_shadow_pixel_size, pssm_coord2.xy, pssm_coord2.z, light_clamp), pssm_blend);
		}
#endif

#ifdef USE_CONTACT_SHADOWS
		if (shadow > 0.01 && shadow_color_contact.a > 0.0) {

			float contact_shadow = contact_shadow_compute(vertex, -light_direction_attenuation.xyz, shadow_color_contact.a);
			shadow = min(shadow, contact_shadow);
		}
#endif
		light_attenuation = mix(mix(shadow_color_contact.rgb, vec3(1.0), shadow), vec3(1.0), pssm_fade);
	}

#endif // !defined(SHADOWS_DISABLED)
#endif //LIGHT_DIRECTIONAL_SHADOW

#ifdef USE_VERTEX_LIGHTING
	diffuse_light *= mix(vec3(1.0), light_attenuation, diffuse_light_interp.a);
	specular_light *= mix(vec3(1.0), light_attenuation, specular_light_interp.a);

#else
	light_compute(normal, -light_direction_attenuation.xyz, eye_vec, binormal, tangent, light_color_energy.rgb, light_attenuation, albedo, transmission, light_params.z * specular_blob_intensity, roughness, metallic, specular, rim, rim_tint, clearcoat, clearcoat_gloss, anisotropy, diffuse_light, specular_light, alpha);
#endif

#endif //#USE_LIGHT_DIRECTIONAL

#ifdef USE_FORWARD_LIGHTING

#ifdef USE_VERTEX_LIGHTING

	diffuse_light *= albedo;
#else

	for (int i = 0; i < omni_light_count; i++) {
		light_process_omni(omni_light_indices[i], vertex, eye_vec, normal, binormal, tangent, albedo, transmission, roughness, metallic, specular, rim, rim_tint, clearcoat, clearcoat_gloss, anisotropy, specular_blob_intensity, diffuse_light, specular_light, alpha);
	}

	for (int i = 0; i < spot_light_count; i++) {
		light_process_spot(spot_light_indices[i], vertex, eye_vec, normal, binormal, tangent, albedo, transmission, roughness, metallic, specular, rim, rim_tint, clearcoat, clearcoat_gloss, anisotropy, specular_blob_intensity, diffuse_light, specular_light, alpha);
	}

#endif //USE_VERTEX_LIGHTING

#endif

#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 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;

	if (fog_color_enabled.a > 0.5) {

		float fog_amount = 0.0;

#ifdef USE_LIGHT_DIRECTIONAL

		vec3 fog_color = mix(fog_color_enabled.rgb, fog_sun_color_amount.rgb, fog_sun_color_amount.a * pow(max(dot(normalize(vertex), -light_direction_attenuation.xyz), 0.0), 8.0));
#else

		vec3 fog_color = fog_color_enabled.rgb;
#endif

		//apply fog

		if (fog_depth_enabled) {
			float fog_far = fog_depth_end > 0.0 ? fog_depth_end : z_far;

			float fog_z = smoothstep(fog_depth_begin, fog_far, length(vertex));

			fog_amount = pow(fog_z, fog_depth_curve) * fog_density;
			if (fog_transmit_enabled) {
				vec3 total_light = emission + ambient_light + specular_light + diffuse_light;
				float transmit = pow(fog_z, fog_transmit_curve);
				fog_color = mix(max(total_light, fog_color), fog_color, transmit);
			}
		}

		if (fog_height_enabled) {
			float y = (camera_matrix * vec4(vertex, 1.0)).y;
			fog_amount = max(fog_amount, pow(smoothstep(fog_height_min, fog_height_max, y), fog_height_curve));
		}

		float rev_amount = 1.0 - fog_amount;

		emission = emission * rev_amount + fog_color * fog_amount;
		ambient_light *= rev_amount;
		specular_light *= rev_amount;
		diffuse_light *= rev_amount;
	}

#ifdef USE_MULTIPLE_RENDER_TARGETS

#ifdef SHADELESS
	diffuse_buffer = vec4(albedo.rgb, 0.0);
	specular_buffer = vec4(0.0);

#else

	//approximate ambient scale for SSAO, since we will lack full ambient
	float max_emission = max(emission.r, max(emission.g, emission.b));
	float max_ambient = max(ambient_light.r, max(ambient_light.g, ambient_light.b));
	float max_diffuse = max(diffuse_light.r, max(diffuse_light.g, diffuse_light.b));
	float total_ambient = max_ambient + max_diffuse + max_emission;
	float ambient_scale = (total_ambient > 0.0) ? (max_ambient + ambient_occlusion_affect_light * max_diffuse) / total_ambient : 0.0;

#if defined(ENABLE_AO)
	ambient_scale = mix(0.0, ambient_scale, ambient_occlusion_affect_ao_channel);
#endif
	diffuse_buffer = vec4(emission + diffuse_light + ambient_light, ambient_scale);
	specular_buffer = vec4(specular_light, metallic);

#endif //SHADELESS

	normal_mr_buffer = vec4(normalize(normal) * 0.5 + 0.5, roughness);

#if defined(ENABLE_SSS)
	sss_buffer = sss_strength;
#endif

#else //USE_MULTIPLE_RENDER_TARGETS

#ifdef SHADELESS
	frag_color = vec4(albedo, alpha);
#else
	frag_color = vec4(emission + ambient_light + diffuse_light + specular_light, alpha);
#endif //SHADELESS

#endif //USE_MULTIPLE_RENDER_TARGETS

#endif //RENDER_DEPTH
}