UUSL Data Types and Common Intrinsic Functions

This documentation article contains information about data types, functions, pre-defined variables and other features of the UUSL. This information can be used as the reference document for writing shaders.

To start using UUSL functions, include the core/shaders/common/common.h file.

#include <core/shaders/common/common.h>

For fragment shader functions, use the core/shaders/common/fragment.h file.

Predefined Values

Void Main Function

MAIN_VOID_BEGIN(STRUCT_IN)
	<your code here>
MAIN_VOID_END

void main() {
	<your code here>
}

void main(STRUCT_IN IN) {
	<your code here>
}

Main Function with Return Value

MAIN_BEGIN(STRUCT_IN,STRUCT_OUT)
	<your code here>
MAIN_END

void main() {
	<your code here>
}

STRUCT_OUT main(STRUCT_IN IN) { 
	STRUCT_OUT OUT;
	<your code here>
return OUT; }

Geometry Shader Main Function

MAIN_GEOM_BEGIN(STRUCT_OUT,STRUCT_IN)
	<your code here>
END_GEOM

layout(TYPE_GEOM_IN) in;
layout(TYPE_GEOM_OUT,max_vertices = MAX_VERTICES_GEOM) out;
void main() {
	<your code here>
}

[maxvertexcount(MAX_VERTICES_GEOM)]
void main(TYPE_GEOM_IN STRUCT_IN IN[COUNT_GEOM_IN],inout TYPE_GEOM_OUT<STRUCT_OUT> stream) {
	STRUCT_OUT OUT;
	<your code here>
}

Static Variables

STATICVAR <your var>

const <your var>

static const <your var>

Static Arrays

STATICARRAY(TYPE,NAME,SIZE)
	<your array members>
ENDARRAY

TYPE NAME [SIZE] = TYPE[](<your array members>);

static const TYPE NAME [SIZE] = {<your array members>};

UUSL contains blending presets. When you specify the type of blending in material, the USSL wrapper automatically defines a new definition, that you can use in your shader:

HLSL Flow Control Attributes

Interpolation Modifiers

In USSL structures is the way to organize the bunch of input and output data.

To start using structures in your shader code, use the following instructions:

STRUCT(NAME)
	<your data>
END

• NAME - the name of the struct.

Here is an example of vertex shader input structure:

// Input vertex data
STRUCT(VERTEX_IN)
	INIT_ATTRIBUTE(float4,0,POSITION)	// Vertex position
	INIT_ATTRIBUTE(float4,1,TEXCOORD0)	// Vertex texcoord (uv)
	INIT_ATTRIBUTE(float4,2,TEXCOORD1)	// Vertex basis tangent
	INIT_ATTRIBUTE(float4,3,TEXCOORD2)	// Vertex color
END

After that, you should pass the VERTEX_IN structure to the main function of the vertex shader.

For using constant buffer in your shader code, use the following instructions:

CBUFFER(NAME)
	<your data>
END

• NAME - the name of the cbuffer.

Here is an example of using constant buffer:

CBUFFER(parameters)
	UNIFORM float grayscale_power;
END

If you defined this parameter in the material, you'll be able to specify this value.

See Also

To export shader, use the following command:

EXPORT_SHADER(FILE)

• FILE - The name of the file.

This command exports the shader program into a file: for Direct3D the file will have an .hlsl extension, for OpenGL the file will have an .glsl extension.

The command expands all of the predefined UUSL syntax and creates shader files in native languages for both graphic APIs.

fmod (value X, value Y)

Equivalents

mod(X,Y)

fmod(X,Y)

Arguments

• value X - The dividend value.
• value Y - The divisor value.

frac (value value)

Equivalents

fract(value)

frac(value)

Arguments

• value value - The specified value.

lerp (value X, value Y, value value)

Equivalents

mix(X,Y,value)

lerp(X,Y,value)

Arguments

• value X - The first value.
• value Y - The second value.
• value value - A value that linearly interpolates between the x parameter and the y parameter.

lerpOne (float value, float factor)

Equivalents

value * (1.0f - factor) + factor;

value * (1.0f - factor) + factor;

Arguments

• float value - Value.
• float factor - Interpolation factor.

float length2 (float3 vector)

Arguments

• float3 vector - Vector.

Return value

float getBasisX (float3x3 matrix)

Equivalents

m[0];

m._m00_m10_m20;

Arguments

• float3x3 matrix - 3x3 matrix.

Return value

float getBasisX (float4x4 matrix)

Equivalents

m[0].xyz;

m._m00_m10_m20;

Arguments

• float4x4 matrix - 3x3 matrix.

Return value

float getBasisY (float3x3 matrix)

Equivalents

m[1];

m._m01_m11_m21;

Arguments

• float3x3 matrix - 3x3 matrix.

Return value

float getBasisY (float4x4 matrix)

Equivalents

m[1].xyz;

m._m01_m11_m21;

Arguments

• float4x4 matrix - 3x3 matrix.

Return value

float getBasisZ (float3x3 matrix)

Equivalents

m[2];

m._m02_m12_m22;

Arguments

• float3x3 matrix - 3x3 matrix.

Return value

float getBasisZ (float4x4 matrix)

Equivalents

m[2].xyz;

m._m02_m12_m22;

Arguments

• float4x4 matrix - 3x3 matrix.

Return value

rsqrt (value value)

Equivalents

inversesqrt(value)

rsqrt(value)

Arguments

• value value - The specified value.

saturate (value value)

Equivalents

clamp(value,0.0f,1.0f)

saturate(value)

Arguments

• value value - The specified value.

ddx (value value)

Equivalents

dFdx(value)

ddx(value)

Arguments

• value value - The specified value.

ddy (value value)

Equivalents

dFdy(value)

ddy(value)

Arguments

• value value - The specified value.

rcp (value value)

Equivalents

(1.0f / (value))

rcp(value)

Arguments

• value value - The specified value.

equal (value X, value Y)

Equivalents

equal(X,Y)

(X == Y)

Arguments

• value X - The first specified value.
• value Y - The second specified value.

greaterThan (value X, value Y)

Equivalents

greaterThan(X,Y)

(X > Y)

Arguments

• value X - The first specified value.
• value Y - The second specified value.

atan2 (value X, value Y)

Equivalents

atan(X,Y)

atan2(X,Y)

Arguments

• value X - The first specified value.
• value Y - The second specified value.

any (value value)

Equivalents

(value)

any(value)

Arguments

• value value - The specified value.

float max2 (value value)

Equivalents

max(value.r,value.g)

max(value.r,value.g)

Arguments

• value value - The specified vector (can be float2, float3 or float4 vector).

Return value

float max3 (value value)

Equivalents

max(max(value.r,value.g),value.b)

max(max(value.r,value.g),value.b)

Arguments

• value value - The specified vector (can be float3 or float4).

Return value

float max4 (float4 value)

Equivalents

max(max(max(value.r,value.g),value.b),value.a)

max(max(max(value.r,value.g),value.b),value.a)

Arguments

• float4 value - The specified vector.

Return value

float min2 (value value)

Equivalents

min(value.r,value.g)

min(value.r,value.g)

Arguments

• value value - The specified vector (can be float2, float3 or float4 vector).

Return value

float min3 (value value)

Equivalents

min(min(value.r,value.g),value.b)

min(min(value.r,value.g),value.b)

Arguments

• value value - The specified vector (can be float3 or float4 vector).

Return value

float min4 (float4 value)

Equivalents

min(min(min(value.r,value.g),value.b),value.a)

min(min(min(value.r,value.g),value.b),value.a)

Arguments

• float4 value - The specified vector.

Return value

value pow2 (value value)

Equivalents

value * value

value * value

Arguments

• value value - The specified value to be powered (can be float, float2, float3 or float4.

Return value

float nrand (float2 seed)

Equivalents

frac(sin(dot(seed,float2(12.9898f,78.233f))) * 43758.5453f)

frac(sin(dot(seed,float2(12.9898f,78.233f))) * 43758.5453f)

Arguments

• float2 seed - The random seed.

Return value

float2 nrand (float2 seed_0, float2 seed_1)

Arguments

• float2 seed_0 - The first random seed.
• float2 seed_1 - The second random seed.

Return value

float2 nrand2 (float2 seed)

Arguments

• float2 seed - The random seed.

Return value

float nrandTiled (float2 seed_0, flaot tiled)

Arguments

• float2 seed_0 - The first random seed.
• flaot tiled - The seed of tiling (the number should be the power of two).

Return value

float2 nrandTiled (float2 seed_0, float2 seed_1, float tiled)

Arguments

• float2 seed_0 - The first random seed.
• float2 seed_1 - The second random seed.
• float tiled - The seed of tiling (the number should be the power of two).

Return value

float2 nrand2Tiled (float2 seed, float tiled)

Arguments

• float2 seed - The random seed.
• float tiled - The seed of tiling (the number should be the power of two).

Return value

float nrandTemporal (float2 seed_0, flaot tiled)

Arguments

• float2 seed_0 - The first random seed.
• flaot tiled - The seed of tiling (the number should be the power of two).

Return value

float2 nrandTemporal (float2 seed_0, float2 seed_1, float tiled)

Arguments

• float2 seed_0 - The first random seed.
• float2 seed_1 - The second random seed.
• float tiled - The seed of tiling (the number should be the power of two).

Return value

float2 nrand2Temporal (float2 seed, float tiled)

Arguments

• float2 seed - The random seed.
• float tiled - The seed of tiling (the number should be the power of two).

Return value

float nrandTAA (float2 seed_0, flaot tiled)

Arguments

• float2 seed_0 - The first random seed.
• flaot tiled - The seed of tiling (the number should be the power of two).

Return value

float2 nrandTAA (float2 seed_0, float2 seed_1, float tiled)

Arguments

• float2 seed_0 - The first random seed.
• float2 seed_1 - The second random seed.
• float tiled - The seed of tiling (the number should be the power of two).

Return value

float2 nrand2TAA (float2 seed, float tiled)

Arguments

• float2 seed - The random seed.
• float tiled - The seed of tiling (the number should be the power of two).

Return value

dotFixed (value X, value Y)

Equivalents

saturate(dot(X,Y))

saturate(dot(X,Y)))

Arguments

• value X - The first specified vector.
• value Y - The second specified vector.

lerpFixed (value X, value Y, value FACTOR)

Equivalents

lerp(X,Y,saturate(FACTOR))

lerp(X,Y,saturate(FACTOR))

Arguments

• value X - The first specified vector.
• value Y - The second specified vector.
• value FACTOR - A value that linearly interpolates between the x parameter and the y parameter.

float4 getPosition (value vertex)

Arguments

• value vertex - The first specified vertex (float4 or float3 type).

Return value

float3 getViewDirection (value screen_position)

float3((position + s_perspective.zw) / s_perspective.xy,-1.0f);

float3((position + s_perspective.zw) / s_perspective.xy,-1.0f);

Arguments

• value screen_position - Position (float2, float3 or float3 type).

Return value

void getTangentBasis (float4 basis, float3 out tangent, float3 out binormal, float3 out normal)

// Get normals
float3 tangent,binormal,normal;

// Getting normal in object-space
getTangentBasis(IN_ATTRIBUTE(2),tangent,binormal,normal);

// Transform object-space TBN into camera-space TBN
normal = normalize(mul3(row_0,row_1,row_2,normal));
tangent = normalize(mul3(row_0,row_1,row_2,tangent));
binormal = normalize(mul3(row_0,row_1,row_2,binormal));

Arguments

• float4 basis - Basis vector.
• float3 out tangent - Empty vector for tangent.
• float3 out binormal - Empty vector for binormal.
• float3 out normal - Empty vector for normal.

void getTangentBasis (float4 basis, float3 out tangent, float3 out normal)

Arguments

• float4 basis - Basis vector.
• float3 out tangent - Empty vector for tangent.
• float3 out normal - Empty vector for normal.

float3 mul (float3 vector, float3x3 matrix)

Arguments

• float3 vector - The 3-component vector.
• float3x3 matrix - The 3x3 matrix.

Return value

float3 mul (float3x3 matrix, float3 vector)

Arguments

• float3x3 matrix - The 3x3 matrix.
• float3 vector - The 3-component vector.

Return value

float4 mul (float4 vector, float4x4 matrix)

Arguments

• float4 vector - The 4-component vector.
• float4x4 matrix - The 4x4 matrix.

Return value

float4 mul (float4x4 matrix, float4 vector)

Arguments

• float4x4 matrix - The 4x4 matrix.
• float4 vector - The 4-component vector.

Return value

float3 mul3 (float4x4 matrix, float3 vector)

Arguments

• float4x4 matrix - The 4x4 matrix.
• float3 vector - The 3-component vector.

Return value

float3 mul3 (float3 vector, float4x4 matrix)

Arguments

• float3 vector - The 3-component vector.
• float4x4 matrix - The 4x4 matrix.

Return value

float3 mul3 (float4 row_0, float4 row_1, float4 row_2, float3 vector)

Arguments

• float4 row_0 - The first row of the matrix
• float4 row_1 - The second row of the matrix
• float4 row_2 - The third row of the matrix
• float3 vector - The 3-component vector.

Return value

float3 mul3 (float3x3 matrix, float3 vector)

Arguments

• float3x3 matrix - The 3x3 matrix.
• float3 vector - The 3-component vector.

Return value

float4 mul4 (float4x4 matrix, float3 vector)

(m * float4(v,1.0f)).xyz;

(m * float4(v,1.0f)).xyz;

Arguments

• float4x4 matrix - The 4x4 matrix.
• float3 vector - The 3-component vector.

Return value

float4 mul4 (float4x4 matrix, float4 vector)

Arguments

• float4x4 matrix - The 4x4 matrix.
• float4 vector - The 4-component vector.

Return value

float4 mul4 (float4 row_0, float4 row_1, float4 row_2, float3 vector)

float4(dot(row_0,v),dot(row_1,v),dot(row_2,v),v.w);

float4(dot(row_0,v),dot(row_1,v),dot(row_2,v),v.w);

Arguments

• float4 row_0 - The first row of the matrix
• float4 row_1 - The second row of the matrix
• float4 row_2 - The third row of the matrix
• float3 vector - The 4-component vector.

Return value

float floatPack88To16 (float2 value)

Arguments

• float2 value - Value to pack.

Return value

float2 floatPack16To88 (float value)

Arguments

• float value - Value to pack.

Return value

float2 floatPack8888To1616 (float4 value)

Arguments

• float4 value - Value to pack.

Return value

float4 floatPack1616To8888 (float2 value)

Arguments

• float2 value - Value to pack.

Return value

float3 floatPack1212To888 (float2 value)

Arguments

• float2 value - Value to pack.

Return value

float2 floatPack888To1212 (float3 value)

Arguments

• float3 value - Value to pack.

Return value

SET_DEPTH (value value)

Arguments

• value value - Depth value.

SET_DIFFUSE (value value)

Arguments

• value value - Diffuse value.

SET_MICROFIBER (value value)

Arguments

• value value - Microfiber value.

SET_NORMAL (value value)

Arguments

• value value - Normal value.

SET_GLOSS (value value)

Arguments

• value value - Gloss value.

SET_SPECULAR (value value)

Arguments

• value value - Specular value.

SET_TRANSLUCENT (value value)

Arguments

• value value - Translucent value.

SET_OCCLUSION (value value)

Arguments

• value value - Occlusion value.

SET_LIGHT_MAP (value value)

Arguments

• value value - Lightmap value.

SET_DECAL_MASK (value value)

Arguments

• value value - Decal mask value.

SET_VELOCITY (value value)

Arguments

• value value - Velocity value.

SET_ALPHA (value value)

Arguments

• value value - Alpha value.

float GET_DEFERRED_DEPTH (value TEX_DEPTH, value COORD)

Arguments

• value TEX_DEPTH - Depth texture slot.
• value COORD - UV coordinates.

Return value

float FETCH_DEFERRED_DEPTH (value TEX_DEPTH, value COORD)

Arguments

• value TEX_DEPTH - Depth texture slot.
• value COORD - UV coordinates.

Return value

float3 specularReflection (float4 specular, float dotVN)

Arguments

• float4 specular - Specular value.
• float dotVN - Dot product of 2 vectors: normal vector and vector to camera.

Return value

float3 conserveEnergy (float3 diffuse, float4 specular, float dotVN)

Arguments

• float3 diffuse - Diffuse value
• float4 specular - Specular value.
• float dotVN - Dot product of 2 vectors: normal vector and vector to camera.

Return value

float2 getBRDF (float4 specular, float translucent_scale, float3 N, float3 L, float3 V)

Arguments

• float4 specular - Specular value.
• float translucent_scale - Translucent scale value.
• float3 N - Normal vector.
• float3 L - Direction vector to light source.
• float3 V - Direction vector to camera.

Return value

float2 getBRDF (float gloss, float F0, float translucent_scale, float dotNV, float dotVH, float dotNL, float dotNH, float dotVL)

Arguments

• float gloss - Gloss value.
• float F0 - Reflectance for H·V = 1.
• float translucent_scale - Translucent scale value.
• float dotNV - Dot product of 2 vectors: normal vector and vector to camera.
• float dotVH - Dot product of 2 vectors: vector to camera and normalized halfway vector (H = (V + L) / |V + L|).
• float dotNL - Dot product of 2 vectors: normal vector and vector to light source.
• float dotNH - Dot product of 2 vectors: normal vector and normalized halfway vector (H = (V + L) / |V + L|).
• float dotVL - Dot product of 2 vectors: vector to camera and vector to light source.

Return value

float2 getBRDF (float gloss, float F0, float translucent_scale, float3 N, float3 L, float3 V)

Arguments

• float gloss - Gloss value.
• float F0 - Reflectance for H·V = 1.
• float translucent_scale - Translucent scale value.
• float3 N - Normal vector.
• float3 L - Direction vector to light source.
• float3 V - Direction vector to camera.

Return value

float getFresnelSchlick (float3 F0, float3 dotLH)

Arguments

• float3 F0 - Reflectance for H·V = 1.
• float3 dotLH - Dot product of 2 vectors: vector to light source and normalized halfway vector (H = (V + L) / |V + L|).

Return value

float getGGX (float roughness, float dotNV, float dotNL, float dotNH)

Arguments

• float roughness - Roughness value.
• float dotNV - Dot product of 2 vectors: normal vector and vector to camera.
• float dotNL - Dot product of 2 vectors: normal vector and vector to light source.
• float dotNH - Dot product of 2 vectors: normal vector and normalized halfway vector (H = (V + L) / |V + L|).

Return value

float getGGX (float roughness, float dotNV, float dotNL, float dotNH, float translucent_scale)

Arguments

• float roughness - Roughness value.
• float dotNV - Dot product of 2 vectors: normal vector and vector to camera.
• float dotNL - Dot product of 2 vectors: normal vector and vector to light source.
• float dotNH - Dot product of 2 vectors: normal vector and normalized halfway vector (H = (V + L) / |V + L|).
• float translucent_scale - Translucent scale value.

Return value

float getAreaLightGGX (float roughness, float dotNV, float dotNL, float dotLR, float size)

Arguments

• float roughness - Roughness value.
• float dotNV - Dot product of 2 vectors: normal vector and vector to camera.
• float dotNL - Dot product of 2 vectors: normal vector and vector to light source.
• float dotLR - Dot product of 2 vectors: normal vector and reflected vector.
• float size - The size of specular lighting.

Return value

float getAreaLightGGX (float roughness, float dotNV, float dotNL, float dotLR, float size, float translucent_scale)

Arguments

• float roughness - Roughness value.
• float dotNV - Dot product of 2 vectors: normal vector and vector to camera.
• float dotNL - Dot product of 2 vectors: normal vector and vector to light source.
• float dotLR - Dot product of 2 vectors: vector to light source and reflected vector.
• float size - The size of specular lighting.
• float translucent_scale - Translucent scale value.

Return value

float getPhong (float dotLR, float power)

Arguments

• float dotLR - Dot product of 2 vectors: normal vector and reflected vector.
• float power - The specular power value.

Return value

float getBlinn (float dotNH, float power)

Arguments

• float dotNH - Dot product of 2 vectors: normal vector and normalized halfway vector (H = (V + L) / |V + L|).
• float power - The specular power value.

Return value

float getLightAttenuation (float3 position)

Arguments

• float3 position - Position value.

Return value

float getLightAttenuation (float light_distance)

Arguments

• float light_distance - Light Distance value.

Return value

float getBarley12 (float roughness, float dotNV, float dotVH, float dotNL)

Arguments

• float roughness - Roughness value.
• float dotNV - Dot product of 2 vectors: normal vector and vector to camera.
• float dotVH - Dot product of 2 vectors: vector to camera and normalized halfway vector (H = (V + L) / |V + L|).
• float dotNL - Dot product of 2 vectors: normal vector and vector to light source.

Return value

float getWrapAround (float dotNL, float factor)

Arguments

• float dotNL - Dot product of 2 vectors: normal vector and vector to light source.
• float factor - Energy conservation factor.

Return value

float getTranslucent (float translucent_scale, float dotVL, float dotNL)

Arguments

• float translucent_scale - Translucent scale value.
• float dotVL - Dot product of 2 vectors: vector to camera and vector to light source.
• float dotNL - Dot product of 2 vectors: normal vector and vector to light source.

Return value

float3 sphereLightToLight (float3 L, float3 direction)

Arguments

• float3 L - Vector to the light source.
• float3 direction - Shift direction vector.

Return value

float3 capsuleLightToLight (float3 L, float3 direction, float3 axis)

Arguments

• float3 L - Vector to the light source.
• float3 direction - Shift direction vector.
• float3 axis - Axis of shift.

Return value

Here is an example of scattering functions usage:

#ifdef USE_HAZE
	#ifdef USE_HAZE_SCATTERING
		float4 haze = hazeScattering(depth,camera_dir,TEXTURE_OUT_3(TEX_BASE_LUT,TEX_MIE_SUN_LUT,TEX_MIE_MOON_LUT));
	#elif USE_HAZE_SOLID
		float4 haze = hazeSolid(depth);
	#endif
	
	OUT_COLOR.rgb = OUT_COLOR.rgb * haze.a + haze.rgb;
#endif

// forward
#ifdef USE_HAZE && !STAR_AMBIENT
	OUT_COLOR = hazeForward(OUT_COLOR,depth,camera_dir,TEXTURE_OUT_3(TEX_BASE_LUT,TEX_MIE_SUN_LUT,TEX_MIE_MOON_LUT));
#endif

float4 hazeScattering (float depth, float3 camera_dir, TEXTURE_IN_3 (base,mie_sun,mie_moon))

Arguments

• float depth - Depth value.
• float3 camera_dir - Camera direction vector.
• TEXTURE_IN_3 (base,mie_sun,mie_moon) - Set of 3 LUT textures: base, mie sun and mie moon.

Return value

float4 hazeForward (float4 color, float depth, float3 camera_dir, TEXTURE_IN_3 (base,mie_sun,mie_moon))

Arguments

• float4 color - Color
• float depth - Depth value.
• float3 camera_dir - Camera direction vector.
• TEXTURE_IN_3 (base,mie_sun,mie_moon) - Set of 3 LUT textures: base, mie sun and mie moon.

Return value

float hazeAlpha (float depth)

Arguments

• float depth - Depth value.

Return value

float hazeAlpha (float3 position)

Arguments

• float3 position - Position.

Return value

float hazeAlpha (float4 position)

Arguments

• float4 position - Position.

Return value

float4 hazeSolid (float depth)

Arguments

• float depth - Depth value.

Return value

float4 hazeSolid (float position)

Arguments

• float position - Position.

Return value

float4 hazeSolid (float position)

Arguments

• float position - Position.

Return value

float4 hazeForwardSimple (float4 color, float depth)

Arguments

• float4 color - Color vector.
• float depth - Depth value.

Return value

float4 hazeForwardSimple (float4 color, float3 position)

Arguments

• float4 color - Color vector.
• float3 position - Position.

Return value

float4 hazeForwardSimple (float4 color, float4 position)

Arguments

• float4 color - Color vector.
• float4 position - Position.

Return value