Class ColorUtils

A set of color manipulation utilities.

Inheritance

Object

ColorUtils

Namespace: UnityEngine.Rendering

Syntax

public static class ColorUtils : object

Fields

s_LensAttenuation

Factor used for our lens system w.r.t. exposure calculation. Modifying this will lead to a change on how linear exposure multipliers are computed from EV100 values (and viceversa). s_LensAttenuation models transmission attenuation and lens vignetting. Note that according to the standard ISO 12232, a lens saturates at s_LensAttenuation = 0.78f (under ISO 100).

Declaration

public static float s_LensAttenuation

Field Value

Type	Description
Single

s_LightMeterCalibrationConstant

Calibration constant (K) used for our virtual reflected light meter. Modifying this will lead to a change on how average scene luminance gets mapped to exposure.

Declaration

public static float s_LightMeterCalibrationConstant

Field Value

Type	Description
Single

Properties

lensImperfectionExposureScale

Scale applied to exposure caused by lens imperfection. It is computed from s_LensAttenuation as follow: (78 / ( S * q )) where S = 100 and q = s_LensAttenuation

Declaration

public static float lensImperfectionExposureScale { get; }

Property Value

Type	Description
Single

Methods

CIExyToLMS(Single, Single)

CIE xy chromaticity to CAT02 LMS. http://en.wikipedia.org/wiki/LMS_color_space#CAT02

Declaration

public static Vector3 CIExyToLMS(float x, float y)

Parameters

Type	Name	Description
Single	x
Single	y

Returns

Type	Description
Vector3

ColorBalanceToLMSCoeffs(Single, Single)

Converts white balancing parameter to LMS coefficients.

Declaration

public static Vector3 ColorBalanceToLMSCoeffs(float temperature, float tint)

Parameters

Type	Name	Description
Single	temperature	A temperature offset, in range [-100;100].
Single	tint	A tint offset, in range [-100;100].

Returns

Type	Description
Vector3	LMS coefficients.

ComputeEV100(Single, Single, Single)

Computes an exposure value (EV100) from physical camera settings.

Declaration

public static float ComputeEV100(float aperture, float shutterSpeed, float ISO)

Parameters

Type	Name	Description
Single	aperture	The camera aperture.
Single	shutterSpeed	The camera exposure time.
Single	ISO	The camera sensor sensitivity.

Returns

Type	Description
Single	An exposure value, in EV100.

ComputeEV100FromAvgLuminance(Single)

Computes an exposure value (EV100) from an average luminance value.

Declaration

public static float ComputeEV100FromAvgLuminance(float avgLuminance)

Parameters

Type	Name	Description
Single	avgLuminance	An average luminance value.

Returns

Type	Description
Single	An exposure value, in EV100.

ComputeISO(Single, Single, Single)

Computes the required ISO to reach targetEV100.

Declaration

public static float ComputeISO(float aperture, float shutterSpeed, float targetEV100)

Parameters

Type	Name	Description
Single	aperture	The camera aperture.
Single	shutterSpeed	The camera exposure time.
Single	targetEV100	The target exposure value (EV100) to reach.

Returns

Type	Description
Single	The required sensor sensitivity (ISO).

ConvertEV100ToExposure(Single)

Converts an exposure value (EV100) to a linear multiplier.

Declaration

public static float ConvertEV100ToExposure(float EV100)

Parameters

Type	Name	Description
Single	EV100	The exposure value to convert, in EV100.

Returns

Type	Description
Single	A linear multiplier.

ConvertExposureToEV100(Single)

Converts a linear multiplier to an exposure value (EV100).

Declaration

public static float ConvertExposureToEV100(float exposure)

Parameters

Type	Name	Description
Single	exposure	A linear multiplier.

Returns

Type	Description
Single	An exposure value, in EV100.

Luminance(in Color)

Returns the luminance of the specified color. The input is considered to be in linear space with sRGB primaries and a D65 white point.

Declaration

public static float Luminance(in Color color)

Parameters

Type	Name	Description
Color	color	The color to compute the luminance for.

Returns

Type	Description
Single	A luminance value.

PrepareLiftGammaGain(in Vector4, in Vector4, in Vector4)

Pre-filters lift, gamma and gain trackball values for shader use.

Declaration

public static (Vector4, Vector4, Vector4) PrepareLiftGammaGain(in Vector4 inLift, in Vector4 inGamma, in Vector4 inGain)

Parameters

Type	Name	Description
Vector4	inLift	A color used for lift.
Vector4	inGamma	A color used for gamma.
Vector4	inGain	A color used for gain.

Returns

Type	Description
(, , )<Vector4, Vector4, Vector4>	The three input colors pre-filtered for shader use.

PrepareShadowsMidtonesHighlights(in Vector4, in Vector4, in Vector4)

Pre-filters shadows, midtones and highlights trackball values for shader use.

Declaration

public static (Vector4, Vector4, Vector4) PrepareShadowsMidtonesHighlights(in Vector4 inShadows, in Vector4 inMidtones, in Vector4 inHighlights)

Parameters

Type	Name	Description
Vector4	inShadows	A color used for shadows.
Vector4	inMidtones	A color used for midtones.
Vector4	inHighlights	A color used for highlights.

Returns

Type	Description
(, , )<Vector4, Vector4, Vector4>	The three input colors pre-filtered for shader use.

PrepareSplitToning(in Vector4, in Vector4, Single)

Pre-filters colors used for the split toning effect.

Declaration

public static (Vector4, Vector4) PrepareSplitToning(in Vector4 inShadows, in Vector4 inHighlights, float balance)

Parameters

Type	Name	Description
Vector4	inShadows	A color used for shadows.
Vector4	inHighlights	A color used for highlights.
Single	balance	The balance between the shadow and highlight colors, in range [-100;100].

Returns

Type	Description
(, )<Vector4, Vector4>	The two input colors pre-filtered for shader use.

StandardIlluminantY(Single)

An analytical model of chromaticity of the standard illuminant, by Judd et al. http://en.wikipedia.org/wiki/Standard_illuminant#Illuminant_series_D Slightly modifed to adjust it with the D65 white point (x=0.31271, y=0.32902).

Declaration

public static float StandardIlluminantY(float x)

Parameters

Type	Name	Description
Single	x

Returns

Type	Description
Single

ToHex(Color)

Converts a color value to its 32-bit hexadecimal representation.

Declaration

public static uint ToHex(Color c)

Parameters

Type	Name	Description
Color	c	The color to convert.

Returns

Type	Description
UInt32	A 32-bit hexadecimal representation of the color.

ToRGBA(UInt32)

Converts a 32-bit hexadecimal value to a color value.

Declaration

public static Color ToRGBA(uint hex)

Parameters

Type	Name	Description
UInt32	hex	A 32-bit hexadecimal value.

Returns

Type	Description
Color	A color value.