Class: TXYZColor

Declaration: XYZColor.h

Taxonomy Categories:

Member Functions:


Interface Category:

API.

Inherits From:

TColor

Inherited By:

None.

Purpose:

TXYZColor, derived from TColor, defines a tristimulus device-independent color space (in other words, a calibrated color space) whose values are standardized internationally by the CIE (Commission Internationale de l'Eclairage). A TXYZColor is absolute in the sense that its tristimulus coordinates (X, Y, and Z) uniquely define a color. The X, Y, and Z primaries can be used to represent all visible colors. TXYZColors is one of the cornerstones for the color architecture, because every color that is derived from TColor must be able to convert itself to a TXYZColor. Note that although TXYZColors are useful for color reproduction, they are not very good for evaluating relative change in color. The TXYZColor space is perceptually nonlinear. The class provides arithmetic operators that operate on two colors.

Instantiation:

Allocate on the heap or the stack.

Deriving Classes:

TSpectralColor is provided. Derive new color models from TColor.

Concurrency:

Multithread safe.

Resource Use:

No special requirements.

Member Function: TXYZColor::TXYZColor

  1. TXYZColor ()
  2. TXYZColor (TColorProfile * theDeviceColorProfile)
  3. TXYZColor (TristimulusCoord aX, TristimulusCoord aY, TristimulusCoord aZ, GIntensity opacity =1.0)
  4. TXYZColor (const TXYZColor & aXYZColor)
  5. TXYZColor (TColorProfile * theDeviceColorProfile, TristimulusCoord aX, TristimulusCoord aY, TristimulusCoord aZ, GIntensity opacity =1.0)

Interface Category:

API.

Purpose:

  1. Default constructor; it has the default color profile, and color components are not initialized.
  2. Creates a XYZColor with the specified color profile. The color components are not initialized.
  3. Creates a XYZColor with the specified components. It has the default color profile.
  4. Copy constructor.
  5. Creates a XYZColor with the specified components and color profile.

Calling Context:

  1. Called by the stream-in operators. You can also call this function directly.
  2. Call this function directly.
  3. Call this function directly.
  4. Called to copy an object. You can also call this function directly.
  5. Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::GetComponents

void GetComponents (TristimulusCoord & aX, TristimulusCoord & aY, TristimulusCoord & aZ, GIntensity & opacity) const

Interface Category:

API.

Purpose:

Gets the X, Y, and Z components of this TXYZColor and returns them in the specified parameters.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::GetClampedComponents

void GetClampedComponents (TristimulusCoord & aX, TristimulusCoord & aY, TristimulusCoord & aZ, GIntensity & opacity) const

Interface Category:

API.

Purpose:

Gets the components of this TXYZColor clamped between 0.0 <= N <= 1.0.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::GetX

TristimulusCoord GetX () const

Interface Category:

API.

Purpose:

Gets the X component of this TXYZColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns the X component of the color.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::GetY

TristimulusCoord GetY () const

Interface Category:

API.

Purpose:

Returns the Y component of this TXYZColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns the Y component of the color.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::GetZ

TristimulusCoord GetZ () const

Interface Category:

API.

Purpose:

Returns the Z component of this TXYZColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns the Z component of the color.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::GetColorDifference

GCoordinate GetColorDifference (const TXYZColor & aColor2) const

Interface Category:

API.

Purpose:

Calculates the color difference between this TXYZColor and the specified one. The color difference is defined as the sqrt( (X1-X2)^2+(Y1-Y2)^2+(Z1-Z2)^2 ).

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns the value of the color difference between the two colors.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::SetComponents

void SetComponents (TristimulusCoord aX, TristimulusCoord aY, TristimulusCoord aZ, GIntensity opacity =1.0)

Interface Category:

API.

Purpose:

Sets the components of this TXYZColor to the specified parameters.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::SetY

void SetY (TristimulusCoord aY)

Interface Category:

API.

Purpose:

Sets the Y component of this TXYZColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::SetZ

void SetZ (TristimulusCoord aZ)

Interface Category:

API.

Purpose:

Sets the Z component of this TXYZColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::operatorTRGBColor

virtual operator TRGBColor () const

Interface Category:

API.

Purpose:

Casts this TXYZColor to a TRGBColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns a TRGBColor that corresponds to this color.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::operatorTXYZColor

virtual operator TXYZColor () const

Interface Category:

API.

Purpose:

Casts this TXYZColor to a TXYZColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns a TXYZColor that corresponds to this color.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

Not strictly useful, but necessary for orthogonality.

Member Function: TXYZColor::operator=

  1. TXYZColor & operator =(const TXYZColor & aSource)
  2. TColor & operator =(const TColor & aSource)

Interface Category:

API.

Purpose:

  1. Assignment operator.
  2. Assignment operator that casts the specified operand to a TXYZColor.

Calling Context:

  1. Called when an object is assigned to another compatible object.
  2. Called when an object is assigned to another compatible object.

Parameters:

Return Value:

A non-const reference to the left-hand side object.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::operator+

  1. TXYZColor operator + (const TXYZColor & aColor2) const
  2. TXYZColor operator + (const float aScalar) const

Interface Category:

API.

Purpose:

  1. Adds the components of the two TXYZColors together.
  2. Adds the specified scalar to each component of this TXYZColor.

Calling Context:

  1. Call this operator directly.
  2. Call this operator directly.

Parameters:

Return Value:

  1. Returns a new color with the new components.
  2. Returns a new color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The values of the components are not clamped to the range 0.0 <= N <= 1.0.

Member Function: TXYZColor::operator-

  1. TXYZColor operator -(const TXYZColor & aColor2) const
  2. TXYZColor operator -(const float aScalar) const

Interface Category:

API.

Purpose:

  1. Subtracts the components of the specified color from this TXYZColor.
  2. Subtracts the specified scalar from each component of this TXYZColor.

Calling Context:

  1. Call this operator directly.
  2. Call this operator directly.

Parameters:

Return Value:

  1. Returns a new color with the new components.
  2. Returns a new color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The values of the components are not clamped to the range 0.0 <= N <= 1.0.

Member Function: TXYZColor::operator*

  1. TXYZColor operator * (const float aScalar) const
  2. TXYZColor operator * (const TXYZColor & aColor2) const

Interface Category:

API.

Purpose:

  1. Multiplies each component of this TXYZColor by the specified scalar.
  2. Multiplies the components of this TXYZColor by the components of the specified color.

Calling Context:

  1. Call this operator directly.
  2. Call this operator directly.

Parameters:

Return Value:

  1. Returns a new color with the new components.
  2. Returns a new color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The values of the components are not clamped to the range 0.0 <= N <= 1.0.

Member Function: TXYZColor::operator/=

TXYZColor & operator /= (const float aScalar)

Interface Category:

API.

Purpose:

Divides the components of this TXYZColor by the specified scalar and assigns the new values to the respective components.

Calling Context:

Call this operator directly.

Parameters:

Return Value:

Returns this color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::operator+=

  1. TXYZColor & operator += (const float aScalar)
  2. TXYZColor & operator += (const TXYZColor & aColor2)

Interface Category:

API.

Purpose:

  1. Adds the specified scalar to the components of this TXYZColor and assigns the new values to the respective components.
  2. Adds the specified colors to the components of this TXYZColor and assigns the new values to the respective components.

Calling Context:

  1. Call this operator directly.
  2. Call this operator directly.

Parameters:

Return Value:

  1. Returns this color with the new components.
  2. Returns this color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::operator-=

  1. TXYZColor & operator -=(const float aScalar)
  2. TXYZColor & operator -=(const TXYZColor & aColor2)

Interface Category:

API.

Purpose:

  1. Subtracts the specified scalar from the components of this TXYZColor and assigns the new values to the respective components.
  2. Subtracts the specified scalar from the components of this TXYZColor and assigns the new values to the respective components.

Calling Context:

  1. Call this operator directly.
  2. Call this operator directly.

Parameters:

Return Value:

  1. Returns this color with the new components.
  2. Returns this color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::operator*=

TXYZColor & operator *= (const float aScalar)

Interface Category:

API.

Purpose:

Multiplies the components of this TXYZColor by the specified scalar and assigns the new values to the respective components.

Calling Context:

Call this operator directly.

Parameters:

Return Value:

Returns this color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::operator/

TXYZColor operator / (const float aScalar) const

Interface Category:

API.

Purpose:

Divides each component of this TXYZColor by the specified scalar.

Calling Context:

Call this operator directly.

Parameters:

Return Value:

Returns a color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::FuzzyCompare

  1. bool FuzzyCompare (const TXYZColor & aXYZColor, float acceptableErrorPerComponent =0.0001) const
  2. bool FuzzyCompare (const TXYZColor & aXYZColor, float errOpacity, float errX, float errY, float errZ) const

Interface Category:

API.

Purpose:

  1. Compares this TXYZColor and the specified color with reference to the specified tolerance. It takes the absolute difference between the components of the color and compares them to a known value.
  2. Compares this TXYZColor and the specified color to a given accuracy on a component by component level.

Calling Context:

  1. Call this function directly.
  2. Call this function directly.

Parameters:

Return Value:

  1. Returns true if the two colors are equal with reference to the specified tolerance.
  2. Returns true if the two colors are equal with reference to the specified tolerance.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::LinearInterpolate

void LinearInterpolate (const float aWeight, const TXYZColor & aColor2)

Interface Category:

API.

Purpose:

Makes a weighted linear interpolation of each component of this TXYZColor. The interpolation is returned in this color. The interpolation that is done for each component is (using X as an example) given by X1 =X1 + (X2 -X1) * Weight.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::AddAndPin

void AddAndPin (const TXYZColor & aColor2)

Interface Category:

API.

Purpose:

Adds the specified color to this TXYZColor and then clamps the resulting values of the components.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::SubtractAndPin

void SubtractAndPin (const TXYZColor & aColor2)

Interface Category:

API.

Purpose:

Subtracts the specified color from this TXYZColor and then clamps the resulting values of the components.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::Maximum

void Maximum (const TXYZColor & aColor2)

Interface Category:

API.

Purpose:

Determines the maximum of individual components of this TXYZColor and the specified color. It sets the components of this color to the resulting maximum values.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::Minimum

void Minimum (const TXYZColor & aColor2)

Interface Category:

API.

Purpose:

Determines the minimum of individual components of this TXYZColor and the specified color. It sets the components of this color to the resulting minimum values.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::Blend

void Blend (const TXYZColor & aColor2)

Interface Category:

API.

Purpose:

Averages the individual components of the two colors and returns them in this TXYZColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::Invert

void Invert ()

Interface Category:

API.

Purpose:

Inverts this TXYZColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::Clamp

void Clamp ()

Interface Category:

API.

Purpose:

Clamps the components of this TXYZColor between 0.0 <= N <= 1.0. If a value is less than 0.0, it is set to 0.0, and if it is greater than 1.0, it is set to 1.0.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::Scale

void Scale ()

Interface Category:

API.

Purpose:

Scales this TXYZColor to 1.0. If all of the color's components are between 0.0 <= N <= 1.0, the color is untouched. If there are components with values greater than 1.0, then the largest component is used to renormalize the color. If any of the color's components are less than 0.0, they set to 0.0.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TXYZColor::TemporaryTypeID

virtual TemporaryColorClassID TemporaryTypeID () const

Interface Category:

API.

Purpose:

Determines the type of color that the derived class of TXYZColor represents.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns TColor::kXYZColor.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::operator<<=

virtual TStream & operator <<= (TStream &)

Interface Category:

API.

Purpose:

Stream-in operator.

Calling Context:

Called to stream in data.

Parameters:

Return Value:

Returns a reference to the stream the object streams itself in from.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::operator>>=

virtual TStream & operator >>=(TStream &) const

Interface Category:

API.

Purpose:

Stream-out operator.

Calling Context:

Called to stream out data.

Parameters:

Return Value:

Returns a reference to the stream the object streams itself out to.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::SetX

void SetX (TristimulusCoord aX)

Interface Category:

API.

Purpose:

Sets the X component of this TXYZColor to the specified value.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::~TXYZColor

virtual ~ TXYZColor ()

Interface Category:

API.

Purpose:

Destructor.

Calling Context:

Called to destroy an object.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::ClampOpacity

void ClampOpacity ()

Interface Category:

API.

Purpose:

Pins the opacity of this TXYZColor to the range 0.0 to 1.0.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::SetOpacity

void SetOpacity (GIntensity opacity =1.0)

Interface Category:

API.

Purpose:

Sets the opacity of this TXYZColor to the specified value.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::GetClampedOpacity

GIntensity GetClampedOpacity () const

Interface Category:

API.

Purpose:

Returns the opacity of this TXYZColor and pins the value to the range 0.0 to 1.0.

Calling Context:

Call this function directly.

Parameters:

Return Value:

The clamped opacity.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TXYZColor::GetOpacity

GIntensity GetOpacity () const

Interface Category:

API.

Purpose:

Returns the opacity of this TXYZColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

The opacity that can be outside the range 0.0 to 1.0.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.
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