Taxonomy Categories:
Member Functions:
Interface Category:
API.
Inherits From:
TColor
Inherited By:
None.
Purpose:
The National Television System Committee (NTSC) in 1952 defined the color television system which is used in North America and Japan. In doing so, they also defined the CIE xy chromaticity coordinates of the display phosphors as:
Phosphors x y z
Red 0.67 0.33 0.00
Green 0.21 0.71 0.08
Blue 0.14 0.08 0.78
The Y is defined as luminance and is exactly the same as the Y in the XYZ color space. It is also the same as the black and white signals on a TV. Two chromaticities, represented by I and Q, are used to transmit color information.
The class provides arithmetic operators that operate on two colors.
Instantiation:
Allocate on the heap or the stack.
Deriving Classes:
Derive new color models from TColor.
Concurrency:
Multithread safe.
Resource Use:
No special requirements.
- TYIQColor ()
- TYIQColor (const TColor & aColor)
- TYIQColor (TColorProfile * theDeviceColorProfile)
- TYIQColor (GIntensity aY, GIntensity aI, GIntensity aQ, GIntensity opacity =1.0)
- TYIQColor (const TYIQColor & aYIQColor)
- TYIQColor (TColorProfile * theDeviceColorProfile, GIntensity aY, GIntensity aI, GIntensity aQ, GIntensity opacity =1.0)
Interface Category:
API.
Purpose:
- Default constructor; it has the default color profile, and color components are not initialized.
- Creates a TYIQColor from a TColor.
- Creates a TYIQColor with the specified color profile. The color components are not initialized.
- Creates a TYIQColor with the specified components. It has the default color profile.
- Copy constructor.
- Creates a TYIQColor with the specified components and color profile.
Calling Context:
- Called by the stream-in operators. You can also call this function directly.
- Call this function directly.
- Call this function directly.
- Call this function directly.
- Called to copy an object. You can also call this function directly.
- Call this function directly.
Parameters:
- Takes no parameters.
- const TColor & aColor -The color to be copied.
- TColorProfile * theDeviceColorProfile -The color profile for the new color.
- GIntensity aY -The Y component of the new color.
- GIntensity aI -The I component of the new color.
- GIntensity aQ -The Q component of the new color.
- GIntensity opacity =1.0 -The opacity of the new color.
- const TYIQColor & aYIQColor -The color to be copied.
- TColorProfile * theDeviceColorProfile -The color profile for the new color.
- GIntensity aY -The Y component of the new color.
- GIntensity aI -The I component of the new color.
- GIntensity aQ -The Q component of the new color.
- GIntensity opacity =1.0 -The opacity of the new color.
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Member Function: TYIQColor::GetComponents
void GetComponents (GIntensity & aY, GIntensity & aI, GIntensity & aQ, GIntensity & opacity) const
Interface Category:
API.
Purpose:
Gets the components of this TCMYKColor.
Calling Context:
Call this function directly.
Parameters:
- GIntensity & aY -The Y component of the color.
- GIntensity & aI -The I component of the color.
- GIntensity & aQ -The Q component of the color.
- GIntensity & opacity -The opacity of the color.
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
Member Function: TYIQColor::GetClampedComponents
void GetClampedComponents (GIntensity & aY, GIntensity & aI, GIntensity & aQ, GIntensity & opacity) const
Interface Category:
API.
Purpose:
Gets the components of this TYIQColor clamped between 0.0 <= N <=1.0.
Calling Context:
Call this function directly.
Parameters:
- GIntensity & aY -The clamped Y component of this color.
- GIntensity & aI -The clamped I component of this color.
- GIntensity & aQ -The clamped Q component of this color.
- GIntensity & opacity -The clamped opacity of this color.
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
Member Function: TYIQColor::GetY
GIntensity GetY () const
Interface Category:
API.
Purpose:
Gets the Y component of this TYIQColor.
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: TYIQColor::GetI
GIntensity GetI () const
Interface Category:
API.
Purpose:
Gets the I component of this TYIQColor.
Calling Context:
Call this function directly.
Parameters:
Return Value:
Returns the I component of the color.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
Member Function: TYIQColor::GetQ
GIntensity GetQ () const
Interface Category:
API.
Purpose:
Gets the Q component of this TYIQColor.
Calling Context:
Call this function directly.
Parameters:
Return Value:
Returns the Q component of the color.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
Member Function: TYIQColor::GetColorDifference
GCoordinate GetColorDifference (const TYIQColor & aColor2) const
Interface Category:
API.
Purpose:
Calculates the color difference between this TYIQColor and the specified one. The color difference is defined as the sqrt( (Y1-Y2)^2+(I1-I2)^2+(Q1-Q2)^2 ).
Calling Context:
Call this function directly.
Parameters:
- const TYIQColor & aColor2 -The color with which the difference is computed.
Return Value:
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: TYIQColor::SetComponents
void SetComponents (GIntensity aY, GIntensity aI, GIntensity aQ, GIntensity opacity =1.0)
Interface Category:
API.
Purpose:
Sets the components of this TYIQColor to the specified values.
Calling Context:
Call this function directly.
Parameters:
- GIntensity aY -The new value for the Y component.
- GIntensity aI -The new value for the I component.
- GIntensity aQ -The new value for the Q component.
- GIntensity opacity =1.0 -The new value for the opacity.
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
Member Function: TYIQColor::SetI
void SetI (GIntensity aI)
Interface Category:
API.
Purpose:
Sets the I component of this TYIQColor.
Calling Context:
Call this function directly.
Parameters:
- GIntensity aI -The new value for the I component.
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
Member Function: TYIQColor::SetQ
void SetQ (GIntensity aQ)
Interface Category:
API.
Purpose:
Sets the Q component of this TYIQColor.
Calling Context:
Call this function directly.
Parameters:
- GIntensity aQ -The new value for the Q component.
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
Member Function: TYIQColor::operatorTRGBColor
virtual operator TRGBColor () const
Interface Category:
API.
Purpose:
Casts this TYIQColor to a TRGBColor.
Calling Context:
Call this operator directly.
Parameters:
Return Value:
Returns an RGBColor that corresponds to this color.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
Member Function: TYIQColor::operatorTXYZColor
virtual operator TXYZColor () const
Interface Category:
API.
Purpose:
Casts this TYIQColor to a TXYZColor.
Calling Context:
Call this operator directly.
Parameters:
Return Value:
Returns an XYZColor that corresponds to this color.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
Member Function: TYIQColor::operator=
- TYIQColor & operator =(const TYIQColor & aSource)
- TColor & operator =(const TColor & aSource)
Interface Category:
API.
Purpose:
- Assignment operator.
- Assignment operator that casts the specified operand to a TYIQColor.
Calling Context:
- Called when an object is assigned to another compatible object.
- Called when an object is assigned to another compatible object.
Parameters:
- const TYIQColor & aSource -The color to be copied.
- const TColor & aSource -The color to be converted and copied.
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: TYIQColor::operator+
- TYIQColor operator + (const TYIQColor & aColor2) const
- TYIQColor operator + (const float aScalar) const
Interface Category:
API.
Purpose:
- Adds the components of the two TYIQColors together.
- Adds the specified scalar to each component of this TYIQColor.
Calling Context:
- Call this operator directly.
- Call this operator directly.
Parameters:
- const TYIQColor & aColor2 -The color to be added to this one.
- const float aScalar -The scalar to be added to each component of this color.
Return Value:
- Returns a new color with the new components.
- 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: TYIQColor::operator-
- TYIQColor operator -(const TYIQColor & aColor2) const
- TYIQColor operator -(const float aScalar) const
Interface Category:
API.
Purpose:
- Subtracts the components of the specified color from this TYIQColor.
- Subtracts the specified scalar from each component of this TYIQColor.
Calling Context:
- Call this operator directly.
- Call this operator directly.
Parameters:
- const TYIQColor & aColor2 -The subtrahend.
- const float aScalar -The subtrahend.
Return Value:
- Returns a new color with the new components.
- 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: TYIQColor::operator*
- TYIQColor operator * (const float aScalar) const
- TYIQColor operator * (const TYIQColor & aColor2) const
Interface Category:
API.
Purpose:
- Multiplies each component of this TYIQColor by the specified scalar.
- Multiplies the components of this TYIQColor by the components of the specified color.
Calling Context:
- Call this operator directly.
- Call this operator directly.
Parameters:
- const float aScalar -The multiplier.
- const TYIQColor & aColor2 -The multiplier.
Return Value:
- Returns a new color with the new components.
- 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: TYIQColor::operator/=
TYIQColor & operator /= (const float aScalar)
Interface Category:
API.
Purpose:
Divides the components of this TYIQColor by the specified scalar and assigns the new values to the respective components.
Calling Context:
Call this operator directly.
Parameters:
- const float aScalar -The divisor.
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: TYIQColor::operator+=
- TYIQColor & operator += (const float aScalar)
- TYIQColor & operator += (const TYIQColor & aColor2)
Interface Category:
API.
Purpose:
- Adds the specified scalar to the components of this TYIQColor and assigns the new values to the respective components.
- Adds the specified colors to the components of this TYIQColor and assigns the new values to the respective components.
Calling Context:
- Call this operator directly.
- Call this operator directly.
Parameters:
- const float aScalar -The number to be added to this color.
- const TYIQColor & aColor2 -The number to be added to this color.
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: TYIQColor::operator-=
- TYIQColor & operator -=(const float aScalar)
- TYIQColor & operator -=(const TYIQColor & aColor2)
Interface Category:
API.
Purpose:
- Subtracts the specified scalar from the components of this TYIQColor and assigns the new values to the respective components.
- Subtracts the specified scalar from the components of this TYIQColor and assigns the new values to the respective components.
Calling Context:
- Call this operator directly.
- Call this operator directly.
Parameters:
- const float aScalar -The subtrahend.
- const TYIQColor & aColor2 -The subtrahend.
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: TYIQColor::operator*=
TYIQColor & operator *= (const float aScalar)
Interface Category:
API.
Purpose:
Multiplies the components of this TYIQColor by the specified scalar and assigns the new values to the respective components.
Calling Context:
Call this operator directly.
Parameters:
- const float aScalar -The multiplier.
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: TYIQColor::operator/
TYIQColor operator / (const float aScalar) const
Interface Category:
API.
Purpose:
Divides each component of this TYIQColor by the specified scalar.
Calling Context:
Call this operator directly.
Parameters:
- const float aScalar -The divisor.
Return Value:
Returns this 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: TYIQColor::FuzzyCompare
- bool FuzzyCompare (const TYIQColor & aYIQColor, float acceptableErrorPerComponent =0.0001) const
- bool FuzzyCompare (const TYIQColor & aYuvColor, float errOpacity, float errY, float errI, float errQ) const
Interface Category:
API.
Purpose:
- Compares this TYIQColor 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.
- Compares this TYIQColor and the specified color to a given accuracy on a component by component level.
Calling Context:
- Call this function directly.
- Call this function directly.
Parameters:
- const TYIQColor & aYIQColor -The color that is compared to this color.
- float acceptableErrorPerComponent =0.0001 -The tolerance with which the two colors are compared.
- const TYIQColor & aYuvColor -The color that is compared to this color.
- float errOpacity -The tolerance with which the opacities of the two colors are compared.
- float errY -The tolerance with which the Y components of the two colors are compared.
- float errI -The tolerance with which the I components of the two colors are compared.
- float errQ -The tolerance with which the Q components of the two colors are compared.
Return Value:
- Returns true if the two colors are equal with reference to the specified tolerance.
- 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: TYIQColor::LinearInterpolate
void LinearInterpolate (const float aWeight, const TYIQColor & aColor2)
Interface Category:
API.
Purpose:
Makes a weighted linear interpolation of each component of this TYIQColor. The interpolation is returned in this color.
The interpolation that is done for each component is (using Y as an example) given by Y1 =Y1 + (Y2 -Y1) * Weight.
Calling Context:
Call this function directly.
Parameters:
- const float aWeight -The weight to use.
- const TYIQColor & aColor2 -The color to be interpolated with this one.
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: TYIQColor::AddAndPin
void AddAndPin (const TYIQColor & aColor2)
Interface Category:
API.
Purpose:
Adds the specified color to this TYIQColor and then clamps the resulting values of the components.
Calling Context:
Call this function directly.
Parameters:
- const TYIQColor & aColor2 -The color to be added to this one.
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: TYIQColor::SubtractAndPin
void SubtractAndPin (const TYIQColor & aColor2)
Interface Category:
API.
Purpose:
Subtracts the specified color from this TYIQColor 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: TYIQColor::Maximum
void Maximum (const TYIQColor & aColor2)
Interface Category:
API.
Purpose:
Determines the maximum of individual components of this TYIQColor and the specified color. It sets the components of this color to the resulting maximum values.
Calling Context:
Call this function directly.
Parameters:
- const TYIQColor & aColor2 -The color whose components are compared with this one.
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: TYIQColor::Minimum
void Minimum (const TYIQColor & aColor2)
Interface Category:
API.
Purpose:
Determines the minimum of individual components of this TYIQColor and the specified color. It sets the components of this color to the resulting minimum values.
Calling Context:
Call this function directly.
Parameters:
- const TYIQColor & aColor2 -The color whose components are compared with this one.
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: TYIQColor::Blend
void Blend (const TYIQColor & aColor2)
Interface Category:
API.
Purpose:
Averages the individual components of the two colors and returns them in this TYIQColor.
Calling Context:
Call this function directly.
Parameters:
- const TYIQColor & aColor2 -The color to be blended with this one.
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: TYIQColor::Invert
void Invert ()
Interface Category:
API.
Purpose:
Inverts this TYIQColor.
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: TYIQColor::Clamp
void Clamp ()
Interface Category:
API.
Purpose:
Clamps the components of this TYIQColor 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: TYIQColor::Scale
void Scale ()
Interface Category:
API.
Purpose:
Scales this TYIQColor 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 are 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: TYIQColor::TemporaryTypeID
virtual TemporaryColorClassID TemporaryTypeID () const
Interface Category:
API.
Purpose:
Returns TColor::kYIQColor.
Calling Context:
Call this function directly.
Parameters:
Return Value:
Returns TColor::kYIQColor.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
Member Function: TYIQColor::operator<<=
virtual TStream & operator <<= (TStream &)
Interface Category:
API.
Purpose:
Stream-in operator.
Calling Context:
Call this function directly.
Parameters:
- TStream & -The stream that the object's data is streamed in from.
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: TYIQColor::operator>>=
virtual TStream & operator >>=(TStream &) const
Interface Category:
API.
Purpose:
Stream-out operator.
Calling Context:
Called to stream out data.
Parameters:
- TStream & -The stream that the object's data is streamed out to.
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: TYIQColor::SetY
void SetY (GIntensity aY)
Interface Category:
API.
Purpose:
Sets the Y component of this TYIQColor.
Calling Context:
Call this function directly.
Parameters:
- GIntensity aY -The new value for the Y component.
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
virtual ~ TYIQColor ()
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: TYIQColor::ClampOpacity
void ClampOpacity ()
Interface Category:
API.
Purpose:
Pins the opacity of this TYIQColor 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: TYIQColor::SetOpacity
void SetOpacity (GIntensity opacity =1.0)
Interface Category:
API.
Purpose:
Sets the opacity of this TYIQColor to the specified value.
Calling Context:
Call this function directly.
Parameters:
- GIntensity opacity =1.0 -The new value for the opacity.
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Multithread safe.
Other Considerations:
None.
Member Function: TYIQColor::GetClampedOpacity
GIntensity GetClampedOpacity () const
Interface Category:
API.
Purpose:
Returns the opacity of this TYIQColor 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: TYIQColor::GetOpacity
GIntensity GetOpacity () const
Interface Category:
API.
Purpose:
Returns the opacity of this TYIQColor.
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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