IlvColor Class Reference

Resource class. More...

#include <ilviews/base/resource.h>

Inheritance diagram for IlvColor:

List of all members.

Public Member Functions
IlvIntensity	getBlue () const
	Retrieves the blue component value.
IlvIntensity	getGreen () const
	Retrieves the green component value.
void	getHSV (IlFloat &hue, IlFloat &saturation, IlFloat &value) const
	Retrieves the HSV values.
IlFloat	getHue () const
	Retrieves the hue value.
IlUInt	getIndex () const
	Gets the index of this color.
IlvIntensity	getRed () const
	Retrieves the red component value.
void	getRGB (IlvIntensity &red, IlvIntensity &green, IlvIntensity &blue) const
	Retrieves the RGB component values.
IlFloat	getSaturation () const
	Retrieves the color saturation value.
IlFloat	getValue () const
	Retrieves the luminosity value.
IlBoolean	isMutable () const
	Get the mutable attribute.
void	setBlue (IlvIntensity blue)
	Sets the blue component value.
void	setGreen (IlvIntensity green)
	Sets the green component value.
void	setHSV (IlFloat hue, IlFloat saturation, IlFloat value)
	Sets the HSV parameters.
void	setHue (IlFloat hue)
	Sets the hue value.
virtual void	setName (const char *name)
	Sets the name of the resource.
void	setRed (IlvIntensity red)
	Sets the red component value.
void	setRGB (IlvIntensity red, IlvIntensity green, IlvIntensity blue)
	Sets the RGB component values.
void	setSaturation (IlFloat saturation)
	Sets the saturation.
void	setValue (IlFloat value)
	Sets the luminosity value.
virtual void	unLock ()
	Unlocks the resource.
Static Public Member Functions
static void	ComputeReliefColors (const IlvColor *reference, IlvColor *&topShade, IlvColor *&bottomShade, IlvColor *&select)
	Computes colors that make a shadow effect.
static void	HSVToRGB (IlFloat h, IlFloat s, IlFloat v, IlvIntensity &red, IlvIntensity &green, IlvIntensity &blue)
	Converts HSV values to the RGB model.
static void	RGBToHSV (IlvIntensity red, IlvIntensity green, IlvIntensity blue, IlFloat &h, IlFloat &s, IlFloat &v)
	Converts RGB values to the HSV model.
Friends
class	IlvDisplay

---

Detailed Description

Resource class.

Library: display

This class lets you manipulate color objects, both in the RGB and the HSV color models.

IlvColor has no constructor. The only way to obtain a color is to ask your IlvDisplay object to get it for you.

A color is entirely defined by its three component values: red, green and blue. These values are stored as unsigned 16-bit numbers. For example, black is defined with its three components set to zero, and white has its three components set to 65535.

An IlvColor can be mutable on systems that accept it. Values defining a mutable color can be modified on the fly, allowing to animate your displays without requiring a refresh of the screen.

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Member Function Documentation

static void IlvColor::ComputeReliefColors	(	const IlvColor *	reference,
		IlvColor *&	topShade,
		IlvColor *&	bottomShade,
		IlvColor *&	select
	)			[static]

Computes colors that make a shadow effect.

The different colors are derived from reference by making it brighter or dimmer.

Parameters:

	reference	The reference color.
	topShade	Is set to a brighter version of reference.
	bottomShade	Is set to a dimmer version of reference.
	select	A color that looks like a selected version of reference (usually slightly dimmer).

IlvIntensity IlvColor::getBlue

(

)

const

Retrieves the blue component value.

Returns:

The intensity of the blue component.

IlvIntensity IlvColor::getGreen

(

)

const

Retrieves the green component value.

Returns:

The intensity of the green component.

void IlvColor::getHSV	(	IlFloat &	hue,
		IlFloat &	saturation,
		IlFloat &	value
	)			const

Retrieves the HSV values.

Obtains the current values of all three HSV components: hue, saturation and luminosity.

Parameters:

	hue	The hue value of this color.
	saturation	The saturation value of this color.
	value	The luminosity value of this color.

IlFloat IlvColor::getHue

(

)

const

Retrieves the hue value.

This value is computed from the RGB color model. It corresponds to an angle in the HSV color model, where a value of 0 indicates a pure red color, 120 indicates a pure blue color, and 240 indicates a pure green color.

Returns:

The hue of the current color. In the context of the HSV cone model, this number represents an angle in the range of 0 to 360 degrees.

IlUInt IlvColor::getIndex

(

)

const

Gets the index of this color.

Colors are generally stored in a color table that is maintained internally by your IlvDisplay object. You can obtain the index of a color object (an unsigned long integer) by means of this member function. Then you can use this number for remapping processes involving color bitmaps, when you want to map pixel values to color objects.

Returns:

The index of this color in the color map. If the display where this color was allocated has true-color capabilities, the returned value is the entire 24-bit color representation.

IlvIntensity IlvColor::getRed

(

)

const

Retrieves the red component value.

Returns:

The intensity of the red component.

void IlvColor::getRGB	(	IlvIntensity &	red,
		IlvIntensity &	green,
		IlvIntensity &	blue
	)			const

Retrieves the RGB component values.

Parameters:

	red	The red component value.
	green	The green component value.
	blue	The blue component value.

IlFloat IlvColor::getSaturation

(

)

const

Retrieves the color saturation value.

Returns:

The saturation of the current color. In the context of the HSV cone model, this number ranges from zero (gray) to one (maximum vividness).

IlFloat IlvColor::getValue

(

)

const

Retrieves the luminosity value.

Returns:

The luminosity of the current color. In the context of the HSV cone model, this number ranges from zero (black) to one (white).

static void IlvColor::HSVToRGB	(	IlFloat	h,
		IlFloat	s,
		IlFloat	v,
		IlvIntensity &	red,
		IlvIntensity &	green,
		IlvIntensity &	blue
	)			[static]

Converts HSV values to the RGB model.

Parameters:

	h	The input hue value.
	s	The input saturation value.
	v	The input luminosity value. If this is 0 the output result will always be 0 for all components, no matter what values are set in h and s.
	red	Is set to the output red component value.
	green	Is set to the output green component value.
	blue	Is set to the output blue component value.

IlBoolean IlvColor::isMutable

(

)

const

Get the mutable attribute.

Returns:

A Boolean value that indicates whether this color is mutable or not. A color can be either static (impossible to modify after its creation) or mutable. In the latter case, you can use set member functions to dynamically modify a color, even when there are drawings with this color on the screen. (These set functions are indicated in the next functions.)

Mutable colors are costly, however, in terms of internal resource management. You specify whether or not you want mutable color in the IlvDisplay member functions that create these objects.

static void IlvColor::RGBToHSV	(	IlvIntensity	red,
		IlvIntensity	green,
		IlvIntensity	blue,
		IlFloat &	h,
		IlFloat &	s,
		IlFloat &	v
	)			[static]

Converts RGB values to the HSV model.

Parameters:

	red	The input red value.
	green	The input green value.
	blue	The input blue value.
	h	Is set to the output hue value.
	s	Is set to the output saturation value.
	v	Is set to the output luminosity value value.

void IlvColor::setBlue

(

IlvIntensity

blue

)

Sets the blue component value.

This member function does nothing if this color is not mutable.

Assigns an intensity to the blue component. If the mutable color is allocated in a higher bitPlaneGroup (that is, the allocated color allocates many slots of the color map) then all the slots are modified.

Parameters:

blue

The new blue component value of this color.

void IlvColor::setGreen

(

IlvIntensity

green

)

Sets the green component value.

This member function does nothing if this color is not mutable.

Assigns an intensity to the green component. If the mutable color is allocated in a higher bitPlaneGroup (that is, the allocated color allocates many slots of the color map) then all the slots are modified.

Parameters:

green

The new green component value of this color.

void IlvColor::setHSV	(	IlFloat	hue,
		IlFloat	saturation,
		IlFloat	value
	)

Sets the HSV parameters.

This member function does nothing if this color is not mutable.

Assigns values to all three HSV components: hue, saturation and luminosity.

Parameters:

	hue	The new hue value of this color.
	saturation	The new saturation value of this color.
	value	The new luminosity value of this color.

void IlvColor::setHue

(

IlFloat

hue

)

Sets the hue value.

This member function does nothing if this color is not mutable.

Assigns a hue value to the current color. In the context of the HSV cone model, this number represents an angle in the range of 0 to 360º.

Parameters:

hue

The new hue value of this color.

virtual void IlvColor::setName

(

const char *

name

)

[virtual]

Sets the name of the resource.

Names your resource by means of a unique name string descriptor that is internally copied.

Reimplemented from IlvResource.

void IlvColor::setRed

(

IlvIntensity

red

)

Sets the red component value.

This member function does nothing if this color is not mutable.

Assigns an intensity to the red component. If the mutable color is allocated in a higher bitPlaneGroup (that is, the allocated color allocates many slots of the color map) then all the slots are modified.

Parameters:

red

The new red component value of this color.

void IlvColor::setRGB	(	IlvIntensity	red,
		IlvIntensity	green,
		IlvIntensity	blue
	)

Sets the RGB component values.

This member function does nothing if this color is not mutable.

Assigns intensities to all three components: red, green and blue. If the mutable color is allocated in a higher bitPlaneGroup (that is, the allocated color allocates many slots of the color map) then all the components are modified.

Parameters:

	red	The new red component value of this color.
	green	The new green component value of this color.
	blue	The new blue component value of this color.

void IlvColor::setSaturation

(

IlFloat

saturation

)

Sets the saturation.

This member function does nothing if this color is not mutable.

Assigns a saturation value to the current color. In the context of the HSV cone model, this number ranges from zero (gray) to one (maximum vividness).

Parameters:

saturation

The new saturation value of this color.

void IlvColor::setValue

(

IlFloat

value

)

Sets the luminosity value.

This member function does nothing if this color is not mutable.

Assigns a luminosity value to the current color. In the context of the HSV cone model, this number ranges from zero (black) to one (white).

Parameters:

value

The new luminosity value of this color.

virtual void IlvColor::unLock

(

)

[virtual]

Unlocks the resource.

This function decrements the reference count of the resource, and deletes it if this count becomes 0. Resource management is closely concerned with the way resources are locked and unlocked. Whenever you need a specific resource in one of your persistent objects, you should use this mechanism to make sure that it will stay safe within your IlvDisplay instance. If your application needs more than one instance of IlvDisplay, you have to create resources within each environment, since resources cannot be shared between the different IlvDisplay contexts.

Reimplemented from IlvResource.