com.itextpdf.kernel.colors.gradients

Class LinearGradientBuilder

java.lang.Object

com.itextpdf.kernel.colors.gradients.AbstractLinearGradientBuilder

com.itextpdf.kernel.colors.gradients.LinearGradientBuilder

public class LinearGradientBuilder
extends AbstractLinearGradientBuilder

The linear gradient builder implementation with direct target gradient vector and shading transformation (more info)

Field Summary

Fields inherited from class com.itextpdf.kernel.colors.gradients.AbstractLinearGradientBuilder

ZERO_EPSILON

Constructor Summary

Constructors

Constructor and Description
LinearGradientBuilder() Constructs the builder instance

Method Summary

Modifier and Type	Method and Description
AffineTransform	getCurrentSpaceToGradientVectorSpaceTransformation(Rectangle targetBoundingBox, AffineTransform contextTransform) Returns the current space to gradient vector space transformations that should be applied to the shading color.
Point[]	getGradientVector(Rectangle targetBoundingBox, AffineTransform contextTransform) Returns the base gradient vector in gradient vector space.
LinearGradientBuilder	setCurrentSpaceToGradientVectorSpaceTransformation(AffineTransform transformation) Set the linear gradient space transformation which specifies the transformation from the current coordinates space to gradient vector space
LinearGradientBuilder	setGradientVector(double x0, double y0, double x1, double y1) Set coordinates for gradient vector (more info)

Methods inherited from class com.itextpdf.kernel.colors.gradients.AbstractLinearGradientBuilder

addColorStop, buildColor, createCoordinatesForNewDomain, evaluateCoveringDomain, getColorStops, getSpreadMethod, setSpreadMethod

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

LinearGradientBuilder

public LinearGradientBuilder()

Constructs the builder instance

Method Detail

setGradientVector

public LinearGradientBuilder setGradientVector(double x0,
                                               double y0,
                                               double x1,
                                               double y1)

Set coordinates for gradient vector (more info)

Parameters:

x0 - the x coordinate of the vector start

y0 - the y coordinate of the vector start

x1 - the x coordinate of the vector end

y1 - the y coordinate of the vector end

Returns:

the current builder instance

setCurrentSpaceToGradientVectorSpaceTransformation

public LinearGradientBuilder setCurrentSpaceToGradientVectorSpaceTransformation(AffineTransform transformation)

Set the linear gradient space transformation which specifies the transformation from the current coordinates space to gradient vector space

The current space is the one on which linear gradient will be drawn (as a fill or stroke color for shapes on PDF canvas). This transformation mainly used for color lines skewing.

Parameters:

transformation - the AffineTransform representing the transformation to set

Returns:

the current builder instance

getGradientVector

public Point[] getGradientVector(Rectangle targetBoundingBox,
                                 AffineTransform contextTransform)

Description copied from class: AbstractLinearGradientBuilder

Returns the base gradient vector in gradient vector space. This vector would be set as shading coordinates vector and its length would be used to translate all color stops absolute offsets into the relatives.

Specified by:

getGradientVector in class AbstractLinearGradientBuilder

Parameters:

targetBoundingBox - the rectangle to be covered by constructed color in current space

contextTransform - the current canvas transformation

Returns:

the array of exactly two elements specifying the gradient coordinates vector

getCurrentSpaceToGradientVectorSpaceTransformation

public AffineTransform getCurrentSpaceToGradientVectorSpaceTransformation(Rectangle targetBoundingBox,
                                                                          AffineTransform contextTransform)

Description copied from class: AbstractLinearGradientBuilder

Returns the current space to gradient vector space transformations that should be applied to the shading color. The transformation should be invertible as the current target bounding box coordinates should be transformed into the resulted shading space coordinates.

Overrides:

getCurrentSpaceToGradientVectorSpaceTransformation in class AbstractLinearGradientBuilder

Parameters:

targetBoundingBox - the rectangle to be covered by constructed color in current space

contextTransform - the current canvas transformation

Returns:

the additional transformation to be concatenated to the current for resulted shading or null if no additional transformation is specified