DropShadowEffect Class Reference

An effect filter that adds a drop-shadow behind the image's content. More...

Inheritance diagram for DropShadowEffect:

Public Member Functions
	DropShadowEffect ()
	Creates a default drop-shadow effect.
	~DropShadowEffect () override
	Destructor.
void	setShadowProperties (const DropShadow &newShadow)
	Sets up parameters affecting the shadow's appearance.
void	applyEffect (Image &sourceImage, Graphics &destContext, float scaleFactor, float alpha) override
	Overridden to render the effect.
Public Member Functions inherited from ImageEffectFilter
virtual	~ImageEffectFilter ()=default
	Destructor.

Detailed Description

An effect filter that adds a drop-shadow behind the image's content.

(This will only work on images/components that aren't opaque, of course).

When added to a component, this effect will draw a soft-edged shadow based on what gets drawn inside it. The shadow will also be applied to the component's children.

For speed, this doesn't use a proper gaussian blur, but cheats by using a simple bilinear filter. If you need a really high-quality shadow, check out ImageConvolutionKernel::createGaussianBlur()

See also

Component::setComponentEffect

Constructor & Destructor Documentation

DropShadowEffect()

DropShadowEffect::DropShadowEffect

(

)

Creates a default drop-shadow effect.

To customise the shadow's appearance, use the setShadowProperties() method.

Referenced by applyEffect().

~DropShadowEffect()

DropShadowEffect::~DropShadowEffect ( )

override

Destructor.

Member Function Documentation

setShadowProperties()

void DropShadowEffect::setShadowProperties

(

const DropShadow &

newShadow

)

Sets up parameters affecting the shadow's appearance.

applyEffect()

void DropShadowEffect::applyEffect ( Image & sourceImage, Graphics & destContext, float scaleFactor, float alpha )

overridevirtual

Overridden to render the effect.

The implementation of this method must use the image that is passed in as its source, and should render its output to the graphics context passed in.

Parameters

sourceImage	the image that the source component has just rendered with its paint() method. The image may or may not have an alpha channel, depending on whether the component is opaque.
destContext	the graphics context to use to draw the resultant image.
scaleFactor	a scale factor that has been applied to the image - e.g. if this is 2, then the image is actually scaled-up to twice the original resolution
alpha	the alpha with which to draw the resultant image to the target context

Implements ImageEffectFilter.

References DropShadowEffect().