Class: Clutter::OffscreenEffect

Inherits:

Effect

• Object
• GObject::InitiallyUnowned
• ActorMeta
• Effect
• Clutter::OffscreenEffect

Defined in:

(unknown)

Overview

The Clutter::OffscreenEffectClass structure contains only private data

Direct Known Subclasses

BlurEffect, BrightnessContrastEffect, ColorizeEffect, DeformEffect, DesaturateEffect, ShaderEffect

Instance Method Summary

• #create_texture(width, height) ⇒ Cogl::Handle

  Calls the create_texture() virtual function of the effect.

• #get_target_rect(rect) ⇒ Boolean

  Retrieves the origin and size of the offscreen buffer used by effect to paint the actor to which it has been applied.

• #get_target_size(width, height) ⇒ Boolean

  Retrieves the size of the offscreen buffer used by effect to paint the actor to which it has been applied.

• #paint_target ⇒ nil

  Calls the paint_target() virtual function of the effect.

• #target ⇒ Cogl::Material

  Retrieves the material used as a render target for the offscreen buffer created by effect.

• #texture ⇒ Cogl::Handle

  Retrieves the texture used as a render target for the offscreen buffer created by effect.

Methods inherited from Effect

#queue_repaint

Methods inherited from ActorMeta

#actor, #actor=, #enabled, #enabled=, #enabled?, #name, #name=

Instance Method Details

#create_texture(width, height) ⇒ Cogl::Handle

Calls the create_texture() virtual function of the effect

Parameters:

• width (Clutter::gfloat) —

  the minimum width of the target texture

• height (Clutter::gfloat) —

  the minimum height of the target texture

Returns:

• (Cogl::Handle) —

  a handle to a Cogl texture, or
  %COGL_INVALID_HANDLE. The returned handle has its reference
  count increased.

#get_target_rect(rect) ⇒ Boolean

Retrieves the origin and size of the offscreen buffer used by effect to
paint the actor to which it has been applied.

This function should only be called by Clutter::OffscreenEffect
implementations, from within the Clutter::OffscreenEffectClass.paint_target()
virtual function.

Parameters:

• rect (Clutter::Rect) —

  return location for the target area

Returns:

• (Boolean) —

  true if the offscreen buffer has a valid rectangle,
  and false otherwise

#get_target_size(width, height) ⇒ Boolean

Retrieves the size of the offscreen buffer used by effect to
paint the actor to which it has been applied.

This function should only be called by Clutter::OffscreenEffect
implementations, from within the Clutter::OffscreenEffectClass.paint_target()
virtual function.

Parameters:

• width (Clutter::gfloat) —

  return location for the target width, or nil

• height (Clutter::gfloat) —

  return location for the target height, or nil

Returns:

• (Boolean) —

  true if the offscreen buffer has a valid size,
  and false otherwise

#paint_target ⇒ nil

Calls the paint_target() virtual function of the effect

Returns:

• (nil)

#target ⇒ Cogl::Material

Retrieves the material used as a render target for the offscreen
buffer created by effect

You should only use the returned Cogl::Material when painting. The
returned material might change between different frames.

Returns:

• (Cogl::Material) —

  a Cogl::Material or nil. The
  returned material is owned by Clutter and it should not be
  modified or freed

#texture ⇒ Cogl::Handle

Retrieves the texture used as a render target for the offscreen
buffer created by effect

You should only use the returned texture when painting. The texture
may change after ClutterEffect::pre_paint is called so the effect
implementation should update any references to the texture after
chaining-up to the parent's pre_paint implementation. This can be
used instead of clutter_offscreen_effect_get_target() when the
effect subclass wants to paint using its own material.

Returns:

• (Cogl::Handle) —

  a Cogl::Handle or %COGL_INVALID_HANDLE. The
  returned texture is owned by Clutter and it should not be
  modified or freed