/* === S Y N F I G ========================================================= */

/*!	\file layer_composite.h

**	\brief Composite Layer Class Implementation

**

**	$Id$

**

**	\legal

**	Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley

**	Copyright (c) 2007, 2008 Chris Moore

**

**	This package is free software; you can redistribute it and/or

**	modify it under the terms of the GNU General Public License as

**	published by the Free Software Foundation; either version 2 of

**	the License, or (at your option) any later version.

**

**	This package is distributed in the hope that it will be useful,

**	but WITHOUT ANY WARRANTY; without even the implied warranty of

**	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

**	General Public License for more details.

**	\endlegal

*/

/* ========================================================================= */

/* === S T A R T =========================================================== */

#ifndef __SYNFIG_LAYER_COMPOSITE_H

#define __SYNFIG_LAYER_COMPOSITE_H

/* === H E A D E R S ======================================================= */

#include <synfig layer.h=""></synfig>

#include <synfig color.h=""></synfig>

#include <synfig cairo_operators.h=""></synfig>

/* === M A C R O S ========================================================= */

/* === T Y P E D E F S ===================================================== */

/* === C L A S S E S & S T R U C T S ======================================= */

namespace synfig {

class Layer_NoDeform {};

/*!	\class Layer_Composite

**	\brief Base class for layers that put stuff on top of lower layers

*/

class Layer_Composite : public Layer

{

private:

	//! The amount of composite

	ValueBase param_amount;

	//! The blend method for the composition

	ValueBase param_blend_method;

protected:

	//! Default constructor. Not used directly.

	explicit Layer_Composite(Real amount=1.0, Color::BlendMethod blend_method=Color::BLEND_COMPOSITE);

	//! Converted blend is used to check if an old version of canvas

	//! is used in the composition. Old Straight was used as new Composite

	//! \todo verify this

	bool converted_blend_;

	//! Transparent color is used for old canvas versions.

	//!Old Straight plus transparent color seems to be the same new than alpha over.

	bool transparent_color_;

public:

	//! Gets the amount of the layer

	float get_amount()const { return param_amount.get(Real()); }

	//! Sets the amount of the layer and returns this layer

	Layer_Composite& set_amount(float x) { param_amount.set(x); return *this; }

	//! Gets the blend method of the layer

	Color::BlendMethod get_blend_method()const { return Color::BlendMethod((param_blend_method.get(int()))); }

	//! Sets the blend method of the layer and returns this layer

	Layer_Composite& set_blend_method(Color::BlendMethod x) { param_blend_method.set(int(x)); return *this; }

	//! Returns true is amount is 1 and blend method is straight

	virtual bool is_solid_color()const { return param_amount.get(Real())==1.0f && param_blend_method.get(int())==Color::BLEND_STRAIGHT; }

	//! Returns true if the amount is zero.

	bool is_disabled()const { return param_amount.get(Real())==0.0f; }

	//! Gets the parameter vocabulary. To be overridden by the derived.

	virtual Vocab get_param_vocab()const;

	//! Sets the value for the given parameter.

	virtual bool set_param(const String ¶m, const ValueBase &value);

	//! Gets the value of the given parameter

	virtual ValueBase get_param(const String ¶m)const;

	//!Returns the rectangle that includes the context of the layer and

	//! the intersection of the layer in case it is active and not onto

	virtual Rect get_full_bounding_rect(Context context)const;

protected:

	virtual rendering::Task::Handle build_composite_task_vfunc(ContextParams context_params)const;

	virtual rendering::Task::Handle build_rendering_task_vfunc(Context context)const;

}; // END of class Layer_Composite

}; // END of namespace synfig

/* === E N D =============================================================== */

#endif