// $Id: PostProcessor.hh 6137 2007-03-03 14:03:31Z m9710797 $

#ifndef POSTPROCESSOR_HH
#define POSTPROCESSOR_HH

#include "FrameSource.hh"
#include "VideoLayer.hh"
#include "EmuTime.hh"

namespace openmsx {

class CommandController;
class Display;
class RenderSettings;
class VisibleSurface;
class RawFrame;
class DeinterlacedFrame;
class DoubledFrame;
class AviRecorder;

/** Abstract base class for post processors.
  * A post processor builds the frame that is displayed from the MSX frame,
  * while applying effects such as scalers, noise etc.
  * TODO: With some refactoring, it would be possible to move much or even all
  *       of the post processing code here instead of in the subclasses.
  */
class PostProcessor : public VideoLayer
{
public:
	virtual ~PostProcessor();

	// Layer interface:
	virtual void paint() = 0;
	virtual const std::string& getName();

	/** Sets up the "abcdFrame" variables for a new frame.
	  * TODO: The point of passing the finished frame in and the new workFrame
	  *       out is to be able to split off the scaler application as a
	  *       separate class.
	  * @param finishedFrame Frame that has just become available.
	  * @param field Specifies what role (if any) the new frame plays in
	  *   interlacing.
	  * @param time The moment in time the frame becomes available. Used to
	  *             calculate the framerate for recording (depends on
	  *             PAL/NTSC, frameskip).
	  * @return RawFrame object that can be used for building the next frame.
	  */
	virtual RawFrame* rotateFrames(
		RawFrame* finishedFrame, FrameSource::FieldType field,
		const EmuTime& time);

	/** Start/stop recording.
	  * @param recorder Finished frames should be pushed to this
	  *                 AviRecorder. Can also be a NULL pointer, meaning
	  *                 recording is stopped.
	  */
	void setRecorder(AviRecorder* recorder);

	/** Is recording active.
	  * ATM used to keep frameskip constant during recording.
	  */
	bool isRecording() const;

	/** Get the number of bits per pixel for the pixels in these frames.
	  * @return Possible values are 15, 16 or 32
	  */
	unsigned getBpp() const;

protected:
	/** Returns the maximum width for lines [y..y+step).
	  */
	static unsigned getLineWidth(FrameSource* frame, unsigned y, unsigned step);

	PostProcessor(
		CommandController& commandController, Display& display,
		VisibleSurface& screen, VideoSource videoSource,
		unsigned maxWidth, unsigned height);

	/** Render settings */
	RenderSettings& renderSettings;

	/** The surface which is visible to the user. */
	VisibleSurface& screen;

	/** The last finished frame, ready to be displayed. */
	RawFrame* currFrame;

	/** The frame before currFrame, ready to be displayed. */
	RawFrame* prevFrame;

	/** Combined currFrame and prevFrame. */
	DeinterlacedFrame* deinterlacedFrame;

	/** Each line of currFrame twice, to get double vertical resolution. */
	DoubledFrame* interlacedFrame;
	
	/** Represents a frame as it should be displayed.
	  * This can be simply a RawFrame or two RawFrames combined in a
	  * DeinterlacedFrame or DoubledFrame.
	  */
	FrameSource* paintFrame;

	/** Video recorder, NULL when not recording. */
	AviRecorder* recorder;

	/** Time when rotateFrames() was last called. */
	EmuTime prevTime;

private:
	CommandController& commandController;
};

} // namespace openmsx

#endif // POSTPROCESSOR_HH