KasmVNC/common/rfb/Decoder.h
2020-09-20 12:16:44 +00:00

98 lines
3.6 KiB
C++

/* Copyright (C) 2002-2005 RealVNC Ltd. All Rights Reserved.
* Copyright 2014 Pierre Ossman for Cendio AB
*
* This 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 software 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.
*
* You should have received a copy of the GNU General Public License
* along with this software; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
* USA.
*/
#ifndef __RFB_DECODER_H__
#define __RFB_DECODER_H__
namespace rdr {
class InStream;
class OutStream;
}
namespace rfb {
class ConnParams;
class ModifiablePixelBuffer;
class Region;
struct Rect;
enum DecoderFlags {
// A constant for decoders that don't need anything special
DecoderPlain = 0,
// All rects for this decoder must be handled in order
DecoderOrdered = 1 << 0,
// Only some of the rects must be handled in order,
// see doesRectsConflict()
DecoderPartiallyOrdered = 1 << 1,
};
class Decoder {
public:
Decoder(enum DecoderFlags flags);
virtual ~Decoder();
// These functions are the main interface to an individual decoder
// readRect() transfers data for the given rectangle from the
// InStream to the OutStream, possibly changing it along the way to
// make it easier to decode. This function will always be called in
// a serial manner on the main thread.
virtual void readRect(const Rect& r, rdr::InStream* is,
const ConnParams& cp, rdr::OutStream* os)=0;
// These functions will be called from any of the worker threads.
// A lock will be held whilst these are called so it is safe to
// read and update internal state as necessary.
// getAffectedRegion() returns the parts of the frame buffer will
// be either read from or written do when decoding this rect. The
// default implementation simply returns the given rectangle.
virtual void getAffectedRegion(const Rect& rect, const void* buffer,
size_t buflen, const ConnParams& cp,
Region* region);
// doesRectsConflict() determines if two rectangles must be decoded
// in the order they were received. This will only be called if the
// DecoderPartiallyOrdered flag has been set.
virtual bool doRectsConflict(const Rect& rectA,
const void* bufferA,
size_t buflenA,
const Rect& rectB,
const void* bufferB,
size_t buflenB,
const ConnParams& cp);
// decodeRect() decodes the given rectangle with data from the
// given buffer, onto the ModifiablePixelBuffer. The PixelFormat of
// the PixelBuffer might not match the ConnParams and it is up to
// the decoder to do any necessary conversion.
virtual void decodeRect(const Rect& r, const void* buffer,
size_t buflen, const ConnParams& cp,
ModifiablePixelBuffer* pb)=0;
public:
static bool supported(int encoding);
static Decoder* createDecoder(int encoding);
public:
const enum DecoderFlags flags;
};
}
#endif