engines/gig/Stream.cpp

/***************************************************************************
 *                                                                         *
 *   LinuxSampler - modular, streaming capable sampler                     *
 *                                                                         *
 *   Copyright (C) 2003 by Benno Senoner                                   *
 *                                                                         *
 *   This program 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 program 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 program; if not, write to the Free Software           *
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston,                 *
 *   MA  02111-1307  USA                                                   *
 ***************************************************************************/

#include "Stream.h"

namespace LinuxSampler { namespace gig {

    uint Stream::UnusedStreams = 0;

    /// Returns number of refilled sample points or a value < 0 on error.
    int Stream::ReadAhead(unsigned long SampleCount) {
        if (this->State == state_unused) return -1;
        if (this->State == state_end)    return  0;
        if (!SampleCount)                return  0;
        if (!pRingBuffer->write_space()) return  0;

        long total_readsamples = 0, readsamples = 0;
        long samplestoread = SampleCount / pSample->Channels;
        sample_t* pBuf = pRingBuffer->get_write_ptr();
        bool endofsamplereached;

        // refill the disk stream buffer
        if (this->DoLoop) { // honor looping
            total_readsamples  = pSample->ReadAndLoop(pBuf, samplestoread, &this->PlaybackState);
            endofsamplereached = (this->PlaybackState.position >= pSample->SamplesTotal);
            dmsg(5,("Refilled stream %d with %d (SamplePos: %d)", this->hThis, total_readsamples, this->PlaybackState.position));
        }
        else { // normal forward playback

            pSample->SetPos(this->SampleOffset); // recover old position

            do {
                readsamples        = pSample->Read(&pBuf[total_readsamples * pSample->Channels], samplestoread);
                samplestoread     -= readsamples;
                total_readsamples += readsamples;
            } while (samplestoread && readsamples > 0);

            // we have to store the position within the sample, because other streams might use the same sample
            this->SampleOffset = pSample->GetPos();

            endofsamplereached = (SampleOffset >= pSample->SamplesTotal);
            dmsg(5,("Refilled stream %d with %d (SamplePos: %d)", this->hThis, total_readsamples, this->SampleOffset));
        }

        // we must delay the increment_write_ptr_with_wrap() after the while() loop because we need to
        // ensure that we read exactly SampleCount sample, otherwise the buffer wrapping code will fail
        pRingBuffer->increment_write_ptr_with_wrap(total_readsamples * pSample->Channels);

        // update stream state
        if (endofsamplereached) SetState(state_end);
        else                    SetState(state_active);

        return total_readsamples;
    }

    void Stream::WriteSilence(unsigned long SilenceSampleWords) {
        memset(pRingBuffer->get_write_ptr(), 0, SilenceSampleWords);
        pRingBuffer->increment_write_ptr_with_wrap(SilenceSampleWords);
    }

    Stream::Stream(uint BufferSize, uint BufferWrapElements) {
        this->pExportReference               = NULL;
        this->State                          = state_unused;
        this->hThis                          = 0;
        this->pSample                        = NULL;
        this->SampleOffset                   = 0;
        this->PlaybackState.position         = 0;
        this->PlaybackState.reverse          = false;
        this->pRingBuffer                    = new RingBuffer<sample_t>(BufferSize, BufferWrapElements);
        UnusedStreams++;
    }

    Stream::~Stream() {
        Reset();
        if (pRingBuffer) delete pRingBuffer;
    }

    /// Called by disk thread to activate the disk stream.
    void Stream::Launch(Stream::Handle hStream, reference_t* pExportReference, ::gig::Sample* pSample, unsigned long SampleOffset, bool DoLoop) {
        UnusedStreams--;
        this->pExportReference               = pExportReference;
        this->hThis                          = hStream;
        this->pSample                        = pSample;
        this->SampleOffset                   = SampleOffset;
        this->PlaybackState.position         = SampleOffset;
        this->PlaybackState.reverse          = false;
        this->PlaybackState.loop_cycles_left = pSample->LoopPlayCount;
        this->DoLoop                         = DoLoop;
        SetState(state_active);
    }

}} // namespace LinuxSampler::gig
1	schoenebeck	53	/***************************************************************************
2			* *
3			* LinuxSampler - modular, streaming capable sampler *
4			* *
5			* Copyright (C) 2003 by Benno Senoner *
6			* *
7			* This program is free software; you can redistribute it and/or modify *
8			* it under the terms of the GNU General Public License as published by *
9			* the Free Software Foundation; either version 2 of the License, or *
10			* (at your option) any later version. *
11			* *
12			* This program is distributed in the hope that it will be useful, *
13			* but WITHOUT ANY WARRANTY; without even the implied warranty of *
14			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
15			* GNU General Public License for more details. *
16			* *
17			* You should have received a copy of the GNU General Public License *
18			* along with this program; if not, write to the Free Software *
19			* Foundation, Inc., 59 Temple Place, Suite 330, Boston, *
20			* MA 02111-1307 USA *
21			***************************************************************************/
22
23			#include "Stream.h"
24
25			namespace LinuxSampler { namespace gig {
26
27			uint Stream::UnusedStreams = 0;
28
29			/// Returns number of refilled sample points or a value < 0 on error.
30			int Stream::ReadAhead(unsigned long SampleCount) {
31			if (this->State == state_unused) return -1;
32			if (this->State == state_end) return 0;
33			if (!SampleCount) return 0;
34			if (!pRingBuffer->write_space()) return 0;
35
36			long total_readsamples = 0, readsamples = 0;
37			long samplestoread = SampleCount / pSample->Channels;
38			sample_t* pBuf = pRingBuffer->get_write_ptr();
39			bool endofsamplereached;
40
41			// refill the disk stream buffer
42			if (this->DoLoop) { // honor looping
43			total_readsamples = pSample->ReadAndLoop(pBuf, samplestoread, &this->PlaybackState);
44			endofsamplereached = (this->PlaybackState.position >= pSample->SamplesTotal);
45			dmsg(5,("Refilled stream %d with %d (SamplePos: %d)", this->hThis, total_readsamples, this->PlaybackState.position));
46			}
47			else { // normal forward playback
48
49			pSample->SetPos(this->SampleOffset); // recover old position
50
51			do {
52			readsamples = pSample->Read(&pBuf[total_readsamples * pSample->Channels], samplestoread);
53			samplestoread -= readsamples;
54			total_readsamples += readsamples;
55			} while (samplestoread && readsamples > 0);
56
57			// we have to store the position within the sample, because other streams might use the same sample
58			this->SampleOffset = pSample->GetPos();
59
60			endofsamplereached = (SampleOffset >= pSample->SamplesTotal);
61			dmsg(5,("Refilled stream %d with %d (SamplePos: %d)", this->hThis, total_readsamples, this->SampleOffset));
62			}
63
64			// we must delay the increment_write_ptr_with_wrap() after the while() loop because we need to
65			// ensure that we read exactly SampleCount sample, otherwise the buffer wrapping code will fail
66			pRingBuffer->increment_write_ptr_with_wrap(total_readsamples * pSample->Channels);
67
68			// update stream state
69			if (endofsamplereached) SetState(state_end);
70			else SetState(state_active);
71
72			return total_readsamples;
73			}
74
75			void Stream::WriteSilence(unsigned long SilenceSampleWords) {
76			memset(pRingBuffer->get_write_ptr(), 0, SilenceSampleWords);
77			pRingBuffer->increment_write_ptr_with_wrap(SilenceSampleWords);
78			}
79
80			Stream::Stream(uint BufferSize, uint BufferWrapElements) {
81			this->pExportReference = NULL;
82			this->State = state_unused;
83			this->hThis = 0;
84			this->pSample = NULL;
85			this->SampleOffset = 0;
86			this->PlaybackState.position = 0;
87			this->PlaybackState.reverse = false;
88			this->pRingBuffer = new RingBuffer<sample_t>(BufferSize, BufferWrapElements);
89			UnusedStreams++;
90			}
91
92			Stream::~Stream() {
93			Reset();
94			if (pRingBuffer) delete pRingBuffer;
95			}
96
97			/// Called by disk thread to activate the disk stream.
98			void Stream::Launch(Stream::Handle hStream, reference_t* pExportReference, ::gig::Sample* pSample, unsigned long SampleOffset, bool DoLoop) {
99			UnusedStreams--;
100			this->pExportReference = pExportReference;
101			this->hThis = hStream;
102			this->pSample = pSample;
103			this->SampleOffset = SampleOffset;
104			this->PlaybackState.position = SampleOffset;
105			this->PlaybackState.reverse = false;
106			this->PlaybackState.loop_cycles_left = pSample->LoopPlayCount;
107			this->DoLoop = DoLoop;
108			SetState(state_active);
109			}
110
111			}} // namespace LinuxSampler::gig