Collidoscope

/*

 Copyright (C) 2015  Fiore Martin

 Copyright (C) 2016  Queen Mary University of London 

 Author: Fiore Martin

 This file is part of Collidoscope.

 Collidoscope 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 3 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, see <http://www.gnu.org/licenses/>.

*/

#pragma once

#include "cinder/app/App.h"

#include "cinder/gl/gl.h"

#include "cinder/gl/Batch.h"

#include "Chunk.h"

#include "DrawInfo.h"

#ifdef USE_PARTICLES

#include "ParticleController.h"

#endif 

#include "cinder/Color.h"

#include "cinder/PolyLine.h"

#include "cinder/Rand.h"

#include <vector>

#include <map>

class DrawInfo;

typedef int SynthID;

using ci::ivec2;

using ci::vec2;

using ci::Color;

using ci::ColorA;

/**

 * A Cursor is the white thingy that loops through the selection when Collidoscope is played.

 */ 

struct Cursor {

    static const int kNoPosition = -100;

    int pos;

    double lastUpdate;

};

/**

 * Collidoscope's graphical wave 

 *

 */ 

class Wave

{

    friend class ParticleController;

public:

    /**

     * The selection of the wave that is controlled by the big horizontal knob

     *

     */ 

    class Selection {

    public:

        Selection( Wave * w, Color color );

        /** Sets the start of selection. start is the index of the first chunk of the selection  */

        void setStart( size_t start );

        /** Sets the size of selection. size is the number of chunks the selection is made of */

        void setSize( size_t size );

        /** The particle spread parameter affects the size of the cloud of particles

         *  The cloud is the visual counterpart of the grain duration coefficient in sound.

         *  Indeed spread accepts values from 1 to 8, exactly as the duration coefficient

         */

        void inline setParticleSpread( float spread ){

            mParticleSpread = spread;

        }

        size_t getStart(void) const { return mSelectionStart; }

        size_t getEnd(void) const { return mSelectionEnd; }

        size_t inline getSize(void) const { 

            if (mNull)

                return 0;

            else

                return 1 + mSelectionEnd - mSelectionStart; 

        }

        float inline  getParticleSpread() const { return mParticleSpread; }

        /** When selection is null no selection is showed on the wave */

        inline void setToNull(){

            mParticleSpread = 1.0f;

            mNull = true;

        }

        inline bool isNull() const{

            return mNull;

        }

        inline const Color & getColor() const{

            return mColor;

        }

    private:

        size_t mSelectionStart;

        size_t mSelectionEnd;

        float mParticleSpread;

        bool mNull = true;

        Color mColor;

        Wave * mWave;

    }; // class Selection

#ifdef USE_PARTICLES

    ParticleController mParticleController;

#endif 

    /* Maps id of the synth to cursor. There is one cursor for each Synth being played */

    std::map < SynthID, Cursor > mCursors;

    /** Holds the positions of the cursor, namely on which chunk the cursor is currently on */

    std::vector<int> mCursorsPos;

public:

    // value used to identify the loop for cursor position 

    static const int kLoopNote = -1;

    static const cinder::Color CURSOR_CLR;

    static const int MAX_DURATION = 8;

#ifdef USE_PARTICLES

    static const int PARTICLESIZE_COEFF = 40;

#endif

    /** Resetting a wave makes it shrink until it disappears. Each time a new sample is recorded, the wave is reset.

     *  \param onlyChunks if false the selection is also set to null, if true only the chunks are reset

     */

    void reset(bool onlyChunks);

    /** sets top and bottom values for the chunk. 

     * \a bottom and \a top are in audio coordinates [-1.0, 1.0]

     */

    void setChunk(size_t index, float bottom, float top);

    const Chunk & getChunk(size_t index);

    /** Places the cursor on the wave. Every cursor is associated to a synth voice of the audio engine. 

     *  The synth id identifies uniquely the cursor in the internal map of the wave.

     *  If the cursor doesn't exist it is created */

    inline void setCursorPos( SynthID id, int pos, const DrawInfo& di ){

        Cursor & cursor = mCursors[id];

        cursor.pos = pos;

        cursor.lastUpdate = ci::app::getElapsedSeconds();

#ifdef USE_PARTICLES

        // The idea is that, if the duration is greater than 1.0, the cursor continues in form of particles.

        // The smaller the selection the more particles; the bigger the duration the more particles. 

        if (mSelection.getParticleSpread() > 1.0f){

            /* amountCoeff ranges from 1/8 to 1 */

            const float amountCoeff = (mSelection.getParticleSpread() / MAX_DURATION);

            /* get radom point within seleciton as center of the particle */

            vec2 centrePoint;

            const int randomChunkIndex = ci::Rand::randInt(mSelection.getStart(), mSelection.getEnd() );

            centrePoint.x = di.flipX( 1 + (randomChunkIndex * (2 + Chunk::kWidth)) + Chunk::kWidth / 2 );

            centrePoint.y = di.flipY( di.audioToHeigt(0.0) );

            const float wavePixelLen = mNumChunks * ( 2 + Chunk::kWidth);

            centrePoint.x *= float(di.getWindowWidth()) / wavePixelLen;

            mParticleController.addParticles(

                std::max( 1, (int)(amountCoeff * ParticleController::kMaxParticleAdd * mFilterCoeff) ), // amount of particles to add 

                centrePoint,

                mSelection.getParticleSpread() * PARTICLESIZE_COEFF   // size of the cloud 

                );

        }

#endif

    }

    void update( double secondsPerChunk, const DrawInfo& di );

    void removeCursor( SynthID id ) { mCursors.erase( id ); }

    /** Sets the transparency of this wave. \a alpha ranges from 0 to 1 */

    inline void setselectionAlpha(float alpha){ mFilterCoeff = alpha;}

    void draw( const DrawInfo& di );

    Selection& getSelection() { return mSelection; };

    size_t getSize() const{ return mChunks.size();  }

    void setScopePoint(int index, float audioVal);

    Wave( size_t numChunks, Color selectionColor );

    /** no copies */

    Wave( const Wave &copy ) = delete;

    Wave & operator=(const Wave &copy) = delete;

private:

    const size_t mNumChunks;

    std::vector<Chunk> mChunks;

    Selection mSelection;

    cinder::Color mColor;

    // How much filter is applied in audio. It affects the alpha value of the selection color.

    float mFilterCoeff;

    // cinder gl batch for batch drawing 

    ci::gl::BatchRef mChunkBatch;

};