source: downloads/ogre/Tools/LightwaveConverter/include/lwEnvelope.h @ 20

#ifndef _LWENVELOPE_H_
#define _LWENVELOPE_H_

#include "lwo.h"

#include <iostream>

class lwKey
{
public:
        lwKey(float ntime, float nvalue) : time(ntime), value(nvalue) {}
        float          time;
        float          value;
        unsigned int   shape;               /* ID_TCB, ID_BEZ2, etc. */
        float          tension;
        float          continuity;
        float          bias;
        float          param[ 4 ];
};

typedef vector<lwKey*> vkeys;

inline bool operator < (const lwKey &k1, const lwKey &k2)
{
        return k1.time < k2.time;
}

#define BEH_RESET      0
#define BEH_CONSTANT   1
#define BEH_REPEAT     2
#define BEH_OSCILLATE  3
#define BEH_OFFSET     4
#define BEH_LINEAR     5

class lwEnvelope
{
        float range( float v, float lo, float hi, int *i );
        void hermite( float t, float *h1, float *h2, float *h3, float *h4 );
        float bezier( float x0, float x1, float x2, float x3, float t );
        float bez2_time( float x0, float x1, float x2, float x3, float time, float *t0, float *t1 );
        float bez2( lwKey *key0, lwKey *key1, float time );
        float outgoing( unsigned int key0, unsigned int key1 );
        float incoming( unsigned int key0, unsigned int key1 );
        
public:
        lwEnvelope()
        {
                name = 0;
        }

        ~lwEnvelope()
        {
                if (name) free(name);
                unsigned int i;
                for (i=0; i<keys.size(); delete keys[i++]);
                for (i=0; i<cfilters.size(); delete cfilters[i++]);
        }
        
        float evaluate( float time );
        lwKey *addKey( float time, float value );

        int       index;
        int       type;
        char     *name;
        vkeys     keys;                /* linked list of keys */
        int       behavior[ 2 ];       /* pre and post (extrapolation) */
        vplugins  cfilters;            /* linked list of channel filters */
        int       ncfilters;
};

typedef vector<lwEnvelope*> venvelopes;

#endif // _LWENVELOPE_H_