controlparticles.cpp

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// --------------------------------------------------------------------------
//
// El'Beem - the visual lattice boltzmann freesurface simulator
// All code distributed as part of El'Beem is covered by the version 2 of the 
// GNU General Public License. See the file COPYING for details.  
//
// Copyright 2008 Nils Thuerey , Richard Keiser, Mark Pauly, Ulrich Ruede
//
// implementation of control particle handling
//
// --------------------------------------------------------------------------

// indicator for LBM inclusion
#include "ntl_geometrymodel.h"
#include "ntl_world.h"
#include "solver_class.h"
#include "controlparticles.h"
#include "mvmcoords.h"
#include <zlib.h>

#ifndef sqrtf
#define sqrtf sqrt
#endif

// brute force circle test init in initTimeArray
// replaced by mDebugInit
//#define CP_FORCECIRCLEINIT 0


void ControlParticles::initBlenderTest() {
    mPartSets.clear();

    ControlParticleSet cps;
    mPartSets.push_back(cps);
    int setCnt = mPartSets.size()-1;
    ControlParticle p; 

    // set for time zero
    mPartSets[setCnt].time = 0.;

    // add single particle 
    p.reset();
    p.pos = LbmVec(0.5, 0.5, -0.5);
    mPartSets[setCnt].particles.push_back(p);

    // add second set for animation
    mPartSets.push_back(cps);
    setCnt = mPartSets.size()-1;
    mPartSets[setCnt].time = 0.15;

    // insert new position
    p.reset();
    p.pos = LbmVec(-0.5, -0.5, 0.5);
    mPartSets[setCnt].particles.push_back(p);

    // applyTrafos();
    initTime(0. , 1.);
}

// blender control object gets converted to mvm flui control object
int ControlParticles::initFromObject(ntlGeometryObjModel *model) {
    vector<ntlTriangle> triangles;
    vector<ntlVec3Gfx> vertices;
    vector<ntlVec3Gfx> normals;
    
    /*
    model->loadBobjModel(string(infile));
    
    model->setLoaded(true);
    
    model->setGeoInitId(gid);
    
    
    printf("a animated? %d\n", model->getIsAnimated());
    printf("b animated? %d\n", model->getMeshAnimated());
    */
    
    model->setGeoInitType(FGI_FLUID);
    
    model->getTriangles(mCPSTimeStart, &triangles, &vertices, &normals, 1 ); 
    // model->applyTransformation(mCPSTimeStart, &vertices, &normals, 0, vertices.size(), true);
    
    // valid mesh?
    if(triangles.size() <= 0) {
        return 0;
    }

    ntlRenderGlobals *glob = new ntlRenderGlobals;
    ntlScene *genscene = new ntlScene( glob, false );
    genscene->addGeoClass(model);
    genscene->addGeoObject(model);
    genscene->buildScene(0., false);
    char treeFlag = (1<<(4+model->getGeoInitId()));

    ntlTree *tree = new ntlTree( 
    15, 8,  // TREEwarning - fixed values for depth & maxtriangles here...
    genscene, treeFlag );

    // TODO? use params
    ntlVec3Gfx start,end;
    model->getExtends(start,end);
    /*
    printf("start - x: %f, y: %f, z: %f\n", start[0], start[1], start[2]);
    printf("end   - x: %f, y: %f, z: %f\n", end[0], end[1], end[2]);
    printf("mCPSWidth: %f\n");
*/
    LbmFloat width = mCPSWidth;
    if(width<=LBM_EPSILON) { errMsg("ControlParticles::initFromMVMCMesh","Invalid mCPSWidth! "<<mCPSWidth); width=mCPSWidth=0.1; }
    ntlVec3Gfx org = start+ntlVec3Gfx(width*0.5);
    gfxReal distance = -1.;
    vector<ntlVec3Gfx> inspos;
    
    // printf("distance: %f, width: %f\n", distance, width);
    
    while(org[2]<end[2]) {
        while(org[1]<end[1]) {
            while(org[0]<end[0]) {
                if(checkPointInside(tree, org, distance)) {
                    inspos.push_back(org);
                }
                // TODO optimize, use distance
                org[0] += width;
            }
            org[1] += width;
            org[0] = start[0];
        }
        org[2] += width;
        org[1] = start[1];
    }
    
    // printf("inspos.size(): %d\n", inspos.size());

    MeanValueMeshCoords mvm;
    mvm.calculateMVMCs(vertices,triangles, inspos, mCPSWeightFac);
    vector<ntlVec3Gfx> ninspos;
    mvm.transfer(vertices, ninspos);

    // init first set, check dist
    ControlParticleSet firstcps; //T
    mPartSets.push_back(firstcps);
    mPartSets[mPartSets.size()-1].time = mCPSTimeStart;
    vector<bool> useCP;

    for(int i=0; i<(int)inspos.size(); i++) {
        ControlParticle p; p.reset();
        p.pos = vec2L(inspos[i]);
        
        bool usecpv = true;

        mPartSets[mPartSets.size()-1].particles.push_back(p);
        useCP.push_back(usecpv);
    }

    // init further sets, temporal mesh sampling
    double tsampling = mCPSTimestep;
    // printf("tsampling: %f, ninspos.size(): %d, mCPSTimeEnd: %f\n", tsampling, ninspos.size(), mCPSTimeEnd);
    
    int tcnt=0;
    for(double t=mCPSTimeStart+tsampling; ((t<mCPSTimeEnd) && (ninspos.size()>0.)); t+=tsampling) {
        ControlParticleSet nextcps; //T
        mPartSets.push_back(nextcps);
        mPartSets[mPartSets.size()-1].time = (gfxReal)t;

        vertices.clear(); triangles.clear(); normals.clear();
        model->getTriangles(t, &triangles, &vertices, &normals, 1 );
        mvm.transfer(vertices, ninspos);
        
        tcnt++;
        for(size_t i=0; i < ninspos.size(); i++) {
            
            if(useCP[i]) {
                ControlParticle p; p.reset();
                p.pos = vec2L(ninspos[i]);
                mPartSets[mPartSets.size()-1].particles.push_back(p);
            }
        }
    }
    
    model->setGeoInitType(FGI_CONTROL);

    delete tree;
    delete genscene;
    delete glob;
    
    // do reverse here
    if(model->getGeoPartSlipValue())
    {
        mirrorTime();
    }
    
    return 1;
}


// init all zero / defaults for a single particle
void ControlParticle::reset() {
    pos = LbmVec(0.,0.,0.);
    vel = LbmVec(0.,0.,0.);
    influence = 1.;
    size = 1.;
#ifndef LBMDIM
#ifdef MAIN_2D
    rotaxis = LbmVec(0.,1.,0.); // SPH xz
#else // MAIN_2D
    // 3d - roate in xy plane, vortex
    rotaxis = LbmVec(0.,0.,1.);
    // 3d - rotate for wave
    //rotaxis = LbmVec(0.,1.,0.);
#endif // MAIN_2D
#else // LBMDIM
    rotaxis = LbmVec(0.,1.,0.); // LBM xy , is swapped afterwards
#endif // LBMDIM

    density = 0.;
    densityWeight = 0.;
    avgVelAcc = avgVel = LbmVec(0.);
    avgVelWeight = 0.;
}


// default preset/empty init
ControlParticles::ControlParticles() :
    _influenceTangential(0.f),
    _influenceAttraction(0.f),
    _influenceVelocity(0.f),
    _influenceMaxdist(0.f),
    _radiusAtt(1.0f),
    _radiusVel(1.0f),
    _radiusMinMaxd(2.0f),
    _radiusMaxd(3.0f),
    _currTime(-1.0), _currTimestep(1.),
    _initTimeScale(1.), 
    _initPartOffset(0.), _initPartScale(1.),
    _initLastPartOffset(0.), _initLastPartScale(1.),
    _initMirror(""),
    _fluidSpacing(1.), _kernelWeight(-1.),
    _charLength(1.), _charLengthInv(1.),
    mvCPSStart(-10000.), mvCPSEnd(10000.),
    mCPSWidth(0.1), mCPSTimestep(0.02), // was 0.05
    mCPSTimeStart(0.), mCPSTimeEnd(0.5), mCPSWeightFac(1.),
    mDebugInit(0)
{
    _radiusAtt = 0.15f;
    _radiusVel = 0.15f;
    _radiusMinMaxd = 0.16f;
    _radiusMaxd = 0.3;

    _influenceAttraction = 0.f;
    _influenceTangential = 0.f;
    _influenceVelocity = 0.f;
    // 3d tests */
}


 
ControlParticles::~ControlParticles() {
    // nothing to do...
}

LbmFloat ControlParticles::getControlTimStart() {
    if(mPartSets.size()>0) { return mPartSets[0].time; }
    return -1000.;
}
LbmFloat ControlParticles::getControlTimEnd() {
    if(mPartSets.size()>0) { return mPartSets[mPartSets.size()-1].time; }
    return -1000.;
}

// calculate for delta t
void ControlParticles::setInfluenceVelocity(LbmFloat set, LbmFloat dt) {
    const LbmFloat dtInter = 0.01;
    LbmFloat facFv = 1.-set; //cparts->getInfluenceVelocity();
    // mLevel[mMaxRefine].timestep
    LbmFloat facNv = (LbmFloat)( 1.-pow( (double)facFv, (double)(dt/dtInter)) );
    //errMsg("vwcalc","ts:"<<dt<< " its:"<<(dt/dtInter) <<" fv"<<facFv<<" nv"<<facNv<<" test:"<< pow( (double)(1.-facNv),(double)(dtInter/dt))  );
    _influenceVelocity = facNv;
}

int ControlParticles::initExampleSet()
{
    // unused
    return 0;
}

int ControlParticles::getTotalSize()
{
    int s=0;
    for(int i=0; i<(int)mPartSets.size(); i++) {
        s+= mPartSets[i].particles.size();
    }
    return s;
}

// --------------------------------------------------------------------------
// load positions & timing from text file
// WARNING - make sure file has unix format, no win/dos linefeeds...
#define LINE_LEN 100
int ControlParticles::initFromTextFile(string filename)
{
    /*
    const bool debugRead = false;
    char line[LINE_LEN];
    line[LINE_LEN-1] = '\0';
    mPartSets.clear();
    if(filename.size()<2) return 0;

    // HACK , use "cparts" suffix as old
    // e.g. "cpart2" as new
    if(filename[ filename.size()-1 ]=='s') {
        return initFromTextFileOld(filename);
    }

    FILE *infile = fopen(filename.c_str(), "r");
    if(!infile) {
        errMsg("ControlParticles::initFromTextFile","unable to open '"<<filename<<"' " );
        // try to open as gz sequence
        if(initFromBinaryFile(filename)) { return 1; }
        // try mesh MVCM generation
        if(initFromMVCMesh(filename)) { return 1; }
        // failed...
        return 0;
    }

    int haveNo = false;
    int haveScale = false;
    int haveTime = false;
    int noParts = -1;
    int partCnt = 0;
    int setCnt = 0;
    //ControlParticle p; p.reset();
    // scale times by constant factor while reading
    LbmFloat timeScale= 1.0;
    int lineCnt = 0;
    bool abortParse = false;
#define LASTCP mPartSets[setCnt].particles[ mPartSets[setCnt].particles.size()-1 ]

    while( (!feof(infile)) && (!abortParse)) {
        lineCnt++;
        fgets(line, LINE_LEN, infile);

        //if(debugRead) printf("\nDEBUG%d r '%s'\n",lineCnt, line);
        if(!line) continue;
        size_t len = strlen(line);

        // skip empty lines and comments (#,//)
        if(len<1) continue;
        if( (line[0]=='#') || (line[0]=='\n') ) continue;
        if((len>1) && (line[0]=='/' && line[1]=='/')) continue;

        // debug remove newline
        if((len>=1)&&(line[len-1]=='\n')) line[len-1]='\0';

        switch(line[0]) {

        case 'N': { // total number of particles, more for debugging...
            noParts = atoi(line+2);
            if(noParts<=0) {
                errMsg("ControlParticles::initFromTextFile","file '"<<filename<<"' - invalid no of particles "<<noParts);
                mPartSets.clear(); fclose(infile); return 0;
            }
            if(debugRead) printf("CPDEBUG%d no parts '%d'\n",lineCnt, noParts );
            haveNo = true;
            } break;

        case 'T': { // global time scale
            timeScale *= (LbmFloat)atof(line+2);
            if(debugRead) printf("ControlParticles::initFromTextFile - line %d , set timescale '%f', org %f\n",lineCnt, timeScale , _initTimeScale);
            if(timeScale==0.) { fprintf(stdout,"ControlParticles::initFromTextFile - line %d ,error: timescale = 0.! reseting to 1 ...\n",lineCnt); timeScale=1.; }
            haveScale = true;
            } break;

        case 'I': { // influence settings, overrides others as of now...
            float val = (LbmFloat)atof(line+3);
            const char *setvar = "[invalid]";
            switch(line[1]) {
                //case 'f': { _influenceFalloff = val; setvar = "falloff"; } break;
                case 't': { _influenceTangential = val; setvar = "tangential"; } break;
                case 'a': { _influenceAttraction = val; setvar = "attraction"; } break;
                case 'v': { _influenceVelocity = val; setvar = "velocity"; } break;
                case 'm': { _influenceMaxdist = val; setvar = "maxdist"; } break;
                default: 
                    fprintf(stdout,"ControlParticles::initFromTextFile (%s) - line %d , invalid influence setting %c, %f\n",filename.c_str() ,lineCnt, line[1], val);
            }
            if(debugRead) printf("CPDEBUG%d set influence '%s'=%f \n",lineCnt, setvar, val);
            } break;

        case 'R': { // radius settings, overrides others as of now...
            float val = (LbmFloat)atof(line+3);
            const char *setvar = "[invalid]";
            switch(line[1]) {
                case 'a': { _radiusAtt = val; setvar = "r_attraction"; } break;
                case 'v': { _radiusVel = val; setvar = "r_velocity"; } break;
                case 'm': { _radiusMaxd = val; setvar = "r_maxdist"; } break;
                default: 
                    fprintf(stdout,"ControlParticles::initFromTextFile (%s) - line %d , invalid influence setting %c, %f\n",filename.c_str() ,lineCnt, line[1], val);
            }
            if(debugRead) printf("CPDEBUG%d set influence '%s'=%f \n",lineCnt, setvar, val);
            } break;

        case 'S': { // new particle set at time T
            ControlParticleSet cps;
            mPartSets.push_back(cps);
            setCnt = (int)mPartSets.size()-1;

            LbmFloat val = (LbmFloat)atof(line+2);
            mPartSets[setCnt].time = val * timeScale;
            if(debugRead) printf("CPDEBUG%d new set, time '%f', %d\n",lineCnt, mPartSets[setCnt].time, setCnt );
            haveTime = true;
            partCnt = -1;
            } break;

        case 'P':   // new particle with pos
        case 'n': { // new particle without pos
                if((!haveTime)||(setCnt<0)) { fprintf(stdout,"ControlParticles::initFromTextFile - line %d ,error: set missing!\n",lineCnt); abortParse=true; break; }
                partCnt++;
                if(partCnt>=noParts) {
                    if(debugRead) printf("CPDEBUG%d partset done \n",lineCnt);
                    haveTime = false;
                } else {
                    ControlParticle p; p.reset();
                    mPartSets[setCnt].particles.push_back(p);
                }
            } 
            // only new part, or new with pos?
            if(line[0] == 'n') break;

        // particle properties

        case 'p': { // new particle set at time T
            if((!haveTime)||(setCnt<0)||(mPartSets[setCnt].particles.size()<1)) { fprintf(stdout,"ControlParticles::initFromTextFile - line %d ,error|p: particle missing!\n",lineCnt); abortParse=true; break; }
            float px=0.,py=0.,pz=0.;
            if( sscanf(line+2,"%f %f %f",&px,&py,&pz) != 3) {
                fprintf(stdout,"CPDEBUG%d, unable to parse position!\n",lineCnt); abortParse=true; break; 
            }
            if(!(finite(px)&&finite(py)&&finite(pz))) { px=py=pz=0.; }
            LASTCP.pos[0] = px;
            LASTCP.pos[1] = py;
            LASTCP.pos[2] = pz; 
            if(debugRead) printf("CPDEBUG%d part%d,%d: position %f,%f,%f \n",lineCnt,setCnt,partCnt, px,py,pz);
            } break;

        case 's': { // particle size
            if((!haveTime)||(setCnt<0)||(mPartSets[setCnt].particles.size()<1)) { fprintf(stdout,"ControlParticles::initFromTextFile - line %d ,error|s: particle missing!\n",lineCnt); abortParse=true; break; }
            float ps=1.;
            if( sscanf(line+2,"%f",&ps) != 1) {
                fprintf(stdout,"CPDEBUG%d, unable to parse size!\n",lineCnt); abortParse=true; break; 
            }
            if(!(finite(ps))) { ps=0.; }
            LASTCP.size = ps;
            if(debugRead) printf("CPDEBUG%d part%d,%d: size %f \n",lineCnt,setCnt,partCnt, ps);
            } break;

        case 'i': { // particle influence
            if((!haveTime)||(setCnt<0)||(mPartSets[setCnt].particles.size()<1)) { fprintf(stdout,"ControlParticles::initFromTextFile - line %d ,error|i: particle missing!\n",lineCnt); abortParse=true; break; }
            float pinf=1.;
            if( sscanf(line+2,"%f",&pinf) != 1) {
                fprintf(stdout,"CPDEBUG%d, unable to parse size!\n",lineCnt); abortParse=true; break; 
            }
            if(!(finite(pinf))) { pinf=0.; }
            LASTCP.influence = pinf;
            if(debugRead) printf("CPDEBUG%d part%d,%d: influence %f \n",lineCnt,setCnt,partCnt, pinf);
            } break;

        case 'a': { // rotation axis
            if((!haveTime)||(setCnt<0)||(mPartSets[setCnt].particles.size()<1)) { fprintf(stdout,"ControlParticles::initFromTextFile - line %d ,error|a: particle missing!\n",lineCnt); abortParse=true; break; }
            float px=0.,py=0.,pz=0.;
            if( sscanf(line+2,"%f %f %f",&px,&py,&pz) != 3) {
                fprintf(stdout,"CPDEBUG%d, unable to parse rotaxis!\n",lineCnt); abortParse=true; break; 
            }
            if(!(finite(px)&&finite(py)&&finite(pz))) { px=py=pz=0.; }
            LASTCP.rotaxis[0] = px;
            LASTCP.rotaxis[1] = py;
            LASTCP.rotaxis[2] = pz; 
            if(debugRead) printf("CPDEBUG%d part%d,%d: rotaxis %f,%f,%f \n",lineCnt,setCnt,partCnt, px,py,pz);
            } break;


        default:
            if(debugRead) printf("CPDEBUG%d ignored: '%s'\n",lineCnt, line );
            break;
        }
    }
    if(debugRead && abortParse) printf("CPDEBUG aborted parsing after set... %d\n",(int)mPartSets.size() );

    // sanity check
    for(int i=0; i<(int)mPartSets.size(); i++) {
        if( (int)mPartSets[i].particles.size()!=noParts) {
            fprintf(stdout,"ControlParticles::initFromTextFile (%s) - invalid no of particles in set %d, is:%d, shouldbe:%d \n",filename.c_str() ,i,(int)mPartSets[i].particles.size(), noParts);
            mPartSets.clear();
            fclose(infile);
            return 0;
        }
    }

    // print stats
    printf("ControlParticles::initFromTextFile (%s): Read %d sets, each %d particles\n",filename.c_str() ,
            (int)mPartSets.size(), noParts );
    if(mPartSets.size()>0) {
        printf("ControlParticles::initFromTextFile (%s): Time: %f,%f\n",filename.c_str() ,mPartSets[0].time, mPartSets[mPartSets.size()-1].time );
    }
    
    // done...
    fclose(infile);
    applyTrafos();
    */
    return 1;
}


int ControlParticles::initFromTextFileOld(string filename)
{
    /*
    const bool debugRead = false;
    char line[LINE_LEN];
    line[LINE_LEN-1] = '\0';
    mPartSets.clear();
    if(filename.size()<1) return 0;

    FILE *infile = fopen(filename.c_str(), "r");
    if(!infile) {
        fprintf(stdout,"ControlParticles::initFromTextFileOld - unable to open '%s'\n",filename.c_str() );
        return 0;
    }

    int haveNo = false;
    int haveScale = false;
    int haveTime = false;
    int noParts = -1;
    int coordCnt = 0;
    int partCnt = 0;
    int setCnt = 0;
    ControlParticle p; p.reset();
    // scale times by constant factor while reading
    LbmFloat timeScale= 1.0;
    int lineCnt = 0;

    while(!feof(infile)) {
        lineCnt++;
        fgets(line, LINE_LEN, infile);

        if(debugRead) printf("\nDEBUG%d r '%s'\n",lineCnt, line);

        if(!line) continue;
        size_t len = strlen(line);

        // skip empty lines and comments (#,//)
        if(len<1) continue;
        if( (line[0]=='#') || (line[0]=='\n') ) continue;
        if((len>1) && (line[0]=='/' && line[1]=='/')) continue;

        // debug remove newline
        if((len>=1)&&(line[len-1]=='\n')) line[len-1]='\0';

        // first read no. of particles
        if(!haveNo) {
            noParts = atoi(line);
            if(noParts<=0) {
                fprintf(stdout,"ControlParticles::initFromTextFileOld - invalid no of particles %d\n",noParts);
                mPartSets.clear();
                fclose(infile);
                return 0;
            }
            if(debugRead) printf("DEBUG%d noparts '%d'\n",lineCnt, noParts );
            haveNo = true;
        } 

        // then read time scale
        else if(!haveScale) {
            timeScale *= (LbmFloat)atof(line);
            if(debugRead) printf("DEBUG%d tsc '%f', org %f\n",lineCnt, timeScale , _initTimeScale);
            haveScale = true;
        } 

        // then get set time
        else if(!haveTime) {
            ControlParticleSet cps;
            mPartSets.push_back(cps);
            setCnt = (int)mPartSets.size()-1;

            LbmFloat val = (LbmFloat)atof(line);
            mPartSets[setCnt].time = val * timeScale;
            if(debugRead) printf("DEBUG%d time '%f', %d\n",lineCnt, mPartSets[setCnt].time, setCnt );
            haveTime = true;
        }

        // default read all parts
        else {
            LbmFloat val = (LbmFloat)atof(line);
            if(debugRead) printf("DEBUG: l%d s%d,particle%d '%f' %d,%d/%d\n",lineCnt,(int)mPartSets.size(),(int)mPartSets[setCnt].particles.size(), val ,coordCnt,partCnt,noParts);
            p.pos[coordCnt] = val;
            coordCnt++;
            if(coordCnt>=3) {
                mPartSets[setCnt].particles.push_back(p);
                p.reset();
                coordCnt=0;
                partCnt++;
            }
            if(partCnt>=noParts) {
                partCnt = 0;
                haveTime = false;
            }
            //if(debugRead) printf("DEBUG%d par2 %d,%d/%d\n",lineCnt, coordCnt,partCnt,noParts);
        }
        //read pos, vel ...
    }

    // sanity check
    for(int i=0; i<(int)mPartSets.size(); i++) {
        if( (int)mPartSets[i].particles.size()!=noParts) {
            fprintf(stdout,"ControlParticles::initFromTextFileOld - invalid no of particles in set %d, is:%d, shouldbe:%d \n",i,(int)mPartSets[i].particles.size(), noParts);
            mPartSets.clear();
            fclose(infile);
            return 0;
        }
    }
    // print stats
    printf("ControlParticles::initFromTextFileOld: Read %d sets, each %d particles\n",
            (int)mPartSets.size(), noParts );
    if(mPartSets.size()>0) {
        printf("ControlParticles::initFromTextFileOld: Time: %f,%f\n",mPartSets[0].time, mPartSets[mPartSets.size()-1].time );
    }
    
    // done...
    fclose(infile);
    applyTrafos();
    */
    return 1;
}

// load positions & timing from gzipped binary file
int ControlParticles::initFromBinaryFile(string filename) {
    mPartSets.clear();
    if(filename.size()<1) return 0;
    int fileNotFound=0;
    int fileFound=0;
    char ofile[256];

    for(int set=0; ((set<10000)&&(fileNotFound<10)); set++) {
        snprintf(ofile,256,"%s%04d.gz",filename.c_str(),set);
        //errMsg("ControlParticle::initFromBinaryFile","set"<<set<<" notf"<<fileNotFound<<" ff"<<fileFound);

        gzFile gzf;
        gzf = gzopen(ofile, "rb");
        if (!gzf) {
            //errMsg("ControlParticles::initFromBinaryFile","Unable to open file for reading '"<<ofile<<"' "); 
            fileNotFound++;
            continue;
        }
        fileNotFound=0;
        fileFound++;

        ControlParticleSet cps;
        mPartSets.push_back(cps);
        int setCnt = (int)mPartSets.size()-1;
        //LbmFloat val = (LbmFloat)atof(line+2);
        mPartSets[setCnt].time = (gfxReal)set;

        int totpart = 0;
        gzread(gzf, &totpart, sizeof(totpart));

        for(int a=0; a<totpart; a++) {
            int ptype=0;
            float psize=0.0;
            ntlVec3Gfx ppos,pvel;
            gzread(gzf, &ptype, sizeof( ptype )); 
            gzread(gzf, &psize, sizeof( float )); 

            for(int j=0; j<3; j++) { gzread(gzf, &ppos[j], sizeof( float )); }
            for(int j=0; j<3; j++) { gzread(gzf, &pvel[j], sizeof( float )); }

            ControlParticle p; 
            p.reset();
            p.pos = vec2L(ppos);
            mPartSets[setCnt].particles.push_back(p);
        } 

        gzclose(gzf);
        //errMsg("ControlParticle::initFromBinaryFile","Read set "<<ofile<<", #"<<mPartSets[setCnt].particles.size() ); // DEBUG
    } // sets

    if(fileFound==0) return 0;
    applyTrafos();
    return 1;
}

int globCPIProblems =0;
bool ControlParticles::checkPointInside(ntlTree *tree, ntlVec3Gfx org, gfxReal &distance) {
    // warning - stripped down version of geoInitCheckPointInside
    const int globGeoInitDebug = 0;
    const int  flags = FGI_FLUID;
    org += ntlVec3Gfx(0.0001);
    ntlVec3Gfx dir = ntlVec3Gfx(1.0, 0.0, 0.0);
    int OId = -1;
    ntlRay ray(org, dir, 0, 1.0, NULL);
    bool done = false;
    bool inside = false;
    int mGiObjInside = 0; 
    LbmFloat mGiObjDistance = -1.0; 
    LbmFloat giObjFirstHistSide = 0; 
    
    // if not inside, return distance to first hit
    gfxReal firstHit=-1.0;
    int     firstOId = -1;
    if(globGeoInitDebug) errMsg("IIIstart"," isect "<<org);

    while(!done) {
        // find first inside intersection
        ntlTriangle *triIns = NULL;
        distance = -1.0;
        ntlVec3Gfx normal(0.0);
        tree->intersectX(ray,distance,normal, triIns, flags, true);
        if(triIns) {
            ntlVec3Gfx norg = ray.getOrigin() + ray.getDirection()*distance;
            LbmFloat orientation = dot(normal, dir);
            OId = triIns->getObjectId();
            if(orientation<=0.0) {
                // outside hit
                normal *= -1.0;
                mGiObjInside++;
                if(giObjFirstHistSide==0) giObjFirstHistSide = 1;
                if(globGeoInitDebug) errMsg("IIO"," oid:"<<OId<<" org"<<org<<" norg"<<norg<<" orient:"<<orientation);
            } else {
                // inside hit
                mGiObjInside++;
                if(mGiObjDistance<0.0) mGiObjDistance = distance;
                if(globGeoInitDebug) errMsg("III"," oid:"<<OId<<" org"<<org<<" norg"<<norg<<" orient:"<<orientation);
                if(giObjFirstHistSide==0) giObjFirstHistSide = -1;
            }
            norg += normal * getVecEpsilon();
            ray = ntlRay(norg, dir, 0, 1.0, NULL);
            // remember first hit distance, in case we're not 
            // inside anything
            if(firstHit<0.0) {
                firstHit = distance;
                firstOId = OId;
            }
        } else {
            // no more intersections... return false
            done = true;
        }
    }

    distance = -1.0;
    if(mGiObjInside>0) {
        bool mess = false;
        if((mGiObjInside%2)==1) {
            if(giObjFirstHistSide != -1) mess=true;
        } else {
            if(giObjFirstHistSide !=  1) mess=true;
        }
        if(mess) {
            // ?
            //errMsg("IIIproblem","At "<<org<<" obj  inside:"<<mGiObjInside<<" firstside:"<<giObjFirstHistSide );
            globCPIProblems++;
            mGiObjInside++; // believe first hit side...
        }
    }

    if(globGeoInitDebug) errMsg("CHIII"," ins="<<mGiObjInside<<" t"<<mGiObjDistance<<" d"<<distance);
    if(((mGiObjInside%2)==1)&&(mGiObjDistance>0.0)) {
        if(  (distance<0.0)                             || // first intersection -> good
                ((distance>0.0)&&(distance>mGiObjDistance)) // more than one intersection -> use closest one
            ) {                     
            distance = mGiObjDistance;
            OId = 0;
            inside = true;
        } 
    }

    if(!inside) {
        distance = firstHit;
        OId = firstOId;
    }
    if(globGeoInitDebug) errMsg("CHIII","ins"<<inside<<"  fh"<<firstHit<<" fo"<<firstOId<<" - h"<<distance<<" o"<<OId);

    return inside;
}
int ControlParticles::initFromMVCMesh(string filename) {
    myTime_t mvmstart = getTime(); 
    ntlGeometryObjModel *model = new ntlGeometryObjModel();
    int gid=1;
    char infile[256];
    vector<ntlTriangle> triangles;
    vector<ntlVec3Gfx> vertices;
    vector<ntlVec3Gfx> normals;
    snprintf(infile,256,"%s.bobj.gz", filename.c_str() );
    model->loadBobjModel(string(infile));
    model->setLoaded(true);
    model->setGeoInitId(gid);
    model->setGeoInitType(FGI_FLUID);
    debMsgStd("ControlParticles::initFromMVMCMesh",DM_MSG,"infile:"<<string(infile) ,4);

    //getTriangles(double t,  vector<ntlTriangle> *triangles, vector<ntlVec3Gfx> *vertices, vector<ntlVec3Gfx> *normals, int objectId );
    model->getTriangles(mCPSTimeStart, &triangles, &vertices, &normals, 1 ); 
    debMsgStd("ControlParticles::initFromMVMCMesh",DM_MSG," tris:"<<triangles.size()<<" verts:"<<vertices.size()<<" norms:"<<normals.size() , 2);
    
    // valid mesh?
    if(triangles.size() <= 0) {
        return 0;
    }

    ntlRenderGlobals *glob = new ntlRenderGlobals;
    ntlScene *genscene = new ntlScene( glob, false );
    genscene->addGeoClass(model);
    genscene->addGeoObject(model);
    genscene->buildScene(0., false);
    char treeFlag = (1<<(4+gid));

    ntlTree *tree = new ntlTree( 
            15, 8,  // TREEwarning - fixed values for depth & maxtriangles here...
            genscene, treeFlag );

    // TODO? use params
    ntlVec3Gfx start,end;
    model->getExtends(start,end);

    LbmFloat width = mCPSWidth;
    if(width<=LBM_EPSILON) { errMsg("ControlParticles::initFromMVMCMesh","Invalid mCPSWidth! "<<mCPSWidth); width=mCPSWidth=0.1; }
    ntlVec3Gfx org = start+ntlVec3Gfx(width*0.5);
    gfxReal distance = -1.;
    vector<ntlVec3Gfx> inspos;
    int approxmax = (int)( ((end[0]-start[0])/width)*((end[1]-start[1])/width)*((end[2]-start[2])/width) );

    debMsgStd("ControlParticles::initFromMVMCMesh",DM_MSG,"start"<<start<<" end"<<end<<" w="<<width<<" maxp:"<<approxmax, 5);
    while(org[2]<end[2]) {
        while(org[1]<end[1]) {
            while(org[0]<end[0]) {
                if(checkPointInside(tree, org, distance)) {
                    inspos.push_back(org);
                    //inspos.push_back(org+ntlVec3Gfx(width));
                    //inspos.push_back(start+end*0.5);
                }
                // TODO optimize, use distance
                org[0] += width;
            }
            org[1] += width;
            org[0] = start[0];
        }
        org[2] += width;
        org[1] = start[1];
    }
    debMsgStd("ControlParticles::initFromMVMCMesh",DM_MSG,"points: "<<inspos.size()<<" initproblems: "<<globCPIProblems,5 );

    MeanValueMeshCoords mvm;
    mvm.calculateMVMCs(vertices,triangles, inspos, mCPSWeightFac);
    vector<ntlVec3Gfx> ninspos;
    mvm.transfer(vertices, ninspos);

    // init first set, check dist
    ControlParticleSet firstcps; //T
    mPartSets.push_back(firstcps);
    mPartSets[mPartSets.size()-1].time = (gfxReal)0.;
    vector<bool> useCP;
    bool debugPos=false;

    for(int i=0; i<(int)inspos.size(); i++) {
        ControlParticle p; p.reset();
        p.pos = vec2L(inspos[i]);
        //errMsg("COMP "," "<<inspos[i]<<" vs "<<ninspos[i] );
        double cpdist = norm(inspos[i]-ninspos[i]);
        bool usecpv = true;
        if(debugPos) errMsg("COMP "," "<<cpdist<<usecpv);

        mPartSets[mPartSets.size()-1].particles.push_back(p);
        useCP.push_back(usecpv);
    }

    // init further sets, temporal mesh sampling
    double tsampling = mCPSTimestep;
    int totcnt = (int)( (mCPSTimeEnd-mCPSTimeStart)/tsampling ), tcnt=0;
    for(double t=mCPSTimeStart+tsampling; ((t<mCPSTimeEnd) && (ninspos.size()>0.)); t+=tsampling) {
        ControlParticleSet nextcps; //T
        mPartSets.push_back(nextcps);
        mPartSets[mPartSets.size()-1].time = (gfxReal)t;

        vertices.clear(); triangles.clear(); normals.clear();
        model->getTriangles(t, &triangles, &vertices, &normals, 1 );
        mvm.transfer(vertices, ninspos);
        if(tcnt%(totcnt/10)==1) debMsgStd("MeanValueMeshCoords::calculateMVMCs",DM_MSG,"Transferring animation, frame: "<<tcnt<<"/"<<totcnt,5 );
        tcnt++;
        for(int i=0; i<(int)ninspos.size(); i++) {
            if(debugPos) errMsg("COMP "," "<<norm(inspos[i]-ninspos[i]) );
            if(useCP[i]) {
                ControlParticle p; p.reset();
                p.pos = vec2L(ninspos[i]);
                mPartSets[mPartSets.size()-1].particles.push_back(p);
            }
        }
    }

    applyTrafos();

    myTime_t mvmend = getTime(); 
    debMsgStd("ControlParticle::initFromMVMCMesh",DM_MSG,"t:"<<getTimeString(mvmend-mvmstart)<<" ",7 );
    delete tree;
    delete genscene;
    delete glob;
//exit(1); // DEBUG
    return 1;
}

#define TRISWAP(v,a,b) { LbmFloat tmp = (v)[b]; (v)[b]=(v)[a]; (v)[a]=tmp; }
#define TRISWAPALL(v,a,b) {  \
            TRISWAP( (v).pos     ,a,b ); \
            TRISWAP( (v).vel     ,a,b ); \
            TRISWAP( (v).rotaxis ,a,b ); }

// helper function for LBM 2D -> swap Y and Z components everywhere
void ControlParticles::swapCoords(int a, int b) {
    //return;
    for(int i=0; i<(int)mPartSets.size(); i++) {
        for(int j=0; j<(int)mPartSets[i].particles.size(); j++) {
            TRISWAPALL( mPartSets[i].particles[j],a,b );
        }
    }
}

// helper function for LBM 2D -> mirror time
void ControlParticles::mirrorTime() {
    LbmFloat maxtime = mPartSets[mPartSets.size()-1].time;
    const bool debugTimeswap = false;
    
    for(int i=0; i<(int)mPartSets.size(); i++) {
        mPartSets[i].time = maxtime - mPartSets[i].time;
    }

    for(int i=0; i<(int)mPartSets.size()/2; i++) {
        ControlParticleSet cps = mPartSets[i];
        if(debugTimeswap) errMsg("TIMESWAP", " s"<<i<<","<<mPartSets[i].time<<"  and s"<<(mPartSets.size()-1-i)<<","<< mPartSets[mPartSets.size()-1-i].time <<"  mt:"<<maxtime );
        mPartSets[i] = mPartSets[mPartSets.size()-1-i];
        mPartSets[mPartSets.size()-1-i] = cps;
    }

    for(int i=0; i<(int)mPartSets.size(); i++) {
        if(debugTimeswap) errMsg("TIMESWAP", "done: s"<<i<<","<<mPartSets[i].time<<"  "<<mPartSets[i].particles.size() );
    }
}

// apply init transformations
void ControlParticles::applyTrafos() {
    // apply trafos
    for(int i=0; i<(int)mPartSets.size(); i++) {
        mPartSets[i].time *= _initTimeScale;
        /*for(int j=0; j<(int)mPartSets[i].particles.size(); j++) {
            for(int k=0; k<3; k++) {
                mPartSets[i].particles[j].pos[k] *= _initPartScale[k];
                mPartSets[i].particles[j].pos[k] += _initPartOffset[k];
            }
        } now done in initarray */
    }

    // mirror coords...
    for(int l=0; l<(int)_initMirror.length(); l++) {
        switch(_initMirror[l]) {
        case 'X':
        case 'x':
            //printf("ControlParticles::applyTrafos - mirror x\n");
            swapCoords(1,2);
            break;
        case 'Y':
        case 'y':
            //printf("ControlParticles::applyTrafos - mirror y\n");
            swapCoords(0,2);
            break;
        case 'Z':
        case 'z':
            //printf("ControlParticles::applyTrafos - mirror z\n");
            swapCoords(0,1);
            break;
        case 'T':
        case 't':
            //printf("ControlParticles::applyTrafos - mirror time\n");
            mirrorTime();
            break;
        case ' ':
        case '-':
        case '\n':
            break;
        default:
            //printf("ControlParticles::applyTrafos - mirror unknown %c !?\n", _initMirror[l] );
            break;
        }
    }

    // reset 2d positions
#if (CP_PROJECT2D==1) && ( defined(MAIN_2D) || LBMDIM==2 )
    for(size_t j=0; j<mPartSets.size(); j++) 
        for(size_t i=0; i<mPartSets[j].particles.size(); i++) {
            // DEBUG 
            mPartSets[j].particles[i].pos[1] = 0.f;
        }
#endif

#if defined(LBMDIM) 
    //? if( (getenv("ELBEEM_CPINFILE")) || (getenv("ELBEEM_CPOUTFILE")) ){ 
        // gui control test, don swap...
    //? } else {
        //? swapCoords(1,2); // LBM 2D -> swap Y and Z components everywhere
    //? }
#endif

    initTime(0.f, 0.f);
}

#undef TRISWAP

// --------------------------------------------------------------------------
// init for a given time
void ControlParticles::initTime(LbmFloat t, LbmFloat dt) 
{
    //fprintf(stdout, "CPINITTIME init %f\n",t);
    _currTime = t;
    if(mPartSets.size()<1) return;

    // init zero velocities
    initTimeArray(t, _particles);

    // calculate velocities from prev. timestep?
    if(dt>0.) {
        _currTimestep = dt;
        std::vector<ControlParticle> prevparts;
        initTimeArray(t-dt, prevparts);
        LbmFloat invdt = 1.0/dt;
        for(size_t j=0; j<_particles.size(); j++) {
            ControlParticle &p = _particles[j];
            ControlParticle &prevp = prevparts[j];
            for(int k=0; k<3; k++) {
                p.pos[k] *= _initPartScale[k];
                p.pos[k] += _initPartOffset[k];
                prevp.pos[k] *= _initLastPartScale[k];
                prevp.pos[k] += _initLastPartOffset[k];
            }
            p.vel = (p.pos - prevp.pos)*invdt;
        }

        if(0) {
            LbmVec avgvel(0.);
            for(size_t j=0; j<_particles.size(); j++) {
                avgvel += _particles[j].vel;
            }
            avgvel /= (LbmFloat)_particles.size();
            //fprintf(stdout," AVGVEL %f,%f,%f \n",avgvel[0],avgvel[1],avgvel[2]); // DEBUG
        }
    }
}

// helper, init given array
void ControlParticles::initTimeArray(LbmFloat t, std::vector<ControlParticle> &parts) {
    if(mPartSets.size()<1) return;

    if(parts.size()!=mPartSets[0].particles.size()) {
        //fprintf(stdout,"PRES \n");
        parts.resize(mPartSets[0].particles.size());
        // TODO reset all?
        for(size_t j=0; j<parts.size(); j++) {
            parts[j].reset();
        }
    }
    if(parts.size()<1) return;

    // debug inits
    if(mDebugInit==1) {
        // hard coded circle init
        for(size_t j=0; j<mPartSets[0].particles.size(); j++) {
            ControlParticle p = mPartSets[0].particles[j];
            // remember old
            p.density = parts[j].density;
            p.densityWeight = parts[j].densityWeight;
            p.avgVel = parts[j].avgVel;
            p.avgVelAcc = parts[j].avgVelAcc;
            p.avgVelWeight = parts[j].avgVelWeight;
            LbmVec ppos(0.); { // DEBUG
            const float tscale=10.;
            const float tprevo = 0.33;
            const LbmVec toff(50,50,0);
            const LbmVec oscale(30,30,0);
            ppos[0] =  cos(tscale* t - tprevo*(float)j + M_PI -0.1) * oscale[0] + toff[0];
            ppos[1] = -sin(tscale* t - tprevo*(float)j + M_PI -0.1) * oscale[1] + toff[1];
            ppos[2] =                               toff[2]; } // DEBUG
            p.pos = ppos;
            parts[j] = p;
            //errMsg("ControlParticle::initTimeArray","j:"<<j<<" p:"<<parts[j].pos );
        }
        return;
    }
    else if(mDebugInit==2) {
        // hard coded spiral init
        const float tscale=-10.;
        const float tprevo = 0.33;
        LbmVec   toff(50,0,-50);
        const LbmVec oscale(20,20,0);
        toff[2] += 30. * t +30.;
        for(size_t j=0; j<mPartSets[0].particles.size(); j++) {
            ControlParticle p = mPartSets[0].particles[j];
            // remember old
            p.density = parts[j].density;
            p.densityWeight = parts[j].densityWeight;
            p.avgVel = parts[j].avgVel;
            p.avgVelAcc = parts[j].avgVelAcc;
            p.avgVelWeight = parts[j].avgVelWeight;
            LbmVec ppos(0.); 
            ppos[1] =                               toff[2]; 
            LbmFloat zscal = (ppos[1]+100.)/200.;
            ppos[0] =  cos(tscale* t - tprevo*(float)j + M_PI -0.1) * oscale[0]*zscal + toff[0];
            ppos[2] = -sin(tscale* t - tprevo*(float)j + M_PI -0.1) * oscale[1]*zscal + toff[1];
            p.pos = ppos;
            parts[j] = p;

            toff[2] += 0.25;
        }
        return;
    }

    // use first set
    if((t<=mPartSets[0].time)||(mPartSets.size()==1)) {
        //fprintf(stdout,"PINI %f \n", t);
        //parts = mPartSets[0].particles;
        const int i=0;
        for(size_t j=0; j<mPartSets[i].particles.size(); j++) {
            ControlParticle p = mPartSets[i].particles[j];
            // remember old
            p.density = parts[j].density;
            p.densityWeight = parts[j].densityWeight;
            p.avgVel = parts[j].avgVel;
            p.avgVelAcc = parts[j].avgVelAcc;
            p.avgVelWeight = parts[j].avgVelWeight;
            parts[j] = p;
        }
        return;
    }

    for(int i=0; i<(int)mPartSets.size()-1; i++) {
        if((mPartSets[i].time<=t) && (mPartSets[i+1].time>t)) {
            LbmFloat d = mPartSets[i+1].time-mPartSets[i].time;
            LbmFloat f = (t-mPartSets[i].time)/d;
            LbmFloat omf = 1.0f - f;
    
            for(size_t j=0; j<mPartSets[i].particles.size(); j++) {
                ControlParticle *src1=&mPartSets[i  ].particles[j];
                ControlParticle *src2=&mPartSets[i+1].particles[j];
                ControlParticle &p = parts[j];
                // do linear interpolation
                p.pos     = src1->pos * omf     + src2->pos *f;
                p.vel     = LbmVec(0.); // reset, calculated later on src1->vel * omf     + src2->vel *f;
                p.rotaxis = src1->rotaxis * omf + src2->rotaxis *f;
                p.influence = src1->influence * omf + src2->influence *f;
                p.size    = src1->size * omf    + src2->size *f;
                // dont modify: density, densityWeight
            }
        }
    }

    // after last?
    if(t>=mPartSets[ mPartSets.size() -1 ].time) {
        //parts = mPartSets[ mPartSets.size() -1 ].particles;
        const int i= (int)mPartSets.size() -1;
        for(size_t j=0; j<mPartSets[i].particles.size(); j++) {
            ControlParticle p = mPartSets[i].particles[j];
            // restore
            p.density = parts[j].density;
            p.densityWeight = parts[j].densityWeight;
            p.avgVel = parts[j].avgVel;
            p.avgVelAcc = parts[j].avgVelAcc;
            p.avgVelWeight = parts[j].avgVelWeight;
            parts[j] = p;
        }
    }
}




// --------------------------------------------------------------------------

#define DEBUG_MODVEL 0

// recalculate 
void ControlParticles::calculateKernelWeight() {
    const bool debugKernel = true;

    // calculate kernel area with respect to particlesize/cellsize
    LbmFloat kernelw = -1.;
    LbmFloat kernelnorm = -1.;
    LbmFloat krad = (_radiusAtt*0.75); // FIXME  use real cone approximation...?
    //krad = (_influenceFalloff*1.);
#if (CP_PROJECT2D==1) && (defined(MAIN_2D) || LBMDIM==2)
    kernelw = CP_PI*krad*krad;
    kernelnorm = 1.0 / (_fluidSpacing * _fluidSpacing);
#else // 2D
    kernelw = CP_PI*krad*krad*krad* (4./3.);
    kernelnorm = 1.0 / (_fluidSpacing * _fluidSpacing * _fluidSpacing);
#endif // MAIN_2D

    if(debugKernel) debMsgStd("ControlParticles::calculateKernelWeight",DM_MSG,"kw"<<kernelw<<", norm"<<
            kernelnorm<<", w*n="<<(kernelw*kernelnorm)<<", rad"<<krad<<", sp"<<_fluidSpacing<<"  ", 7);
    LbmFloat kernelws = kernelw*kernelnorm;
    _kernelWeight = kernelws;
    if(debugKernel) debMsgStd("ControlParticles::calculateKernelWeight",DM_MSG,"influence f="<<_radiusAtt<<" t="<<
            _influenceTangential<<" a="<<_influenceAttraction<<" v="<<_influenceVelocity<<" kweight="<<_kernelWeight, 7);
    if(_kernelWeight<=0.) {
        errMsg("ControlParticles::calculateKernelWeight", "invalid kernel! "<<_kernelWeight<<", resetting");
        _kernelWeight = 1.;
    }
}

void 
ControlParticles::prepareControl(LbmFloat simtime, LbmFloat dt, ControlParticles *motion) {
    debMsgStd("ControlParticle::prepareControl",DM_MSG," simtime="<<simtime<<" dt="<<dt<<" ", 5);

    //fprintf(stdout,"PREPARE \n");
    LbmFloat avgdw = 0.;
    for(size_t i=0; i<_particles.size(); i++) {
        ControlParticle *cp = &_particles[i];

        if(this->getInfluenceAttraction()<0.) {
            cp->density= 
            cp->densityWeight = 1.0;
            continue;
        } 

        // normalize by kernel 
        //cp->densityWeight = (1.0 - (cp->density / _kernelWeight)); // store last
#if (CP_PROJECT2D==1) && (defined(MAIN_2D) || LBMDIM==2)
        cp->densityWeight = (1.0 - (cp->density / (_kernelWeight*cp->size*cp->size) )); // store last
#else // 2D
        cp->densityWeight = (1.0 - (cp->density / (_kernelWeight*cp->size*cp->size*cp->size) )); // store last
#endif // MAIN_2D

        if(i<10) debMsgStd("ControlParticle::prepareControl",DM_MSG,"kernelDebug i="<<i<<" densWei="<<cp->densityWeight<<" 1/kw"<<(1.0/_kernelWeight)<<" cpdensity="<<cp->density, 9 );
        if(cp->densityWeight<0.) cp->densityWeight=0.;
        if(cp->densityWeight>1.) cp->densityWeight=1.;
        
        avgdw += cp->densityWeight;
        // reset for next step
        cp->density = 0.; 

        if(cp->avgVelWeight>0.) {
         cp->avgVel = cp->avgVelAcc/cp->avgVelWeight; 
         cp->avgVelWeight   = 0.; 
         cp->avgVelAcc  = LbmVec(0.,0.,0.); 
        }
    }
    //if(debugKernel) for(size_t i=0; i<_particles.size(); i++) { ControlParticle *cp = &_particles[i]; fprintf(stdout,"A %f,%f \n",cp->density,cp->densityWeight); }
    avgdw /= (LbmFloat)(_particles.size());
    //if(motion) { printf("ControlParticle::kernel: avgdw:%f,  kw%f, sp%f \n", avgdw, _kernelWeight, _fluidSpacing); }
    
    //if((simtime>=0.) && (simtime != _currTime)) 
    initTime(simtime, dt);

    if((motion) && (motion->getSize()>0)){
        ControlParticle *motionp = motion->getParticle(0);
        //printf("ControlParticle::prepareControl motion: pos[%f,%f,%f] vel[%f,%f,%f] \n", motionp->pos[0], motionp->pos[1], motionp->pos[2], motionp->vel[0], motionp->vel[1], motionp->vel[2] );
        for(size_t i=0; i<_particles.size(); i++) {
            ControlParticle *cp = &_particles[i];
            cp->pos = cp->pos + motionp->pos;
            cp->vel = cp->vel + motionp->vel;
            cp->size = cp->size * motionp->size;
            cp->influence = cp->size * motionp->influence;
        }
    }
    
    // reset to radiusAtt by default
    if(_radiusVel==0.) _radiusVel = _radiusAtt;
    if(_radiusMinMaxd==0.) _radiusMinMaxd = _radiusAtt;
    if(_radiusMaxd==0.) _radiusMaxd = 2.*_radiusAtt;
    // has to be radiusVel<radiusAtt<radiusMinMaxd<radiusMaxd
    if(_radiusVel>_radiusAtt) _radiusVel = _radiusAtt;
    if(_radiusAtt>_radiusMinMaxd) _radiusAtt = _radiusMinMaxd;
    if(_radiusMinMaxd>_radiusMaxd) _radiusMinMaxd = _radiusMaxd;

    //printf("ControlParticle::radii vel:%f att:%f min:%f max:%f \n", _radiusVel,_radiusAtt,_radiusMinMaxd,_radiusMaxd);
    // prepareControl done
}

void ControlParticles::finishControl(std::vector<ControlForces> &forces, LbmFloat iatt, LbmFloat ivel, LbmFloat imaxd) {

    //const LbmFloat iatt  = this->getInfluenceAttraction() * this->getCurrTimestep();
    //const LbmFloat ivel  = this->getInfluenceVelocity();
    //const LbmFloat imaxd = this->getInfluenceMaxdist() * this->getCurrTimestep();
    // prepare for usage
    iatt  *= this->getCurrTimestep();
    ivel  *= 1.; // not necessary!
    imaxd *= this->getCurrTimestep();

    // skip when size=0
    for(int i=0; i<(int)forces.size(); i++) {
        if(DEBUG_MODVEL) fprintf(stdout, "CPFORGF %d , wf:%f,f:%f,%f,%f  ,  v:%f,%f,%f   \n",i, forces[i].weightAtt, forces[i].forceAtt[0],forces[i].forceAtt[1],forces[i].forceAtt[2],   forces[i].forceVel[0], forces[i].forceVel[1], forces[i].forceVel[2] );
        LbmFloat cfweight = forces[i].weightAtt; // always normalize
        if((cfweight!=0.)&&(iatt!=0.)) {
            // multiple kernels, normalize - note this does not normalize in d>r/2 region
            if(ABS(cfweight)>1.) { cfweight = 1.0/cfweight; }
            // multiply iatt afterwards to allow stronger force
            cfweight *= iatt;
            forces[i].forceAtt *= cfweight;
        } else {
            forces[i].weightAtt =  0.;
            forces[i].forceAtt = LbmVec(0.);
        }

        if( (cfweight==0.) && (imaxd>0.) && (forces[i].maxDistance>0.) ) {
            forces[i].forceMaxd *= imaxd;
        } else {
            forces[i].maxDistance=  0.;
            forces[i].forceMaxd = LbmVec(0.);
        }

        LbmFloat cvweight = forces[i].weightVel; // always normalize
        if(cvweight>0.) {
            forces[i].forceVel /= cvweight;
            forces[i].compAv /= cvweight;
            // now modify cvweight, and write back
            // important, cut at 1 - otherwise strong vel. influences...
            if(cvweight>1.) { cvweight = 1.; }
            // thus cvweight is in the range of 0..influenceVelocity, currently not normalized by numCParts
            cvweight *= ivel;
            if(cvweight<0.) cvweight=0.; if(cvweight>1.) cvweight=1.;
            // LBM, FIXME todo use relaxation factor
            //pvel = (cvel*0.5 * cvweight) + (pvel * (1.0-cvweight)); 
            forces[i].weightVel = cvweight;

            //errMsg("COMPAV","i"<<i<<" compav"<<forces[i].compAv<<" forcevel"<<forces[i].forceVel<<" ");
        } else {
            forces[i].weightVel = 0.;
            if(forces[i].maxDistance==0.) forces[i].forceVel = LbmVec(0.);
            forces[i].compAvWeight = 0.;
            forces[i].compAv = LbmVec(0.);
        }
        if(DEBUG_MODVEL) fprintf(stdout, "CPFINIF %d , wf:%f,f:%f,%f,%f  ,  v:%f,%f,%f   \n",i, forces[i].weightAtt, forces[i].forceAtt[0],forces[i].forceAtt[1],forces[i].forceAtt[2],  forces[i].forceVel[0],forces[i].forceVel[1],forces[i].forceVel[2] );
    }

    // unused...
    if(DEBUG_MODVEL) fprintf(stdout,"MFC iatt:%f,%f ivel:%f,%f ifmd:%f,%f \n", iatt,_radiusAtt, ivel,_radiusVel, imaxd, _radiusMaxd);
    //for(size_t i=0; i<_particles.size(); i++) { ControlParticle *cp = &_particles[i]; fprintf(stdout," %f,%f,%f ",cp->density,cp->densityWeight, (1.0 - (12.0*cp->densityWeight))); }
    //fprintf(stdout,"\n\nCP DONE \n\n\n");
}


// --------------------------------------------------------------------------
// calculate forces at given position, and modify velocity
// according to timestep
void ControlParticles::calculateCpInfluenceOpt(ControlParticle *cp, LbmVec fluidpos, LbmVec fluidvel, ControlForces *force, LbmFloat fillFactor) {
    // dont reset, only add...
    // test distance, simple squared distance reject
    const LbmFloat cpfo = _radiusAtt*cp->size;

    LbmVec posDelta;
    if(DEBUG_MODVEL) fprintf(stdout, "CP at %f,%f,%f bef fw:%f, f:%f,%f,%f  , vw:%f, v:%f,%f,%f   \n",fluidpos[0],fluidpos[1],fluidpos[2], force->weightAtt, force->forceAtt[0], force->forceAtt[1], force->forceAtt[2], force->weightVel, force->forceVel[0], force->forceVel[1], force->forceVel[2]);
    posDelta    = cp->pos - fluidpos;
#if LBMDIM==2 && (CP_PROJECT2D==1)
    posDelta[2] = 0.; // project to xy plane, z-velocity should already be gone...
#endif

    const LbmFloat distsqr = posDelta[0]*posDelta[0]+posDelta[1]*posDelta[1]+posDelta[2]*posDelta[2];
    if(DEBUG_MODVEL) fprintf(stdout, " Pd at %f,%f,%f d%f   \n",posDelta[0],posDelta[1],posDelta[2], distsqr);
    // cut at influence=0.5 , scaling not really makes sense
    if(cpfo*cpfo < distsqr) {
        /*if(cp->influence>0.5) {
            if(force->weightAtt == 0.) {
                if(force->maxDistance*force->maxDistance > distsqr) {
                const LbmFloat dis = sqrtf((float)distsqr);
                const LbmFloat sc = dis-cpfo;
                force->maxDistance = dis;
                force->forceMaxd = (posDelta)*(sc/dis);
                }
            } } */
        return;
    }
    force->weightAtt += 1e-6; // for distance
    force->maxDistance = 0.; // necessary for SPH?

    const LbmFloat pdistance = MAGNITUDE(posDelta);
    LbmFloat pdistinv = 0.;
    if(ABS(pdistance)>0.) pdistinv = 1./pdistance;
    posDelta *= pdistinv;

    LbmFloat falloffAtt = 0.; //CPKernel::kernel(cpfo * 1.0, pdistance);
    const LbmFloat qac = pdistance / cpfo ;
    if (qac < 1.0){ // return 0.;
        if(qac < 0.5) falloffAtt =  1.0f;
        else         falloffAtt = (1.0f - qac) * 2.0f;
    }

    // vorticity force:
    // - //LbmVec forceVort; 
    // - //CROSS(forceVort, posDelta, cp->rotaxis);
    // - //NORMALIZE(forceVort);
    // - if(falloffAtt>1.0) falloffAtt=1.0;

#if (CP_PROJECT2D==1) && (defined(MAIN_2D) || LBMDIM==2)
    // fillFactor *= 2.0 *0.75 * pdistance; // 2d>3d sampling
#endif // (CP_PROJECT2D==1) && (defined(MAIN_2D) || LBMDIM==2)
    
    LbmFloat signum = getInfluenceAttraction() > 0.0 ? 1.0 : -1.0;  
    cp->density += falloffAtt * fillFactor;
    force->forceAtt +=  posDelta *cp->densityWeight *cp->influence *signum; 
    force->weightAtt += falloffAtt*cp->densityWeight *cp->influence;
    
    LbmFloat falloffVel = 0.; //CPKernel::kernel(cpfo * 1.0, pdistance);
    const LbmFloat cpfv = _radiusVel*cp->size;
    if(cpfv*cpfv < distsqr) { return; }
    const LbmFloat qvc = pdistance / cpfo ;
    //if (qvc < 1.0){ 
        //if(qvc < 0.5) falloffVel =  1.0f;
        //else         falloffVel = (1.0f - qvc) * 2.0f;
    //}
    falloffVel = 1.-qvc;

    LbmFloat pvWeight; // = (1.0-cp->densityWeight) * _currTimestep * falloffVel;
    pvWeight = falloffVel *cp->influence; // std, without density influence
    //pvWeight *= (1.0-cp->densityWeight); // use inverse density weight
    //pvWeight *=      cp->densityWeight; // test, use density weight
    LbmVec modvel(0.);
    modvel += cp->vel * pvWeight;
    //pvWeight = 1.; modvel = partVel; // DEBUG!?

    if(pvWeight>0.) {
        force->forceVel += modvel;
        force->weightVel += pvWeight;

        cp->avgVelWeight += falloffVel;
        cp->avgVel += fluidvel;
    } 
    if(DEBUG_MODVEL) fprintf(stdout, "CP at %f,%f,%f aft fw:%f, f:%f,%f,%f  , vw:%f, v:%f,%f,%f   \n",fluidpos[0],fluidpos[1],fluidpos[2], force->weightAtt, force->forceAtt[0], force->forceAtt[1], force->forceAtt[2], force->weightVel, force->forceVel[0], force->forceVel[1], force->forceVel[2]);
    return;
}

void ControlParticles::calculateMaxdForce(ControlParticle *cp, LbmVec fluidpos, ControlForces *force) {
    if(force->weightAtt != 0.) return; // maxd force off
    if(cp->influence <= 0.5) return;   // ignore

    LbmVec posDelta;
    //if(DEBUG_MODVEL) fprintf(stdout, "CP at %f,%f,%f bef fw:%f, f:%f,%f,%f  , vw:%f, v:%f,%f,%f   \n",fluidpos[0],fluidpos[1],fluidpos[2], force->weightAtt, force->forceAtt[0], force->forceAtt[1], force->forceAtt[2], force->weightVel, force->forceVel[0], force->forceVel[1], force->forceVel[2]);
    posDelta    = cp->pos - fluidpos;
#if LBMDIM==2 && (CP_PROJECT2D==1)
    posDelta[2] = 0.; // project to xy plane, z-velocity should already be gone...
#endif

    // dont reset, only add...
    // test distance, simple squared distance reject
    const LbmFloat distsqr = posDelta[0]*posDelta[0]+posDelta[1]*posDelta[1]+posDelta[2]*posDelta[2];
    
    // closer cp found
    if(force->maxDistance*force->maxDistance < distsqr) return;
    
    const LbmFloat dmin = _radiusMinMaxd*cp->size;
    if(distsqr<dmin*dmin) return; // inside min
    const LbmFloat dmax = _radiusMaxd*cp->size;
    if(distsqr>dmax*dmax) return; // outside


    if(DEBUG_MODVEL) fprintf(stdout, " Pd at %f,%f,%f d%f   \n",posDelta[0],posDelta[1],posDelta[2], distsqr);
    // cut at influence=0.5 , scaling not really makes sense
    const LbmFloat dis = sqrtf((float)distsqr);
    //const LbmFloat sc = dis - dmin;
    const LbmFloat sc = (dis-dmin)/(dmax-dmin); // scale from 0-1
    force->maxDistance = dis;
    force->forceMaxd = (posDelta/dis) * sc;
    //debug errMsg("calculateMaxdForce","pos"<<fluidpos<<" dis"<<dis<<" sc"<<sc<<" dmin"<<dmin<<" maxd"<< force->maxDistance <<" fmd"<<force->forceMaxd );
    return;
}