grcar.cpp

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/***************************************************************************

    file                 : grcar.cpp
    created              : Mon Aug 21 18:24:02 CEST 2000
    copyright            : (C) 2000 by Eric Espie
    email                : torcs@free.fr
    version              : $Id$

***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/

#include <math.h>
#include <stdlib.h>
#include <sys/types.h>
#include <stdio.h>
#include <ctype.h>
#ifdef WIN32
#include <windows.h>
#endif
#include <GL/glut.h>
#include <plib/ssg.h>

#include <tgfclient.h>
#include <track.h>
#include <car.h>
#include <graphic.h>
#include <robottools.h>
#include <portability.h>

#include "grmain.h"
#include "grshadow.h"
#include "grskidmarks.h"
#include "grsmoke.h"
#include "grcar.h"
#include "grcam.h"
#include "grscene.h"
#include "grboard.h"
#include "grssgext.h"
#include "grutil.h"
#include "grcarlight.h"

extern ssgEntity *grssgLoadAC3D ( const char *fname, const ssgLoaderOptions* options );
extern ssgEntity *grssgCarLoadAC3D ( const char *fname, const ssgLoaderOptions* options,int index );
extern double carTrackRatioX;
extern double carTrackRatioY;

ssgBranch *CarsAnchorTmp = 0;


static int grCarIndex;

static ssgSimpleState *brakeState = NULL;
static ssgSimpleState *commonState = NULL;

void grInitCommonState(void)
{
    // brake
    if (brakeState == NULL) {
        brakeState = new ssgSimpleState;
        brakeState->ref();
        brakeState->disable(GL_LIGHTING);
        brakeState->disable(GL_TEXTURE_2D);
    }

    if (commonState == NULL) {
        commonState = new ssgSimpleState;
        commonState->ref();
        commonState->disable(GL_LIGHTING);
        commonState->disable(GL_TEXTURE_2D);
        commonState->setColourMaterial(GL_AMBIENT_AND_DIFFUSE);
    }
}




static ssgTransform *initWheel(tCarElt *car, int wheel_index)
{
    int     i, j, k;
    float   alpha;
    sgVec3  vtx;
    sgVec4  clr;
    sgVec3  nrm;
    sgVec2  tex;
    tdble   b_offset = 0.0f;
    tdble   curAngle = 0.0f;

#define BRK_BRANCH  16
#define BRK_ANGLE   (2.0 * M_PI / (tdble)BRK_BRANCH)
#define BRK_OFFSET  0.2

    switch(wheel_index) {
        case FRNT_RGT:
            curAngle = -(M_PI / 2.0 + BRK_ANGLE);
            b_offset = BRK_OFFSET - car->_tireWidth(wheel_index) / 2.0;
            break;
        case FRNT_LFT:
            curAngle = -(M_PI / 2.0 + BRK_ANGLE);
            b_offset = car->_tireWidth(wheel_index) / 2.0 - BRK_OFFSET;
            break;
        case REAR_RGT:
            curAngle = (M_PI / 2.0 - BRK_ANGLE);
            b_offset = BRK_OFFSET - car->_tireWidth(wheel_index) / 2.0;
            break;
        case REAR_LFT:
            curAngle = (M_PI / 2.0 - BRK_ANGLE);
            b_offset = car->_tireWidth(wheel_index) / 2.0 - BRK_OFFSET;
            break;
    }

    /* hub */
    ssgVertexArray  *brk_vtx = new ssgVertexArray(BRK_BRANCH + 1);
    ssgColourArray  *brk_clr = new ssgColourArray(1);
    ssgNormalArray  *brk_nrm = new ssgNormalArray(1);
    tdble hubRadius;
    
    /* center */
    vtx[0] = vtx[2] = 0.0;
    vtx[1] = b_offset;
    brk_vtx->add(vtx);
    
    hubRadius = car->_brakeDiskRadius(wheel_index) * 0.6;
    for (i = 0; i < BRK_BRANCH; i++) {
        alpha = (float)i * 2.0 * M_PI / (float)(BRK_BRANCH - 1);
        vtx[0] = hubRadius * cos(alpha);
        vtx[1] = b_offset;
        vtx[2] = hubRadius * sin(alpha);
        brk_vtx->add(vtx);
    }
    

    clr[0] = clr[1] = clr[2] = 0.0;
    clr[3] = 1.0;
    brk_clr->add(clr);
    nrm[0] = nrm[2] = 0.0;

    // Make normal point outside to have proper lighting.
    switch(wheel_index) {
        case FRNT_RGT:
        case REAR_RGT:
            nrm[1] = -1.0;
            break;
        case FRNT_LFT:
        case REAR_LFT:
            nrm[1] = 1.0;
            break;
    }

    brk_nrm->add(nrm);

    ssgVtxTable *brk = new ssgVtxTable(GL_TRIANGLE_FAN, brk_vtx, brk_nrm, NULL, brk_clr);
    brk->setCullFace(0);
    brk->setState(commonState);

    ssgTransform *wheel = new ssgTransform;
    wheel->addKid(brk);

    /* Brake disk */
    brk_vtx = new ssgVertexArray(BRK_BRANCH + 4);
    brk_clr = new ssgColourArray(1);
    brk_nrm = new ssgNormalArray(1);

    for (i = 0; i < (BRK_BRANCH / 2 + 2); i++) {
        alpha = curAngle + (float)i * 2.0 * M_PI / (float)(BRK_BRANCH - 1);
        vtx[0] = car->_brakeDiskRadius(wheel_index) * cos(alpha);
        vtx[1] = b_offset;
        vtx[2] = car->_brakeDiskRadius(wheel_index) * sin(alpha);
        brk_vtx->add(vtx);
        vtx[0] = car->_brakeDiskRadius(wheel_index) * cos(alpha) * 0.6;
        vtx[1] = b_offset;
        vtx[2] = car->_brakeDiskRadius(wheel_index) * sin(alpha) * 0.6;
        brk_vtx->add(vtx);
    }
    

    clr[0] = clr[1] = clr[2] = 0.1;
    clr[3] = 1.0;
    brk_clr->add(clr);
    //nrm[0] = nrm[2] = 0.0;
    //nrm[1] = 1.0;
    brk_nrm->add(nrm);
    
    brk = new ssgVtxTable(GL_TRIANGLE_STRIP, brk_vtx, brk_nrm, NULL, brk_clr);
    brk->setCullFace(0);
    brk->setState(brakeState);
    grCarInfo[grCarIndex].brkColor[wheel_index] = brk_clr;

    wheel->addKid(brk);

    /* Brake caliper */
    brk_vtx = new ssgVertexArray(BRK_BRANCH - 4);
    brk_clr = new ssgColourArray(1);
    brk_nrm = new ssgNormalArray(1);

    for (i = 0; i < (BRK_BRANCH / 2 - 2); i++) {
        alpha = - curAngle + (float)i * 2.0 * M_PI / (float)(BRK_BRANCH - 1);
        vtx[0] = (car->_brakeDiskRadius(wheel_index) + 0.02) * cos(alpha);
        vtx[1] = b_offset;
        vtx[2] = (car->_brakeDiskRadius(wheel_index) + 0.02) * sin(alpha);
        brk_vtx->add(vtx);
        vtx[0] = car->_brakeDiskRadius(wheel_index) * cos(alpha) * 0.6;
        vtx[1] = b_offset;
        vtx[2] = car->_brakeDiskRadius(wheel_index) * sin(alpha) * 0.6;
        brk_vtx->add(vtx);
    }
    

    clr[0] = 0.2;
    clr[1] = 0.2;
    clr[2] = 0.2;
    clr[3] = 1.0;
    brk_clr->add(clr);
    //nrm[0] = nrm[2] = 0.0;
    //nrm[1] = 1.0;
    brk_nrm->add(nrm);

    brk = new ssgVtxTable(GL_TRIANGLE_STRIP, brk_vtx, brk_nrm, NULL, brk_clr);
    brk->setCullFace(0);
    brk->setState(commonState);

    wheel->addKid(brk);

    DBG_SET_NAME(wheel, "Wheel", grCarIndex, wheel_index);

    grCarInfo[grCarIndex].wheelPos[wheel_index] = wheel;

    /* wheels */
    ssgTransform *whrotation = new ssgTransform;
    grCarInfo[grCarIndex].wheelRot[wheel_index] = whrotation;
    wheel->addKid(whrotation);
    ssgSelector *whselector = new ssgSelector;
    whrotation->addKid(whselector);
    grCarInfo[grCarIndex].wheelselector[wheel_index] = whselector;

    float   wheelRadius = car->_rimRadius(wheel_index) + car->_tireHeight(wheel_index);

    // Create wheels for 4 speeds (stillstanding - fast --> motion blur, look at the texture).
    for (j = 0; j < 4; j++) {
        ssgBranch *whl_branch = new ssgBranch;
        ssgEntity *whl3d = 0;

        // load speed-dependant 3D wheels if available and if detailed wheels are desired.
        // wheel data files are located in the wheels directory. first set directory.
        if (grUseDetailedWheels == DETAILED) {
            const int bufsize = 1024;
            char buf[bufsize];
            const char* wheel_dir = GfParmGetStr(car->_carHandle, SECT_GROBJECTS, PRM_WHEEL_3D_DIR, 0);
            if (wheel_dir != 0) {
                snprintf(buf, bufsize, "wheels/%s", wheel_dir);
                ssgModelPath(buf);
                ssgTexturePath(buf);
            }
            
            // set basename for wheel file 0..3 gets appended
            const char* wheel_obj = GfParmGetStr(car->_carHandle, SECT_GROBJECTS, PRM_WHEEL_3D, 0);
            if (wheel_obj != 0 && wheel_dir != 0) {
                snprintf(buf, bufsize, "%s%d.acc", wheel_obj, j);
                whl3d = grssgCarLoadAC3D(buf, NULL, car->index);
            }
        }
        
        // if we have a 3D wheel, use it.  otherwise use normal generated wheel...
        if (whl3d) {
            // Adapt size of the wheel
            ssgTransform *whl_size = new ssgTransform;
            sgMat4 wheelsz;

            sgSetVec4(wheelsz[0], wheelRadius * 2, SG_ZERO, SG_ZERO, SG_ZERO) ;
            sgSetVec4(wheelsz[1], SG_ZERO, car->_tireWidth(wheel_index), SG_ZERO, SG_ZERO) ;
            sgSetVec4(wheelsz[2], SG_ZERO, SG_ZERO, wheelRadius * 2, SG_ZERO) ;
            sgSetVec4(wheelsz[3], SG_ZERO, SG_ZERO, SG_ZERO, SG_ONE) ;

            whl_size->setTransform(wheelsz);

            whl_size->addKid(whl3d);
            whl3d = whl_size;

            if (wheel_index == FRNT_RGT || wheel_index == REAR_RGT) {
                // flip wheel around so it faces the right way
                ssgTransform *whl_mesh_transform = new ssgTransform;
                sgCoord wheelpos;
                sgSetCoord(&wheelpos, 0, 0, 0, 180, 0, 0);
                whl_mesh_transform->setTransform( &wheelpos);
                whl_mesh_transform->addKid(whl3d);
                whl_branch->addKid(whl_mesh_transform);
            } else {
                whl_branch->addKid(whl3d);
            }
        } else {
            static sgVec2   toffset[4] = { {0.0, 0.5}, {0.5, 0.5}, {0.0, 0.0}, {0.5, 0.0} };
            // TORCS's standard generated wheel
            const int WHL_BRANCH = 16;

            /* Tread */
            {
                ssgVertexArray  *whl_vtx = new ssgVertexArray(2 * WHL_BRANCH);
                ssgColourArray  *whl_clr = new ssgColourArray(2 * WHL_BRANCH);
                ssgNormalArray  *whl_nrm = new ssgNormalArray(1);

                whl_nrm->add(nrm);
                clr[3] = 1.0;
                for (i = 0; i < WHL_BRANCH; i++) {
                    alpha = (float)i * 2.0 * M_PI / (float)(WHL_BRANCH - 1);
                    vtx[0] = wheelRadius * cos(alpha);
                    vtx[2] = wheelRadius * sin(alpha);
                    vtx[1] = - car->_tireWidth(wheel_index) / 2.0;
                    whl_vtx->add(vtx);
                    vtx[1] = car->_tireWidth(wheel_index) / 2.0;
                    whl_vtx->add(vtx);
                    if (i % 2) {
                        clr[0] = clr[1] = clr[2] = 0.15;
                    } else {
                        clr[0] = clr[1] = clr[2] = 0.0;
                    }
                    whl_clr->add(clr);
                    whl_clr->add(clr);
                }
                ssgVtxTable *whl = new ssgVtxTable(GL_TRIANGLE_STRIP, whl_vtx, whl_nrm, NULL, whl_clr);
                whl->setState(commonState);
                whl->setCullFace(0);

                    // stripify wheel, should improve performance
                    ssgStripify(whl);

                whl_branch->addKid(whl);
            }

            /* Rim */
            switch(wheel_index) {
                case FRNT_RGT:
                case REAR_RGT:
                    b_offset = -0.05;
                    break;
                case FRNT_LFT:
                case REAR_LFT:
                    b_offset = 0.05;
                    break;
            }

            // Make inside rim very dark and take care of normals.
            float colorfactor[2];
            float norm_orig = nrm[1];

            if (nrm[1] > 0.0f) {
                colorfactor[0] = 0.3f;
                colorfactor[1] = 1.0f;
                nrm[1] *= -1.0f;
            } else {
                colorfactor[0] = 1.0f;
                colorfactor[1] = 0.3f;
            }

            for (k = 0; k < 2; k++) {
                ssgVertexArray  *whl_vtx = new ssgVertexArray(WHL_BRANCH + 1);
                ssgTexCoordArray    *whl_tex = new ssgTexCoordArray(WHL_BRANCH + 1);
                ssgColourArray  *whl_clr = new ssgColourArray(1);
                ssgNormalArray  *whl_nrm = new ssgNormalArray(1);

                clr[0] = 0.8f*colorfactor[k];
                clr[1] = 0.8f*colorfactor[k];
                clr[2] = 0.8f*colorfactor[k];
                clr[3] = 1.0f;

                whl_clr->add(clr);
                whl_nrm->add(nrm);
                vtx[0] = vtx[2] = 0.0;
                vtx[1] = (float)(2 * k - 1) * car->_tireWidth(wheel_index) / 2.0 - b_offset;
                whl_vtx->add(vtx);
                tex[0] = 0.25 + toffset[j][0];
                tex[1] = 0.25 + toffset[j][1];
                whl_tex->add(tex);
                vtx[1] = (float)(2 * k - 1) * car->_tireWidth(wheel_index) / 2.0;
                for (i = 0; i < WHL_BRANCH; i++) {
                    alpha = (float)i * 2.0 * M_PI / (float)(WHL_BRANCH - 1);
                    vtx[0] = wheelRadius * cos(alpha);
                    vtx[2] = wheelRadius * sin(alpha);
                    whl_vtx->add(vtx);
                    tex[0] = 0.25 + 0.25 * cos(alpha) + toffset[j][0];
                    tex[1] = 0.25 + 0.25 * sin(alpha) + toffset[j][1];
                    whl_tex->add(tex);
                }
                ssgVtxTable *whl = new ssgVtxTable(GL_TRIANGLE_FAN, whl_vtx, whl_nrm, whl_tex, whl_clr);
                whl->setState(grCarInfo[grCarIndex].wheelTexture);
                whl->setCullFace(0);

                    // stripify rim, should improve performance
                    ssgStripify(whl);

                whl_branch->addKid(whl);

                // Swap normal for "inside" rim face.
                nrm[1] *= -1.0;
            }

            nrm[1] = norm_orig;
        }

        whselector->addKid(whl_branch);
    }
    
    return wheel;
}


static const int GR_SHADOW_POINTS = 6;

void grInitShadow(tCarElt *car)
{
    const int BUFSIZE = 256;
    char        buf[BUFSIZE];
    const char  *shdTexName;
    int         i;
    float       x;
    sgVec3      vtx;
    sgVec4      clr;
    sgVec3      nrm;
    sgVec2      tex;
    ssgVertexArray  *shd_vtx = new ssgVertexArray(GR_SHADOW_POINTS+1);
    ssgColourArray  *shd_clr = new ssgColourArray(1);
    ssgNormalArray  *shd_nrm = new ssgNormalArray(1);
    ssgTexCoordArray    *shd_tex = new ssgTexCoordArray(GR_SHADOW_POINTS+1);

    snprintf(buf, BUFSIZE, "cars/%s;", car->_carName);
    grFilePath = buf;

    shdTexName = GfParmGetStr(car->_carHandle, SECT_GROBJECTS, PRM_SHADOW_TEXTURE, "");

    grCarInfo[car->index].shadowAnchor = new ssgBranch();

    clr[0] = clr[1] = clr[2] = 1.0;
    clr[3] = 1.0;
    shd_clr->add(clr);
    nrm[0] = nrm[1] = 0.0;
    nrm[2] = 1.0;
    shd_nrm->add(nrm);

    /* vertices */
#define MULT    1.1
    vtx[2] = 0.0;
    for (i = 0, x = car->_dimension_x * MULT / 2.0; i < GR_SHADOW_POINTS / 2; i++, x -= car->_dimension_x * MULT / (float)(GR_SHADOW_POINTS - 2) * 2.0) {
        vtx[0] = x;
        tex[0] = 1.0 - (float)i / (float)((GR_SHADOW_POINTS - 2) / 2.0);

        vtx[1] = -car->_dimension_y * MULT / 2.0;
        shd_vtx->add(vtx);
        tex[1] = 0.0;
        shd_tex->add(tex);

        vtx[1] = car->_dimension_y * MULT / 2.0;
        shd_vtx->add(vtx);
        tex[1] = 1.0;
        shd_tex->add(tex);

    };

    grCarInfo[car->index].shadowBase = new ssgVtxTableShadow(GL_TRIANGLE_STRIP, shd_vtx, shd_nrm, shd_tex, shd_clr);
    grMipMap = 0;
    grCarInfo[car->index].shadowBase->setState(grSsgLoadTexState(shdTexName));
    grCarInfo[car->index].shadowCurr = (ssgVtxTableShadow *)grCarInfo[car->index].shadowBase->clone(SSG_CLONE_GEOMETRY);
    grCarInfo[car->index].shadowAnchor->addKid(grCarInfo[car->index].shadowCurr);
    ShadowAnchor->addKid(grCarInfo[car->index].shadowAnchor);
    grCarInfo[car->index].shadowBase->ref();
}




void grPropagateDamage (ssgEntity* l, sgVec3 poc, sgVec3 force, int cnt)
{
    //showEntityType (l);
    if (l->isAKindOf (ssgTypeBranch())) {
        
        ssgBranch* br = (ssgBranch*) l;

        for (int i = 0 ; i < br -> getNumKids () ; i++ ) {
            ssgEntity* ln = br->getKid (i);
            grPropagateDamage(ln, poc, force, cnt+1);
        }
    }
    
    if (l->isAKindOf (ssgTypeVtxTable())) {
        sgVec3* v;
        int Nv;
        ssgVtxTable* vt = (ssgVtxTable*) l;
        Nv = vt->getNumVertices();
        vt->getVertexList ((void**) &v);
        tdble sigma = sgLengthVec3 (force);
        tdble invSigma = 5.0;

        for (int i=0; i<Nv; i++) {
            tdble r =  sgDistanceSquaredVec3 (poc, v[i]);
            tdble f = exp(-r*invSigma)*5.0;
            v[i][0] += force[0]*f;
            v[i][1] += force[1]*f;
            // use sigma as a random number generator (!)
            v[i][2] += (force[2]+0.02*sin(2.0*r + 10.0*sigma))*f;
            //printf ("(%f %f %f)\n", v[i][0], v[i][1], v[i][2]);
        }
    }
}


void 
grInitCar(tCarElt *car)
{
    const int BUFSIZE=4096;
    char buf[BUFSIZE];
    int index;
    int selIndex;
    ssgEntity *carEntity;
    ssgSelector *LODSel;
    ssgTransform *wheel[4];
    int nranges;
    int i, j;
    void *handle;
    const char *param;
    int lg;
    const int PATHSIZE=256;
    char path[PATHSIZE];
    myLoaderOptions options;
    sgVec3 lightPos;
    int lightNum;
    const char *lightType;
    int lightTypeNum;


    if (!CarsAnchorTmp) {
        CarsAnchorTmp = new ssgBranch();
    }

    grInitBoardCar(car);

    TRACE_GL("loadcar: start");

    ssgSetCurrentOptions ( &options ) ;

    grCarIndex = index = car->index;    /* current car's index */
    handle = car->_carHandle;

    /* Load visual attributes */
    car->_exhaustNb = GfParmGetEltNb(handle, SECT_EXHAUST);
    car->_exhaustNb = MIN(car->_exhaustNb, 2);
    car->_exhaustPower = GfParmGetNum(handle, SECT_EXHAUST, PRM_POWER, NULL, 1.0);
    for (i = 0; i < car->_exhaustNb; i++) {
        snprintf(path, PATHSIZE, "%s/%d", SECT_EXHAUST, i + 1);
        car->_exhaustPos[i].x = GfParmGetNum(handle, path, PRM_XPOS, NULL, -car->_dimension_x / 2.0);
        car->_exhaustPos[i].y = -GfParmGetNum(handle, path, PRM_YPOS, NULL, car->_dimension_y / 2.0);
        car->_exhaustPos[i].z = GfParmGetNum(handle, path, PRM_ZPOS, NULL, 0.1);
    }

    snprintf(path, PATHSIZE, "%s/%s", SECT_GROBJECTS, SECT_LIGHT);
    lightNum = GfParmGetEltNb(handle, path);
    for (i = 0; i < lightNum; i++) {
        snprintf(path, PATHSIZE, "%s/%s/%d", SECT_GROBJECTS, SECT_LIGHT, i + 1);
        lightPos[0] = GfParmGetNum(handle, path, PRM_XPOS, NULL, 0);
        lightPos[1] = GfParmGetNum(handle, path, PRM_YPOS, NULL, 0);
        lightPos[2] = GfParmGetNum(handle, path, PRM_ZPOS, NULL, 0);
        lightType = GfParmGetStr(handle, path, PRM_TYPE, "");
        lightTypeNum = LIGHT_NO_TYPE;
        if (!strcmp(lightType, VAL_LIGHT_HEAD1)) {
            lightTypeNum = LIGHT_TYPE_FRONT;
        } else if (!strcmp(lightType, VAL_LIGHT_HEAD2)) {
            lightTypeNum = LIGHT_TYPE_FRONT2;
        } else if (!strcmp(lightType, VAL_LIGHT_BRAKE)) {
            lightTypeNum = LIGHT_TYPE_BRAKE;
        } else if (!strcmp(lightType, VAL_LIGHT_BRAKE2)) {
            lightTypeNum = LIGHT_TYPE_BRAKE2;
        } else if (!strcmp(lightType, VAL_LIGHT_REAR)) {
            lightTypeNum = LIGHT_TYPE_REAR;
        }
        grAddCarlight(car, lightTypeNum, lightPos, GfParmGetNum(handle, path, PRM_SIZE, NULL, 0.2));
    }

    grLinkCarlights(car);


    GfOut("[gr] Init(%d) car %s for driver %s index %d\n", index, car->_carName, car->_modName, car->_driverIndex);

    grFilePath = (char*)malloc(BUFSIZE);
    lg = 0;
    lg += snprintf(grFilePath + lg, BUFSIZE - lg, "drivers/%s/%d/%s;", car->_modName, car->_driverIndex, car->_carName);
    lg += snprintf(grFilePath + lg, BUFSIZE - lg, "drivers/%s/%d;", car->_modName, car->_driverIndex);
    lg += snprintf(grFilePath + lg, BUFSIZE - lg, "drivers/%s/%s;", car->_modName, car->_carName);
    lg += snprintf(grFilePath + lg, BUFSIZE - lg, "drivers/%s;", car->_modName);
    lg += snprintf(grFilePath + lg, BUFSIZE - lg, "cars/%s", car->_carName);

    param = GfParmGetStr(handle, SECT_GROBJECTS, PRM_WHEEL_TEXTURE, "");
    if (strlen(param) != 0) {
        grGammaValue = 1.8;
        grMipMap = 0;
        grCarInfo[index].wheelTexture = grSsgLoadTexState(param);
        grCarInfo[index].wheelTexture->ref();
    }
    
    grCarInfo[index].envSelector = (ssgStateSelector*)grEnvSelector->clone();
    grCarInfo[index].envSelector->ref();

    /* the base transformation of the car (rotation + translation) */
    grCarInfo[index].carTransform = new ssgTransform;
    DBG_SET_NAME(grCarInfo[index].carTransform, car->_modName, index, -1);

    /* Level of details */
    grCarInfo[index].LODSelector = LODSel = new ssgSelector;
    grCarInfo[index].carTransform->addKid(LODSel);
    snprintf(path, PATHSIZE, "%s/%s", SECT_GROBJECTS, LST_RANGES);
    nranges = GfParmGetEltNb(handle, path) + 1;
    if (nranges < 2) {
        GfOut("Error not enough levels of detail\n");
        FREEZ(grFilePath);
        return;
    }

    /* First LOD */
    ssgBranch *carBody = new ssgBranch;
    DBG_SET_NAME(carBody, "LOD", index, 0);
    LODSel->addKid(carBody);

    /* The car's model is under cars/<model> */
    snprintf(buf, BUFSIZE, "cars/%s", car->_carName);
    ssgModelPath(buf);
    snprintf(buf, BUFSIZE, "drivers/%s/%d;drivers/%s;cars/%s", car->_modName, car->_driverIndex, car->_modName, car->_carName);
    ssgTexturePath(buf);
    grTexturePath = strdup(buf);

    /* loading raw car level 0*/
    selIndex = 0;   /* current selector index */
    snprintf(buf, BUFSIZE, "%s.ac", car->_carName); /* default car name */
    snprintf(path, PATHSIZE, "%s/%s/1", SECT_GROBJECTS, LST_RANGES);
    param = GfParmGetStr(handle, path, PRM_CAR, buf);
    grCarInfo[index].LODThreshold[selIndex] = GfParmGetNum(handle, path, PRM_THRESHOLD, NULL, 0.0);
    /*carEntity = ssgLoad(param);*/
    carEntity = grssgCarLoadAC3D(param, NULL, index);
    grCarInfo[index].carEntity = carEntity;

    /* Set a selector on the driver */
    char* stmp = strdup("DRIVER");
    ssgBranch *b = (ssgBranch *)carEntity->getByName(stmp);
    free(stmp);

    grCarInfo[index].driverSelector = new ssgSelector;
    if (b) {
        ssgBranch *bp = b->getParent(0);
        bp->addKid(grCarInfo[index].driverSelector);
        grCarInfo[index].driverSelector->addKid(b);
        bp->removeKid(b);
        grCarInfo[index].driverSelector->select(1);
        grCarInfo[index].driverSelectorinsg = true;
    } else {
        grCarInfo[index].driverSelectorinsg = false;
    }


    DBG_SET_NAME(carEntity, "Body", index, -1);
    carBody->addKid(carEntity);
    /* add wheels */
    for (i = 0; i < 4; i++){
        wheel[i] = initWheel(car, i);
        carBody->addKid(wheel[i]);
    }
    grCarInfo[index].LODSelectMask[0] = 1 << selIndex; /* car mask */
    selIndex++;
    grCarInfo[index].sx=carTrackRatioX;
    grCarInfo[index].sy=carTrackRatioY;

    /* Other LODs */
    for (i = 2; i < nranges; i++) {
        carBody = new ssgBranch;
        snprintf(buf, BUFSIZE, "%s/%s/%d", SECT_GROBJECTS, LST_RANGES, i);
        param = GfParmGetStr(handle, buf, PRM_CAR, "");
        grCarInfo[index].LODThreshold[selIndex] = GfParmGetNum(handle, buf, PRM_THRESHOLD, NULL, 0.0);
        /* carEntity = ssgLoad(param); */
        carEntity = grssgCarLoadAC3D(param, NULL, index);;
        DBG_SET_NAME(carEntity, "LOD", index, i-1);
        carBody->addKid(carEntity);
        if (!strcmp(GfParmGetStr(handle, buf, PRM_WHEELSON, "no"), "yes")) {
            /* add wheels */
            for (j = 0; j < 4; j++){
                carBody->addKid(wheel[j]);
            }
        }
        LODSel->addKid(carBody);
        grCarInfo[index].LODSelectMask[i-1] = 1 << selIndex; /* car mask */
        selIndex++;
    }
    /* default range selection */
    LODSel->select(grCarInfo[index].LODSelectMask[0]);

    CarsAnchor->addKid(grCarInfo[index].carTransform);
    
    //grCarInfo[index].carTransform->print(stdout, "-", 1);

    FREEZ(grTexturePath);
    FREEZ(grFilePath);
    options.endLoad();

    TRACE_GL("loadcar: end");
}

static void
grDrawShadow(tCarElt *car, int visible)
{
    int     i;
    ssgVtxTableShadow   *shadow;
    sgVec3  *vtx;

    if (grCarInfo[car->index].shadowAnchor->getNumKids() != 0) {
        grCarInfo[car->index].shadowAnchor->removeKid(grCarInfo[car->index].shadowCurr);
    }

    if (visible) {
        shadow = (ssgVtxTableShadow *)grCarInfo[car->index].shadowBase->clone(SSG_CLONE_GEOMETRY);
        /* shadow->setState(shadowState); */
        shadow->setCullFace(TRUE);
        shadow->getVertexList((void**)&vtx);

        shadow->transform(grCarInfo[car->index].carPos);

        for (i = 0; i < GR_SHADOW_POINTS; i++) {
            vtx[i][2] = RtTrackHeightG(car->_trkPos.seg, vtx[i][0], vtx[i][1]) + 0.00;
        }

        grCarInfo[car->index].shadowCurr = shadow;
        grCarInfo[car->index].shadowAnchor->addKid(shadow);
    }
}




tdble grGetDistToStart(tCarElt *car)
{
    tTrackSeg *seg;
    tdble lg;

    seg = car->_trkPos.seg;
    lg = seg->lgfromstart;

    switch (seg->type) {
        case TR_STR:
            lg += car->_trkPos.toStart;
            break;
        default:
            lg += car->_trkPos.toStart * seg->radius;
            break;
    }
    return lg;
}




void grDrawCar(tCarElt *car, tCarElt *curCar, int dispCarFlag, int dispDrvFlag, double curTime, class cGrPerspCamera *curCam)
{
    sgCoord wheelpos;
    int index, i, j;
    static float maxVel[3] = { 20.0, 40.0, 70.0 };
    float lod;

    TRACE_GL("cggrDrawCar: start");

    index = car->index;
    if (car->priv.collision_state.collision_count > 0) {
        tCollisionState* collision_state = &car->priv.collision_state;
        grPropagateDamage (grCarInfo[index].carEntity, collision_state->pos, collision_state->force, 0);
        collision_state->collision_count = 0;
    }
    
    grCarInfo[index].distFromStart=grGetDistToStart(car);
    grCarInfo[index].envAngle=RAD2DEG(car->_yaw);

    if ((car == curCar) && (dispCarFlag != 1)) {
        grCarInfo[index].LODSelector->select(0);
    } else {
        lod = curCam->getLODFactor(car->_pos_X, car->_pos_Y, car->_pos_Z);
        i = 0;
        while (lod < grCarInfo[index].LODThreshold[i] * grLodFactorValue) {
            i++;
        }
        if ((car->_state & RM_CAR_STATE_DNF) && (grCarInfo[index].LODThreshold[i] > 0.0)) {
            i++;
        }
        grCarInfo[index].LODSelector->select(grCarInfo[index].LODSelectMask[i]);
        if (dispDrvFlag) {
            grCarInfo[index].driverSelector->select(1);
        } else {
            grCarInfo[index].driverSelector->select(0);
        }
    }

    sgCopyMat4(grCarInfo[index].carPos, car->_posMat);
    grCarInfo[index].px=car->_pos_X;
    grCarInfo[index].py=car->_pos_Y;

    grCarInfo[index].carTransform->setTransform(grCarInfo[index].carPos);

    if ((car == curCar) && (dispCarFlag != 1)) {
        grDrawShadow(car, 0);
    } else {
        grDrawShadow(car, 1);
    }
    
    grUpdateSkidmarks(car, curTime); 
    grDrawSkidmarks(car);
    grAddSmoke(car, curTime);
    
    if ((car == curCar) && (dispCarFlag != 1)) {
        grUpdateCarlight(car, curCam, 0);
    } else {
        grUpdateCarlight(car, curCam, 1);
    }

    /* Env mapping selection by the position on the track */
    grCarInfo[index].envSelector->selectStep(car->_trkPos.seg->envIndex);

    /* wheels */
    for (i = 0; i < 4; i++) {
        float   *clr;

        sgSetCoord(&wheelpos, car->priv.wheel[i].relPos.x, car->priv.wheel[i].relPos.y, car->priv.wheel[i].relPos.z,
                    RAD2DEG(car->priv.wheel[i].relPos.az), RAD2DEG(car->priv.wheel[i].relPos.ax), 0);
        grCarInfo[index].wheelPos[i]->setTransform(&wheelpos);
        sgSetCoord(&wheelpos, 0, 0, 0, 0, 0, RAD2DEG(car->priv.wheel[i].relPos.ay));
        grCarInfo[index].wheelRot[i]->setTransform(&wheelpos);
        for (j = 0; j < 3; j++) {
            if (fabs(car->_wheelSpinVel(i)) < maxVel[j]) 
                break;
        }
        grCarInfo[index].wheelselector[i]->select(1<<j);
        clr = grCarInfo[index].brkColor[i]->get(0);
        clr[0] = 0.1 + car->_brakeTemp(i) * 1.5;
        clr[1] = 0.1 + car->_brakeTemp(i) * 0.3;
        clr[2] = 0.1 - car->_brakeTemp(i) * 0.3;
    }

    /* push the car at the end of the display order */
    CarsAnchorTmp->addKid(grCarInfo[index].carTransform);
    CarsAnchor->removeKid(grCarInfo[index].carTransform);
    CarsAnchor->addKid(grCarInfo[index].carTransform);
    CarsAnchorTmp->removeKid(grCarInfo[index].carTransform);

    TRACE_GL("cggrDrawCar: end");
}