static float dollarRecognize(const SDL_DollarPath *path,int *bestTempl,SDL_GestureTouch* touch)
{
SDL_FloatPoint points[DOLLARNPOINTS];
int i;
float bestDiff = 10000;
dollarNormalize(path,points);
//PrintPath(points);
*bestTempl = -1;
for (i = 0; i < touch->numDollarTemplates; i++) {
float diff = bestDollarDifference(points,touch->dollarTemplate[i].path);
if (diff < bestDiff) {bestDiff = diff; *bestTempl = i;}
}
return bestDiff;
}
void SDL_GestureProcessEvent(SDL_Event* event)
{
float x,y;
SDL_FloatPoint path[DOLLARNPOINTS];
int index;
int i;
float pathDx, pathDy;
SDL_FloatPoint lastP;
SDL_FloatPoint lastCentroid;
float lDist;
float Dist;
float dtheta;
float dDist;
if (event->type == SDL_FINGERMOTION ||
event->type == SDL_FINGERDOWN ||
event->type == SDL_FINGERUP) {
SDL_GestureTouch* inTouch = SDL_GetGestureTouch(event->tfinger.touchId);
/* Shouldn't be possible */
if (inTouch == NULL) return;
x = event->tfinger.x;
y = event->tfinger.y;
/* Finger Up */
if (event->type == SDL_FINGERUP) {
inTouch->numDownFingers--;
#ifdef ENABLE_DOLLAR
if (inTouch->recording) {
inTouch->recording = SDL_FALSE;
dollarNormalize(&inTouch->dollarPath,path);
/* PrintPath(path); */
if (recordAll) {
index = SDL_AddDollarGesture(NULL,path);
for (i = 0; i < SDL_numGestureTouches; i++)
SDL_gestureTouch[i].recording = SDL_FALSE;
}
else {
index = SDL_AddDollarGesture(inTouch,path);
}
if (index >= 0) {
SDL_SendDollarRecord(inTouch,inTouch->dollarTemplate[index].hash);
}
else {
SDL_SendDollarRecord(inTouch,-1);
}
}
else {
int bestTempl;
float error;
error = dollarRecognize(&inTouch->dollarPath,
&bestTempl,inTouch);
if (bestTempl >= 0){
/* Send Event */
unsigned long gestureId = inTouch->dollarTemplate[bestTempl].hash;
SDL_SendGestureDollar(inTouch,gestureId,error);
/* printf ("%s\n",);("Dollar error: %f\n",error); */
}
}
#endif
/* inTouch->gestureLast[j] = inTouch->gestureLast[inTouch->numDownFingers]; */
if (inTouch->numDownFingers > 0) {
inTouch->centroid.x = (inTouch->centroid.x*(inTouch->numDownFingers+1)-
x)/inTouch->numDownFingers;
inTouch->centroid.y = (inTouch->centroid.y*(inTouch->numDownFingers+1)-
y)/inTouch->numDownFingers;
}
}
else if (event->type == SDL_FINGERMOTION) {
float dx = event->tfinger.dx;
float dy = event->tfinger.dy;
#ifdef ENABLE_DOLLAR
SDL_DollarPath* path = &inTouch->dollarPath;
if (path->numPoints < MAXPATHSIZE) {
path->p[path->numPoints].x = inTouch->centroid.x;
path->p[path->numPoints].y = inTouch->centroid.y;
pathDx =
(path->p[path->numPoints].x-path->p[path->numPoints-1].x);
pathDy =
(path->p[path->numPoints].y-path->p[path->numPoints-1].y);
path->length += (float)SDL_sqrt(pathDx*pathDx + pathDy*pathDy);
path->numPoints++;
}
#endif
lastP.x = x - dx;
lastP.y = y - dy;
lastCentroid = inTouch->centroid;
inTouch->centroid.x += dx/inTouch->numDownFingers;
inTouch->centroid.y += dy/inTouch->numDownFingers;
/* printf("Centrid : (%f,%f)\n",inTouch->centroid.x,inTouch->centroid.y); */
if (inTouch->numDownFingers > 1) {
SDL_FloatPoint lv; /* Vector from centroid to last x,y position */
SDL_FloatPoint v; /* Vector from centroid to current x,y position */
/* lv = inTouch->gestureLast[j].cv; */
lv.x = lastP.x - lastCentroid.x;
lv.y = lastP.y - lastCentroid.y;
lDist = (float)SDL_sqrt(lv.x*lv.x + lv.y*lv.y);
/* printf("lDist = %f\n",lDist); */
v.x = x - inTouch->centroid.x;
v.y = y - inTouch->centroid.y;
/* inTouch->gestureLast[j].cv = v; */
Dist = (float)SDL_sqrt(v.x*v.x+v.y*v.y);
/* SDL_cos(dTheta) = (v . lv)/(|v| * |lv|) */
/* Normalize Vectors to simplify angle calculation */
lv.x/=lDist;
lv.y/=lDist;
v.x/=Dist;
v.y/=Dist;
dtheta = (float)SDL_atan2(lv.x*v.y - lv.y*v.x,lv.x*v.x + lv.y*v.y);
dDist = (Dist - lDist);
if (lDist == 0) {dDist = 0;dtheta = 0;} /* To avoid impossible values */
/* inTouch->gestureLast[j].dDist = dDist;
inTouch->gestureLast[j].dtheta = dtheta;
printf("dDist = %f, dTheta = %f\n",dDist,dtheta);
gdtheta = gdtheta*.9 + dtheta*.1;
gdDist = gdDist*.9 + dDist*.1
knob.r += dDist/numDownFingers;
knob.ang += dtheta;
printf("thetaSum = %f, distSum = %f\n",gdtheta,gdDist);
printf("id: %i dTheta = %f, dDist = %f\n",j,dtheta,dDist); */
SDL_SendGestureMulti(inTouch,dtheta,dDist);
}
else {
/* inTouch->gestureLast[j].dDist = 0;
inTouch->gestureLast[j].dtheta = 0;
inTouch->gestureLast[j].cv.x = 0;
inTouch->gestureLast[j].cv.y = 0; */
}
/* inTouch->gestureLast[j].f.p.x = x;
inTouch->gestureLast[j].f.p.y = y;
break;
pressure? */
}
if (event->type == SDL_FINGERDOWN) {
inTouch->numDownFingers++;
inTouch->centroid.x = (inTouch->centroid.x*(inTouch->numDownFingers - 1)+
x)/inTouch->numDownFingers;
inTouch->centroid.y = (inTouch->centroid.y*(inTouch->numDownFingers - 1)+
y)/inTouch->numDownFingers;
/* printf("Finger Down: (%f,%f). Centroid: (%f,%f\n",x,y,
inTouch->centroid.x,inTouch->centroid.y); */
#ifdef ENABLE_DOLLAR
inTouch->dollarPath.length = 0;
inTouch->dollarPath.p[0].x = x;
inTouch->dollarPath.p[0].y = y;
inTouch->dollarPath.numPoints = 1;
#endif
}
}
}