sdl-ios-xcode: touchTest/gestureTest.c comparison

comparison touchTest/gestureTest.c @ 4654:7dbcd71216df

Added $1 gesture recognition. Functional.

author	Jim Grandpre <jim.tla@gmail.com>
date	Thu, 17 Jun 2010 03:41:27 -0400
parents	744b75ad18b8
children	4c94f2023d62

comparison

equal deleted inserted replaced

-:744b75ad18b8
+:7dbcd71216df
 #include <SDL.h>
 #include <math.h>
 #include <SDL_touch.h>
 #define PI 3.1415926535897
+#define PHI ((sqrt(5)-1)/2)
 #define WIDTH 640
 #define HEIGHT 480
 #define BPP 4
 #define DEPTH 32
 #define MAXFINGERS 3
+#define DOLLARNPOINTS 64
+#define DOLLARSIZE 256
 //MUST BE A POWER OF 2!
 #define EVENT_BUF_SIZE 256
 SDL_Event events[EVENT_BUF_SIZE];
 Point d,s; //direction, start
 int points;
 } Line;
+typedef struct {
+float length;
+int numPoints;
+Point p[EVENT_BUF_SIZE]; //To be safe
+} DollarPath;
 Finger finger[MAXFINGERS];
 Finger gestureLast[MAXFINGERS];
+DollarPath dollarPath[MAXFINGERS];
+#define MAXTEMPLATES 4
+Point dollarTemplate[MAXTEMPLATES][DOLLARNPOINTS];
+int numDollarTemplates = 0;
+#ifdef DRAW_VECTOR_EST
 Line gestureLine[MAXFINGERS];
+#endif
 void handler (int sig)
 {
 printf ("\exiting...(%d)\n", sig);
 exit (0);
 if(r > 0) { //r > 0 ==> filled circle
 for(tx=x-r*cos(a);tx<x+r*cos(a);tx++) {
 	setpix(screen,tx,(int)(y+r*sin(a)),c);
 	setpix(screen,tx,(int)(y-r*sin(a)),c);
 }
-}
+}    else {
-else {
 //Draw Outline
 setpix(screen,(int)(x+r*cos(a)),(int)(y+r*sin(a)),c);
 setpix(screen,(int)(x-r*cos(a)),(int)(y+r*sin(a)),c);
 setpix(screen,(int)(x+r*cos(a)),(int)(y-r*sin(a)),c);
 setpix(screen,(int)(x-r*cos(a)),(int)(y-r*sin(a)),c);
 else {
 setpix(screen,x-xr+.5,y+ty,c);
 setpix(screen,x+xr-.5,y+ty,c);
 }
 }
+}
+void drawDollarPath(SDL_Surface* screen,Point* points,int numPoints,
+		    int rad,unsigned int col){
+int i;
+for(i=0;i<numPoints;i++) {
+drawCircle(screen,points[i].x+screen->w/2,
+	       points[i].y+screen->h/2,
+	       rad,col);
+}
+}
+float dollarDifference(Point* points,Point* templ,float ang) {
+//  Point p[DOLLARNPOINTS];
+float dist = 0;
+Point p;
+int i;
+for(i = 0; i < DOLLARNPOINTS; i++) {
+p.x = points[i].x * cos(ang) - points[i].y * sin(ang);
+p.y = points[i].x * sin(ang) + points[i].y * cos(ang);
+dist += sqrt((p.x-templ[i].x)*(p.x-templ[i].x)+
+		 (p.y-templ[i].y)*(p.y-templ[i].y));
+}
+return dist/DOLLARNPOINTS;
+}
+float bestDollarDifference(Point* points,Point* templ) {
+//------------BEGIN DOLLAR BLACKBOX----------------//
+//-TRANSLATED DIRECTLY FROM PSUDEO-CODE AVAILABLE AT-//
+//-"http://depts.washington.edu/aimgroup/proj/dollar/"-//
+float ta = -PI/4;
+float tb = PI/4;
+float dt = PI/90;
+float x1 = PHI*ta + (1-PHI)*tb;
+float f1 = dollarDifference(points,templ,x1);
+float x2 = (1-PHI)*ta + PHI*tb;
+float f2 = dollarDifference(points,templ,x2);
+while(abs(ta-tb) > dt) {
+if(f1 < f2) {
+tb = x2;
+x2 = x1;
+f2 = f1;
+x1 = PHI*ta + (1-PHI)*tb;
+f1 = dollarDifference(points,templ,x1);
+}
+else {
+ta = x1;
+x1 = x2;
+f1 = f2;
+x2 = (1-PHI)*ta + PHI*tb;
+f2 = dollarDifference(points,templ,x2);
+}
+}
+return SDL_min(f1,f2);
+}
+float dollarRecognize(SDL_Surface* screen, DollarPath path,int *bestTempl) {
+Point points[DOLLARNPOINTS];
+int numPoints = dollarNormalize(path,points);
+int i;
+int k;
+for(k = 0;k<DOLLARNPOINTS;k++) {
+printf("(%f,%f)\n",points[k].x,
+	   points[k].y);
+}
+drawDollarPath(screen,points,numPoints,-15,0xFF6600);
+int bestDiff = 10000;
+*bestTempl = -1;
+for(i = 0;i < numDollarTemplates;i++) {
+int diff = bestDollarDifference(points,dollarTemplate[i]);
+if(diff < bestDiff) {bestDiff = diff; *bestTempl = i;}
+}
+return bestDiff;
+}
+//DollarPath contains raw points, plus (possibly) the calculated length
+int dollarNormalize(DollarPath path,Point *points) {
+int i;
+//Calculate length if it hasn't already been done
+if(path.length <= 0) {
+for(i=1;i<path.numPoints;i++) {
+float dx = path.p[i  ].x -
+	         path.p[i-1].x;
+float dy = path.p[i  ].y -
+	         path.p[i-1].y;
+path.length += sqrt(dx*dx+dy*dy);
+}
+}
+//Resample
+float interval = path.length/(DOLLARNPOINTS - 1);
+float dist = 0;
+int numPoints = 0;
+Point centroid; centroid.x = 0;centroid.y = 0;
+//printf("(%f,%f)\n",path.p[path.numPoints-1].x,path.p[path.numPoints-1].y);
+for(i = 1;i < path.numPoints;i++) {
+float d = sqrt((path.p[i-1].x-path.p[i].x)*(path.p[i-1].x-path.p[i].x)+
+		   (path.p[i-1].y-path.p[i].y)*(path.p[i-1].y-path.p[i].y));
+//printf("d = %f dist = %f/%f\n",d,dist,interval);
+while(dist + d > interval) {
+points[numPoints].x = path.p[i-1].x +
+	((interval-dist)/d)*(path.p[i].x-path.p[i-1].x);
+points[numPoints].y = path.p[i-1].y +
+	((interval-dist)/d)*(path.p[i].y-path.p[i-1].y);
+centroid.x += points[numPoints].x;
+centroid.y += points[numPoints].y;
+numPoints++;
+dist -= interval;
+}
+dist += d;
+}
+if(numPoints < 1) return 0;
+centroid.x /= numPoints;
+centroid.y /= numPoints;
+//printf("Centroid (%f,%f)",centroid.x,centroid.y);
+//Rotate Points so point 0 is left of centroid and solve for the bounding box
+float xmin,xmax,ymin,ymax;
+xmin = centroid.x;
+xmax = centroid.x;
+ymin = centroid.y;
+ymax = centroid.y;
+float ang = atan2(centroid.y - points[0].y,
+		    centroid.x - points[0].x);
+for(i = 0;i<numPoints;i++) {
+float px = points[i].x;
+float py = points[i].y;
+points[i].x = (px - centroid.x)*cos(ang) -
+(py - centroid.y)*sin(ang) + centroid.x;
+points[i].y = (px - centroid.x)*sin(ang) +
+(py - centroid.y)*cos(ang) + centroid.y;
+if(points[i].x < xmin) xmin = points[i].x;
+if(points[i].x > xmax) xmax = points[i].x;
+if(points[i].y < ymin) ymin = points[i].y;
+if(points[i].y > ymax) ymax = points[i].y;
+}
+//Scale points to DOLLARSIZE, and translate to the origin
+float w = xmax-xmin;
+float h = ymax-ymin;
+for(i=0;i<numPoints;i++) {
+points[i].x = (points[i].x - centroid.x)*DOLLARSIZE/w;
+points[i].y = (points[i].y - centroid.y)*DOLLARSIZE/h;
+}
+return numPoints;
 }
 void DrawScreen(SDL_Surface* screen, int h)
 {
 int x, y, xm,ym,c;
 drawLine(screen,0,0,screen->w,screen->h,0xFFFFFF);
 int i;
 //draw Touch History
 for(i = 0;i < MAXFINGERS;i++) {
 gestureLast[i].id = -1;
+#ifdef DRAW_VECTOR_EST
 gestureLine[i].points = 0;
+#endif
 }
 for(i = SDL_max(0,eventWrite - EVENT_BUF_SIZE);i != eventWrite;i++) {
 SDL_Event event = events[i&(EVENT_BUF_SIZE-1)];
 int age = eventWrite - i - 1;
 if(event.type == SDL_FINGERMOTION ||
 //SDL_Finger* inFinger = SDL_GetFinger(inTouch,event.tfinger.fingerId);
 float x = ((float)event.tfinger.x)/inTouch->xres;
 float y = ((float)event.tfinger.y)/inTouch->yres;
 int j,empty = -1;
 for(j = 0;j<MAXFINGERS;j++) {
 	if(gestureLast[j].id == event.tfinger.fingerId) {
 	  if(event.type == SDL_FINGERUP) {
+#ifdef DRAW_VECTOR_EST
 	    if(gestureLine[j].points > 0)
-	    drawLine(screen,
+	      drawLine(screen,
 		     gestureLine[j].s.x*screen->w,
 		     gestureLine[j].s.y*screen->h,
 		     (gestureLine[j].s.x +50*gestureLine[j].d.x)*screen->w,
 		     (gestureLine[j].s.y +50*gestureLine[j].d.y)*screen->h,
 		     0xFF00);
 	    gestureLine[j].points = 0;
+#endif
+	    //ignore last point - probably invalid
+	    dollarPath[j].numPoints--;
+	    float dx = dollarPath[j].p[dollarPath[j].numPoints].x -
+	      dollarPath[j].p[dollarPath[j].numPoints - 1].x;
+	    float dy = dollarPath[j].p[dollarPath[j].numPoints].y -
+	      dollarPath[j].p[dollarPath[j].numPoints - 1].y;
+	    dollarPath[j].length -= sqrt(dx*dx+dy*dy);
+	    if(!keystat[32]){ //spacebar
+	      int bestTempl;
+	      float error = dollarRecognize(screen,dollarPath[j],&bestTempl);
+	      printf("%i\n",bestTempl);
+	      if(bestTempl >= 0){
+		drawDollarPath(screen,dollarTemplate[bestTempl]
+			       ,DOLLARNPOINTS,-15,0x0066FF);\
+		printf("ERROR: %f\n",error);
+	      }
+	    }
+	    else if(numDollarTemplates < MAXTEMPLATES) {
+	      dollarNormalize(dollarPath[j],
+			      dollarTemplate[numDollarTemplates]);
+	      int k;
+	      /*
+	      for(k = 0;k<DOLLARNPOINTS;k++) {
+		printf("(%f,%f)\n",dollarTemplate[numDollarTemplates][i].x,
+		       dollarTemplate[numDollarTemplates][i].y);
+		       }*/
+	      numDollarTemplates++;
+	    }
 	    gestureLast[j].id = -1;
 	    break;
 	  }
 	  else {
+#ifdef DRAW_VECTOR_EST
 	    if(gestureLine[j].points == 1) {
 	      gestureLine[j].d.x = x - gestureLine[j].s.x;
 	      gestureLine[j].d.y = y - gestureLine[j].s.y;
 	    }
 	    gestureLine[j].s.x /= gestureLine[j].points;
 	    gestureLine[j].s.y /= gestureLine[j].points;
 	    gestureLine[j].d.x /= gestureLine[j].points;
 	    gestureLine[j].d.y /= gestureLine[j].points;
+#endif
+	    dollarPath[j].p[dollarPath[j].numPoints].x = x;
+	    dollarPath[j].p[dollarPath[j].numPoints].y = y;
+	    float dx = (dollarPath[j].p[dollarPath[j].numPoints-1].x-
+		      dollarPath[j].p[dollarPath[j].numPoints  ].x);
+	    float dy = (dollarPath[j].p[dollarPath[j].numPoints-1].y-
+		      dollarPath[j].p[dollarPath[j].numPoints  ].y);
+	    dollarPath[j].length += sqrt(dx*dx + dy*dy);
+	    dollarPath[j].numPoints++;
 	    gestureLast[j].p.x = x;
 	    gestureLast[j].p.y = y;
 	    break;
 	}
 	else if(gestureLast[j].id == -1 && empty == -1) {
 	  empty = j;
 	}
 }
 if(j >= MAXFINGERS && empty >= 0) {
-	printf("Finger Down!!!\n");
+	//	printf("Finger Down!!!\n");
 	j = empty; //important that j is the index of the added finger
 	gestureLast[j].id = event.tfinger.fingerId;
 	gestureLast[j].p.x  = x;
 	gestureLast[j].p.y  = y;
+#ifdef DRAW_VECTOR_EST
 	gestureLine[j].s.x = x;
 	gestureLine[j].s.y = y;
 	gestureLine[j].points = 1;
+#endif
+	dollarPath[j].length = 0;
+	dollarPath[j].p[0].x = x;
+	dollarPath[j].p[0].y = y;
+	dollarPath[j].numPoints = 1;
 }
 //draw the touch && each centroid:
 if(gestureLast[j].id < 0) continue; //Finger up. Or some error...
 else
 	drawCircle(screen,finger[i].p.x*screen->w,finger[i].p.y*screen->h
 		   ,20,0xFF);
+keystat[32] = 0;
 if(SDL_MUSTLOCK(screen)) SDL_UnlockSurface(screen);
 SDL_Flip(screen);
 }
 	    break;
 	  }
 }
 //And draw
 DrawScreen(screen,h);
-/*
-for(i=0;i<512;i++)
+//for(i=0;i<512;i++)
-if(keystat[i]) printf("%i\n",i);
+// if(keystat[i]) printf("%i\n",i);
-printf("Buttons:%i\n",bstatus);
-*/
 }
 SDL_Quit();
 return 0;
 }

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comparison touchTest/gestureTest.c @ 4654:7dbcd71216df