This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
gestureTest.c
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#include <stdio.h>
#include <SDL.h>
#include <math.h>
#include <SDL_touch.h>
#define PI 3.1415926535897
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#define PHI ((sqrt(5)-1)/2)
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#define WIDTH 640
#define HEIGHT 480
#define BPP 4
#define DEPTH 32
#define MAXFINGERS 3
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#define DOLLARNPOINTS 64
#define DOLLARSIZE 256
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//MUST BE A POWER OF 2!
#define EVENT_BUF_SIZE 256
SDL_Event events[EVENT_BUF_SIZE];
int eventWrite;
int mousx,mousy;
int keystat[512];
int bstatus;
int colors[7] = {0xFF,0xFF00,0xFF0000,0xFFFF00,0x00FFFF,0xFF00FF,0xFFFFFF};
int index2fingerid[MAXFINGERS];
int fingersDown;
typedef struct {
float x,y;
} Point;
typedef struct {
Point p;
float pressure;
int id;
} Finger;
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typedef struct {
Finger f;
Point cv;
float dtheta,dDist;
} TouchPoint;
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typedef struct { //dt + s
Point d,s; //direction, start
int points;
} Line;
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typedef struct {
float length;
int numPoints;
Point p[EVENT_BUF_SIZE]; //To be safe
} DollarPath;
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typedef struct {
float ang,r;
Point p;
} Knob;
Knob knob;
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Finger finger[MAXFINGERS];
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DollarPath dollarPath[MAXFINGERS];
#define MAXTEMPLATES 4
Point dollarTemplate[MAXTEMPLATES][DOLLARNPOINTS];
int numDollarTemplates = 0;
#ifdef DRAW_VECTOR_EST
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Line gestureLine[MAXFINGERS];
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#endif
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void handler (int sig)
{
printf ("\exiting...(%d)\n", sig);
exit (0);
}
void perror_exit (char *error)
{
perror (error);
handler (9);
}
void setpix(SDL_Surface *screen, int x, int y, unsigned int col)
{
Uint32 *pixmem32;
Uint32 colour;
if((unsigned)x > screen->w) return;
if((unsigned)y > screen->h) return;
pixmem32 = (Uint32*) screen->pixels + y*screen->pitch/BPP + x;
Uint8 r,g,b;
float a;
memcpy(&colour,pixmem32,screen->format->BytesPerPixel);
SDL_GetRGB(colour,screen->format,&r,&g,&b); //Always returns 0xFFFFFF?
//r = 0;g = 0; b = 0;
a = (col>>24)&0xFF;
if(a == 0) a = 0xFF; //Hack, to make things easier.
a /= 0xFF;
r = r*(1-a) + ((col>>16)&0xFF)*(a);
g = g*(1-a) + ((col>> 8)&0xFF)*(a);
b = b*(1-a) + ((col>> 0)&0xFF)*(a);
colour = SDL_MapRGB( screen->format,r, g, b);
*pixmem32 = colour;
}
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void drawLine(SDL_Surface *screen,int x0,int y0,int x1,int y1,unsigned int col) {
float t;
for(t=0;t<1;t+=1.f/SDL_max(abs(x0-x1),abs(y0-y1)))
setpix(screen,x1+t*(x0-x1),y1+t*(y0-y1),col);
}
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void drawCircle(SDL_Surface* screen,int x,int y,int r,unsigned int c)
{
float a;
int tx;
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int ty;
float xr;
for(ty = -abs(r);ty <= abs(r);ty++) {
xr = sqrt(r*r - ty*ty);
if(r > 0) { //r > 0 ==> filled circle
for(tx=-xr+.5;tx<=xr-.5;tx++) {
setpix(screen,x+tx,y+ty,c);
}
}
else {
setpix(screen,x-xr+.5,y+ty,c);
setpix(screen,x+xr-.5,y+ty,c);
}
}
}
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void drawKnob(SDL_Surface* screen,Knob k) {
printf("Knob: x = %f, y = %f, r = %f, a = %f\n",k.p.x,k.p.y,k.r,k.ang);
drawCircle(screen,k.p.x*screen->w,k.p.y*screen->h,k.r*screen->w,0xFFFFFF);
drawCircle(screen,(k.p.x+k.r/2*cos(k.ang))*screen->w,
(k.p.y+k.r/2*sin(k.ang))*screen->h,k.r/4*screen->w,0);
}
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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);
}
}
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/*
if(f1 <= f2)
printf("Min angle (x1): %f\n",x1);
else if(f1 > f2)
printf("Min angle (x2): %f\n",x2);
*/
return SDL_min(f1,f2);
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}
float dollarRecognize(SDL_Surface* screen, DollarPath path,int *bestTempl) {
Point points[DOLLARNPOINTS];
int numPoints = dollarNormalize(path,points);
int i;
int k;
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for(k = 0;k<DOLLARNPOINTS;k++) {
printf("(%f,%f)\n",points[k].x,
points[k].y);
}
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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;
}
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void DrawScreen(SDL_Surface* screen, int h)
{
int x, y, xm,ym,c;
if(SDL_MUSTLOCK(screen))
{
if(SDL_LockSurface(screen) < 0) return;
}
for(y = 0; y < screen->h; y++ )
{
for( x = 0; x < screen->w; x++ )
{
//setpixel(screen, x, y, (x*x)/256+3*y+h, (y*y)/256+x+h, h);
//xm = (x+h)%screen->w;
//ym = (y+h)%screen->w;
//c = sin(h/256*2*PI)*x*y/screen->w/screen->h;
//setpix(screen,x,y,255*sin(xm/screen->w*2*PI),sin(h/255*2*PI)*255*y/screen->h,c);
setpix(screen,x,y,((x%255)<<16) + ((y%255)<<8) + (x+y)%255);
//setpix(screen,x,y,0); //Inefficient, but that's okay...
}
}
drawCircle(screen,mousx,mousy,-30,0xFFFFFF);
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drawLine(screen,0,0,screen->w,screen->h,0xFFFFFF);
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int i;
//draw Touch History
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TouchPoint gestureLast[MAXFINGERS];
//printf("------------------Start History------------------\n");
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for(i = 0;i < MAXFINGERS;i++) {
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gestureLast[i].f.id = -1;
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int numDownFingers = 0;
Point centroid;
float gdtheta,gdDist;
for(i = SDL_max(0,eventWrite - EVENT_BUF_SIZE);i < eventWrite;i++) {
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SDL_Event event = events[i&(EVENT_BUF_SIZE-1)];
int age = eventWrite - i - 1;
if(event.type == SDL_FINGERMOTION ||
event.type == SDL_FINGERDOWN ||
event.type == SDL_FINGERUP) {
SDL_Touch* inTouch = SDL_GetTouch(event.tfinger.touchId);
//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;
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for(j = 0;j<MAXFINGERS;j++) {
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if(gestureLast[j].f.id == event.tfinger.fingerId) {
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if(event.type == SDL_FINGERUP) {
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numDownFingers--;
if(numDownFingers <= 1) {
gdtheta = 0;
gdDist = 0;
}
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if(!keystat[32]){ //spacebar
int bestTempl;
float error = dollarRecognize(screen,dollarPath[j],&bestTempl);
if(bestTempl >= 0){
drawDollarPath(screen,dollarTemplate[bestTempl]
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,DOLLARNPOINTS,-15,0x0066FF);
printf("Dollar error: %f\n",error);
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}
}
else if(numDollarTemplates < MAXTEMPLATES) {
dollarNormalize(dollarPath[j],
dollarTemplate[numDollarTemplates]);
/*
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int k;
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for(k = 0;k<DOLLARNPOINTS;k++) {
printf("(%f,%f)\n",dollarTemplate[numDollarTemplates][i].x,
dollarTemplate[numDollarTemplates][i].y);
}*/
numDollarTemplates++;
}
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gestureLast[j].f.id = -1;
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break;
}
else {
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dollarPath[j].p[dollarPath[j].numPoints].x = x;
dollarPath[j].p[dollarPath[j].numPoints].y = y;
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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);
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dollarPath[j].length += sqrt(dx*dx + dy*dy);
dollarPath[j].numPoints++;
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centroid.x = centroid.x + dx/numDownFingers;
centroid.y = centroid.y + dy/numDownFingers;
if(numDownFingers > 1) {
Point lv; //Vector from centroid to last x,y position
Point v; //Vector from centroid to current x,y position
lv.x = gestureLast[j].cv.x;
lv.y = gestureLast[j].cv.y;
float lDist = sqrt(lv.x*lv.x + lv.y*lv.y);
v.x = x - centroid.x;
v.y = y - centroid.y;
gestureLast[j].cv = v;
float Dist = sqrt(v.x*v.x+v.y*v.y);
// cos(dTheta) = (v . lv)/(|v| * |lv|)
lv.x/=lDist;
lv.y/=lDist;
v.x/=Dist;
v.y/=Dist;
float dtheta = atan2(lv.x*v.y - lv.y*v.x,lv.x*v.x + lv.y*v.y);
float dDist = (lDist - Dist);
gestureLast[j].dDist = dDist;
gestureLast[j].dtheta = dtheta;
//gdtheta = gdtheta*.9 + dtheta*.1;
//gdDist = gdDist*.9 + dDist*.1
gdtheta += dtheta;
gdDist += dDist;
//printf("thetaSum = %f, distSum = %f\n",gdtheta,gdDist);
//printf("id: %i dTheta = %f, dDist = %f\n",j,dtheta,dDist);
}
else {
gestureLast[j].dDist = 0;
gestureLast[j].dtheta = 0;
gestureLast[j].cv.x = 0;
gestureLast[j].cv.y = 0;
}
gestureLast[j].f.p.x = x;
gestureLast[j].f.p.y = y;
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break;
//pressure?
}
}
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else if(gestureLast[j].f.id == -1 && empty == -1) {
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empty = j;
}
}
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if(j >= MAXFINGERS && empty >= 0) {
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// printf("Finger Down!!!\n");
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numDownFingers++;
centroid.x = (centroid.x*(numDownFingers - 1) + x)/numDownFingers;
centroid.y = (centroid.y*(numDownFingers - 1) + y)/numDownFingers;
j = empty;
gestureLast[j].f.id = event.tfinger.fingerId;
gestureLast[j].f.p.x = x;
gestureLast[j].f.p.y = y;
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dollarPath[j].length = 0;
dollarPath[j].p[0].x = x;
dollarPath[j].p[0].y = y;
dollarPath[j].numPoints = 1;
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//draw the touch:
if(gestureLast[j].f.id < 0) continue; //Finger up. Or some error...
unsigned int c = colors[gestureLast[j].f.id%7];
unsigned int col =
((unsigned int)(c*(.1+.85))) |
((unsigned int)((0xFF*(1-((float)age)/EVENT_BUF_SIZE))) & 0xFF)<<24;
x = gestureLast[j].f.p.x;
y = gestureLast[j].f.p.y;
if(event.type == SDL_FINGERMOTION)
drawCircle(screen,x*screen->w,y*screen->h,5,col);
else if(event.type == SDL_FINGERDOWN)
drawCircle(screen,x*screen->w,y*screen->h,-10,col);
//if there is a centroid, draw it
if(numDownFingers > 1) {
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unsigned int col =
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((unsigned int)(0xFFFFFF)) |
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((unsigned int)((0xFF*(1-((float)age)/EVENT_BUF_SIZE))) & 0xFF)<<24;
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drawCircle(screen,centroid.x*screen->w,centroid.y*screen->h,5,col);
}
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}
}
for(i=0;i<MAXFINGERS;i++)
if(finger[i].p.x >= 0 && finger[i].p.y >= 0)
if(finger[i].pressure > 0)
drawCircle(screen,finger[i].p.x*screen->w,finger[i].p.y*screen->h
,20,0xFF*finger[i].pressure);
else
drawCircle(screen,finger[i].p.x*screen->w,finger[i].p.y*screen->h
,20,0xFF);
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keystat[32] = 0;
if(knob.p.x > 0)
drawKnob(screen,knob);
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if(SDL_MUSTLOCK(screen)) SDL_UnlockSurface(screen);
SDL_Flip(screen);
}
SDL_Surface* initScreen(int width,int height)
{
return SDL_SetVideoMode(width, height, DEPTH,
SDL_HWSURFACE | SDL_RESIZABLE);
}
int main(int argc, char* argv[])
{
SDL_Surface *screen;
SDL_Event event;
int keypress = 0;
int h=0,s=1,i,j;
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//gesture variables
int numDownFingers = 0;
float gdtheta = 0,gdDist = 0;
Point centroid;
knob.r = .1;
knob.ang = 0;
TouchPoint gestureLast[MAXFINGERS];
for(i = 0;i < MAXFINGERS;i++)
gestureLast[i].f.id = -1;
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memset(keystat,0,512*sizeof(keystat[0]));
if (SDL_Init(SDL_INIT_VIDEO) < 0 ) return 1;
if (!(screen = initScreen(WIDTH,HEIGHT)))
{
SDL_Quit();
return 1;
}
while(!keystat[27]) {
//Poll SDL
while(SDL_PollEvent(&event))
{
//Record _all_ events
events[eventWrite & (EVENT_BUF_SIZE-1)] = event;
eventWrite++;
switch (event.type)
{
case SDL_QUIT:
keystat[27] = 1;
break;
case SDL_KEYDOWN:
//printf("%i\n",event.key.keysym.sym);
keystat[event.key.keysym.sym] = 1;
//keypress = 1;
break;
case SDL_KEYUP:
//printf("%i\n",event.key.keysym.sym);
keystat[event.key.keysym.sym] = 0;
//keypress = 1;
break;
case SDL_VIDEORESIZE:
if (!(screen = initScreen(event.resize.w,
event.resize.h)))
{
SDL_Quit();
return 1;
}
break;
case SDL_MOUSEMOTION:
mousx = event.motion.x;
mousy = event.motion.y;
break;
case SDL_MOUSEBUTTONDOWN:
bstatus |= (1<<(event.button.button-1));
break;
case SDL_MOUSEBUTTONUP:
bstatus &= ~(1<<(event.button.button-1));
break;
case SDL_FINGERMOTION:
;
//printf("Finger: %i,x: %i, y: %i\n",event.tfinger.fingerId,
// event.tfinger.x,event.tfinger.y);
SDL_Touch* inTouch = SDL_GetTouch(event.tfinger.touchId);
SDL_Finger* inFinger = SDL_GetFinger(inTouch,event.tfinger.fingerId);
for(i = 0;i<MAXFINGERS;i++)
if(index2fingerid[i] == event.tfinger.fingerId)
break;
if(i == MAXFINGERS) break;
if(inTouch > 0) {
finger[i].p.x = ((float)event.tfinger.x)/
inTouch->xres;
finger[i].p.y = ((float)event.tfinger.y)/
inTouch->yres;
finger[i].pressure =
((float)event.tfinger.pressure)/inTouch->pressureres;
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printf("Finger: %i, Pressure: %f Pressureres: %i\n",
event.tfinger.fingerId,
finger[i].pressure,
inTouch->pressureres);
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//printf("Finger: %i, pressure: %f\n",event.tfinger.fingerId,
// finger[event.tfinger.fingerId].pressure);
}
break;
case SDL_FINGERDOWN:
printf("Finger: %i down - x: %i, y: %i\n",event.tfinger.fingerId,
event.tfinger.x,event.tfinger.y);
for(i = 0;i<MAXFINGERS;i++)
if(index2fingerid[i] == -1) {
index2fingerid[i] = event.tfinger.fingerId;
break;
}
finger[i].p.x = event.tfinger.x;
finger[i].p.y = event.tfinger.y;
break;
case SDL_FINGERUP:
printf("Figner: %i up - x: %i, y: %i\n",event.tfinger.fingerId,
event.tfinger.x,event.tfinger.y);
for(i = 0;i<MAXFINGERS;i++)
if(index2fingerid[i] == event.tfinger.fingerId) {
index2fingerid[i] = -1;
break;
}
finger[i].p.x = -1;
finger[i].p.y = -1;
break;
}
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if(event.type == SDL_FINGERMOTION ||
event.type == SDL_FINGERDOWN ||
event.type == SDL_FINGERUP) {
SDL_Touch* inTouch = SDL_GetTouch(event.tfinger.touchId);
//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].f.id == event.tfinger.fingerId) {
if(event.type == SDL_FINGERUP) {
numDownFingers--;
if(numDownFingers <= 1) {
gdtheta = 0;
gdDist = 0;
}
gestureLast[j].f.id = -1;
break;
}
else {
float dx = x - gestureLast[j].f.p.x;
float dy = y - gestureLast[j].f.p.y;
centroid.x = centroid.x + dx/numDownFingers;
centroid.y = centroid.y + dy/numDownFingers;
if(numDownFingers > 1) {
Point lv; //Vector from centroid to last x,y position
Point v; //Vector from centroid to current x,y position
lv = gestureLast[j].cv;
float lDist = sqrt(lv.x*lv.x + lv.y*lv.y);
printf("lDist = %f\n",lDist);
v.x = x - centroid.x;
v.y = y - centroid.y;
gestureLast[j].cv = v;
float Dist = sqrt(v.x*v.x+v.y*v.y);
// cos(dTheta) = (v . lv)/(|v| * |lv|)
lv.x/=lDist;
lv.y/=lDist;
v.x/=Dist;
v.y/=Dist;
float dtheta = atan2(lv.x*v.y - lv.y*v.x,lv.x*v.x + lv.y*v.y);
float dDist = (Dist - lDist);
if(lDist == 0) {dDist = 0;dtheta = 0;}
gestureLast[j].dDist = dDist;
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);
}
else {
gestureLast[j].dDist = 0;
gestureLast[j].dtheta = 0;
gestureLast[j].cv.x = 0;
gestureLast[j].cv.y = 0;
}
gestureLast[j].f.p.x = x;
gestureLast[j].f.p.y = y;
break;
//pressure?
}
}
else if(gestureLast[j].f.id == -1 && empty == -1) {
empty = j;
}
}
if(j >= MAXFINGERS && empty >= 0) {
printf("Finger Down!!!\n");
numDownFingers++;
centroid.x = (centroid.x*(numDownFingers - 1) + x)/numDownFingers;
centroid.y = (centroid.y*(numDownFingers - 1) + y)/numDownFingers;
j = empty;
gestureLast[j].f.id = event.tfinger.fingerId;
gestureLast[j].f.p.x = x;
gestureLast[j].f.p.y = y;
gestureLast[j].cv.x = 0;
gestureLast[j].cv.y = 0;
}
//draw the touch:
}
//And draw
if(numDownFingers > 1)
knob.p = centroid;
else
knob.p.x = -1;
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}
DrawScreen(screen,h);
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//printf("c: (%f,%f)\n",centroid.x,centroid.y);
//printf("numDownFingers: %i\n",numDownFingers);
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//for(i=0;i<512;i++)
// if(keystat[i]) printf("%i\n",i);
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}
SDL_Quit();
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return 0;
}