test/testgesture.c
author Sam Lantinga <slouken@libsdl.org>
Mon, 23 Jun 2014 11:06:50 -0700
changeset 8917 23182cf59f1c
parent 8883 0700ef83072a
child 9235 ba9988f0daec
permissions -rw-r--r--
Don't redefine standard macros, use SDL specific macros instead to avoid compiler warnings
     1 /*
     2   Copyright (C) 1997-2014 Sam Lantinga <slouken@libsdl.org>
     3 
     4   This software is provided 'as-is', without any express or implied
     5   warranty.  In no event will the authors be held liable for any damages
     6   arising from the use of this software.
     7 
     8   Permission is granted to anyone to use this software for any purpose,
     9   including commercial applications, and to alter it and redistribute it
    10   freely.
    11 */
    12 /*  Usage:
    13  *  Spacebar to begin recording a gesture on all touches.
    14  *  s to save all touches into "./gestureSave"
    15  *  l to load all touches from "./gestureSave"
    16  */
    17 
    18 #include <stdio.h>
    19 #include <math.h>
    20 
    21 #include "SDL.h"
    22 #include "SDL_touch.h"
    23 #include "SDL_gesture.h"
    24 
    25 #define WIDTH 640
    26 #define HEIGHT 480
    27 #define BPP 4
    28 #define DEPTH 32
    29 
    30 /* MUST BE A POWER OF 2! */
    31 #define EVENT_BUF_SIZE 256
    32 
    33 
    34 #define VERBOSE 0
    35 
    36 static SDL_Window *window;
    37 static SDL_Event events[EVENT_BUF_SIZE];
    38 static int eventWrite;
    39 
    40 
    41 static int colors[7] = {0xFF,0xFF00,0xFF0000,0xFFFF00,0x00FFFF,0xFF00FF,0xFFFFFF};
    42 
    43 typedef struct {
    44   float x,y;
    45 } Point;
    46 
    47 typedef struct {
    48   float ang,r;
    49   Point p;
    50 } Knob;
    51 
    52 static Knob knob;
    53 
    54 void handler (int sig)
    55 {
    56   SDL_Log ("exiting...(%d)", sig);
    57   exit (0);
    58 }
    59 
    60 void perror_exit (char *error)
    61 {
    62   perror (error);
    63   handler (9);
    64 }
    65 
    66 void setpix(SDL_Surface *screen, float _x, float _y, unsigned int col)
    67 {
    68   Uint32 *pixmem32;
    69   Uint32 colour;
    70   Uint8 r,g,b;
    71   int x = (int)_x;
    72   int y = (int)_y;
    73   float a;
    74 
    75   if(x < 0 || x >= screen->w) return;
    76   if(y < 0 || y >= screen->h) return;
    77 
    78   pixmem32 = (Uint32*) screen->pixels  + y*screen->pitch/BPP + x;
    79 
    80   SDL_memcpy(&colour,pixmem32,screen->format->BytesPerPixel);
    81 
    82   SDL_GetRGB(colour,screen->format,&r,&g,&b);
    83   /* r = 0;g = 0; b = 0; */
    84   a = (float)((col>>24)&0xFF);
    85   if(a == 0) a = 0xFF; /* Hack, to make things easier. */
    86   a /= 0xFF;
    87   r = (Uint8)(r*(1-a) + ((col>>16)&0xFF)*(a));
    88   g = (Uint8)(g*(1-a) + ((col>> 8)&0xFF)*(a));
    89   b = (Uint8)(b*(1-a) + ((col>> 0)&0xFF)*(a));
    90   colour = SDL_MapRGB( screen->format,r, g, b);
    91 
    92 
    93   *pixmem32 = colour;
    94 }
    95 
    96 void drawLine(SDL_Surface *screen,float x0,float y0,float x1,float y1,unsigned int col) {
    97   float t;
    98   for(t=0;t<1;t+=(float)(1.f/SDL_max(SDL_fabs(x0-x1),SDL_fabs(y0-y1))))
    99     setpix(screen,x1+t*(x0-x1),y1+t*(y0-y1),col);
   100 }
   101 
   102 void drawCircle(SDL_Surface* screen,float x,float y,float r,unsigned int c)
   103 {
   104   float tx,ty;
   105   float xr;
   106   for(ty = (float)-SDL_fabs(r);ty <= (float)SDL_fabs((int)r);ty++) {
   107     xr = (float)sqrt(r*r - ty*ty);
   108     if(r > 0) { /* r > 0 ==> filled circle */
   109       for(tx=-xr+.5f;tx<=xr-.5;tx++) {
   110     setpix(screen,x+tx,y+ty,c);
   111       }
   112     }
   113     else {
   114       setpix(screen,x-xr+.5f,y+ty,c);
   115       setpix(screen,x+xr-.5f,y+ty,c);
   116     }
   117   }
   118 }
   119 
   120 void drawKnob(SDL_Surface* screen,Knob k) {
   121   drawCircle(screen,k.p.x*screen->w,k.p.y*screen->h,k.r*screen->w,0xFFFFFF);
   122   drawCircle(screen,(k.p.x+k.r/2*SDL_cosf(k.ang))*screen->w,
   123                 (k.p.y+k.r/2*SDL_sinf(k.ang))*screen->h,k.r/4*screen->w,0);
   124 }
   125 
   126 void DrawScreen(SDL_Surface* screen)
   127 {
   128   int i;
   129 #if 1
   130   SDL_FillRect(screen, NULL, 0);
   131 #else
   132   int x, y;
   133   for(y = 0;y < screen->h;y++)
   134     for(x = 0;x < screen->w;x++)
   135     setpix(screen,(float)x,(float)y,((x%255)<<16) + ((y%255)<<8) + (x+y)%255);
   136 #endif
   137 
   138   /* draw Touch History */
   139   for(i = eventWrite; i < eventWrite+EVENT_BUF_SIZE; ++i) {
   140     const SDL_Event *event = &events[i&(EVENT_BUF_SIZE-1)];
   141     float age = (float)(i - eventWrite) / EVENT_BUF_SIZE;
   142     float x, y;
   143     unsigned int c, col;
   144 
   145     if(event->type == SDL_FINGERMOTION ||
   146        event->type == SDL_FINGERDOWN ||
   147        event->type == SDL_FINGERUP) {
   148       x = event->tfinger.x;
   149       y = event->tfinger.y;
   150 
   151       /* draw the touch: */
   152       c = colors[event->tfinger.fingerId%7];
   153       col = ((unsigned int)(c*(.1+.85))) | (unsigned int)(0xFF*age)<<24;
   154 
   155       if(event->type == SDL_FINGERMOTION)
   156     drawCircle(screen,x*screen->w,y*screen->h,5,col);
   157       else if(event->type == SDL_FINGERDOWN)
   158     drawCircle(screen,x*screen->w,y*screen->h,-10,col);
   159     }
   160   }
   161 
   162   if(knob.p.x > 0)
   163     drawKnob(screen,knob);
   164 
   165   SDL_UpdateWindowSurface(window);
   166 }
   167 
   168 SDL_Surface* initScreen(int width,int height)
   169 {
   170   if (!window) {
   171     window = SDL_CreateWindow("Gesture Test",
   172                               SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
   173                               width, height, SDL_WINDOW_RESIZABLE);
   174   }
   175   if (!window) {
   176     return NULL;
   177   }
   178   return SDL_GetWindowSurface(window);
   179 }
   180 
   181 int main(int argc, char* argv[])
   182 {
   183   SDL_Surface *screen;
   184   SDL_Event event;
   185   SDL_bool quitting = SDL_FALSE;
   186   SDL_RWops *stream;
   187 
   188   /* Enable standard application logging */
   189   SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
   190 
   191   /* gesture variables */
   192   knob.r = .1f;
   193   knob.ang = 0;
   194 
   195   if (SDL_Init(SDL_INIT_VIDEO) < 0 ) return 1;
   196 
   197   if (!(screen = initScreen(WIDTH,HEIGHT)))
   198     {
   199       SDL_Quit();
   200       return 1;
   201     }
   202 
   203   while(!quitting) {
   204     while(SDL_PollEvent(&event))
   205       {
   206     /* Record _all_ events */
   207     events[eventWrite & (EVENT_BUF_SIZE-1)] = event;
   208     eventWrite++;
   209 
   210     switch (event.type)
   211       {
   212       case SDL_QUIT:
   213         quitting = SDL_TRUE;
   214         break;
   215       case SDL_KEYDOWN:
   216         switch (event.key.keysym.sym)
   217           {
   218           case SDLK_SPACE:
   219         SDL_RecordGesture(-1);
   220         break;
   221           case SDLK_s:
   222         stream = SDL_RWFromFile("gestureSave", "w");
   223         SDL_Log("Wrote %i templates", SDL_SaveAllDollarTemplates(stream));
   224         SDL_RWclose(stream);
   225         break;
   226           case SDLK_l:
   227         stream = SDL_RWFromFile("gestureSave", "r");
   228         SDL_Log("Loaded: %i", SDL_LoadDollarTemplates(-1, stream));
   229         SDL_RWclose(stream);
   230         break;
   231           case SDLK_ESCAPE:
   232         quitting = SDL_TRUE;
   233         break;
   234         }
   235         break;
   236       case SDL_WINDOWEVENT:
   237             if (event.window.event == SDL_WINDOWEVENT_RESIZED) {
   238           if (!(screen = initScreen(event.window.data1, event.window.data2)))
   239           {
   240         SDL_Quit();
   241         return 1;
   242           }
   243             }
   244         break;
   245       case SDL_FINGERMOTION:
   246 #if VERBOSE
   247         SDL_Log("Finger: %"SDL_PRIs64",x: %f, y: %f",event.tfinger.fingerId,
   248                event.tfinger.x,event.tfinger.y);
   249 #endif
   250         break;
   251       case SDL_FINGERDOWN:
   252 #if VERBOSE
   253         SDL_Log("Finger: %"SDL_PRIs64" down - x: %f, y: %f",
   254            event.tfinger.fingerId,event.tfinger.x,event.tfinger.y);
   255 #endif
   256         break;
   257       case SDL_FINGERUP:
   258 #if VERBOSE
   259         SDL_Log("Finger: %"SDL_PRIs64" up - x: %f, y: %f",
   260                event.tfinger.fingerId,event.tfinger.x,event.tfinger.y);
   261 #endif
   262         break;
   263       case SDL_MULTIGESTURE:
   264 #if VERBOSE
   265         SDL_Log("Multi Gesture: x = %f, y = %f, dAng = %f, dR = %f",
   266            event.mgesture.x,
   267            event.mgesture.y,
   268            event.mgesture.dTheta,
   269            event.mgesture.dDist);
   270         SDL_Log("MG: numDownTouch = %i",event.mgesture.numFingers);
   271 #endif
   272         knob.p.x = event.mgesture.x;
   273         knob.p.y = event.mgesture.y;
   274         knob.ang += event.mgesture.dTheta;
   275         knob.r += event.mgesture.dDist;
   276         break;
   277       case SDL_DOLLARGESTURE:
   278         SDL_Log("Gesture %"SDL_PRIs64" performed, error: %f",
   279            event.dgesture.gestureId,
   280            event.dgesture.error);
   281         break;
   282       case SDL_DOLLARRECORD:
   283         SDL_Log("Recorded gesture: %"SDL_PRIs64"",event.dgesture.gestureId);
   284         break;
   285       }
   286       }
   287     DrawScreen(screen);
   288   }
   289   SDL_Quit();
   290   return 0;
   291 }
   292