宅男遇上 Wii remote

前幾天看到同事分享 Johnny Lee的影片。心中有蠻大的震憾。一直認為 Wii Remote 已經很神奇了…沒想到還有那麼多的玩法…果然厲害。就開始想在自己的機器上玩玩 Wii Remote.

沒想到一切都是如此的美好： Ubuntu 已經有了 CWiid 的 package.
直接安裝後，把 bluetooth 打開，就可以玩了

身為一名陽光宅男…當然好好的研究一下這個好玩的東西…
也就寫了一支小小的程式…可以依 Wii remote 的水平改變小 Icon 的位置。

Filename: wii_toy.c

#include <wiimote.h>
#include <wiimote_api.h>
#include <Ecore_Evas.h>
#include <Ecore.h>
#include <stdlib.h>
#include <stdio.h>
#include <math.h>

#define WIDTH 800
#define HEIGHT 600

Ecore_Evas  *   ee;
Evas        *   evas;

struct remoter {
     Evas_Object *   o;
     wiimote_t *wii;
     double x,y,size;
};

inline void set_wiiremote(wiimote_t *wii) {
     wii->led.one  = 1;
     wii->mode.ir = 1;
     wii->mode.acc =1;
}

inline void change_position(struct remoter *handle) {
     if ( abs(handle->wii->tilt.x) <= 90 &&
                     abs (handle->wii->tilt.y) <= 90) {

             handle->x += (double)handle->wii->tilt.x/10.0f;
             handle->y += (double)handle->wii->tilt.y/10.0f;
     }
     handle->x = handle->x <= 0 ? 0 : handle->x >= WIDTH - handle->size?  WIDTH-handle->size :  handle->x;
     handle->y = handle->y <= 0 ? 0 : handle->y >= HEIGHT - handle->size? HEIGHT-handle->size : handle->y;


//      fprintf(stderr, "remote: x=%3.3f y=%3.3f\n",handle->x,handle->y);
     evas_object_move(handle->o, handle->x,handle->y);
}

inline void show_status(wiimote_t *wii) {
     fprintf(stderr, "AXIS x=%03d y=%03d z=%03d\n",
             wii->axis.x,
             wii->axis.y,
             wii->axis.z);
     fprintf(stderr, "TILT x=%.3f y=%.3f z=%.3f\n",
             wii->tilt.x,
             wii->tilt.y,
             wii->tilt.z);
     fprintf(stderr, "FORCE x=%.3f y=%.3f z=%.3f\n",
             wii->force.x,
             wii->force.y,
             wii->force.z);
     fprintf(stderr,"\n");
}

int scan_wii_event(void *data) {
     struct remoter *handle=(struct remoter *)data;
     if (wiimote_is_open(handle->wii))  {
             if (wiimote_update(handle->wii) < 0) {
                     printf("Update Failed!! Exit!!\n");
                     wiimote_disconnect(handle->wii);
                     exit(1);
             }
             if (handle->wii->keys.home) {
                     printf("Home pressed!! Exit!!\n");
                     wiimote_disconnect(handle->wii);
                     exit(1);
             }
             change_position(handle);
             //show_status(handle->wii);
     }
     return 1;
}

int main(int argc,char **argv) {
     struct remoter handle;
     if (argc < 2) {
             fprintf(stderr, "Usage: test1 BDADDR\n");
             exit(1);
     }
     Evas_Object *   background;
     ecore_evas_init();

     ee = ecore_evas_software_x11_new(NULL, 0,  0, 0, WIDTH, HEIGHT);
     ecore_evas_title_set(ee, "Tick's Wii Toy");
//      ecore_evas_borderless_set(ee, 1);  // borderless
     ecore_evas_borderless_set(ee, 0);  // border
     ecore_evas_show(ee);


     evas = ecore_evas_get(ee);
     evas_font_path_append(evas, "fonts/");


     background = evas_object_rectangle_add(evas);
     evas_object_color_set(background,30,30,30,255);
     evas_object_resize(background, WIDTH, HEIGHT);
     evas_object_move( background,0 ,0 );
     evas_object_focus_set(background, 1);
     evas_object_show( background);

     handle.size = 64;
     handle.x=(WIDTH-handle.size)/2;
     handle.y=(HEIGHT-handle.size)/2;
     handle.o = evas_object_image_add(evas);
     evas_object_image_file_set (handle.o, "/home/tick/work/e17/icon.png" ,NULL);
     if (evas_object_image_load_error_get(handle.o)) {
             printf("Evas can't load PNG files. Check Evas has PNG\n");
             return 1;
     }
     evas_object_color_set(handle.o,255,255,255,128);
     evas_object_move(handle.o, handle.x,handle.y);
     evas_object_resize(handle.o,handle.size,handle.size);
     evas_object_image_fill_set(handle.o, 0, 0, handle.size, handle.size);
     evas_object_show(handle.o);

     printf("Please press 1+2 to connect Wii remote!!\n");
     handle.wii = wiimote_open(argv[1]);
     if (!handle.wii) {
             fprintf(stderr, "unable to open wiimote:\n");
             exit(1);
     }
     printf("Connecting.......\n");
     set_wiiremote(handle.wii);
     ecore_timer_add(.01,scan_wii_event, &handle);
     ecore_main_loop_begin();

     return 0;
}

使用:
1．先下 /etc/init.d/bluetooth start 打開bluetooth
2．按下 Wii remote 的 1+2 鍵
3．當 Wii remote 的Led 還在閃時，做 hcitool scan 找出你的 remote bdaddr
4． compile 完程式後，打 ./wii_toy 00:1A:E9:3B:CA:49 <--- 每個人的 wii remote 不一樣 就可以玩了

tick@tock:~/work/e17>hcitool scan
Scanning ...
     00:1A:E9:3B:CA:49       Nintendo RVL-CNT-01
tick@tock:~/work/e17>gcc `pkg-config --libs ecore-evas evas` -I/usr/local/include/libcwiimote-0.4.0/libcwiimote/ -lcwiimote -lbluetooth -Wall -pipe -D_ENABLE_TILT -D_ENABLE_FORCE  -g2 -o wii_toy wii_toy.c
tick@tock:~/work/e17>./wii_toy 00:1A:E9:3B:CA:49
Please press 1+2 to connect Wii remote!!
Connecting.......

有圖有真象

學習 Evas

這陣子開始需要用 Evas 寫一些東西…
個人覺得學一個 library 最快的方法就是去真的拿它去寫程式。
如我的一個好友常說的：學中作，作中學 ^^
所以就寫了支小小的玩具… 和大家分享…


亂畫一個方塊，設定一個重力場，和一個 boundary反彈機制. ( 和一些阻泥 (mark 掉了)) 加上一個色彩空間的旋轉。就玩起來了 ^^

程式:

Filename: toy.c

#include <Ecore_Evas.h>
#include <Ecore.h>
#include <stdlib.h>
#include <stdio.h>
#include <math.h>

#define WIDTH 400
#define HEIGHT 400

Ecore_Evas  *   ee;
Evas        *   evas;
Evas_Object *   base_rect;

double rotation[3][3] = { {0 , 0 , 1},
                          {1, 0, 0}, 
                          {0   , 1, 0}
};

struct bouncer {
        Evas_Object *o;
        int w,h;
        double xs,ys;
        double x,y;
        double color[3];
}; 

inline void change_color(struct bouncer *bounce) {
        double X[3];
        int i,j;
        int R,G,B;
        for (i=0;i<3;i++) {
                X[i]=bounce->color[i];
                bounce->color[i]=0;
        }
        for (i=0;i<3;i++) {
                for (j=0;j<3;j++) {
                        bounce->color[i] += rotation[i][j]*X[j];
                }
        }
        R=bounce->color[0] < 0 ? bounce->color[0] + 255: bounce->color[0];
        G=bounce->color[1] < 0 ? bounce->color[1] + 255: bounce->color[1];
        B=bounce->color[2] < 0 ? bounce->color[2] + 255: bounce->color[2];
        evas_object_color_set( bounce->o , R, G, B, 255);
}

inline void center(struct bouncer *bounce,double *x,double *y) {
        *x = bounce->x + bounce->w/2;
        *y = bounce->y + bounce->h/2;
}

inline void grav(struct bouncer *bounce) {
        const double G=300;
        double Gx,Gy,Gs;
        double x,y;
        double dist;
        center(bounce,&x,&y);

        dist = pow(pow(WIDTH/2-x,2) + pow(HEIGHT/2-y,2),0.5);
        Gs = G/pow(dist,2);
        Gx = (WIDTH/2 - x)/dist;
        Gy = (HEIGHT/2 -y)/dist;
        Gx = Gx * Gs;
        Gy = Gy * Gs;

        bounce->xs += Gx;
        bounce->ys += Gy;

        // Slow down~~
        //bounce->xs = abs(bounce->xs) > 13 ? bounce->xs *(1/ pow(bounce->xs-10,2)): bounce->xs;
        //bounce->ys = abs(bounce->ys) > 13 ? bounce->ys *(1/ pow(bounce->ys-10,2)): bounce->ys;
        printf ("x=%2.2f y=%2.2f dist=%4.2f Gs=%2.2f Gx=%2.2f Gy=%2.2f xs=%2.2f ys=%2.2f\n",x,y,dist,Gs,Gx,Gy,bounce->xs,bounce->ys);
}
inline void calculate_pos(struct bouncer *bounce) {
        grav(bounce);
        bounce->x += bounce->xs;
        bounce->y += bounce->ys;

        // bounce 
        bounce->xs = bounce->x >=0 ?  bounce->x + bounce->w <= WIDTH ? bounce->xs : -bounce->xs : -bounce->xs; 
        bounce->ys = bounce->y >=0 ? bounce->y + bounce->h <= HEIGHT? bounce->ys : - bounce->ys : - bounce->ys;
}

int move(void *data) {
        struct bouncer *bounce =(struct bouncer *)data;
        calculate_pos(bounce);
        evas_object_move(bounce->o,bounce->x,bounce->y);
        change_color(bounce);
        return 1;
}

int main() {
        struct bouncer bounce;
        ecore_evas_init();

        ee = ecore_evas_software_x11_new(NULL, 0,  0, 0, WIDTH, HEIGHT);
        ecore_evas_title_set(ee, "Tick's Evas Study");
//      ecore_evas_borderless_set(ee, 1);  // borderless
        ecore_evas_borderless_set(ee, 0);  // border
        ecore_evas_show(ee);


        evas = ecore_evas_get(ee);
        evas_font_path_append(evas, "fonts/");


        bounce.o = evas_object_rectangle_add(evas);
        bounce.w=bounce.h= (double)WIDTH/4;
        bounce.x=(double)(WIDTH - bounce.w)/3;
        bounce.y=(double)(HEIGHT-  bounce.h)/6;
        bounce.xs=-1.1; bounce.ys=1.1;
        bounce.color[0]=128;
        bounce.color[1]=64;
        bounce.color[2]=255;
        change_color(&bounce);
        evas_object_resize( bounce.o,  bounce.w,  bounce.h);
        evas_object_move( bounce.o,bounce.x,bounce.y);
        evas_object_show( bounce.o);

        ecore_timer_add((double)0.01,move,&bounce);

        ecore_main_loop_begin();

        return 0;
}

codecovert

Covert C code to Google prettyprint format

Filename: /usr/local/bin/codecovert

#!/bin/bash
for FF in $@;
do
      if [ -e $FF ];then
              echo Filename: $FF
              echo "<pre class=\"prettyprint\">"
              sed    -e 's/&/\&amp;/g'  -e 's/</\&lt;/g' -e 's/>/\&gt;/g'   $FF
              echo "</pre>"
      fi
      echo
done

Hello world

BITS 32

;section .text
;global _start
;_start:
jmp short two

one:
pop ecx  ; using the db
; write
xor eax,eax
mov al, 4
xor ebx,ebx
mov bl, 1
xor edx, edx
mov dl, 13
int 0x80

;exit
xor eax,eax
mov al, 1
xor ebx, ebx
int 0x80

two:
call one
db      "Hello_World!!"

Warning of "system" and "pipe"

I chatted with my friend about some security issues days before. I had mentioned about the function call "system" and "pipe" shall be avoid in many cases. It's very simple idea, but as I know many programmers even do not know it's very dangerous.
Please NEVER NEVER NEVER use this function to important programs.
NEVER allow user to touch the args, or PATH.
Please~~~

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
void fake_ls(int args,char **argv) {
     char buf[50];
     char *ptr=buf;
     int i;
     sprintf(buf,"ls");
     for (i=1;i<args;i++) {
             ptr = buf + strlen(buf);
             sprintf(ptr," %s",argv[i]);
     }
     printf("The command you send is: '%s'\n",buf);
     system(buf);
}
int main (int args,char **argv) {
     printf("argv=%p\n",argv);
     fake_ls(args,argv);
}

you can use the following argument to execute
extra command: "-al\;cat /etc/passwd"
It's very easy to see how terrible it is. :-)