jeff

//gcc  `pkg-config enlightenment --cflags` -c zoom2.c
//gcc  zoom2.o `pkg-config enlightenment --libs` `pkg-config ecore-input --libs`

#include <Eina.h>
#include <Ecore.h>
#include <Ecore_X.h>
#include <Ecore_Evas.h>
#include <stdio.h>
#include <math.h>

typedef struct _Item Item;

struct _Item
{
  Evas_Object *o;
  int posx;
  int posy;
  int mx;
  int my;
};

#define SIZE  8
#define WIDTH 600
#define HEIGHT 600
#define OFFSET 100

static Evas_Object *move, *o;
static Eina_List *items = NULL;
static float zoom = 2.0;
static float range = 100.0;
static Ecore_Idle_Enterer *idler = NULL;
static int mx = 0;
static int my = 0;
static int changed = 0;

static void
_mouse_down_cb(void *data, Evas *evas, Evas_Object *obj, void *event_info)
{
   Evas_Event_Mouse_Wheel *e = event_info;

   if (e->z< 0)
     zoom += 0.1;
   else if (e->z > 0)
     zoom -= 0.1;

   changed = 1;
}

static double
_zoom(double dist)
{
   if (dist >= range)
     {
        return range * zoom;
     }
   else if (dist <= -range)
     {
        return -range * zoom;
     }

   return sin(M_PI/2.0 * dist/range) * range * zoom;
}

static double arc = 0.0;
static int dir = 1;

static Eina_Bool
_redraw(void *data)
{
   Item *it;
   Eina_List *l;

   double posx1, posx2, posy1, posy2;

   /* if (!changed)
    *   return EINA_TRUE; */

   if (dir)
     {
        zoom += 0.1;
        if (zoom > 5)
          dir = 0;
     }
   else
     {
        zoom -= 0.1;
        if (zoom <= 0)
          dir = 1;
     }

   mx = OFFSET + WIDTH/2 +  2 * range * sin(arc);
   my = OFFSET + HEIGHT/2 + 2 * range * cos(arc);
   arc += 0.03;


   EINA_LIST_FOREACH(items, l, it)
     {
        int x1 = it->posx + SIZE/2;
        int y1 = it->posy + SIZE/2;

        double dist1 = sqrt ((x1 - mx) * (x1 - mx) + ((y1 - my) * (y1 - my)));

        double ndist1 = _zoom(dist1);

        posx1 = x1 - SIZE/2 + (x1 - mx) / dist1 * ndist1;
        posy1 = y1 - SIZE/2 + (y1 - my) / dist1 * ndist1;

        posx2 = x1 + SIZE/2 + (x1 - mx) / dist1 * ndist1;
        posy2 = y1 + SIZE/2 + (y1 - my) / dist1 * ndist1;

        evas_object_move(it->o, posx1, posy1);

        evas_object_resize(it->o, (posx2 - posx1) - 0.5, (posy2 - posy1) - 0.5);
     }

   changed = 0;

   return EINA_TRUE;
}

static void
_mouse_move_cb(void *data, Evas *evas, Evas_Object *obj, void *event_info)
{
   Evas_Event_Mouse_Move *e = event_info;

   mx = e->cur.canvas.x;
   my = e->cur.canvas.y;

   changed = 1;

   _redraw(NULL);
}

int main(int argc, char *argv[])
{
   Ecore_Evas *ee;
   Evas *e;
   int k, j;
   Evas_Object *bg;

   ecore_init();
   ecore_evas_init();

   ee = ecore_evas_software_x11_new(NULL, 0, 10, 10, WIDTH +200, HEIGHT + 200);

   /* ecore_evas_alpha_set(ee, 1); */
   /* ecore_evas_borderless_set(ee, 1); */
   ecore_evas_name_class_set(ee, "BOX", "TEST");
   ecore_evas_show(ee);
   e = ecore_evas_get(ee);

   bg = evas_object_rectangle_add(e);
   evas_object_resize(bg, WIDTH + 200, HEIGHT + 200);
   evas_object_color_set(bg, 20, 20, 20, 255);
   /* evas_object_layer_set(bg, 255);  */
   evas_object_show(bg);

   evas_object_event_callback_add(bg, EVAS_CALLBACK_MOUSE_MOVE, _mouse_move_cb, bg);
   evas_object_event_callback_add(bg, EVAS_CALLBACK_MOUSE_WHEEL, _mouse_down_cb, bg);

   Item *item;

   Evas_Object *oo;

   for (k = 0; k < WIDTH/SIZE+1; k++)
     {
    for (j = 0; j < HEIGHT/SIZE+1; j++)
      {
         item = calloc(1, sizeof(Item));

         oo = evas_object_rectangle_add(e);
         evas_object_resize(oo, SIZE, SIZE);
         evas_object_color_set(oo, 255 - 5 * k, 5 * j-k, 5 * k, 220);
         evas_object_show(oo);
             evas_object_pass_events_set(oo, EINA_TRUE);

         item->o = oo;
         item->posx = OFFSET + k * SIZE;
         item->posy = OFFSET + j * SIZE;
         evas_object_move(oo, item->posx, item->posy);
         items = eina_list_append(items, item);
      }
     }

   ecore_timer_add(0.0001, _redraw, NULL);

   ecore_main_loop_begin();


   EINA_LIST_FREE(items, item)
     free(item);

   evas_object_del(bg);

   ecore_evas_shutdown();
   ecore_shutdown();
   return 0;
}