screen_getbycoord: Change definition of 'closest screen'

Instead of comparing only the top-left corner of the screen to the provided
coordinate, this now compares the screen in a more intuitive way, e.g.
coordinates inside of the screen have a distance of zero.

Signed-off-by: Uli Schlachter <psychon@znc.in>
This commit is contained in:
Uli Schlachter 2015-10-10 20:10:23 +02:00
parent b34a653448
commit d4168f3c36

View file

@ -35,7 +35,6 @@
#include "objects/client.h"
#include "objects/drawin.h"
#include <math.h>
#include <stdio.h>
#include <xcb/xcb.h>
@ -285,6 +284,38 @@ screen_scan(void)
screen_scan_x11();
}
/** Return the squared distance of the given screen to the coordinates.
* \param screen The screen
* \param x X coordinate
* \param y Y coordinate
* \return Squared distance of the point to the screen.
*/
static unsigned int
screen_get_distance_squared(screen_t *s, int x, int y)
{
int sx = s->geometry.x, sy = s->geometry.y;
int sheight = s->geometry.height, swidth = s->geometry.width;
unsigned int dist_x, dist_y;
/* Calculate distance in X coordinate */
if (x < sx)
dist_x = sx - x;
else if (x < sx + swidth)
dist_x = 0;
else
dist_x = x - sx - swidth;
/* Calculate distance in Y coordinate */
if (y < sy)
dist_y = sy - y;
else if (y < sy + sheight)
dist_y = 0;
else
dist_y = y - sy - sheight;
return dist_x * dist_x + dist_y * dist_y;
}
/** Return the first screen number where the coordinates belong to.
* \param x X coordinate
* \param y Y coordinate
@ -298,15 +329,15 @@ screen_getbycoord(int x, int y)
return *s;
/* No screen found, find nearest screen. */
screen_t * nearest_screen = globalconf.screens.tab[0];
int nearest_dist = INT_MAX;
screen_t *nearest_screen = globalconf.screens.tab[0];
unsigned int nearest_dist = UINT_MAX;
foreach(s, globalconf.screens)
{
int dist = sqrt(pow((*s)->geometry.x - x, 2) + pow((*s)->geometry.y - y, 2));
if( dist < nearest_dist )
unsigned int dist_sq = screen_get_distance_squared(*s, x, y);
if(dist_sq < nearest_dist)
{
nearest_dist = dist;
nearest_screen = (*s);
nearest_dist = dist_sq;
nearest_screen = *s;
}
}
return nearest_screen;