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#include "libi3.h"
#include <math.h>
extern xcb_screen_t *root_screen;
/*
* Convert a logical amount of pixels (e.g. 2 pixels on a “standard” 96 DPI
* screen) to a corresponding amount of physical pixels on a standard or retina
* screen, e.g. 5 pixels on a 227 DPI MacBook Pro 13" Retina screen.
*
*/
int logical_px(const int logical) {
const int dpi = (double)root_screen->height_in_pixels * 25.4 /
(double)root_screen->height_in_millimeters;
/* There are many misconfigurations out there, i.e. systems with screens
* whose dpi is in fact higher than 96 dpi, but not significantly higher,
* so software was never adapted. We could tell people to reconfigure their
* systems to 96 dpi in order to get the behavior they expect/are used to,
* but since we can easily detect this case in code, let’s do it for them.
*/
if ((dpi / 96.0) < 1.25)
return logical;
return ceil((dpi / 96.0) * logical);
}
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