// setColorTemp changes the Xrandr colors to reflect the specified color temperature.
func setColorTemp(gammar, gammag, gammab float64) {
dpy := C.XOpenDisplay(nil)
screenCount := C.screenCount(dpy)
for screen := C.int(0); screen < screenCount; screen++ {
root := C.RootWindowMacro(dpy, screen)
res := C.XRRGetScreenResourcesCurrent(dpy, root)
for c := C.int(0); c < res.ncrtc; c++ {
crtcxid := C.crtcxid(res.crtcs, c)
size := C.XRRGetCrtcGammaSize(dpy, crtcxid)
crtc_gamma := C.XRRAllocGamma(size)
for i := C.int(0); i < size; i++ {
g := 65535.0 * float64(i) / float64(size)
C.ushortSet(C.ushortCast(unsafe.Pointer(crtc_gamma.red)), i, C.double(g*gammar))
C.ushortSet(C.ushortCast(unsafe.Pointer(crtc_gamma.green)), i, C.double(g*gammag))
C.ushortSet(C.ushortCast(unsafe.Pointer(crtc_gamma.blue)), i, C.double(g*gammab))
}
C.XRRSetCrtcGamma(dpy, crtcxid, crtc_gamma)
C.XFree(unsafe.Pointer(crtc_gamma))
}
C.XFree(unsafe.Pointer(res))
}
C.XCloseDisplay(dpy)
}
// SetColorTemp changes the Xrandr colors to reflect the specified color temperature.
func SetColorTemp(temp int) {
dpy := C.XOpenDisplay(nil)
screenCount := C.screenCount(dpy)
for screen := C.int(0); screen < screenCount; screen++ {
root := C.RootWindowMacro(dpy, screen)
res := C.XRRGetScreenResourcesCurrent(dpy, root)
if temp < 1000 || temp > 10000 {
temp = 6500
}
temp -= 1000
ratio := float64((temp-1000)%500) / 500.0
point := whitepoints[temp/500]
gammar := point.r*(1-ratio) + point.r*ratio
gammag := point.g*(1-ratio) + point.g*ratio
gammab := point.b*(1-ratio) + point.b*ratio
for c := C.int(0); c < res.ncrtc; c++ {
crtcxid := C.crtcxid(res.crtcs, c)
size := C.XRRGetCrtcGammaSize(dpy, crtcxid)
crtc_gamma := C.XRRAllocGamma(size)
for i := C.int(0); i < size; i++ {
g := 65535.0 * float64(i) / float64(size)
C.ushortSet(crtc_gamma.red, i, C.ushort(g*gammar))
C.ushortSet(crtc_gamma.green, i, C.ushort(g*gammag))
C.ushortSet(crtc_gamma.blue, i, C.ushort(g*gammab))
}
C.XRRSetCrtcGamma(dpy, crtcxid, crtc_gamma)
C.XFree(unsafe.Pointer(crtc_gamma))
}
}
}