Page 1 of 1
How to get the DPI value?
Posted: Thu Sep 24, 2015 8:27 pm
by Little John
Hi,
unfortunately I'm not familiar with Linux API programming.
I just tried the following (on Linux Mint 17.2 Cinnamon with PB 5.40 beta 6) in order to get the DPI value of the current screen:
Code: Select all
ImportC ""
gdk_screen_get_resolution (*screen.GdkScreen)
EndImport
Define *screen.GdkScreen
*screen = gdk_screen_get_default_()
Debug *screen
Debug gdk_screen_get_resolution(*screen)
But that doesn't work, the output is
0
0
Any hints?
Re: How to get the DPI value?
Posted: Thu Sep 24, 2015 9:07 pm
by Keya
You just need to call gdk_init first
as i only discovered last week heehee
PB calls that automatically for you when you create a new window, and also i think when you use a requester like messagebox - im assuming just once at program startup.
It's usually called like: gdk_init(argc,argv)
I havent figured out yet how to correctly pass argc and argv, but gdk_init_(0,0) works
for related example see my
Hello World GTK SDK demo, although in that one im calling gtk_init instead of gdk_init as im only using gtk_ funcs
Re: How to get the DPI value?
Posted: Fri Sep 25, 2015 10:02 am
by Little John
That's a step into the right direction.
Thank you.
Now I have this:
Code: Select all
ImportC ""
gdk_screen_get_resolution(*screen.GdkScreen)
EndImport
Define *screen.GdkScreen
gdk_init_(0, 0)
*screen = gdk_screen_get_default_()
If *screen
Debug gdk_screen_get_resolution(*screen)
EndIf
The output is:
1 
That value should be somewhat bigger, I think.
Re: How to get the DPI value?
Posted: Fri Sep 25, 2015 10:21 am
by Keya
Hrm, well
https://developer.gnome.org/gdk3/stable ... resolution says it returns a Double, but even with that it's still returning just "1.0" on my Mint.
(Unless the way it's currently declared = Integer and not Double?)
But the
doc suggests it's normally 96, or -1 if not set ...
*screen\resolution = 0 also
Re: How to get the DPI value?
Posted: Fri Sep 25, 2015 10:27 am
by Keya
Yes, it's just the declaration ... needs to be declared as Double:
gdk_screen_get_resolution
.d (*screen.GdkScreen)
Then we get the correct return value of -1.0 (unset) ... which still isn't much help heehee
Re: How to get the DPI value?
Posted: Fri Sep 25, 2015 3:03 pm
by Oma
Hi,
the current dpi-value you could get this way:
Code: Select all
ImportC ""
g_object_get_property(*widget.GtkWidget, property.p-utf8, *gval)
g_value_get_uint(gval)
EndImport
Global.i gEvent, gQuit
#G_TYPE_UINT = 28
Procedure GetCurrentDpi()
Protected gVal.GValue
Protected.i Ret
g_value_init_(@gval, #G_TYPE_UINT)
g_object_get_property(gtk_settings_get_default_(), "gtk-xft-dpi", @gval)
Ret= g_value_get_uint(@gval)
g_value_unset_(@gval)
ProcedureReturn Ret
EndProcedure
If OpenWindow(0, 300, 200, 500, 200, "Get current dpi", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
Debug GetCurrentDpi()/1024
Repeat
If WaitWindowEvent() = #PB_Event_CloseWindow
gQuit= #True
EndIf
Until gQuit
EndIf
If you want further information about the monitor:
Code: Select all
EnableExplicit
ImportC ""
gtk_widget_get_window(*widget.GtkWidget)
EndImport
ImportC ""
gdk_window_get_screen(*Window)
gdk_screen_get_monitor_height_mm(*screen.GdkScreen, monitor_num)
gdk_screen_get_monitor_width_mm(*screen.GdkScreen, monitor_num)
gdk_screen_get_monitor_plug_name(*screen.GdkScreen, monitor_num)
EndImport
; Object constants
#MainWin = 0
#But1 = 0
#WinX=300
#WinY=200
#WinW=200
#WinH=200
Global.i gEvent, gQuit
Global *screen.GdkScreen
Procedure.i GetGdkWindow(Window)
ProcedureReturn gtk_widget_get_window(WindowID(Window))
EndProcedure
Procedure GetWindowScreen(Window)
ProcedureReturn gdk_window_get_screen(GetGdkWindow(Window))
EndProcedure
If OpenWindow(#MainWin, #WinX, #WinY, #WinW, #WinH, "Get Screen data", #PB_Window_SystemMenu | #PB_Window_ScreenCentered | #PB_Window_MaximizeGadget | #PB_Window_MinimizeGadget)
ButtonGadget(#But1, 5, 5, 190, 26, "Debug screen data")
Repeat
gEvent= WaitWindowEvent()
Select gEvent
Case #PB_Event_CloseWindow
gQuit= #True
Case #PB_Event_Gadget
If EventGadget()= #But1
*screen= GetWindowScreen(#MainWin)
Debug "Screen-adress : " + Str(*screen)
Debug "Screen-index : " + Str(gdk_screen_get_number_(*screen))
Debug "Display-Adress from Screen : " + Str(gdk_screen_get_display_(*screen))
Debug "Screen width : " + Str(gdk_screen_get_width_(*screen))
Debug "Screen height : " + Str(gdk_screen_get_height_(*screen))
Debug "Screen width [mm] : " + Str(gdk_screen_get_width_mm_(*screen))
Debug "Screen height [mm] : " + Str(gdk_screen_get_height_mm_(*screen))
Debug "Monitor number from Screen : " + Str(gdk_screen_get_n_monitors_(*screen))
Debug "Monitor width [mm] from Screen : " + Str(gdk_screen_get_monitor_width_mm(*screen, 0))
Debug "Monitor height [mm] from Screen: " + Str(gdk_screen_get_monitor_height_mm(*screen, 0))
Debug "Monitor plug name from Screen : " + PeekS(gdk_screen_get_monitor_plug_name(*screen, 0), -1, #PB_Ascii)
EndIf
EndSelect
Until gQuit
EndIf
Bye, Charly
Re: How to get the DPI value?
Posted: Fri Sep 25, 2015 3:46 pm
by Little John
Hi Charly,
I was hoping that you would chime in here.
Great!
Your code works fine on my system, Thank you very much!