Module: Doom::Platform::GosuWindow::SDLKeyboardGrab

Defined in:
lib/doom/platform/gosu_window.rb

Overview

SDL2 keyboard grab via Gosu’s bundled SDL – prevents OS key interception

Class Method Summary collapse

Class Method Details

.grab! ⇒ Object 



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# File 'lib/doom/platform/gosu_window.rb', line 30

def self.grab!
  return unless @ready
  @set_kb_grab.call(@shared_window.call, 1)
end

.release! ⇒ Object 



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# File 'lib/doom/platform/gosu_window.rb', line 35

def self.release!
  return unless @ready
  @set_kb_grab.call(@shared_window.call, 0)
end

.setup ⇒ Object 



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# File 'lib/doom/platform/gosu_window.rb', line 12

def self.setup
  require "fiddle"
  gosu_spec = Gem.loaded_specs["gosu"]
  lib_ext = RbConfig::CONFIG["DLEXT"] || "so"
  bundle = File.join(gosu_spec.full_gem_path, "lib", "gosu.#{lib_ext}")
  @lib = Fiddle.dlopen(bundle)
  @shared_window = Fiddle::Function.new(
    @lib["_ZN4Gosu13shared_windowEv"], [], Fiddle::TYPE_VOIDP
  )
  @set_kb_grab = Fiddle::Function.new(
    @lib["SDL_SetWindowKeyboardGrab"],
    [Fiddle::TYPE_VOIDP, Fiddle::TYPE_INT], Fiddle::TYPE_VOID
  )
  @ready = true
rescue
  @ready = false
end