Check null objects

[guile-irrlicht.git] / irrlicht / device.scm

diff --git a/irrlicht/device.scm b/irrlicht/device.scm
index 24b3f8b2ae2da537de781f6b59de166fd34f302e..04988d39602e24deb51ead3f2cce967fccbaa750 100644 (file)
--- a/irrlicht/device.scm
+++ b/irrlicht/device.scm
@@ -46,16 +46,13 @@
        "In procedure create-device: Wrong type argument (expecting <event-receiver>):"
        receiver))
 
-  (make <irrlicht-device>
-    #:irr-pointer
-    ((get-irrlicht-proc "createDevice")
-     device-type
-     window-size
-     bits
-     fullscreen
-     stencilbuffer
-     vsync
-     receiver)))
+  (let* ((createDevice (get-irrlicht-proc "createDevice"))
+         (device-pointer (createDevice device-type window-size bits fullscreen stencilbuffer
+                                       vsync receiver)))
+    (cond ((null-pointer? device-pointer)
+           (error "In procedure create-device: Device cannot be created"))
+          (else
+           (make <irrlicht-device> #:irr-pointer device-pointer)))))
 
 (define-method (get-cursor-control (device <irrlicht-device>))
   (let ((getCursorControl (get-irrlicht-proc "getCursorControl" device)))
@@ -80,6 +77,10 @@
   (make <video-driver>
     #:irr-pointer ((get-irrlicht-proc "getVideoDriver" device) device)))
 
+(define-method (is-window-active? (device <irrlicht-device>))
+  (let ((isWindowActive (get-irrlicht-proc "isWindowActive" device)))
+    (isWindowActive device)))
+
 (define-method (run (device <irrlicht-device>))
   ((get-irrlicht-proc "run" device) device))
 
@@ -87,5 +88,9 @@
   ((get-irrlicht-proc "setWindowCaption" device)
    device text))
 
+(define-method (yield-device (device <irrlicht-device>))
+  (let ((yield (get-irrlicht-proc "yield" device)))
+    (yield device)))
+
 (export create-device get-cursor-control get-file-system get-gui-environment get-scene-manager
-        get-video-driver run set-window-caption!)
+        get-video-driver is-window-active? run set-window-caption! yield-device)