Graphics

QNX SDP 7.1 includes the Screen Graphics Subsystem.

If you're migrating your Screen applications from QNX SDP 7.0:

• You need to rebuild your binaries.

• In QNX SDP 7.1, you must now call the screen_register_event() function before you call screen_notify() to register the event for asynchronous notification. Otherwise, you won't receive any asynchronous notifications.

  The screen_register_event() function registers a sigevent that screen_notify() uses.

  When you are no longer using asynchronous notifications, you need to disable the notifications and then remove the event registration. Ensure that the registered event is no longer in use by any Screen object before removing the event registration by calling screen_unregister_event(). We recommend that you call screen_unregister_event() only after you've disabled asynchronous notifications that are using the event you're unregistering. If you remove the event registration while you still have asynchronous notifications using that event enabled, you may not receive any notifications. To disable asynchronous notifications, call screen_notify() with the event argument set to NULL, or its type set to SIGEV_NONE for those notifications that were enabled.

• In QNX SDP 7.1, when you're using external buffers and the SCREEN_PROPERTY_FD property to assign the file descriptor to this externally allocated memory, you must now:

  • call shm_ctl() to set the SHMCTL_SEAL flag to prevent the shared memory object from being modified.
  • ensure that the SHMCTL_REVOCABLE flag is NOT set on your shared memory object. You can call shm_ctl() with the SHMCTL_GET_FLAGS flag to verify which flags have been set on the object that you're using. If the SHMCTL_REVOCABLE flag has been set, you can't associate this object with your buffer.
  See “Buffers” Buffers chapter from the Screen Developer's Guide.

• In QNX SDP 7.1, the following Screen utilities are now in the addon package, SDP 7.1 Screen Utilities:

  • screencmd
  • screeninfo
• In QNX SDP 7.1, you'll require the drm-vmwgfx utility for the purpose of working in virtual target environments in VMWare.
• In QNX SDP 7.1, if blit-config is set to vivante in your graphics.conf file, you will need to rename it to nxp-g2d.