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+.. default-domain:: c
+.. highlight:: c
+Handling Events
+Events are sent to a view when it has received user input,
+must be drawn, or in other situations that may need to be handled such as resizing.
+Events are sent to the event handler as a :union:`PuglEvent` union.
+The ``type`` field defines the type of the event and which field of the union is active.
+The application must handle at least :enumerator:`PUGL_CONFIGURE <PuglEventType.PUGL_CONFIGURE>`
+and :enumerator:`PUGL_EXPOSE <PuglEventType.PUGL_EXPOSE>` to draw anything,
+but there are many other :enum:`event types <PuglEventType>`.
+For example, a basic event handler might look something like this:
+.. code-block:: c
+ static PuglStatus
+ onEvent(PuglView* view, const PuglEvent* event)
+ {
+ MyApp* app = (MyApp*)puglGetHandle(view);
+ switch (event->type) {
+ return setupGraphics(app);
+ return teardownGraphics(app);
+ return resize(app, event->configure.width, event->configure.height);
+ return draw(app, view);
+ case PUGL_CLOSE:
+ return quit(app);
+ return onButtonPress(app, view, event->button);
+ default:
+ break;
+ }
+ return PUGL_SUCCESS;
+ }
+Using the Graphics Context
+Note that Pugl uses a different drawing model than many libraries,
+particularly those designed for game-style main loops like `SDL <https://libsdl.org/>`_ and `GLFW <https://www.glfw.org/>`_.
+In that style of code, drawing is performed imperatively in the main loop,
+but with Pugl, the application must draw only while handling an expose event.
+This is because Pugl supports event-driven applications that only draw the damaged region when necessary,
+and handles exposure internally to provide optimized and consistent behavior across platforms.
+Cairo Context
+A Cairo context is created for each :struct:`PuglEventExpose`,
+and only exists during the handling of that event.
+Null is returned by :func:`puglGetContext` at any other time.
+OpenGL Context
+The OpenGL context is only active during the handling of these events:
+- :struct:`PuglEventCreate`
+- :struct:`PuglEventDestroy`
+- :struct:`PuglEventConfigure`
+- :struct:`PuglEventExpose`
+As always, drawing is only possible during an expose.
+Vulkan Context
+With Vulkan, the graphics context is managed by the application rather than Pugl.
+However, drawing must still only be performed during an expose.