1 #ifndef DALI_INTEGRATION_CORE_H
2 #define DALI_INTEGRATION_CORE_H
5 * Copyright (c) 2019 Samsung Electronics Co., Ltd.
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
22 #include <cstdint> // uint32_t
25 #include <dali/public-api/common/dali-common.h>
26 #include <dali/integration-api/context-notifier.h>
27 #include <dali/integration-api/core-enumerations.h>
28 #include <dali/integration-api/resource-policies.h>
45 class GlSyncAbstraction;
46 class PlatformAbstraction;
48 class RenderController;
55 * The reasons why further updates are required.
57 namespace KeepUpdating
61 NOT_REQUESTED = 0, ///< Zero means that no further updates are required
62 STAGE_KEEP_RENDERING = 1<<1, ///< - Stage::KeepRendering() is being used
63 ANIMATIONS_RUNNING = 1<<2, ///< - Animations are ongoing
64 MONITORING_PERFORMANCE = 1<<3, ///< - The --enable-performance-monitor option is being used
65 RENDER_TASK_SYNC = 1<<4 ///< - A render task is waiting for render sync
70 * The status of the Core::Update operation.
80 : keepUpdating(false),
81 needsNotification(false),
82 surfaceRectChanged(false),
83 secondsFromLastFrame( 0.0f )
90 * Query whether the Core has further frames to update & render e.g. when animations are ongoing.
91 * @return A bitmask of KeepUpdating values
93 uint32_t KeepUpdating() { return keepUpdating; }
96 * Query whether the Core requires an Notification event.
97 * This should be sent through the same mechanism (e.g. event loop) as input events.
98 * @return True if an Notification event should be sent.
100 bool NeedsNotification() { return needsNotification; }
103 * Query wheter the default surface rect is changed or not.
104 * @return true if the default surface rect is changed.
106 bool SurfaceRectChanged() { return surfaceRectChanged; }
109 * This method is provided so that FPS can be easily calculated with a release version
111 * @return the seconds from last frame as float
113 float SecondsFromLastFrame() { return secondsFromLastFrame; }
117 uint32_t keepUpdating; ///< A bitmask of KeepUpdating values
118 bool needsNotification;
119 bool surfaceRectChanged;
120 float secondsFromLastFrame;
124 * The status of the Core::Render operation.
134 : needsUpdate( false ),
135 needsPostRender( false )
140 * Set whether update needs to run following a render.
141 * @param[in] updateRequired Set to true if an update is required to be run
143 void SetNeedsUpdate( bool updateRequired )
145 needsUpdate = updateRequired;
149 * Query the update status following rendering of a frame.
150 * @return True if update is required to be run
152 bool NeedsUpdate() const
158 * Sets if a post-render should be run.
159 * If nothing is rendered this frame, we can skip post-render.
160 * @param[in] postRenderRequired Set to True if post-render is required to be run
162 void SetNeedsPostRender( bool postRenderRequired )
164 needsPostRender = postRenderRequired;
168 * Queries if a post-render should be run.
169 * @return True if post-render is required to be run
171 bool NeedsPostRender() const
173 return needsPostRender;
178 bool needsUpdate :1; ///< True if update is required to be run
179 bool needsPostRender :1; ///< True if post-render is required to be run.
184 * Integration::Core is used for integration with the native windowing system.
185 * The following integration tasks must be completed:
187 * 1) Handle GL context creation, and notify the Core when this occurs.
189 * 2) Provide suspend/resume behaviour (see below for more details).
191 * 3) Run an event loop, for passing events to the Core e.g. multi-touch input events.
192 * Notification events should be sent after a frame is updated (see UpdateStatus).
194 * 4) Run a rendering loop, instructing the Core to render each frame.
195 * A separate rendering thread is recommended; see multi-threading options below.
197 * 5) Provide an implementation of the PlatformAbstraction interface, used to access platform specific services.
199 * 6) Provide an implementation of the GlAbstraction interface, used to access OpenGL services.
201 * Multi-threading notes:
203 * The Dali API methods are not reentrant. If you access the API from multiple threads simultaneously, then the results
204 * are undefined. This means that your application might segfault, or behave unpredictably.
206 * Rendering strategies:
208 * 1) Single-threaded. Call every Core method from the same thread. Event handling and rendering will occur in the same thread.
209 * This is not recommended, since processing input (slowly) can affect the smooth flow of animations.
211 * 2) Multi-threaded. The Core update & render operations can be processed in separate threads.
212 * See the method descriptions in Core to see which thread they should be called from.
213 * This is the recommended option, so that input processing will not affect the smoothness of animations.
214 * Note that the rendering thread must be halted, before destroying the GL context.
216 class DALI_CORE_API Core
222 * This object is used for integration with the native windowing system.
223 * @param[in] renderController The interface to an object which controls rendering.
224 * @param[in] platformAbstraction The interface providing platform specific services.
225 * @param[in] glAbstraction The interface providing OpenGL services.
226 * @param[in] glSyncAbstraction The interface providing OpenGL sync objects.
227 * @param[in] policy The data retention policy. This depends on application setting
228 * and platform support. Dali should honour this policy when deciding to discard
229 * intermediate resource data.
230 * @param[in] renderToFboEnabled Whether rendering into the Frame Buffer Object is enabled.
231 * @param[in] depthBufferAvailable Whether the depth buffer is available
232 * @param[in] stencilBufferAvailable Whether the stencil buffer is available
233 * @return A newly allocated Core.
235 static Core* New( RenderController& renderController,
236 PlatformAbstraction& platformAbstraction,
237 GlAbstraction& glAbstraction,
238 GlSyncAbstraction& glSyncAbstraction,
239 ResourcePolicy::DataRetention policy,
240 RenderToFrameBuffer renderToFboEnabled,
241 DepthBufferAvailable depthBufferAvailable,
242 StencilBufferAvailable stencilBufferAvailable );
245 * Non-virtual destructor. Core is not intended as a base class.
250 * Initialize the core
254 // GL Context Lifecycle
257 * Get the object that will notify the application/toolkit when context is lost/regained
259 ContextNotifierInterface* GetContextNotifier();
262 * Notify the Core that the GL context has been created.
263 * The context must be created before the Core can render.
264 * Multi-threading note: this method should be called from the rendering thread only
265 * @post The Core is aware of the GL context.
267 void ContextCreated();
270 * Notify the Core that that GL context is about to be destroyed.
271 * The Core will free any previously allocated GL resources.
272 * Multi-threading note: this method should be called from the rendering thread only
273 * @post The Core is unaware of any GL context.
275 void ContextDestroyed();
278 * Notify the Core that the GL context has been re-created, e.g. after ReplaceSurface
281 * In the case of ReplaceSurface, both ContextToBeDestroyed() and ContextCreated() will have
282 * been called on the render thread before this is called on the event thread.
284 * Multi-threading note: this method should be called from the main thread
286 void RecoverFromContextLoss();
289 * Notify the Core that the GL surface has been resized.
290 * This should be done at least once i.e. after the first call to ContextCreated().
291 * The Core will use the surface size for camera calculations, and to set the GL viewport.
292 * Multi-threading note: this method should be called from the main thread
293 * @param[in] surface The resized surface
295 void SurfaceResized( Integration::RenderSurface* surface );
300 * Notify Core that the scene has been created.
305 * Queue an event with Core.
306 * Pre-processing of events may be beneficial e.g. a series of motion events could be throttled, so that only the last event is queued.
307 * Multi-threading note: this method should be called from the main thread.
308 * @param[in] event The new event.
310 void QueueEvent(const Event& event);
313 * Process the events queued with QueueEvent().
314 * Multi-threading note: this method should be called from the main thread.
315 * @pre ProcessEvents should not be called during ProcessEvents.
317 void ProcessEvents();
320 * The Core::Update() method prepares a frame for rendering. This method determines how many frames
321 * may be prepared, ahead of the rendering.
322 * For example if the maximum update count is 2, then Core::Update() for frame N+1 may be processed
323 * whilst frame N is being rendered. However the Core::Update() for frame N+2 may not be called, until
324 * the Core::Render() method for frame N has returned.
325 * @return The maximum update count (>= 1).
327 uint32_t GetMaximumUpdateCount() const;
330 * Update the scene for the next frame. This method must be called before each frame is rendered.
331 * Multi-threading notes: this method should be called from a dedicated update-thread.
332 * The update for frame N+1 may be processed whilst frame N is being rendered.
333 * However the update-thread must wait until frame N has been rendered, before processing frame N+2.
334 * After this method returns, messages may be queued internally for the main thread.
335 * In order to process these messages, a notification is sent via the main thread's event loop.
336 * @param[in] elapsedSeconds Number of seconds since the last call
337 * @param[in] lastVSyncTimeMilliseconds The last vsync time in milliseconds
338 * @param[in] nextVSyncTimeMilliseconds The time of the next predicted VSync in milliseconds
339 * @param[out] status showing whether further updates are required. This also shows
340 * whether a Notification event should be sent, regardless of whether the multi-threading is used.
341 * @param[in] renderToFboEnabled Whether rendering into the Frame Buffer Object is enabled.
342 * @param[in] isRenderingToFbo Whether this frame is being rendered into the Frame Buffer Object.
344 void Update( float elapsedSeconds,
345 uint32_t lastVSyncTimeMilliseconds,
346 uint32_t nextVSyncTimeMilliseconds,
347 UpdateStatus& status,
348 bool renderToFboEnabled,
349 bool isRenderingToFbo );
352 * Render the next frame. This method should be preceded by a call up Update.
353 * Multi-threading note: this method should be called from a dedicated rendering thread.
354 * @pre The GL context must have been created, and made current.
355 * @param[out] status showing whether update is required to run.
356 * @param[in] forceClear force the Clear on the framebuffer even if nothing is rendered.
358 void Render( RenderStatus& status, bool forceClear );
361 * @brief Register a processor
363 * Note, Core does not take ownership of this processor.
364 * @param[in] processor The process to register
366 void RegisterProcessor( Processor& processor );
369 * @brief Unregister a processor
370 * @param[in] processor The process to unregister
372 void UnregisterProcessor( Processor& processor );
377 * Private constructor; see also Core::New()
382 * Undefined copy-constructor.
383 * This avoids accidental calls to a default copy-constructor.
384 * @param[in] core A reference to the object to copy.
386 Core(const Core& core);
389 * Undefined assignment operator.
390 * This avoids accidental calls to a default assignment operator.
391 * @param[in] rhs A reference to the object to copy.
393 Core& operator=(const Core& rhs);
397 Internal::Core* mImpl;
401 } // namespace Integration
405 #endif // DALI_INTEGRATION_CORE_H