1 #ifndef DALI_RENDER_TASK_H
2 #define DALI_RENDER_TASK_H
5 * Copyright (c) 2020 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/math/viewport.h>
26 #include <dali/public-api/object/handle.h>
27 #include <dali/public-api/object/property-index-ranges.h>
28 #include <dali/public-api/signals/dali-signal.h>
33 * @addtogroup dali_core_rendering_effects
39 class FrameBufferImage;
43 namespace Internal DALI_INTERNAL
49 * @brief RenderTasks describe how the Dali scene should be rendered.
51 * The Scene provides access to an ordered list of render-tasks.
53 * Each RenderTask must specify the source actors to be rendered, and a camera actor from
54 * which the scene is viewed.
56 * RenderTasks may optionally target a frame-buffer, otherwise the default GL surface is used;
57 * typically this is a window provided by the native system.
59 * By default Dali provides a single RenderTask, which renders the entire actor hierarchy using
60 * a default camera actor and GL surface. If stereoscopic rendering is enabled, Dali will create
61 * two additional render tasks, on for each eye. Each render task will have its own camera parented
62 * to the default camera actor.
64 * The first RenderTask used for input handling will be the last one rendered, which also has input enabled,
65 * and has a valid source & camera actor; see SetInputEnabled().
67 * If none of the actors are hit in the last RenderTask rendered, then input handling will continue
68 * with the second last RenderTask rendered, and so on.
70 * All RenderTasks which target a frame-buffer (i.e. off screen) will be rendered before all RenderTasks
71 * which target the default GL surface. This allows the user to render intermediate targets which are used
72 * later when targeting the screen.
74 * A RenderTask targeting a frame-buffer can still be hit-tested, provided that the
75 * screen->frame-buffer coordinate conversion is successful; see SetScreenToFrameBufferFunction().
77 * If the refresh rate id REFRESH_ONCE and a "Finish" signal is connected, it will be emitted when the RenderTask is completed.
78 * Note that all connected signals must be disconnected before the object is destroyed. This is typically done in the
79 * object destructor, and requires either the Dali::Connection object or Dali::RenderTask handle to be stored.
82 * | %Signal Name | Method |
83 * |--------------|-----------------------|
84 * | finished | @ref FinishedSignal() |
87 class DALI_CORE_API RenderTask : public Handle
91 * @brief Enumeration for instances of properties belonging to the RenderTask class.
97 * @brief Enumeration for instances of properties belonging to the RenderTask class.
103 * @brief name "viewportPosition", type Vector2
106 VIEWPORT_POSITION = DEFAULT_OBJECT_PROPERTY_START_INDEX,
108 * @brief name "viewportSize", type Vector2
113 * @brief name "clearColor", type Vector4
118 * @brief name "requiresSync", type BOOLEAN
119 * @details By default, the sync object is not created.
120 * When native image source is used as render target, in order to track when the render to pixmap is completed, the GL sync should be enabled.
121 * Thus the RENDER_ONCE finished signal can be emit at the correct timing.
123 * @note The use of GL sync might cause deadlock with multiple access to the single pixmap happening in the same time.
130 * @brief Typedef for signals sent by this class.
133 using RenderTaskSignalType = Signal<void(RenderTask&)>;
136 * @brief A pointer to a function for converting screen to frame-buffer coordinates.
138 * @param[in,out] coordinates The screen coordinates to convert where (0,0) is the top-left of the screen
139 * @return True if the conversion was successful, otherwise coordinates should be unmodified
141 using ScreenToFrameBufferFunction = bool (*)(Vector2&);
144 * @brief A pointer to a function for converting screen to frame-buffer coordinates.
146 * @param[in,out] coordinates The screen coordinates to convert where (0,0) is the top-left of the screen
147 * @return True if the conversion was successful, otherwise coordinates should be unmodified
149 using ConstScreenToFrameBufferFunction = bool (*const)(Vector2&);
152 * @brief The default conversion function returns false for any screen coordinates.
154 * This effectively disables hit-testing for RenderTasks rendering to a frame buffer.
155 * See also FULLSCREEN_FRAMEBUFFER_FUNCTION below.
157 static ConstScreenToFrameBufferFunction DEFAULT_SCREEN_TO_FRAMEBUFFER_FUNCTION;
160 * @brief This conversion function outputs the (unmodified) screen coordinates as frame-buffer coordinates.
162 * Therefore the contents of an off-screen image is expected to be rendered "full screen".
164 static ConstScreenToFrameBufferFunction FULLSCREEN_FRAMEBUFFER_FUNCTION;
167 * @brief Enumeration for the refresh-rate of the RenderTask.
172 REFRESH_ONCE = 0, ///< Process once only e.g. take a snap-shot of the scene. @SINCE_1_0.0
173 REFRESH_ALWAYS = 1 ///< Process every frame. @SINCE_1_0.0
176 static const bool DEFAULT_EXCLUSIVE; ///< false
177 static const bool DEFAULT_INPUT_ENABLED; ///< true
178 static const Vector4 DEFAULT_CLEAR_COLOR; ///< Color::BLACK
179 static const bool DEFAULT_CLEAR_ENABLED; ///< false
180 static const bool DEFAULT_CULL_MODE; ///< true
181 static const uint32_t DEFAULT_REFRESH_RATE; ///< REFRESH_ALWAYS
184 * @brief Creates an empty RenderTask handle.
186 * This can be initialised with RenderTaskList::CreateRenderTask().
192 * @brief Downcasts a handle to RenderTask handle.
194 * If handle points to a RenderTask, the
195 * downcast produces valid handle. If not, the returned handle is left uninitialized.
197 * @param[in] handle A handle to an object
198 * @return A handle to a RenderTask or an uninitialized handle
200 static RenderTask DownCast(BaseHandle handle);
205 * This is non-virtual since derived Handle types must not contain data or virtual methods.
211 * @brief This copy constructor is required for (smart) pointer semantics.
214 * @param[in] handle A reference to the copied handle
216 RenderTask(const RenderTask& handle);
219 * @brief This assignment operator is required for (smart) pointer semantics.
222 * @param[in] rhs A reference to the copied handle
223 * @return A reference to this
225 RenderTask& operator=(const RenderTask& rhs);
228 * @brief Move constructor.
231 * @param[in] rhs A reference to the moved handle
233 RenderTask(RenderTask&& rhs) noexcept;
236 * @brief Move assignment operator.
239 * @param[in] rhs A reference to the moved handle
240 * @return A reference to this
242 RenderTask& operator=(RenderTask&& rhs) noexcept;
245 * @brief Sets the actors to be rendered.
247 * @param[in] actor This actor and its children will be rendered.
248 * If actor is an empty handle, then nothing will be rendered
250 void SetSourceActor(Actor actor);
253 * @brief Retrieves the actors to be rendered.
255 * @return This actor and its children will be rendered
257 Actor GetSourceActor() const;
260 * @brief Sets whether the RenderTask has exclusive access to the source actors; the default is false.
262 * @param[in] exclusive True if the source actors will only be rendered by this render-task
264 void SetExclusive(bool exclusive);
267 * @brief Queries whether the RenderTask has exclusive access to the source actors.
269 * @return True if the source actors will only be rendered by this render-task
271 bool IsExclusive() const;
274 * @brief Sets whether the render-task should be considered for input handling; the default is true.
276 * The task used for input handling will be last task in the RenderTaskList which has input enabled,
277 * and has a valid source & camera actor.
278 * A RenderTask targetting a frame-buffer can still be hit-tested, provided that the screen->frame-buffer
279 * coordinate conversion is successful; see also SetScreenToFrameBufferFunction().
281 * @param[in] enabled True if the render-task should be considered for input handling
283 void SetInputEnabled(bool enabled);
286 * @brief Queries whether the render-task should be considered for input handling.
288 * @return True if the render-task should be considered for input handling
290 bool GetInputEnabled() const;
293 * @brief Sets the actor from which the scene is viewed.
295 * @param[in] cameraActor The scene is viewed from the perspective of this actor
297 void SetCameraActor(CameraActor cameraActor);
300 * @brief Retrieves the actor from which the scene is viewed.
302 * @return The scene is viewed from the perspective of this actor
304 CameraActor GetCameraActor() const;
307 * @brief Sets the frame-buffer used as a render target.
309 * @param[in] frameBuffer A valid FrameBuffer handle to enable off-screen rendering, or an uninitialized handle to disable it
311 void SetFrameBuffer(FrameBuffer frameBuffer);
314 * @brief Retrieves the frame-buffer used as a render target.
316 * @return The framebuffer
318 FrameBuffer GetFrameBuffer() const;
321 * @brief Sets the function used to convert screen coordinates to frame-buffer coordinates.
323 * This is useful for hit-testing actors which are rendered off-screen.
325 * @param[in] conversionFunction The conversion function
327 void SetScreenToFrameBufferFunction(ScreenToFrameBufferFunction conversionFunction);
330 * @brief Retrieves the function used to convert screen coordinates to frame-buffer coordinates.
332 * @return The conversion function
334 ScreenToFrameBufferFunction GetScreenToFrameBufferFunction() const;
337 * @brief Sets the actor used to convert screen coordinates to frame-buffer coordinates.
339 * The local coordinates of the actor are mapped as frame-buffer coordinates.
340 * This is useful for hit-testing actors which are rendered off-screen.
342 * @param[in] mappingActor The actor used for conversion
343 * @note The mapping actor needs to be rendered by the default render task to make the mapping work properly.
345 void SetScreenToFrameBufferMappingActor(Actor mappingActor);
348 * @brief Retrieves the actor used to convert screen coordinates to frame-buffer coordinates.
350 * @return The actor used for conversion
352 Actor GetScreenToFrameBufferMappingActor() const;
355 * @brief Sets the actor to compute viewport of this render task.
356 * Actor should be added on Scene.
358 * @param[in] actor This actor is used to compute viewport of the render task.
359 * @note If window default camera is rotated and the actor is no longer a rectangle on the screen, Viewport may be computed incorrectly.
360 * The Viewport properties VIEWPORT_POSITION and VIEWPORT_SIZE is kept during using ViewportGuideActor, but only current value is changed.
362 void SetViewportGuideActor(Actor actor);
365 * @brief Retrieves the actor to compute viewport of this render task.
367 * @return This actor is used to compute viewport of the render task.
369 Actor GetViewportGuideActor() const;
372 * @brief Resets the actor to compute viewport of this render task.
374 * @note The Viewport properties VIEWPORT_POSITION and VIEWPORT_SIZE is still kept.
376 void ResetViewportGuideActor();
379 * @brief Sets the GL viewport position used when rendering.
381 * This specifies the transformation between normalized device coordinates and target window (or frame-buffer) coordinates.
382 * By default this will match the target window or frame-buffer size.
384 * @param[in] position The viewports position (x,y)
385 * @note Unlike the glViewport method, the x & y coordinates refer to the top-left of the viewport rectangle.
387 void SetViewportPosition(Vector2 position);
390 * @brief Retrieves the GL viewport position used when rendering.
392 * @return The viewport
394 Vector2 GetCurrentViewportPosition() const;
397 * @brief Sets the GL viewport size used when rendering.
399 * This specifies the transformation between normalized device coordinates and target window (or frame-buffer) coordinates.
400 * By default this will match the target window or frame-buffer size.
402 * @param[in] size The viewports size (width,height)
404 void SetViewportSize(Vector2 size);
407 * @brief Retrieves the GL viewport size used when rendering.
409 * @return The viewport
411 Vector2 GetCurrentViewportSize() const;
414 * @brief Sets the GL viewport used when rendering.
416 * This specifies the transformation between normalized device coordinates and target window (or frame-buffer) coordinates.
417 * By default this will match the target window or frame-buffer size.
419 * @param[in] viewport The new viewport
420 * @note Unlike the glViewport method, the x & y coordinates refer to the top-left of the viewport rectangle.
422 void SetViewport(Viewport viewport);
425 * @brief Retrieves the GL viewport used when rendering.
427 * @return The viewport
429 Viewport GetViewport() const;
432 * @brief Sets the clear color used when SetClearEnabled(true) is used.
434 * @param[in] color The new clear color
436 void SetClearColor(const Vector4& color);
439 * @brief Retrieves the clear color used when SetClearEnabled(true) is used.
441 * @return The clear color
442 * @note This property can be animated; the return value may not match the value written with SetClearColor().
444 Vector4 GetClearColor() const;
447 * @brief Sets whether the render-task will clear the results of previous render-tasks.
449 * The default is false.
452 * @param[in] enabled True if the render-task should clear
453 * @note The default GL surface is cleared automatically at the
454 * beginning of each frame; this setting is only useful when 2+
455 * render-tasks are used, and the result of the first task needs to
456 * be (partially) cleared before rendering the second.
459 void SetClearEnabled(bool enabled);
462 * @brief Queries whether the render-task will clear the results of previous render-tasks.
464 * @return True if the render-task should clear
466 bool GetClearEnabled() const;
469 * @brief Sets whether the render task will cull the actors to the camera's view frustum.
472 * @param[in] cullMode True if the renderers should be culled
473 * @note The default mode is to cull actors.
474 * @note If the shader uses @ref Shader::Hint::MODIFIES_GEOMETRY then culling optimizations are disabled.
477 void SetCullMode(bool cullMode);
480 * @brief Gets the cull mode.
483 * @return True if the render task should cull the actors to the camera's view frustum
485 bool GetCullMode() const;
488 * @brief Sets the refresh-rate of the RenderTask.
490 * The default is REFRESH_ALWAYS (1), meaning that the RenderTask
491 * will be processed every frame if the scene graph is changing. It
492 * may be desirable to process less frequently. For example,
493 * SetRefreshRate(3) will process once every 3 frames if the scene
494 * graph is changing. If the scene graph is not changing, then the
495 * render task will not be rendered, regardless of this value.
497 * The REFRESH_ONCE value means that the RenderTask will be
498 * processed once only, to take a snap-shot of the scene.
499 * Repeatedly calling SetRefreshRate(REFRESH_ONCE) will cause more
500 * snap-shots to be taken.
503 * @param[in] refreshRate The new refresh rate
505 void SetRefreshRate(uint32_t refreshRate);
508 * @brief Queries the refresh-rate of the RenderTask.
510 * @return The refresh-rate
512 uint32_t GetRefreshRate() const;
515 * @brief Gets viewport coordinates for given world position.
518 * @param[in] position The world position
519 * @param[out] viewportX The viewport x position
520 * @param[out] viewportY The viewport y position
521 * @return true if the position has a screen coordinate
523 bool WorldToViewport(const Vector3& position, float& viewportX, float& viewportY) const;
526 * @brief Gets actor local coordinates for given viewport coordinates.
529 * @param[in] actor The actor describing local coordinate system
530 * @param[in] viewportX The viewport x position
531 * @param[in] viewportY The viewport y position
532 * @param[out] localX The local x position
533 * @param[out] localY The local y position
534 * @return true if the screen position has a local coordinate
536 bool ViewportToLocal(Actor actor, float viewportX, float viewportY, float& localX, float& localY) const;
539 * Sets Render Pass key for this RenderTask.
540 * Shader code that matches this render pass is used for rendering.
541 * If no matching shader is found, the code with a render pass of 0 is used.
542 * In other cases, operation is not guaranteed.
543 * @param[in] renderPassTag RenderPassTag value for this render task.
544 * @note RenderPassTag of default RenderTask is 0u.
546 void SetRenderPassTag(uint32_t renderPassTag);
549 * Gets Render Pass key for this RenderTask.
550 * @return RenderPassTag value for this render task.
552 uint32_t GetRenderPassTag() const;
556 * @brief If the refresh rate is REFRESH_ONCE, connect to this signal to be notified when a RenderTask has finished.
558 * @return The signal to connect to
560 RenderTaskSignalType& FinishedSignal();
562 public: // Not intended for application developers
565 * @brief This constructor is used by Dali New() methods.
567 * @param[in] renderTask A pointer to a newly allocated render-task
569 explicit DALI_INTERNAL RenderTask(Internal::RenderTask* renderTask);
578 #endif //DALI_RENDER_TASK_H