1 #ifndef __DALI_RENDER_TASK_H__
2 #define __DALI_RENDER_TASK_H__
5 * Copyright (c) 2014 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 <dali/public-api/math/viewport.h>
23 #include <dali/public-api/object/handle.h>
24 #include <dali/public-api/object/property-index-ranges.h>
25 #include <dali/public-api/signals/dali-signal.h>
32 class FrameBufferImage;
35 namespace Internal DALI_INTERNAL
41 * @brief RenderTasks describe how the Dali scene should be rendered.
43 * The Stage::GetRenderTaskList() method provides access to an ordered list of render-tasks.
45 * Each RenderTask must specify the source actors to be rendered, and a camera actor from
46 * which the scene is viewed.
48 * RenderTasks may optionally target a frame-buffer, otherwise the default GL surface is used;
49 * typically this is a window provided by the native system.
51 * By default Dali provides a single RenderTask, which renders the entire actor hierachy using
52 * a default camera actor and GL surface. If stereoscopic rendering is enabled, Dali will create
53 * two additional render tasks, on for each eye. Each render task will have its own camera parented
54 * to the default camera actor.
56 * The first RenderTask used for input handling will be the last one rendered, which also has input enabled,
57 * and has a valid source & camera actor; see SetInputEnabled().
59 * If none of the actors are hit in the last RenderTask rendered, then input handling will continue
60 * with the second last RenderTask rendered, and so on.
62 * All RenderTasks which target a frame-buffer (i.e. off screen) will be rendered before all RenderTasks
63 * which target the default GL surface. This allows the user to render intermediate targets which are used
64 * later when targetting the screen.
66 * A RenderTask targetting a frame-buffer can still be hit-tested, provided that the
67 * screen->frame-buffer coordinate conversion is successful; see SetScreenToFrameBufferFunction().
69 * If the refresh rate id REFRESH_ONCE and a "Finish" signal is connected, it will be emitted when the RenderTask is completed.
70 * Note that all connected signals must be disconnected before the object is destroyed. This is typically done in the
71 * object destructor, and requires either the Dali::Connection object or Dali::RenderTask handle to be stored.
74 * | %Signal Name | Method |
75 * |--------------|-----------------------|
76 * | finished | @ref FinishedSignal() |
78 class DALI_IMPORT_API RenderTask : public Handle
83 * @brief An enumeration of properties belonging to the RenderTask class.
89 VIEWPORT_POSITION = DEFAULT_OBJECT_PROPERTY_START_INDEX, ///< name "viewport-position", type Vector2
90 VIEWPORT_SIZE, ///< name "viewport-size", type Vector2
91 CLEAR_COLOR, ///< name "clear-color", type Vector4
96 * @brief Typedef for signals sent by this class.
98 typedef Signal< void (RenderTask& source) > RenderTaskSignalType;
101 * @brief A pointer to a function for converting screen to frame-buffer coordinates.
102 * @param[in,out] coordinates The screen coordinates to convert where (0,0) is the top-left of the screen.
103 * @return True if the conversion was successful, otherwise coordinates should be unmodified.
105 typedef bool (* ScreenToFrameBufferFunction)( Vector2& coordinates );
108 * @brief A pointer to a function for converting screen to frame-buffer coordinates.
109 * @param[in,out] coordinates The screen coordinates to convert where (0,0) is the top-left of the screen.
110 * @return True if the conversion was successful, otherwise coordinates should be unmodified.
112 typedef bool (* const ConstScreenToFrameBufferFunction)( Vector2& coordinates );
115 * @brief The default conversion function returns false for any screen coordinates.
117 * This effectively disables hit-testing for RenderTasks rendering to a frame buffer.
118 * See also FULLSCREEN_FRAMEBUFFER_FUNCTION below.
120 static ConstScreenToFrameBufferFunction DEFAULT_SCREEN_TO_FRAMEBUFFER_FUNCTION;
123 * @brief This conversion function outputs the (unmodified) screen coordinates as frame-buffer coordinates.
125 * Therefore the contents of an off-screen image is expected to be rendered "full screen".
127 static ConstScreenToFrameBufferFunction FULLSCREEN_FRAMEBUFFER_FUNCTION;
130 * @brief The refresh-rate of the RenderTask.
134 REFRESH_ONCE = 0, ///< Process once only e.g. take a snap-shot of the scene.
135 REFRESH_ALWAYS = 1 ///< Process every frame.
138 static const bool DEFAULT_EXCLUSIVE; ///< false
139 static const bool DEFAULT_INPUT_ENABLED; ///< true
140 static const Vector4 DEFAULT_CLEAR_COLOR; ///< Color::BLACK
141 static const bool DEFAULT_CLEAR_ENABLED; ///< false
142 static const bool DEFAULT_CULL_MODE; ///< true
143 static const unsigned int DEFAULT_REFRESH_RATE; ///< REFRESH_ALWAYS
146 * @brief Create an empty RenderTask handle.
148 * This can be initialised with RenderTaskList::CreateRenderTask().
153 * @brief Downcast a handle to RenderTask handle.
155 * If handle points to a RenderTask the
156 * downcast produces valid handle. If not the returned handle is left uninitialized.
157 * @param[in] handle A handle to an object.
158 * @return A handle to a RenderTask or an uninitialized handle.
160 static RenderTask DownCast( BaseHandle handle );
165 * This is non-virtual since derived Handle types must not contain data or virtual methods.
170 * @brief This copy constructor is required for (smart) pointer semantics.
172 * @param [in] handle A reference to the copied handle
174 RenderTask(const RenderTask& handle);
177 * @brief This assignment operator is required for (smart) pointer semantics.
179 * @param [in] rhs A reference to the copied handle
180 * @return A reference to this
182 RenderTask& operator=(const RenderTask& rhs);
185 * @brief Set the actors to be rendered.
186 * @param[in] actor This actor and its children will be rendered.
187 * If actor is an empty handle, then nothing will be rendered.
189 void SetSourceActor( Actor actor );
192 * @brief Retrieve the actors to be rendered.
193 * @return This actor and its children will be rendered.
195 Actor GetSourceActor() const;
198 * @brief Set whether the RenderTask has exclusive access to the source actors; the default is false.
199 * @param[in] exclusive True if the source actors will only be rendered by this render-task.
201 void SetExclusive( bool exclusive );
204 * @brief Query whether the RenderTask has exclusive access to the source actors.
205 * @return True if the source actors will only be rendered by this render-task.
207 bool IsExclusive() const;
210 * @brief Set whether the render-task should be considered for input handling; the default is true.
212 * The task used for input handling will be last task in the RenderTaskList which has input enabled,
213 * and has a valid source & camera actor.
214 * A RenderTask targetting a frame-buffer can still be hit-tested, provided that the screen->frame-buffer
215 * coordinate conversion is successful; see also SetScreenToFrameBufferFunction().
216 * @param[in] enabled True if the render-task should be considered for input handling.
218 void SetInputEnabled( bool enabled );
221 * @brief Query whether the render-task should be considered for input handling.
222 * @return True if the render-task should be considered for input handling.
224 bool GetInputEnabled() const;
227 * @brief Set the actor from which the scene is viewed.
228 * @param[in] cameraActor The scene is viewed from the perspective of this actor.
230 void SetCameraActor( CameraActor cameraActor );
233 * @brief Retrieve the actor from which the scene is viewed.
234 * @return The scene is viewed from the perspective of this actor.
236 CameraActor GetCameraActor() const;
239 * @brief Set the frame-buffer used as a render target.
240 * @param[in] frameBuffer A valid frame-buffer handle to enable off-screen rendering, or an uninitialized handle to disable.
242 void SetTargetFrameBuffer( FrameBufferImage frameBuffer );
245 * @brief Retrieve the frame-buffer used as a render target.
246 * @return A valid frame-buffer handle, or an uninitialised handle if off-screen rendering is disabled.
248 FrameBufferImage GetTargetFrameBuffer() const;
251 * @brief Set the function used to convert screen coordinates to frame-buffer coordinates.
253 * This is useful for hit-testing actors which are rendered off-screen.
254 * @param[in] conversionFunction The conversion function.
256 void SetScreenToFrameBufferFunction( ScreenToFrameBufferFunction conversionFunction );
259 * @brief Retrieve the function used to convert screen coordinates to frame-buffer coordinates.
260 * @return The conversion function.
262 ScreenToFrameBufferFunction GetScreenToFrameBufferFunction() const;
265 * @brief Set the actor used to convert screen coordinates to frame-buffer coordinates.
267 * The local coordinates of the actor are mapped as frame-buffer coordinates.
268 * This is useful for hit-testing actors which are rendered off-screen.
269 * Note: The mapping actor needs to be rendered by the default render task to make the mapping work properly.
270 * @param[in] mappingActor The actor used for conversion.
272 void SetScreenToFrameBufferMappingActor( Actor mappingActor );
275 * @brief Retrieve the actor used to convert screen coordinates to frame-buffer coordinates.
276 * @return The actor used for conversion.
278 Actor GetScreenToFrameBufferMappingActor() const;
281 * @brief Set the GL viewport position used when rendering.
283 * This specifies the transformation between normalized device coordinates and target window (or frame-buffer) coordinates.
284 * By default this will match the target window or frame-buffer size.
285 * @note Unlike the glViewport method, the x & y coordinates refer to the top-left of the viewport rectangle.
286 * @param[in] position The viewports position (x,y)
288 void SetViewportPosition( Vector2 position );
291 * @brief Retrieve the GL viewport position used when rendering.
292 * @return The viewport.
294 Vector2 GetCurrentViewportPosition() const;
297 * @brief Set the GL viewport size used when rendering.
299 * This specifies the transformation between normalized device coordinates and target window (or frame-buffer) coordinates.
300 * By default this will match the target window or frame-buffer size.
301 * @param[in] size The viewports size (width,height)
303 void SetViewportSize( Vector2 size );
306 * @brief Retrieve the GL viewport size used when rendering.
307 * @return The viewport.
309 Vector2 GetCurrentViewportSize() const;
312 * @brief Set the GL viewport used when rendering.
314 * This specifies the transformation between normalized device coordinates and target window (or frame-buffer) coordinates.
315 * By default this will match the target window or frame-buffer size.
316 * @note Unlike the glViewport method, the x & y coordinates refer to the top-left of the viewport rectangle.
317 * @param[in] viewport The new viewport.
319 void SetViewport( Viewport viewport );
322 * @brief Retrieve the GL viewport used when rendering.
323 * @return The viewport.
325 Viewport GetViewport() const;
328 * @brief Set the clear color used when SetClearEnabled(true) is used.
329 * @param[in] color The new clear color.
331 void SetClearColor( const Vector4& color );
334 * @brief Retrieve the clear color used when SetClearEnabled(true) is used.
335 * @note This property can be animated; the return value may not match the value written with SetClearColor().
336 * @return The clear color.
338 Vector4 GetClearColor() const;
341 * @brief Set whether the render-task will clear the results of previous render-tasks.
343 * The default is false.
345 * @note The default GL surface is cleared automatically at the
346 * beginning of each frame; this setting is only useful when 2+
347 * render-tasks are used, and the result of the first task needs to
348 * be (partially) cleared before rendering the second.
350 * @param[in] enabled True if the render-task should clear.
352 void SetClearEnabled( bool enabled );
355 * @brief Query whether the render-task will clear the results of previous render-tasks.
356 * @return True if the render-task should clear.
358 bool GetClearEnabled() const;
361 * @brief Set whether the render task will cull the actors to the camera's view frustum.
363 * Note that this will only affect image actors that use the default vertex shader.
364 * The default mode is to cull actors.
365 * @param[in] cullMode True if the renderers should be culled.
367 void SetCullMode( bool cullMode );
370 * @brief Get the cull mode.
372 * @return True if the render task should cull the actors to the camera's view frustum
374 bool GetCullMode() const;
377 * @brief Set the refresh-rate of the RenderTask.
379 * The default is REFRESH_ALWAYS (1), meaning that the RenderTask
380 * will be processed every frame if the scene graph is changing. It
381 * may be desirable to process less frequently. For example,
382 * SetRefreshRate(3) will process once every 3 frames if the scene
383 * graph is changing. If the scene graph is not changing, then the
384 * render task will not be rendered, regardless of this value.
386 * The REFRESH_ONCE value means that the RenderTask will be
387 * processed once only, to take a snap-shot of the scene.
388 * Repeatedly calling SetRefreshRate(REFRESH_ONCE) will cause more
389 * snap-shots to be taken.
391 * @param[in] refreshRate The new refresh rate.
393 void SetRefreshRate( unsigned int refreshRate );
396 * @brief Query the refresh-rate of the RenderTask.
397 * @return The refresh-rate.
399 unsigned int GetRefreshRate() const;
404 * @brief If the refresh rate is REFRESH_ONCE, connect to this signal to be notified when a RenderTask has finished.
406 RenderTaskSignalType& FinishedSignal();
408 public: // Not intended for application developers
411 * @brief This constructor is used by Dali New() methods.
412 * @param [in] renderTask A pointer to a newly allocated render-task
414 explicit DALI_INTERNAL RenderTask( Internal::RenderTask* renderTask );
419 #endif //__DALI_RENDER_TASK_H__