2 * Copyright (c) 2020 Samsung Electronics Co., Ltd.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
19 #include "gaussian-blur-view-impl.h"
24 #include <dali/public-api/animation/constraint.h>
25 #include <dali/public-api/animation/constraints.h>
26 #include <dali/devel-api/common/stage.h>
27 #include <dali/public-api/object/type-registry.h>
28 #include <dali/public-api/object/type-registry-helper.h>
29 #include <dali/public-api/rendering/geometry.h>
30 #include <dali/public-api/rendering/renderer.h>
31 #include <dali/public-api/rendering/shader.h>
32 #include <dali/public-api/render-tasks/render-task-list.h>
33 #include <dali/integration-api/debug.h>
34 #include <dali/devel-api/actors/actor-devel.h>
37 #include <dali-toolkit/public-api/visuals/visual-properties.h>
38 #include <dali-toolkit/internal/controls/control/control-renderers.h>
41 // pixel format / size - set from JSON
42 // aspect ratio property needs to be able to be constrained also for cameras, not possible currently. Therefore changing aspect ratio of GaussianBlurView won't currently work
43 // default near clip value
44 // Manager object - re-use render targets if there are multiple GaussianBlurViews created
47 /////////////////////////////////////////////////////////
48 // IMPLEMENTATION NOTES
50 // As the GaussianBlurView actor changes size, the amount of pixels we need to blur changes. Therefore we need some way of doing this. However:-
51 // OnSetSize() does not get called when GaussianBlurView object size is modified using a Constraint.
52 // OnSizeAnimation() only gets called once per AnimateTo/By() and if an Animation has N such calls then only the final one will end up being used. Therefore we can't use
53 // OnSizeAnimation() to alter render target sizes.
54 // To get around the above problems, we use fixed sized render targets, from the last SetSize() call (which calls OnSetSize()), then we adjust the internal cameras / actors
55 // to take account of the changed GaussianBlurView object size, projecting to the unchanged render target sizes. This is done relative to the fixed render target / actor sizes
56 // by using constraints relative to the GaussianBlurView actor size.
60 // 1st mode, this control has a tree of actors (use Add() to add children) that are rendered and blurred.
61 // mRenderChildrenTask renders children to FB mRenderTargetForRenderingChildren
62 // mHorizBlurTask renders mHorizBlurActor Actor showing FB mRenderTargetForRenderingChildren into FB mRenderTarget2
63 // mVertBlurTask renders mVertBlurActor Actor showing FB mRenderTarget2 into FB mRenderTarget1
64 // mCompositeTask renders mCompositingActor Actor showing FB mRenderTarget1 into FB mRenderTargetForRenderingChildren
66 // 2nd mode, an image is blurred and rendered to a supplied target framebuffer
67 // mHorizBlurTask renders mHorizBlurActor Actor showing mUserInputImage into FB mRenderTarget2
68 // mVertBlurTask renders mVertBlurActor Actor showing mRenderTarget2 into FB mUserOutputRenderTarget
70 // Only this 2nd mode handles ActivateOnce
88 return Toolkit::GaussianBlurView::New();
91 DALI_TYPE_REGISTRATION_BEGIN( Toolkit::GaussianBlurView, Toolkit::Control, Create )
92 DALI_TYPE_REGISTRATION_END()
94 const unsigned int GAUSSIAN_BLUR_VIEW_DEFAULT_NUM_SAMPLES = 5;
95 const float GAUSSIAN_BLUR_VIEW_DEFAULT_BLUR_BELL_CURVE_WIDTH = 1.5f;
96 const Pixel::Format GAUSSIAN_BLUR_VIEW_DEFAULT_RENDER_TARGET_PIXEL_FORMAT = Pixel::RGBA8888;
97 const float GAUSSIAN_BLUR_VIEW_DEFAULT_BLUR_STRENGTH = 1.0f; // default, fully blurred
98 const char* const GAUSSIAN_BLUR_VIEW_STRENGTH_PROPERTY_NAME = "GaussianBlurStrengthPropertyName";
99 const float GAUSSIAN_BLUR_VIEW_DEFAULT_DOWNSAMPLE_WIDTH_SCALE = 0.5f;
100 const float GAUSSIAN_BLUR_VIEW_DEFAULT_DOWNSAMPLE_HEIGHT_SCALE = 0.5f;
102 const float ARBITRARY_FIELD_OF_VIEW = Math::PI / 4.0f;
104 const char* const GAUSSIAN_BLUR_FRAGMENT_SOURCE = DALI_COMPOSE_SHADER(
105 varying mediump vec2 vTexCoord;\n
106 uniform sampler2D sTexture;\n
107 uniform lowp vec4 uColor;\n
108 uniform mediump vec2 uSampleOffsets[NUM_SAMPLES];\n
109 uniform mediump float uSampleWeights[NUM_SAMPLES];\n
113 mediump vec4 col = texture2D(sTexture, vTexCoord + uSampleOffsets[0]) * uSampleWeights[0];\n
114 for (int i=1; i<NUM_SAMPLES; ++i)\n
116 col += texture2D(sTexture, vTexCoord + uSampleOffsets[i]) * uSampleWeights[i];\n
118 gl_FragColor = col;\n
125 GaussianBlurView::GaussianBlurView()
126 : Control( ControlBehaviour( DISABLE_SIZE_NEGOTIATION | DISABLE_STYLE_CHANGE_SIGNALS ) ),
127 mNumSamples(GAUSSIAN_BLUR_VIEW_DEFAULT_NUM_SAMPLES),
128 mBlurBellCurveWidth( 0.001f ),
129 mPixelFormat(GAUSSIAN_BLUR_VIEW_DEFAULT_RENDER_TARGET_PIXEL_FORMAT),
130 mDownsampleWidthScale(GAUSSIAN_BLUR_VIEW_DEFAULT_DOWNSAMPLE_WIDTH_SCALE),
131 mDownsampleHeightScale(GAUSSIAN_BLUR_VIEW_DEFAULT_DOWNSAMPLE_HEIGHT_SCALE),
132 mDownsampledWidth( 0.0f ),
133 mDownsampledHeight( 0.0f ),
134 mBlurUserImage( false ),
135 mRenderOnce( false ),
136 mBackgroundColor( Color::BLACK ),
137 mTargetSize(Vector2::ZERO),
138 mLastSize(Vector2::ZERO),
139 mChildrenRoot(Actor::New()),
140 mInternalRoot(Actor::New()),
141 mBlurStrengthPropertyIndex(Property::INVALID_INDEX),
144 SetBlurBellCurveWidth(GAUSSIAN_BLUR_VIEW_DEFAULT_BLUR_BELL_CURVE_WIDTH);
147 GaussianBlurView::GaussianBlurView( const unsigned int numSamples,
148 const float blurBellCurveWidth,
149 const Pixel::Format renderTargetPixelFormat,
150 const float downsampleWidthScale,
151 const float downsampleHeightScale,
153 : Control( ControlBehaviour( DISABLE_SIZE_NEGOTIATION | DISABLE_STYLE_CHANGE_SIGNALS ) ),
154 mNumSamples(numSamples),
155 mBlurBellCurveWidth( 0.001f ),
156 mPixelFormat(renderTargetPixelFormat),
157 mDownsampleWidthScale(downsampleWidthScale),
158 mDownsampleHeightScale(downsampleHeightScale),
159 mDownsampledWidth( 0.0f ),
160 mDownsampledHeight( 0.0f ),
161 mBlurUserImage( blurUserImage ),
162 mRenderOnce( false ),
163 mBackgroundColor( Color::BLACK ),
164 mTargetSize(Vector2::ZERO),
165 mLastSize(Vector2::ZERO),
166 mChildrenRoot(Actor::New()),
167 mInternalRoot(Actor::New()),
168 mBlurStrengthPropertyIndex(Property::INVALID_INDEX),
171 SetBlurBellCurveWidth(blurBellCurveWidth);
174 GaussianBlurView::~GaussianBlurView()
179 Toolkit::GaussianBlurView GaussianBlurView::New()
181 GaussianBlurView* impl = new GaussianBlurView();
183 Dali::Toolkit::GaussianBlurView handle = Dali::Toolkit::GaussianBlurView( *impl );
185 // Second-phase init of the implementation
186 // This can only be done after the CustomActor connection has been made...
192 Toolkit::GaussianBlurView GaussianBlurView::New(const unsigned int numSamples, const float blurBellCurveWidth, const Pixel::Format renderTargetPixelFormat,
193 const float downsampleWidthScale, const float downsampleHeightScale,
196 GaussianBlurView* impl = new GaussianBlurView( numSamples, blurBellCurveWidth, renderTargetPixelFormat,
197 downsampleWidthScale, downsampleHeightScale,
200 Dali::Toolkit::GaussianBlurView handle = Dali::Toolkit::GaussianBlurView( *impl );
202 // Second-phase init of the implementation
203 // This can only be done after the CustomActor connection has been made...
209 void GaussianBlurView::SetUserImageAndOutputRenderTarget(Texture inputImage, FrameBuffer outputRenderTarget)
211 // can only do this if the GaussianBlurView object was created with this parameter set
212 DALI_ASSERT_ALWAYS(mBlurUserImage);
214 mUserInputImage = inputImage;
216 SetRendererTexture( mHorizBlurActor.GetRendererAt(0), inputImage );
218 mUserOutputRenderTarget = outputRenderTarget;
221 FrameBuffer GaussianBlurView::GetBlurredRenderTarget() const
223 if(!mUserOutputRenderTarget)
225 return mRenderTargetForRenderingChildren;
228 return mUserOutputRenderTarget;
231 void GaussianBlurView::SetBackgroundColor( const Vector4& color )
233 mBackgroundColor = color;
236 Vector4 GaussianBlurView::GetBackgroundColor() const
238 return mBackgroundColor;
241 ///////////////////////////////////////////////////////////
246 void GaussianBlurView::OnInitialize()
248 // root actor to parent all user added actors, needed to allow us to set that subtree as exclusive for our child render task
249 mChildrenRoot.SetProperty( Actor::Property::PARENT_ORIGIN,ParentOrigin::CENTER );
250 mInternalRoot.SetProperty( Actor::Property::PARENT_ORIGIN,ParentOrigin::CENTER );
252 //////////////////////////////////////////////////////
255 std::ostringstream fragmentStringStream;
256 fragmentStringStream << "#define NUM_SAMPLES " << mNumSamples << "\n";
257 fragmentStringStream << GAUSSIAN_BLUR_FRAGMENT_SOURCE;
258 std::string fragmentSource(fragmentStringStream.str());
260 //////////////////////////////////////////////////////
263 // Create an actor for performing a horizontal blur on the texture
264 mHorizBlurActor = Actor::New();
265 mHorizBlurActor.SetProperty( Actor::Property::PARENT_ORIGIN,ParentOrigin::CENTER );
266 Renderer renderer = CreateRenderer( BASIC_VERTEX_SOURCE, fragmentSource.c_str() );
267 mHorizBlurActor.AddRenderer( renderer );
269 // Create an actor for performing a vertical blur on the texture
270 mVertBlurActor = Actor::New();
271 mVertBlurActor.SetProperty( Actor::Property::PARENT_ORIGIN,ParentOrigin::CENTER );
272 renderer = CreateRenderer( BASIC_VERTEX_SOURCE, fragmentSource.c_str() );
273 mVertBlurActor.AddRenderer( renderer );
275 // Register a property that the user can control to fade the blur in / out via the GaussianBlurView object
277 mBlurStrengthPropertyIndex = self.RegisterProperty(GAUSSIAN_BLUR_VIEW_STRENGTH_PROPERTY_NAME, GAUSSIAN_BLUR_VIEW_DEFAULT_BLUR_STRENGTH);
279 // Create an image view for compositing the blur and the original child actors render
282 mCompositingActor = Actor::New();
283 mCompositingActor.SetProperty( Actor::Property::PARENT_ORIGIN,ParentOrigin::CENTER );
284 mCompositingActor.SetProperty( Actor::Property::OPACITY,GAUSSIAN_BLUR_VIEW_DEFAULT_BLUR_STRENGTH); // ensure alpha is enabled for this object and set default value
285 renderer = CreateRenderer( BASIC_VERTEX_SOURCE, BASIC_FRAGMENT_SOURCE );
286 mCompositingActor.AddRenderer( renderer );
288 Constraint blurStrengthConstraint = Constraint::New<float>( mCompositingActor, Actor::Property::COLOR_ALPHA, EqualToConstraint());
289 blurStrengthConstraint.AddSource( Source( self, mBlurStrengthPropertyIndex) );
290 blurStrengthConstraint.Apply();
292 // Create an image view for holding final result, i.e. the blurred image. This will get rendered to screen later, via default / user render task
293 mTargetActor = Actor::New();
294 mTargetActor.SetProperty( Actor::Property::PARENT_ORIGIN,ParentOrigin::CENTER );
295 renderer = CreateRenderer( BASIC_VERTEX_SOURCE, BASIC_FRAGMENT_SOURCE );
296 mTargetActor.AddRenderer( renderer );
298 //////////////////////////////////////////////////////
299 // Create cameras for the renders corresponding to the view size
300 mRenderFullSizeCamera = CameraActor::New();
301 mRenderFullSizeCamera.SetInvertYAxis( true );
302 mRenderFullSizeCamera.SetProperty( Actor::Property::PARENT_ORIGIN,ParentOrigin::CENTER );
304 //////////////////////////////////////////////////////
305 // Connect to actor tree
306 mInternalRoot.Add( mCompositingActor );
307 mInternalRoot.Add( mTargetActor );
308 mInternalRoot.Add( mRenderFullSizeCamera );
311 //////////////////////////////////////////////////////
312 // Create camera for the renders corresponding to the (potentially downsampled) render targets' size
313 mRenderDownsampledCamera = CameraActor::New();
314 mRenderDownsampledCamera.SetInvertYAxis( true );
315 mRenderDownsampledCamera.SetProperty( Actor::Property::PARENT_ORIGIN,ParentOrigin::CENTER );
317 //////////////////////////////////////////////////////
318 // Connect to actor tree
319 Self().Add( mChildrenRoot );
320 mInternalRoot.Add( mHorizBlurActor );
321 mInternalRoot.Add( mVertBlurActor );
322 mInternalRoot.Add( mRenderDownsampledCamera );
326 void GaussianBlurView::OnSizeSet(const Vector3& targetSize)
328 mTargetSize = Vector2(targetSize);
330 mChildrenRoot.SetProperty( Actor::Property::SIZE, targetSize);
332 if( !mBlurUserImage )
334 mCompositingActor.SetProperty( Actor::Property::SIZE, targetSize);
335 mTargetActor.SetProperty( Actor::Property::SIZE, targetSize);
337 // Children render camera must move when GaussianBlurView object is resized. This is since we cannot change render target size - so we need to remap the child actors' rendering
338 // accordingly so they still exactly fill the render target. Note that this means the effective resolution of the child render changes as the GaussianBlurView object changes
339 // size, this is the trade off for not being able to modify render target size
340 // Change camera z position based on GaussianBlurView actor height
341 float cameraPosConstraintScale = 0.5f / tanf(ARBITRARY_FIELD_OF_VIEW * 0.5f);
342 mRenderFullSizeCamera.SetProperty( Actor::Property::POSITION_Z, mTargetSize.height * cameraPosConstraintScale);
346 // if we have already activated the blur, need to update render target sizes now to reflect the new size of this actor
353 Control::OnSizeSet( targetSize );
356 void GaussianBlurView::OnChildAdd( Actor& child )
358 if( child != mChildrenRoot && child != mInternalRoot)
360 mChildrenRoot.Add( child );
363 Control::OnChildAdd( child );
366 void GaussianBlurView::OnChildRemove( Actor& child )
368 mChildrenRoot.Remove( child );
370 Control::OnChildRemove( child );
373 void GaussianBlurView::AllocateResources()
375 mLastSize = mTargetSize;
377 // get size of downsampled render targets
378 mDownsampledWidth = mTargetSize.width * mDownsampleWidthScale;
379 mDownsampledHeight = mTargetSize.height * mDownsampleHeightScale;
381 // Create and place a camera for the renders corresponding to the (potentially downsampled) render targets' size
382 mRenderDownsampledCamera.SetFieldOfView(ARBITRARY_FIELD_OF_VIEW);
383 // TODO: how do we pick a reasonable value for near clip? Needs to relate to normal camera the user renders with, but we don't have a handle on it
384 mRenderDownsampledCamera.SetNearClippingPlane(1.0f);
385 mRenderDownsampledCamera.SetAspectRatio(mDownsampledWidth / mDownsampledHeight);
386 mRenderDownsampledCamera.SetType(Dali::Camera::FREE_LOOK); // camera orientation based solely on actor
388 mRenderDownsampledCamera.SetProperty( Actor::Property::POSITION, Vector3(0.0f, 0.0f, ((mDownsampledHeight * 0.5f) / tanf(ARBITRARY_FIELD_OF_VIEW * 0.5f))));
390 // setup for normal operation
393 // Create and place a camera for the children render, corresponding to its render target size
394 mRenderFullSizeCamera.SetFieldOfView(ARBITRARY_FIELD_OF_VIEW);
395 // TODO: how do we pick a reasonable value for near clip? Needs to relate to normal camera the user renders with, but we don't have a handle on it
396 mRenderFullSizeCamera.SetNearClippingPlane(1.0f);
397 mRenderFullSizeCamera.SetAspectRatio(mTargetSize.width / mTargetSize.height);
398 mRenderFullSizeCamera.SetType(Dali::Camera::FREE_LOOK); // camera orientation based solely on actor
400 float cameraPosConstraintScale = 0.5f / tanf(ARBITRARY_FIELD_OF_VIEW * 0.5f);
401 mRenderFullSizeCamera.SetProperty( Actor::Property::POSITION, Vector3(0.0f, 0.0f, mTargetSize.height * cameraPosConstraintScale));
403 // create offscreen buffer of new size to render our child actors to
404 mRenderTargetForRenderingChildren = FrameBuffer::New( mTargetSize.width, mTargetSize.height, FrameBuffer::Attachment::NONE );
405 Texture texture = Texture::New( TextureType::TEXTURE_2D, mPixelFormat, unsigned(mTargetSize.width), unsigned(mTargetSize.height) );
406 mRenderTargetForRenderingChildren.AttachColorTexture( texture );
408 // Set actor for performing a horizontal blur
409 SetRendererTexture( mHorizBlurActor.GetRendererAt(0), mRenderTargetForRenderingChildren );
411 // Create offscreen buffer for vert blur pass
412 mRenderTarget1 = FrameBuffer::New( mDownsampledWidth, mDownsampledHeight, FrameBuffer::Attachment::NONE );
413 texture = Texture::New(TextureType::TEXTURE_2D, mPixelFormat, unsigned(mDownsampledWidth), unsigned(mDownsampledHeight));
414 mRenderTarget1.AttachColorTexture( texture );
416 // use the completed blur in the first buffer and composite with the original child actors render
417 SetRendererTexture( mCompositingActor.GetRendererAt(0), mRenderTarget1 );
419 // set up target actor for rendering result, i.e. the blurred image
420 SetRendererTexture( mTargetActor.GetRendererAt(0), mRenderTargetForRenderingChildren );
423 // Create offscreen buffer for horiz blur pass
424 mRenderTarget2 = FrameBuffer::New( mDownsampledWidth, mDownsampledHeight, FrameBuffer::Attachment::NONE );
425 Texture texture = Texture::New(TextureType::TEXTURE_2D, mPixelFormat, unsigned(mDownsampledWidth), unsigned(mDownsampledHeight));
426 mRenderTarget2.AttachColorTexture( texture );
428 // size needs to match render target
429 mHorizBlurActor.SetProperty( Actor::Property::SIZE, Vector2(mDownsampledWidth, mDownsampledHeight) );
431 // size needs to match render target
432 mVertBlurActor.SetProperty( Actor::Property::SIZE, Vector2(mDownsampledWidth, mDownsampledHeight) );
433 SetRendererTexture( mVertBlurActor.GetRendererAt(0), mRenderTarget2 );
435 // set gaussian blur up for new sized render targets
436 SetShaderConstants();
439 void GaussianBlurView::CreateRenderTasks()
441 RenderTaskList taskList = Stage::GetCurrent().GetRenderTaskList();
445 // create render task to render our child actors to offscreen buffer
446 mRenderChildrenTask = taskList.CreateTask();
447 mRenderChildrenTask.SetSourceActor( mChildrenRoot );
448 mRenderChildrenTask.SetExclusive(true);
449 mRenderChildrenTask.SetInputEnabled( false );
450 mRenderChildrenTask.SetClearEnabled( true );
451 mRenderChildrenTask.SetClearColor( mBackgroundColor );
453 mRenderChildrenTask.SetCameraActor(mRenderFullSizeCamera);
454 mRenderChildrenTask.SetFrameBuffer( mRenderTargetForRenderingChildren );
458 mRenderChildrenTask.SetRefreshRate(RenderTask::REFRESH_ONCE);
462 // perform a horizontal blur targeting the second buffer
463 mHorizBlurTask = taskList.CreateTask();
464 mHorizBlurTask.SetSourceActor( mHorizBlurActor );
465 mHorizBlurTask.SetExclusive(true);
466 mHorizBlurTask.SetInputEnabled( false );
467 mHorizBlurTask.SetClearEnabled( true );
468 mHorizBlurTask.SetClearColor( mBackgroundColor );
469 mHorizBlurTask.SetCameraActor(mRenderDownsampledCamera);
470 mHorizBlurTask.SetFrameBuffer( mRenderTarget2 );
471 if( mRenderOnce || ( mRenderOnce && mBlurUserImage ) )
473 mHorizBlurTask.SetRefreshRate(RenderTask::REFRESH_ONCE);
476 // use the second buffer and perform a horizontal blur targeting the first buffer
477 mVertBlurTask = taskList.CreateTask();
478 mVertBlurTask.SetSourceActor( mVertBlurActor );
479 mVertBlurTask.SetExclusive(true);
480 mVertBlurTask.SetInputEnabled( false );
481 mVertBlurTask.SetClearEnabled( true );
482 mVertBlurTask.SetClearColor( mBackgroundColor );
483 mVertBlurTask.SetCameraActor(mRenderDownsampledCamera);
484 if(mUserOutputRenderTarget)
486 mVertBlurTask.SetFrameBuffer( mUserOutputRenderTarget );
490 mVertBlurTask.SetFrameBuffer( mRenderTarget1 );
492 if( mRenderOnce || ( mRenderOnce && mBlurUserImage ) )
494 mVertBlurTask.SetRefreshRate(RenderTask::REFRESH_ONCE);
495 mVertBlurTask.FinishedSignal().Connect( this, &GaussianBlurView::OnRenderTaskFinished );
498 // use the completed blur in the first buffer and composite with the original child actors render
501 mCompositeTask = taskList.CreateTask();
502 mCompositeTask.SetSourceActor( mCompositingActor );
503 mCompositeTask.SetExclusive(true);
504 mCompositeTask.SetInputEnabled( false );
506 mCompositeTask.SetCameraActor(mRenderFullSizeCamera);
507 mCompositeTask.SetFrameBuffer( mRenderTargetForRenderingChildren );
511 mCompositeTask.SetRefreshRate(RenderTask::REFRESH_ONCE);
516 void GaussianBlurView::RemoveRenderTasks()
518 RenderTaskList taskList = Stage::GetCurrent().GetRenderTaskList();
520 taskList.RemoveTask(mRenderChildrenTask);
521 taskList.RemoveTask(mHorizBlurTask);
522 taskList.RemoveTask(mVertBlurTask);
523 taskList.RemoveTask(mCompositeTask);
526 void GaussianBlurView::Activate()
530 // make sure resources are allocated and start the render tasks processing
531 Self().Add( mInternalRoot );
538 void GaussianBlurView::ActivateOnce()
545 void GaussianBlurView::Deactivate()
549 // stop render tasks processing
550 // Note: render target resources are automatically freed since we set the Image::Unused flag
551 mInternalRoot.Unparent();
552 mRenderTargetForRenderingChildren.Reset();
553 mRenderTarget1.Reset();
554 mRenderTarget2.Reset();
561 void GaussianBlurView::SetBlurBellCurveWidth(float blurBellCurveWidth)
563 // a value of zero leads to undefined Gaussian weights, do not allow user to do this
564 mBlurBellCurveWidth = std::max( blurBellCurveWidth, 0.001f );
567 float GaussianBlurView::CalcGaussianWeight(float x)
569 return (1.0f / sqrt(2.0f * Math::PI * mBlurBellCurveWidth)) * exp(-(x * x) / (2.0f * mBlurBellCurveWidth * mBlurBellCurveWidth));
572 void GaussianBlurView::SetShaderConstants()
577 float w, totalWeights;
580 uvOffsets = new Vector2[mNumSamples + 1];
581 weights = new float[mNumSamples + 1];
583 totalWeights = weights[0] = CalcGaussianWeight(0);
584 uvOffsets[0].x = 0.0f;
585 uvOffsets[0].y = 0.0f;
587 for(i=0; i<mNumSamples >> 1; i++)
589 w = CalcGaussianWeight((float)(i + 1));
590 weights[(i << 1) + 1] = w;
591 weights[(i << 1) + 2] = w;
592 totalWeights += w * 2.0f;
594 // offset texture lookup to between texels, that way the bilinear filter in the texture hardware will average two samples with one lookup
595 ofs = ((float)(i << 1)) + 1.5f;
597 // get offsets from units of pixels into uv coordinates in [0..1]
598 float ofsX = ofs / mDownsampledWidth;
599 float ofsY = ofs / mDownsampledHeight;
600 uvOffsets[(i << 1) + 1].x = ofsX;
601 uvOffsets[(i << 1) + 1].y = ofsY;
603 uvOffsets[(i << 1) + 2].x = -ofsX;
604 uvOffsets[(i << 1) + 2].y = -ofsY;
607 for(i=0; i<mNumSamples; i++)
609 weights[i] /= totalWeights;
612 // set shader constants
613 Vector2 xAxis(1.0f, 0.0f);
614 Vector2 yAxis(0.0f, 1.0f);
615 for (i = 0; i < mNumSamples; ++i )
617 mHorizBlurActor.RegisterProperty( GetSampleOffsetsPropertyName( i ), uvOffsets[ i ] * xAxis );
618 mHorizBlurActor.RegisterProperty( GetSampleWeightsPropertyName( i ), weights[ i ] );
620 mVertBlurActor.RegisterProperty( GetSampleOffsetsPropertyName( i ), uvOffsets[ i ] * yAxis );
621 mVertBlurActor.RegisterProperty( GetSampleWeightsPropertyName( i ), weights[ i ] );
628 std::string GaussianBlurView::GetSampleOffsetsPropertyName( unsigned int index ) const
630 DALI_ASSERT_ALWAYS( index < mNumSamples );
632 std::ostringstream oss;
633 oss << "uSampleOffsets[" << index << "]";
637 std::string GaussianBlurView::GetSampleWeightsPropertyName( unsigned int index ) const
639 DALI_ASSERT_ALWAYS( index < mNumSamples );
641 std::ostringstream oss;
642 oss << "uSampleWeights[" << index << "]";
646 Dali::Toolkit::GaussianBlurView::GaussianBlurViewSignal& GaussianBlurView::FinishedSignal()
648 return mFinishedSignal;
651 void GaussianBlurView::OnRenderTaskFinished(Dali::RenderTask& renderTask)
653 Toolkit::GaussianBlurView handle( GetOwner() );
654 mFinishedSignal.Emit( handle );
657 } // namespace Internal
658 } // namespace Toolkit