2 * Copyright (c) 2017 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/public-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/property-buffer.h>
31 #include <dali/public-api/rendering/renderer.h>
32 #include <dali/public-api/rendering/shader.h>
33 #include <dali/public-api/render-tasks/render-task-list.h>
34 #include <dali/integration-api/debug.h>
37 #include <dali-toolkit/public-api/visuals/visual-properties.h>
38 #include <dali-toolkit/internal/controls/control/control-renderers.h>
39 #include <dali-toolkit/internal/controls/control/control-data-impl.h>
42 // pixel format / size - set from JSON
43 // 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
44 // default near clip value
45 // Manager object - re-use render targets if there are multiple GaussianBlurViews created
48 /////////////////////////////////////////////////////////
49 // IMPLEMENTATION NOTES
51 // As the GaussianBlurView actor changes size, the amount of pixels we need to blur changes. Therefore we need some way of doing this. However:-
52 // OnSetSize() does not get called when GaussianBlurView object size is modified using a Constraint.
53 // 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
54 // OnSizeAnimation() to alter render target sizes.
55 // 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
56 // 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
57 // by using constraints relative to the GaussianBlurView actor size.
61 // 1st mode, this control has a tree of actors (use Add() to add children) that are rendered and blurred.
62 // mRenderChildrenTask renders children to FB mRenderTargetForRenderingChildren
63 // mHorizBlurTask renders mHorizBlurActor Actor showing FB mRenderTargetForRenderingChildren into FB mRenderTarget2
64 // mVertBlurTask renders mVertBlurActor Actor showing FB mRenderTarget2 into FB mRenderTarget1
65 // mCompositeTask renders mCompositingActor Actor showing FB mRenderTarget1 into FB mRenderTargetForRenderingChildren
67 // 2nd mode, an image is blurred and rendered to a supplied target framebuffer
68 // mHorizBlurTask renders mHorizBlurActor Actor showing mUserInputImage into FB mRenderTarget2
69 // mVertBlurTask renders mVertBlurActor Actor showing mRenderTarget2 into FB mUserOutputRenderTarget
71 // Only this 2nd mode handles ActivateOnce
89 return Toolkit::GaussianBlurView::New();
92 DALI_TYPE_REGISTRATION_BEGIN( Toolkit::GaussianBlurView, Toolkit::Control, Create )
93 DALI_TYPE_REGISTRATION_END()
95 const unsigned int GAUSSIAN_BLUR_VIEW_DEFAULT_NUM_SAMPLES = 5;
96 const float GAUSSIAN_BLUR_VIEW_DEFAULT_BLUR_BELL_CURVE_WIDTH = 1.5f;
97 const Pixel::Format GAUSSIAN_BLUR_VIEW_DEFAULT_RENDER_TARGET_PIXEL_FORMAT = Pixel::RGBA8888;
98 const float GAUSSIAN_BLUR_VIEW_DEFAULT_BLUR_STRENGTH = 1.0f; // default, fully blurred
99 const char* const GAUSSIAN_BLUR_VIEW_STRENGTH_PROPERTY_NAME = "GaussianBlurStrengthPropertyName";
100 const float GAUSSIAN_BLUR_VIEW_DEFAULT_DOWNSAMPLE_WIDTH_SCALE = 0.5f;
101 const float GAUSSIAN_BLUR_VIEW_DEFAULT_DOWNSAMPLE_HEIGHT_SCALE = 0.5f;
103 const float ARBITRARY_FIELD_OF_VIEW = Math::PI / 4.0f;
105 const char* const GAUSSIAN_BLUR_FRAGMENT_SOURCE = DALI_COMPOSE_SHADER(
106 varying mediump vec2 vTexCoord;\n
107 uniform sampler2D sTexture;\n
108 uniform lowp vec4 uColor;\n
109 uniform mediump vec2 uSampleOffsets[NUM_SAMPLES];\n
110 uniform mediump float uSampleWeights[NUM_SAMPLES];\n
114 mediump vec4 col = texture2D(sTexture, vTexCoord + uSampleOffsets[0]) * uSampleWeights[0];\n
115 for (int i=1; i<NUM_SAMPLES; ++i)\n
117 col += texture2D(sTexture, vTexCoord + uSampleOffsets[i]) * uSampleWeights[i];\n
119 gl_FragColor = col;\n
126 GaussianBlurView::GaussianBlurView()
127 : Control( ControlBehaviour( DISABLE_SIZE_NEGOTIATION | DISABLE_STYLE_CHANGE_SIGNALS ) ),
128 mNumSamples(GAUSSIAN_BLUR_VIEW_DEFAULT_NUM_SAMPLES),
129 mBlurBellCurveWidth( 0.001f ),
130 mPixelFormat(GAUSSIAN_BLUR_VIEW_DEFAULT_RENDER_TARGET_PIXEL_FORMAT),
131 mDownsampleWidthScale(GAUSSIAN_BLUR_VIEW_DEFAULT_DOWNSAMPLE_WIDTH_SCALE),
132 mDownsampleHeightScale(GAUSSIAN_BLUR_VIEW_DEFAULT_DOWNSAMPLE_HEIGHT_SCALE),
133 mDownsampledWidth( 0.0f ),
134 mDownsampledHeight( 0.0f ),
135 mBlurUserImage( false ),
136 mRenderOnce( false ),
137 mBackgroundColor( Color::BLACK ),
138 mTargetSize(Vector2::ZERO),
139 mLastSize(Vector2::ZERO),
140 mChildrenRoot(Actor::New()),
141 mInternalRoot(Actor::New()),
142 mBlurStrengthPropertyIndex(Property::INVALID_INDEX),
145 SetBlurBellCurveWidth(GAUSSIAN_BLUR_VIEW_DEFAULT_BLUR_BELL_CURVE_WIDTH);
146 DevelControl::SetAccessibilityConstructor( Self(), []( Dali::Actor actor ) {
147 return std::unique_ptr< Dali::Accessibility::Accessible >(
148 new Control::Impl::AccessibleImpl( actor, Dali::Accessibility::Role::FILLER ) );
152 GaussianBlurView::GaussianBlurView( const unsigned int numSamples,
153 const float blurBellCurveWidth,
154 const Pixel::Format renderTargetPixelFormat,
155 const float downsampleWidthScale,
156 const float downsampleHeightScale,
158 : Control( ControlBehaviour( DISABLE_SIZE_NEGOTIATION | DISABLE_STYLE_CHANGE_SIGNALS ) ),
159 mNumSamples(numSamples),
160 mBlurBellCurveWidth( 0.001f ),
161 mPixelFormat(renderTargetPixelFormat),
162 mDownsampleWidthScale(downsampleWidthScale),
163 mDownsampleHeightScale(downsampleHeightScale),
164 mDownsampledWidth( 0.0f ),
165 mDownsampledHeight( 0.0f ),
166 mBlurUserImage( blurUserImage ),
167 mRenderOnce( false ),
168 mBackgroundColor( Color::BLACK ),
169 mTargetSize(Vector2::ZERO),
170 mLastSize(Vector2::ZERO),
171 mChildrenRoot(Actor::New()),
172 mInternalRoot(Actor::New()),
173 mBlurStrengthPropertyIndex(Property::INVALID_INDEX),
176 SetBlurBellCurveWidth(blurBellCurveWidth);
179 GaussianBlurView::~GaussianBlurView()
184 Toolkit::GaussianBlurView GaussianBlurView::New()
186 GaussianBlurView* impl = new GaussianBlurView();
188 Dali::Toolkit::GaussianBlurView handle = Dali::Toolkit::GaussianBlurView( *impl );
190 // Second-phase init of the implementation
191 // This can only be done after the CustomActor connection has been made...
197 Toolkit::GaussianBlurView GaussianBlurView::New(const unsigned int numSamples, const float blurBellCurveWidth, const Pixel::Format renderTargetPixelFormat,
198 const float downsampleWidthScale, const float downsampleHeightScale,
201 GaussianBlurView* impl = new GaussianBlurView( numSamples, blurBellCurveWidth, renderTargetPixelFormat,
202 downsampleWidthScale, downsampleHeightScale,
205 Dali::Toolkit::GaussianBlurView handle = Dali::Toolkit::GaussianBlurView( *impl );
207 // Second-phase init of the implementation
208 // This can only be done after the CustomActor connection has been made...
214 /////////////////////////////////////////////////////////////
215 // for creating a subtree for all user added child actors, so that we can have them exclusive to the mRenderChildrenTask and our other actors exclusive to our other tasks
216 // DEPRECATED: overloading Actor::Add()/Remove() not nice since breaks polymorphism. Need another method to pass ownership of added child actors to our internal actor root.
217 void GaussianBlurView::Add(Actor child)
219 mChildrenRoot.Add(child);
222 void GaussianBlurView::Remove(Actor child)
224 mChildrenRoot.Remove(child);
227 void GaussianBlurView::SetUserImageAndOutputRenderTarget(Texture inputImage, FrameBuffer outputRenderTarget)
229 // can only do this if the GaussianBlurView object was created with this parameter set
230 DALI_ASSERT_ALWAYS(mBlurUserImage);
232 mUserInputImage = inputImage;
234 SetRendererTexture( mHorizBlurActor.GetRendererAt(0), inputImage );
236 mUserOutputRenderTarget = outputRenderTarget;
239 FrameBuffer GaussianBlurView::GetBlurredRenderTarget() const
241 if(!mUserOutputRenderTarget)
243 return mRenderTargetForRenderingChildren;
246 return mUserOutputRenderTarget;
249 void GaussianBlurView::SetBackgroundColor( const Vector4& color )
251 mBackgroundColor = color;
254 Vector4 GaussianBlurView::GetBackgroundColor() const
256 return mBackgroundColor;
259 ///////////////////////////////////////////////////////////
264 void GaussianBlurView::OnInitialize()
266 // root actor to parent all user added actors, needed to allow us to set that subtree as exclusive for our child render task
267 mChildrenRoot.SetParentOrigin(ParentOrigin::CENTER);
268 mInternalRoot.SetParentOrigin(ParentOrigin::CENTER);
270 //////////////////////////////////////////////////////
273 std::ostringstream fragmentStringStream;
274 fragmentStringStream << "#define NUM_SAMPLES " << mNumSamples << "\n";
275 fragmentStringStream << GAUSSIAN_BLUR_FRAGMENT_SOURCE;
276 std::string fragmentSource(fragmentStringStream.str());
278 //////////////////////////////////////////////////////
281 // Create an actor for performing a horizontal blur on the texture
282 mHorizBlurActor = Actor::New();
283 mHorizBlurActor.SetParentOrigin(ParentOrigin::CENTER);
284 Renderer renderer = CreateRenderer( BASIC_VERTEX_SOURCE, fragmentSource.c_str() );
285 mHorizBlurActor.AddRenderer( renderer );
287 // Create an actor for performing a vertical blur on the texture
288 mVertBlurActor = Actor::New();
289 mVertBlurActor.SetParentOrigin(ParentOrigin::CENTER);
290 renderer = CreateRenderer( BASIC_VERTEX_SOURCE, fragmentSource.c_str() );
291 mVertBlurActor.AddRenderer( renderer );
293 // Register a property that the user can control to fade the blur in / out via the GaussianBlurView object
295 mBlurStrengthPropertyIndex = self.RegisterProperty(GAUSSIAN_BLUR_VIEW_STRENGTH_PROPERTY_NAME, GAUSSIAN_BLUR_VIEW_DEFAULT_BLUR_STRENGTH);
297 // Create an image view for compositing the blur and the original child actors render
300 mCompositingActor = Actor::New();
301 mCompositingActor.SetParentOrigin(ParentOrigin::CENTER);
302 mCompositingActor.SetOpacity(GAUSSIAN_BLUR_VIEW_DEFAULT_BLUR_STRENGTH); // ensure alpha is enabled for this object and set default value
303 renderer = CreateRenderer( BASIC_VERTEX_SOURCE, BASIC_FRAGMENT_SOURCE );
304 mCompositingActor.AddRenderer( renderer );
306 Constraint blurStrengthConstraint = Constraint::New<float>( mCompositingActor, Actor::Property::COLOR_ALPHA, EqualToConstraint());
307 blurStrengthConstraint.AddSource( Source( self, mBlurStrengthPropertyIndex) );
308 blurStrengthConstraint.Apply();
310 // 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
311 mTargetActor = Actor::New();
312 mTargetActor.SetParentOrigin(ParentOrigin::CENTER);
313 renderer = CreateRenderer( BASIC_VERTEX_SOURCE, BASIC_FRAGMENT_SOURCE );
314 mTargetActor.AddRenderer( renderer );
316 //////////////////////////////////////////////////////
317 // Create cameras for the renders corresponding to the view size
318 mRenderFullSizeCamera = CameraActor::New();
319 mRenderFullSizeCamera.SetInvertYAxis( true );
320 mRenderFullSizeCamera.SetParentOrigin(ParentOrigin::CENTER);
322 //////////////////////////////////////////////////////
323 // Connect to actor tree
324 mInternalRoot.Add( mCompositingActor );
325 mInternalRoot.Add( mTargetActor );
326 mInternalRoot.Add( mRenderFullSizeCamera );
329 //////////////////////////////////////////////////////
330 // Create camera for the renders corresponding to the (potentially downsampled) render targets' size
331 mRenderDownsampledCamera = CameraActor::New();
332 mRenderDownsampledCamera.SetInvertYAxis( true );
333 mRenderDownsampledCamera.SetParentOrigin(ParentOrigin::CENTER);
335 //////////////////////////////////////////////////////
336 // Connect to actor tree
337 Self().Add( mChildrenRoot );
338 Self().Add( mInternalRoot );
339 mInternalRoot.Add( mHorizBlurActor );
340 mInternalRoot.Add( mVertBlurActor );
341 mInternalRoot.Add( mRenderDownsampledCamera );
345 void GaussianBlurView::OnSizeSet(const Vector3& targetSize)
347 mTargetSize = Vector2(targetSize);
349 mChildrenRoot.SetSize(targetSize);
351 if( !mBlurUserImage )
353 mCompositingActor.SetSize(targetSize);
354 mTargetActor.SetSize(targetSize);
356 // 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
357 // 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
358 // size, this is the trade off for not being able to modify render target size
359 // Change camera z position based on GaussianBlurView actor height
360 float cameraPosConstraintScale = 0.5f / tanf(ARBITRARY_FIELD_OF_VIEW * 0.5f);
361 mRenderFullSizeCamera.SetZ(mTargetSize.height * cameraPosConstraintScale);
365 // if we have already activated the blur, need to update render target sizes now to reflect the new size of this actor
372 Control::OnSizeSet( targetSize );
375 void GaussianBlurView::OnChildAdd( Actor& child )
377 if( child != mChildrenRoot && child != mInternalRoot)
379 mChildrenRoot.Add( child );
382 Control::OnChildAdd( child );
385 void GaussianBlurView::OnChildRemove( Actor& child )
387 mChildrenRoot.Remove( child );
389 Control::OnChildRemove( child );
392 void GaussianBlurView::AllocateResources()
394 // size of render targets etc is based on the size of this actor, ignoring z
395 if(mTargetSize != mLastSize)
397 mLastSize = mTargetSize;
399 // get size of downsampled render targets
400 mDownsampledWidth = mTargetSize.width * mDownsampleWidthScale;
401 mDownsampledHeight = mTargetSize.height * mDownsampleHeightScale;
403 // Create and place a camera for the renders corresponding to the (potentially downsampled) render targets' size
404 mRenderDownsampledCamera.SetFieldOfView(ARBITRARY_FIELD_OF_VIEW);
405 // 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
406 mRenderDownsampledCamera.SetNearClippingPlane(1.0f);
407 mRenderDownsampledCamera.SetAspectRatio(mDownsampledWidth / mDownsampledHeight);
408 mRenderDownsampledCamera.SetType(Dali::Camera::FREE_LOOK); // camera orientation based solely on actor
410 mRenderDownsampledCamera.SetPosition(0.0f, 0.0f, ((mDownsampledHeight * 0.5f) / tanf(ARBITRARY_FIELD_OF_VIEW * 0.5f)));
412 // setup for normal operation
415 // Create and place a camera for the children render, corresponding to its render target size
416 mRenderFullSizeCamera.SetFieldOfView(ARBITRARY_FIELD_OF_VIEW);
417 // 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
418 mRenderFullSizeCamera.SetNearClippingPlane(1.0f);
419 mRenderFullSizeCamera.SetAspectRatio(mTargetSize.width / mTargetSize.height);
420 mRenderFullSizeCamera.SetType(Dali::Camera::FREE_LOOK); // camera orientation based solely on actor
422 float cameraPosConstraintScale = 0.5f / tanf(ARBITRARY_FIELD_OF_VIEW * 0.5f);
423 mRenderFullSizeCamera.SetPosition(0.0f, 0.0f, mTargetSize.height * cameraPosConstraintScale);
425 // create offscreen buffer of new size to render our child actors to
426 mRenderTargetForRenderingChildren = FrameBuffer::New( mTargetSize.width, mTargetSize.height, FrameBuffer::Attachment::NONE );
427 Texture texture = Texture::New( TextureType::TEXTURE_2D, mPixelFormat, unsigned(mTargetSize.width), unsigned(mTargetSize.height) );
428 mRenderTargetForRenderingChildren.AttachColorTexture( texture );
430 // Set actor for performing a horizontal blur
431 SetRendererTexture( mHorizBlurActor.GetRendererAt(0), mRenderTargetForRenderingChildren );
433 // Create offscreen buffer for vert blur pass
434 mRenderTarget1 = FrameBuffer::New( mDownsampledWidth, mDownsampledHeight, FrameBuffer::Attachment::NONE );
435 texture = Texture::New(TextureType::TEXTURE_2D, mPixelFormat, unsigned(mDownsampledWidth), unsigned(mDownsampledHeight));
436 mRenderTarget1.AttachColorTexture( texture );
438 // use the completed blur in the first buffer and composite with the original child actors render
439 SetRendererTexture( mCompositingActor.GetRendererAt(0), mRenderTarget1 );
441 // set up target actor for rendering result, i.e. the blurred image
442 SetRendererTexture( mTargetActor.GetRendererAt(0), mRenderTargetForRenderingChildren );
445 // Create offscreen buffer for horiz blur pass
446 mRenderTarget2 = FrameBuffer::New( mDownsampledWidth, mDownsampledHeight, FrameBuffer::Attachment::NONE );
447 Texture texture = Texture::New(TextureType::TEXTURE_2D, mPixelFormat, unsigned(mDownsampledWidth), unsigned(mDownsampledHeight));
448 mRenderTarget2.AttachColorTexture( texture );
450 // size needs to match render target
451 mHorizBlurActor.SetSize(mDownsampledWidth, mDownsampledHeight);
453 // size needs to match render target
454 mVertBlurActor.SetSize(mDownsampledWidth, mDownsampledHeight);
455 SetRendererTexture( mVertBlurActor.GetRendererAt(0), mRenderTarget2 );
457 // set gaussian blur up for new sized render targets
458 SetShaderConstants();
462 void GaussianBlurView::CreateRenderTasks()
464 RenderTaskList taskList = Stage::GetCurrent().GetRenderTaskList();
468 // create render task to render our child actors to offscreen buffer
469 mRenderChildrenTask = taskList.CreateTask();
470 mRenderChildrenTask.SetSourceActor( mChildrenRoot );
471 mRenderChildrenTask.SetExclusive(true);
472 mRenderChildrenTask.SetInputEnabled( false );
473 mRenderChildrenTask.SetClearEnabled( true );
474 mRenderChildrenTask.SetClearColor( mBackgroundColor );
476 mRenderChildrenTask.SetCameraActor(mRenderFullSizeCamera);
477 mRenderChildrenTask.SetFrameBuffer( mRenderTargetForRenderingChildren );
480 // perform a horizontal blur targeting the second buffer
481 mHorizBlurTask = taskList.CreateTask();
482 mHorizBlurTask.SetSourceActor( mHorizBlurActor );
483 mHorizBlurTask.SetExclusive(true);
484 mHorizBlurTask.SetInputEnabled( false );
485 mHorizBlurTask.SetClearEnabled( true );
486 mHorizBlurTask.SetClearColor( mBackgroundColor );
487 mHorizBlurTask.SetCameraActor(mRenderDownsampledCamera);
488 mHorizBlurTask.SetFrameBuffer( mRenderTarget2 );
489 if( mRenderOnce && mBlurUserImage )
491 mHorizBlurTask.SetRefreshRate(RenderTask::REFRESH_ONCE);
494 // use the second buffer and perform a horizontal blur targeting the first buffer
495 mVertBlurTask = taskList.CreateTask();
496 mVertBlurTask.SetSourceActor( mVertBlurActor );
497 mVertBlurTask.SetExclusive(true);
498 mVertBlurTask.SetInputEnabled( false );
499 mVertBlurTask.SetClearEnabled( true );
500 mVertBlurTask.SetClearColor( mBackgroundColor );
501 mVertBlurTask.SetCameraActor(mRenderDownsampledCamera);
502 if(mUserOutputRenderTarget)
504 mVertBlurTask.SetFrameBuffer( mUserOutputRenderTarget );
508 mVertBlurTask.SetFrameBuffer( mRenderTarget1 );
510 if( mRenderOnce && mBlurUserImage )
512 mVertBlurTask.SetRefreshRate(RenderTask::REFRESH_ONCE);
513 mVertBlurTask.FinishedSignal().Connect( this, &GaussianBlurView::OnRenderTaskFinished );
516 // use the completed blur in the first buffer and composite with the original child actors render
519 mCompositeTask = taskList.CreateTask();
520 mCompositeTask.SetSourceActor( mCompositingActor );
521 mCompositeTask.SetExclusive(true);
522 mCompositeTask.SetInputEnabled( false );
524 mCompositeTask.SetCameraActor(mRenderFullSizeCamera);
525 mCompositeTask.SetFrameBuffer( mRenderTargetForRenderingChildren );
529 void GaussianBlurView::RemoveRenderTasks()
531 RenderTaskList taskList = Stage::GetCurrent().GetRenderTaskList();
533 taskList.RemoveTask(mRenderChildrenTask);
534 taskList.RemoveTask(mHorizBlurTask);
535 taskList.RemoveTask(mVertBlurTask);
536 taskList.RemoveTask(mCompositeTask);
539 void GaussianBlurView::Activate()
541 // make sure resources are allocated and start the render tasks processing
547 void GaussianBlurView::ActivateOnce()
549 DALI_ASSERT_ALWAYS(mBlurUserImage); // Only works with blurring image mode.
554 void GaussianBlurView::Deactivate()
556 // stop render tasks processing
557 // Note: render target resources are automatically freed since we set the Image::Unused flag
559 mRenderTargetForRenderingChildren.Reset();
560 mRenderTarget1.Reset();
561 mRenderTarget2.Reset();
566 void GaussianBlurView::SetBlurBellCurveWidth(float blurBellCurveWidth)
568 // a value of zero leads to undefined Gaussian weights, do not allow user to do this
569 mBlurBellCurveWidth = std::max( blurBellCurveWidth, 0.001f );
572 float GaussianBlurView::CalcGaussianWeight(float x)
574 return (1.0f / sqrt(2.0f * Math::PI * mBlurBellCurveWidth)) * exp(-(x * x) / (2.0f * mBlurBellCurveWidth * mBlurBellCurveWidth));
577 void GaussianBlurView::SetShaderConstants()
582 float w, totalWeights;
585 uvOffsets = new Vector2[mNumSamples + 1];
586 weights = new float[mNumSamples + 1];
588 totalWeights = weights[0] = CalcGaussianWeight(0);
589 uvOffsets[0].x = 0.0f;
590 uvOffsets[0].y = 0.0f;
592 for(i=0; i<mNumSamples >> 1; i++)
594 w = CalcGaussianWeight((float)(i + 1));
595 weights[(i << 1) + 1] = w;
596 weights[(i << 1) + 2] = w;
597 totalWeights += w * 2.0f;
599 // offset texture lookup to between texels, that way the bilinear filter in the texture hardware will average two samples with one lookup
600 ofs = ((float)(i << 1)) + 1.5f;
602 // get offsets from units of pixels into uv coordinates in [0..1]
603 float ofsX = ofs / mDownsampledWidth;
604 float ofsY = ofs / mDownsampledHeight;
605 uvOffsets[(i << 1) + 1].x = ofsX;
606 uvOffsets[(i << 1) + 1].y = ofsY;
608 uvOffsets[(i << 1) + 2].x = -ofsX;
609 uvOffsets[(i << 1) + 2].y = -ofsY;
612 for(i=0; i<mNumSamples; i++)
614 weights[i] /= totalWeights;
617 // set shader constants
618 Vector2 xAxis(1.0f, 0.0f);
619 Vector2 yAxis(0.0f, 1.0f);
620 for (i = 0; i < mNumSamples; ++i )
622 mHorizBlurActor.RegisterProperty( GetSampleOffsetsPropertyName( i ), uvOffsets[ i ] * xAxis );
623 mHorizBlurActor.RegisterProperty( GetSampleWeightsPropertyName( i ), weights[ i ] );
625 mVertBlurActor.RegisterProperty( GetSampleOffsetsPropertyName( i ), uvOffsets[ i ] * yAxis );
626 mVertBlurActor.RegisterProperty( GetSampleWeightsPropertyName( i ), weights[ i ] );
633 std::string GaussianBlurView::GetSampleOffsetsPropertyName( unsigned int index ) const
635 DALI_ASSERT_ALWAYS( index < mNumSamples );
637 std::ostringstream oss;
638 oss << "uSampleOffsets[" << index << "]";
642 std::string GaussianBlurView::GetSampleWeightsPropertyName( unsigned int index ) const
644 DALI_ASSERT_ALWAYS( index < mNumSamples );
646 std::ostringstream oss;
647 oss << "uSampleWeights[" << index << "]";
651 Dali::Toolkit::GaussianBlurView::GaussianBlurViewSignal& GaussianBlurView::FinishedSignal()
653 return mFinishedSignal;
656 void GaussianBlurView::OnRenderTaskFinished(Dali::RenderTask& renderTask)
658 Toolkit::GaussianBlurView handle( GetOwner() );
659 mFinishedSignal.Emit( handle );
662 } // namespace Internal
663 } // namespace Toolkit