libs/hwui/Snapshot.h - platform/frameworks/base - Gitiles

 /*
  * Copyright (C) 2010 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #ifndef ANDROID_HWUI_SNAPSHOT_H
 #define ANDROID_HWUI_SNAPSHOT_H

 #include <GLES2/gl2.h>
 #include <GLES2/gl2ext.h>

 #include <utils/RefBase.h>
 #include <ui/Region.h>

 #include <SkCanvas.h>

 #include "Layer.h"
 #include "Matrix.h"
 #include "Rect.h"

 namespace android {
 namespace uirenderer {

 /**
  * A snapshot holds information about the current state of the rendering
  * surface. A snapshot is usually created whenever the user calls save()
  * and discarded when the user calls restore(). Once a snapshot is created,
  * it can hold information for deferred rendering.
  *
  * Each snapshot has a link to a previous snapshot, indicating the previous
  * state of the renderer.
  */
 class Snapshot: public LightRefBase<Snapshot> {
 public:
     Snapshot(): flags(0), previous(NULL), layer(NULL), fbo(0), invisible(false), empty(false) {
         transform = &mTransformRoot;
         clipRect = &mClipRectRoot;
         region = NULL;
     }

     /**
      * Copies the specified snapshot/ The specified snapshot is stored as
      * the previous snapshot.
      */
     Snapshot(const sp<Snapshot>& s, int saveFlags):
             flags(0), previous(s), layer(NULL), fbo(s->fbo),
             invisible(s->invisible), empty(false), viewport(s->viewport), height(s->height) {
         if (saveFlags & SkCanvas::kMatrix_SaveFlag) {
             mTransformRoot.load(*s->transform);
             transform = &mTransformRoot;
         } else {
             transform = s->transform;
         }

         if (saveFlags & SkCanvas::kClip_SaveFlag) {
             mClipRectRoot.set(*s->clipRect);
             clipRect = &mClipRectRoot;
         } else {
             clipRect = s->clipRect;
         }

         if ((s->flags & Snapshot::kFlagClipSet) &&
                 !(s->flags & Snapshot::kFlagDirtyLocalClip)) {
             mLocalClip.set(s->mLocalClip);
         } else {
             flags |= Snapshot::kFlagDirtyLocalClip;
         }

         if (s->flags & Snapshot::kFlagFboTarget) {
             flags |= Snapshot::kFlagFboTarget;
             region = s->region;
         } else {
             region = NULL;
         }
     }

     /**
      * Various flags set on #flags.
      */
     enum Flags {
         /**
          * Indicates that the clip region was modified. When this
          * snapshot is restored so must the clip.
          */
         kFlagClipSet = 0x1,
         /**
          * Indicates that this snapshot was created when saving
          * a new layer.
          */
         kFlagIsLayer = 0x2,
         /**
          * Indicates that this snapshot is a special type of layer
          * backed by an FBO. This flag only makes sense when the
          * flag kFlagIsLayer is also set.
          */
         kFlagIsFboLayer = 0x4,
         /**
          * Indicates that the local clip should be recomputed.
          */
         kFlagDirtyLocalClip = 0x8,
         /**
          * Indicates that this snapshot has changed the ortho matrix.
          */
         kFlagDirtyOrtho = 0x10,
         /**
          * Indicates that this snapshot or an ancestor snapshot is
          * an FBO layer.
          */
         kFlagFboTarget = 0x20
     };

     /**
      * Modifies the current clip with the new clip rectangle and
      * the specified operation. The specified rectangle is transformed
      * by this snapshot's trasnformation.
      */
     bool clip(float left, float top, float right, float bottom,
             SkRegion::Op op = SkRegion::kIntersect_Op) {
         Rect r(left, top, right, bottom);
         transform->mapRect(r);
         return clipTransformed(r, op);
     }

     /**
      * Modifies the current clip with the new clip rectangle and
      * the specified operation. The specified rectangle is considered
      * already transformed.
      */
     bool clipTransformed(const Rect& r, SkRegion::Op op = SkRegion::kIntersect_Op) {
         bool clipped = false;

         // NOTE: The unimplemented operations require support for regions
         // Supporting regions would require using a stencil buffer instead
         // of the scissor. The stencil buffer itself is not too expensive
         // (memory cost excluded) but on fillrate limited devices, managing
         // the stencil might have a negative impact on the framerate.
         switch (op) {
             case SkRegion::kDifference_Op:
                 break;
             case SkRegion::kIntersect_Op:
                 clipped = clipRect->intersect(r);
                 break;
             case SkRegion::kUnion_Op:
                 clipped = clipRect->unionWith(r);
                 break;
             case SkRegion::kXOR_Op:
                 break;
             case SkRegion::kReverseDifference_Op:
                 break;
             case SkRegion::kReplace_Op:
                 clipRect->set(r);
                 clipped = true;
                 break;
         }

         if (clipped) {
             flags |= Snapshot::kFlagClipSet | Snapshot::kFlagDirtyLocalClip;
         }

         return clipped;
     }

     /**
      * Sets the current clip.
      */
     void setClip(float left, float top, float right, float bottom) {
         clipRect->set(left, top, right, bottom);
         flags |= Snapshot::kFlagClipSet | Snapshot::kFlagDirtyLocalClip;
     }

     const Rect& getLocalClip() {
         if (flags & Snapshot::kFlagDirtyLocalClip) {
             mat4 inverse;
             inverse.loadInverse(*transform);

             mLocalClip.set(*clipRect);
             inverse.mapRect(mLocalClip);

             flags &= ~Snapshot::kFlagDirtyLocalClip;
         }
         return mLocalClip;
     }

     void resetTransform(float x, float y, float z) {
         transform = &mTransformRoot;
         transform->loadTranslate(x, y, z);
     }

     void resetClip(float left, float top, float right, float bottom) {
         clipRect = &mClipRectRoot;
         clipRect->set(left, top, right, bottom);
         flags |= Snapshot::kFlagClipSet | Snapshot::kFlagDirtyLocalClip;
     }

     bool isIgnored() const {
         return invisible || empty;
     }

     /**
      * Dirty flags.
      */
     int flags;

     /**
      * Previous snapshot.
      */
     sp<Snapshot> previous;

     /**
      * Only set when the flag kFlagIsLayer is set.
      */
     Layer* layer;

     /**
      * Only set when the flag kFlagIsFboLayer is set.
      */
     GLuint fbo;

     /**
      * Indicates that this snapshot is invisible and nothing should be drawn
      * inside it. This flag is set only when the layer clips drawing to its
      * bounds and is passed to subsequent snapshots.
      */
     bool invisible;

     /**
      * If set to true, the layer will not be composited. This is similar to
      * invisible but this flag is not passed to subsequent snapshots.
      */
     bool empty;

     /**
      * Current viewport.
      */
     Rect viewport;

     /**
      * Height of the framebuffer the snapshot is rendering into.
      */
     int height;

     /**
      * Contains the previous ortho matrix.
      */
     mat4 orthoMatrix;

     /**
      * Local transformation. Holds the current translation, scale and
      * rotation values.
      */
     mat4* transform;

     /**
      * Current clip region. The clip is stored in canvas-space coordinates,
      * (screen-space coordinates in the regular case.)
      */
     Rect* clipRect;

     /**
      * The ancestor layer's dirty region.
      */
     Region* region;

 private:
     mat4 mTransformRoot;
     Rect mClipRectRoot;
     Rect mLocalClip;

 }; // class Snapshot

 }; // namespace uirenderer
 }; // namespace android

 #endif // ANDROID_HWUI_SNAPSHOT_H
	/*
	* Copyright (C) 2010 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#ifndef ANDROID_HWUI_SNAPSHOT_H
	#define ANDROID_HWUI_SNAPSHOT_H

	#include <GLES2/gl2.h>
	#include <GLES2/gl2ext.h>

	#include <utils/RefBase.h>
	#include <ui/Region.h>

	#include <SkCanvas.h>

	#include "Layer.h"
	#include "Matrix.h"
	#include "Rect.h"

	namespace android {
	namespace uirenderer {

	/**
	* A snapshot holds information about the current state of the rendering
	* surface. A snapshot is usually created whenever the user calls save()
	* and discarded when the user calls restore(). Once a snapshot is created,
	* it can hold information for deferred rendering.
	*
	* Each snapshot has a link to a previous snapshot, indicating the previous
	* state of the renderer.
	*/
	class Snapshot: public LightRefBase<Snapshot> {
	public:
	Snapshot(): flags(0), previous(NULL), layer(NULL), fbo(0), invisible(false), empty(false) {
	transform = &mTransformRoot;
	clipRect = &mClipRectRoot;
	region = NULL;
	}

	/**
	* Copies the specified snapshot/ The specified snapshot is stored as
	* the previous snapshot.
	*/
	Snapshot(const sp<Snapshot>& s, int saveFlags):
	flags(0), previous(s), layer(NULL), fbo(s->fbo),
	invisible(s->invisible), empty(false), viewport(s->viewport), height(s->height) {
	if (saveFlags & SkCanvas::kMatrix_SaveFlag) {
	mTransformRoot.load(*s->transform);
	transform = &mTransformRoot;
	} else {
	transform = s->transform;
	}

	if (saveFlags & SkCanvas::kClip_SaveFlag) {
	mClipRectRoot.set(*s->clipRect);
	clipRect = &mClipRectRoot;
	} else {
	clipRect = s->clipRect;
	}

	if ((s->flags & Snapshot::kFlagClipSet) &&
	!(s->flags & Snapshot::kFlagDirtyLocalClip)) {
	mLocalClip.set(s->mLocalClip);
	} else {
	flags \|= Snapshot::kFlagDirtyLocalClip;
	}

	if (s->flags & Snapshot::kFlagFboTarget) {
	flags \|= Snapshot::kFlagFboTarget;
	region = s->region;
	} else {
	region = NULL;
	}
	}

	/**
	* Various flags set on #flags.
	*/
	enum Flags {
	/**
	* Indicates that the clip region was modified. When this
	* snapshot is restored so must the clip.
	*/
	kFlagClipSet = 0x1,
	/**
	* Indicates that this snapshot was created when saving
	* a new layer.
	*/
	kFlagIsLayer = 0x2,
	/**
	* Indicates that this snapshot is a special type of layer
	* backed by an FBO. This flag only makes sense when the
	* flag kFlagIsLayer is also set.
	*/
	kFlagIsFboLayer = 0x4,
	/**
	* Indicates that the local clip should be recomputed.
	*/
	kFlagDirtyLocalClip = 0x8,
	/**
	* Indicates that this snapshot has changed the ortho matrix.
	*/
	kFlagDirtyOrtho = 0x10,
	/**
	* Indicates that this snapshot or an ancestor snapshot is
	* an FBO layer.
	*/
	kFlagFboTarget = 0x20
	};

	/**
	* Modifies the current clip with the new clip rectangle and
	* the specified operation. The specified rectangle is transformed
	* by this snapshot's trasnformation.
	*/
	bool clip(float left, float top, float right, float bottom,
	SkRegion::Op op = SkRegion::kIntersect_Op) {
	Rect r(left, top, right, bottom);
	transform->mapRect(r);
	return clipTransformed(r, op);
	}

	/**
	* Modifies the current clip with the new clip rectangle and
	* the specified operation. The specified rectangle is considered
	* already transformed.
	*/
	bool clipTransformed(const Rect& r, SkRegion::Op op = SkRegion::kIntersect_Op) {
	bool clipped = false;

	// NOTE: The unimplemented operations require support for regions
	// Supporting regions would require using a stencil buffer instead
	// of the scissor. The stencil buffer itself is not too expensive
	// (memory cost excluded) but on fillrate limited devices, managing
	// the stencil might have a negative impact on the framerate.
	switch (op) {
	case SkRegion::kDifference_Op:
	break;
	case SkRegion::kIntersect_Op:
	clipped = clipRect->intersect(r);
	break;
	case SkRegion::kUnion_Op:
	clipped = clipRect->unionWith(r);
	break;
	case SkRegion::kXOR_Op:
	break;
	case SkRegion::kReverseDifference_Op:
	break;
	case SkRegion::kReplace_Op:
	clipRect->set(r);
	clipped = true;
	break;
	}

	if (clipped) {
	flags \|= Snapshot::kFlagClipSet \| Snapshot::kFlagDirtyLocalClip;
	}

	return clipped;
	}

	/**
	* Sets the current clip.
	*/
	void setClip(float left, float top, float right, float bottom) {
	clipRect->set(left, top, right, bottom);
	flags \|= Snapshot::kFlagClipSet \| Snapshot::kFlagDirtyLocalClip;
	}

	const Rect& getLocalClip() {
	if (flags & Snapshot::kFlagDirtyLocalClip) {
	mat4 inverse;
	inverse.loadInverse(*transform);

	mLocalClip.set(*clipRect);
	inverse.mapRect(mLocalClip);

	flags &= ~Snapshot::kFlagDirtyLocalClip;
	}
	return mLocalClip;
	}

	void resetTransform(float x, float y, float z) {
	transform = &mTransformRoot;
	transform->loadTranslate(x, y, z);
	}

	void resetClip(float left, float top, float right, float bottom) {
	clipRect = &mClipRectRoot;
	clipRect->set(left, top, right, bottom);
	flags \|= Snapshot::kFlagClipSet \| Snapshot::kFlagDirtyLocalClip;
	}

	bool isIgnored() const {
	return invisible \|\| empty;
	}

	/**
	* Dirty flags.
	*/
	int flags;

	/**
	* Previous snapshot.
	*/
	sp<Snapshot> previous;

	/**
	* Only set when the flag kFlagIsLayer is set.
	*/
	Layer* layer;

	/**
	* Only set when the flag kFlagIsFboLayer is set.
	*/
	GLuint fbo;

	/**
	* Indicates that this snapshot is invisible and nothing should be drawn
	* inside it. This flag is set only when the layer clips drawing to its
	* bounds and is passed to subsequent snapshots.
	*/
	bool invisible;

	/**
	* If set to true, the layer will not be composited. This is similar to
	* invisible but this flag is not passed to subsequent snapshots.
	*/
	bool empty;

	/**
	* Current viewport.
	*/
	Rect viewport;

	/**
	* Height of the framebuffer the snapshot is rendering into.
	*/
	int height;

	/**
	* Contains the previous ortho matrix.
	*/
	mat4 orthoMatrix;

	/**
	* Local transformation. Holds the current translation, scale and
	* rotation values.
	*/
	mat4* transform;

	/**
	* Current clip region. The clip is stored in canvas-space coordinates,
	* (screen-space coordinates in the regular case.)
	*/
	Rect* clipRect;

	/**
	* The ancestor layer's dirty region.
	*/
	Region* region;

	private:
	mat4 mTransformRoot;
	Rect mClipRectRoot;
	Rect mLocalClip;

	}; // class Snapshot

	}; // namespace uirenderer
	}; // namespace android

	#endif // ANDROID_HWUI_SNAPSHOT_H