gfx/skia/skia/include/utils/SkLayer.h
author Wes Kocher <wkocher@mozilla.com>
Wed, 10 May 2017 10:01:18 -0700
changeset 407965 ce2218406119c36a551e3faea4e192186ee46cc5
permissions -rw-r--r--
Backed out 9 changesets (bug 1340627) for graphical glitches a=backout Backed out changeset 0b1371055c7f (bug 1340627) Backed out changeset f152be1fadb7 (bug 1340627) Backed out changeset c691e2ab6a0c (bug 1340627) Backed out changeset 3cb4bceb8d79 (bug 1340627) Backed out changeset 026aadd76d06 (bug 1340627) Backed out changeset fdbd5d281287 (bug 1340627) Backed out changeset 75fb0d9858a9 (bug 1340627) Backed out changeset 0d4ec7d38a00 (bug 1340627) Backed out changeset af6f19870b2a (bug 1340627) MozReview-Commit-ID: 9dHr7xMZezY


/*
 * Copyright 2010 The Android Open Source Project
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */


#ifndef SkLayer_DEFINED
#define SkLayer_DEFINED

#include "../private/SkTDArray.h"
#include "SkRefCnt.h"
#include "SkColor.h"
#include "SkMatrix.h"
#include "SkPoint.h"
#include "SkRect.h"
#include "SkSize.h"

class SkCanvas;

class SkLayer : public SkRefCnt {

public:
    

    SkLayer();
    SkLayer(const SkLayer&);
    virtual ~SkLayer();

    bool isInheritFromRootTransform() const;
    SkScalar getOpacity() const { return m_opacity; }
    const SkSize& getSize() const { return m_size; }
    const SkPoint& getPosition() const { return m_position; }
    const SkPoint& getAnchorPoint() const { return m_anchorPoint; }
    const SkMatrix& getMatrix() const { return fMatrix; }
    const SkMatrix& getChildrenMatrix() const { return fChildrenMatrix; }

    SkScalar getWidth() const { return m_size.width(); }
    SkScalar getHeight() const { return m_size.height(); }

    void setInheritFromRootTransform(bool);
    void setOpacity(SkScalar opacity) { m_opacity = opacity; }
    void setSize(SkScalar w, SkScalar h) { m_size.set(w, h); }
    void setPosition(SkScalar x, SkScalar y) { m_position.set(x, y); }
    void setAnchorPoint(SkScalar x, SkScalar y) { m_anchorPoint.set(x, y); }
    void setMatrix(const SkMatrix&);
    void setChildrenMatrix(const SkMatrix&);

    // children

    /** Return the number of layers in our child list.
     */
    int countChildren() const;

    /** Return the child at the specified index (starting at 0). This does not
        affect the reference count of the child.
     */
    SkLayer* getChild(int index) const;

    /** Add this layer to our child list at the end (top-most), and ref() it.
        If it was already in another hierarchy, remove it from that list.
        Return the new child.
     */
    SkLayer* addChild(SkLayer* child);

    /** Remove this layer from its parent's list (or do nothing if it has no
        parent.) If it had a parent, then unref() is called.
     */
    void detachFromParent();

    /** Remove, and unref(), all of the layers in our child list.
     */
    void removeChildren();

    /** Return our parent layer, or NULL if we have none.
     */
    SkLayer* getParent() const { return fParent; }

    /** Return the root layer in this hiearchy. If this layer is the root
        (i.e. has no parent), then this returns itself.
     */
    SkLayer* getRootLayer() const;

    // coordinate system transformations

    /** Return, in matrix, the matix transfomations that are applied locally
        when this layer draws (i.e. its position and matrix/anchorPoint).
        This does not include the childrenMatrix, since that is only applied
        after this layer draws (but before its children draw).
     */
    void getLocalTransform(SkMatrix* matrix) const;

    /** Return, in matrix, the concatenation of transforms that are applied
        from this layer's root parent to the layer itself.
        This is the matrix that is applied to the layer during drawing.
     */
    void localToGlobal(SkMatrix* matrix) const;

    // paint method

    void draw(SkCanvas*, SkScalar opacity);
    void draw(SkCanvas* canvas) {
        this->draw(canvas, SK_Scalar1);
    }

protected:
    virtual void onDraw(SkCanvas*, SkScalar opacity);

private:
    enum Flags {
        kInheritFromRootTransform_Flag = 0x01
    };

    SkLayer*    fParent;
    SkScalar    m_opacity;
    SkSize      m_size;
    SkPoint     m_position;
    SkPoint     m_anchorPoint;
    SkMatrix    fMatrix;
    SkMatrix    fChildrenMatrix;
    uint32_t    fFlags;

    SkTDArray<SkLayer*> m_children;

    typedef SkRefCnt INHERITED;
};

#endif