/*

 * Copyright 2014 Google Inc.

 *

 * Use of this source code is governed by a BSD-style license that can be

 * found in the LICENSE file.

 */

#ifndef GrRectanizerSkyline_DEFINED

#define GrRectanizerSkyline_DEFINED

#include "include/private/SkTDArray.h"

#include "src/gpu/GrRectanizer.h"

// Pack rectangles and track the current silhouette

// Based, in part, on Jukka Jylanki's work at http://clb.demon.fi

//

// Mark this class final in an effort to avoid the vtable when this subclass is used explicitly.

class GrRectanizerSkyline final : public GrRectanizer {

public:

    GrRectanizerSkyline(int w, int h) : INHERITED(w, h) {

        this->reset();

    }

    ~GrRectanizerSkyline() final { }

    void reset() final {

        fAreaSoFar = 0;

        fSkyline.reset();

        SkylineSegment* seg = fSkyline.append(1);

        seg->fX = 0;

        seg->fY = 0;

        seg->fWidth = this->width();

    }

    bool addRect(int w, int h, SkIPoint16* loc) final;

    float percentFull() const final {

        return fAreaSoFar / ((float)this->width() * this->height());

    }

private:

    struct SkylineSegment {

        int  fX;

        int  fY;

        int  fWidth;

    };

    SkTDArray<SkylineSegment> fSkyline;

    int32_t fAreaSoFar;

    // Can a width x height rectangle fit in the free space represented by

    // the skyline segments >= 'skylineIndex'? If so, return true and fill in

    // 'y' with the y-location at which it fits (the x location is pulled from

    // 'skylineIndex's segment.

    bool rectangleFits(int skylineIndex, int width, int height, int* y) const;

    // Update the skyline structure to include a width x height rect located

    // at x,y.

    void addSkylineLevel(int skylineIndex, int x, int y, int width, int height);

    using INHERITED = GrRectanizer;

};

#endif