third_party/WebKit/Source/platform/scroll/ScrollTypes.h

/*
 * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef ScrollTypes_h
#define ScrollTypes_h

#include "platform/geometry/FloatSize.h"
#include "wtf/Assertions.h"

namespace blink {

enum ScrollDirection {
  ScrollUpIgnoringWritingMode,
  ScrollDownIgnoringWritingMode,
  ScrollLeftIgnoringWritingMode,
  ScrollRightIgnoringWritingMode,

  ScrollBlockDirectionBackward,
  ScrollBlockDirectionForward,
  ScrollInlineDirectionBackward,
  ScrollInlineDirectionForward
};

enum ScrollDirectionPhysical { ScrollUp, ScrollDown, ScrollLeft, ScrollRight };

enum ScrollType {
  UserScroll,
  ProgrammaticScroll,
  CompositorScroll,
  AnchoringScroll
};

// Convert logical scroll direction to physical. Physical scroll directions are
// unaffected.
inline ScrollDirectionPhysical toPhysicalDirection(ScrollDirection direction,
                                                   bool isVertical,
                                                   bool isFlipped) {
  switch (direction) {
    case ScrollBlockDirectionBackward: {
      if (isVertical) {
        if (!isFlipped)
          return ScrollUp;
        return ScrollDown;
      }
      if (!isFlipped)
        return ScrollLeft;
      return ScrollRight;
    }
    case ScrollBlockDirectionForward: {
      if (isVertical) {
        if (!isFlipped)
          return ScrollDown;
        return ScrollUp;
      }
      if (!isFlipped)
        return ScrollRight;
      return ScrollLeft;
    }
    case ScrollInlineDirectionBackward: {
      if (isVertical) {
        if (!isFlipped)
          return ScrollLeft;
        return ScrollRight;
      }
      if (!isFlipped)
        return ScrollUp;
      return ScrollDown;
    }
    case ScrollInlineDirectionForward: {
      if (isVertical) {
        if (!isFlipped)
          return ScrollRight;
        return ScrollLeft;
      }
      if (!isFlipped)
        return ScrollDown;
      return ScrollUp;
    }
    // Direction is already physical
    case ScrollUpIgnoringWritingMode:
      return ScrollUp;
    case ScrollDownIgnoringWritingMode:
      return ScrollDown;
    case ScrollLeftIgnoringWritingMode:
      return ScrollLeft;
    case ScrollRightIgnoringWritingMode:
      return ScrollRight;
    default:
      ASSERT_NOT_REACHED();
      break;
  }
  return ScrollUp;
}

inline ScrollDirection toScrollDirection(ScrollDirectionPhysical direction) {
  switch (direction) {
    case ScrollUp:
      return ScrollUpIgnoringWritingMode;
    case ScrollDown:
      return ScrollDownIgnoringWritingMode;
    case ScrollLeft:
      return ScrollLeftIgnoringWritingMode;
    case ScrollRight:
      return ScrollRightIgnoringWritingMode;
    default:
      ASSERT_NOT_REACHED();
      break;
  }
  return ScrollUpIgnoringWritingMode;
}

enum ScrollGranularity {
  ScrollByLine,
  ScrollByPage,
  ScrollByDocument,
  ScrollByPixel,
  ScrollByPrecisePixel
};

enum ScrollInertialPhase {
  ScrollInertialPhaseUnknown,
  ScrollInertialPhaseNonMomentum,
  ScrollInertialPhaseMomentum
};

enum ScrollbarOrientation { HorizontalScrollbar, VerticalScrollbar };

enum ScrollbarMode { ScrollbarAuto, ScrollbarAlwaysOff, ScrollbarAlwaysOn };

enum ScrollbarControlSize { RegularScrollbar, SmallScrollbar };

typedef unsigned ScrollbarControlState;

enum ScrollbarControlStateMask {
  ActiveScrollbarState = 1,
  EnabledScrollbarState = 1 << 1,
  PressedScrollbarState = 1 << 2
};

enum ScrollbarPart {
  NoPart = 0,
  BackButtonStartPart = 1,
  ForwardButtonStartPart = 1 << 1,
  BackTrackPart = 1 << 2,
  ThumbPart = 1 << 3,
  ForwardTrackPart = 1 << 4,
  BackButtonEndPart = 1 << 5,
  ForwardButtonEndPart = 1 << 6,
  ScrollbarBGPart = 1 << 7,
  TrackBGPart = 1 << 8,
  AllParts = 0xffffffff
};

enum ScrollbarOverlayStyle {
  ScrollbarOverlayStyleDefault,
  ScrollbarOverlayStyleDark,
  ScrollbarOverlayStyleLight
};

enum ScrollBehavior {
  ScrollBehaviorAuto,
  ScrollBehaviorInstant,
  ScrollBehaviorSmooth,
};

// The result of an attempt to scroll. If didScroll is true, then
// unusedScrollDelta gives the amount of the scroll delta that was not consumed
// by scrolling.
struct ScrollResult {
  STACK_ALLOCATED();
  explicit ScrollResult()
      : didScrollX(false),
        didScrollY(false),
        unusedScrollDeltaX(0),
        unusedScrollDeltaY(0) {}
  ScrollResult(bool didScrollX,
               bool didScrollY,
               float unusedScrollDeltaX,
               float unusedScrollDeltaY)
      : didScrollX(didScrollX),
        didScrollY(didScrollY),
        unusedScrollDeltaX(unusedScrollDeltaX),
        unusedScrollDeltaY(unusedScrollDeltaY) {}

  bool didScroll() { return didScrollX || didScrollY; }

  bool didScrollX;
  bool didScrollY;

  // In pixels.
  float unusedScrollDeltaX;
  float unusedScrollDeltaY;
};

inline FloatSize toScrollDelta(ScrollbarOrientation orientation, float delta) {
  return orientation == HorizontalScrollbar ? FloatSize(delta, 0.0f)
                                            : FloatSize(0.0f, delta);
}

inline FloatSize toScrollDelta(ScrollDirectionPhysical dir, float delta) {
  if (dir == ScrollUp || dir == ScrollLeft)
    delta = -delta;

  return (dir == ScrollLeft || dir == ScrollRight) ? FloatSize(delta, 0)
                                                   : FloatSize(0, delta);
}

typedef unsigned ScrollbarControlPartMask;

}  // namespace blink

#endif