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// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CC_INPUT_TOUCH_ACTION_H_
#define CC_INPUT_TOUCH_ACTION_H_
#include <cstdlib>
#include "base/notreached.h"
namespace cc {
// The current touch action specifies what accelerated browser operations
// (panning and zooming) are currently permitted via touch input.
// See http://www.w3.org/TR/pointerevents/#the-touch-action-css-property.
// This is intended to be the single canonical definition of the enum, it's used
// elsewhere in both Blink and content since touch action logic spans those
// subsystems.
const size_t kTouchActionBits = 10;
enum class TouchAction {
// No scrolling or zooming allowed.
kNone = 0x0,
kPanLeft = 0x1,
kPanRight = 0x2,
kPanX = kPanLeft | kPanRight,
kPanUp = 0x4,
kPanDown = 0x8,
kPanY = kPanUp | kPanDown,
kPan = kPanX | kPanY,
kPinchZoom = 0x10,
kDoubleTapZoom = 0x20,
// Used by swipe to move cursor feature. This is only used internally
// for swipe to move cursor feature and it is not a web-visible value. When
// an element have this bit or doesn't have kPanX, we will disable swipe to
// move cursor feature for that element. When the element is contenteditable
// and it doesn't have a horizontal scrollable ancestor (including
// itself), we don't set this bit.
kInternalPanXScrolls = 0x40,
// This is used internally by stylus handwriting feature. Stylus writing would
// not be started when this bit is set. When the element is non-password edit
// field and has kPan, we don't set this bit.
kInternalNotWritable = 0x80,
// TODO(crbug.com/382525574): This value is currently being used to measure
// how many pages would lose handwriting if handwriting were to ship as a new
// touch action value as describedd in the linked bug.
kInternalHandwriting = 0x100,
// This value will be used to measure how many pages will lose handwriting
// if it follows the panning rules for re-enablement.
kInternalHandwritingPanningRules = 0x200,
kManipulation = kPan | kPinchZoom | kInternalHandwriting |
kInternalHandwritingPanningRules,
kAuto = kManipulation | kDoubleTapZoom | kInternalPanXScrolls |
kInternalNotWritable | kInternalHandwriting |
kInternalHandwritingPanningRules,
kMax = (1 << kTouchActionBits) - 1
};
inline TouchAction operator|(TouchAction a, TouchAction b) {
return static_cast<TouchAction>(static_cast<int>(a) | static_cast<int>(b));
}
inline TouchAction& operator|=(TouchAction& a, TouchAction b) {
return a = a | b;
}
inline TouchAction operator&(TouchAction a, TouchAction b) {
return static_cast<TouchAction>(static_cast<int>(a) & static_cast<int>(b));
}
inline TouchAction& operator&=(TouchAction& a, TouchAction b) {
return a = a & b;
}
inline TouchAction operator~(TouchAction touch_action) {
return static_cast<TouchAction>(~static_cast<int>(touch_action));
}
inline const char* TouchActionToString(TouchAction touch_action) {
// we skip printing internal panx scrolls since it's not a web exposed touch
// action field.
touch_action &= ~TouchAction::kInternalPanXScrolls;
// we skip printing kInternalNotWritable since it's not a web exposed
// touch action field.
touch_action &= ~TouchAction::kInternalNotWritable;
// Until handwriting is a web exposed feature, the combination of
// non-handwriting bits should result in values of auto / manipulation in the
// exposed CSS value.
// TODO(crbug.com/382525574): Launch or clean up kHandwriting.
touch_action &= ~(TouchAction::kInternalHandwriting |
TouchAction::kInternalHandwritingPanningRules);
switch (static_cast<int>(touch_action)) {
case 0:
return "NONE";
case 1:
return "PAN_LEFT";
case 2:
return "PAN_RIGHT";
case 3:
return "PAN_X";
case 4:
return "PAN_UP";
case 5:
return "PAN_LEFT_PAN_UP";
case 6:
return "PAN_RIGHT_PAN_UP";
case 7:
return "PAN_X_PAN_UP";
case 8:
return "PAN_DOWN";
case 9:
return "PAN_LEFT_PAN_DOWN";
case 10:
return "PAN_RIGHT_PAN_DOWN";
case 11:
return "PAN_X_PAN_DOWN";
case 12:
return "PAN_Y";
case 13:
return "PAN_LEFT_PAN_Y";
case 14:
return "PAN_RIGHT_PAN_Y";
case 15:
return "PAN_X_PAN_Y";
case 16:
return "PINCH_ZOOM";
case 17:
return "PAN_LEFT_PINCH_ZOOM";
case 18:
return "PAN_RIGHT_PINCH_ZOOM";
case 19:
return "PAN_X_PINCH_ZOOM";
case 20:
return "PAN_UP_PINCH_ZOOM";
case 21:
return "PAN_LEFT_PAN_UP_PINCH_ZOOM";
case 22:
return "PAN_RIGHT_PAN_UP_PINCH_ZOOM";
case 23:
return "PAN_X_PAN_UP_PINCH_ZOOM";
case 24:
return "PAN_DOWN_PINCH_ZOOM";
case 25:
return "PAN_LEFT_PAN_DOWN_PINCH_ZOOM";
case 26:
return "PAN_RIGHT_PAN_DOWN_PINCH_ZOOM";
case 27:
return "PAN_X_PAN_DOWN_PINCH_ZOOM";
case 28:
return "PAN_Y_PINCH_ZOOM";
case 29:
return "PAN_LEFT_PAN_Y_PINCH_ZOOM";
case 30:
return "PAN_RIGHT_PAN_Y_PINCH_ZOOM";
case 31:
return "MANIPULATION";
case 32:
return "DOUBLE_TAP_ZOOM";
case 33:
return "PAN_LEFT_DOUBLE_TAP_ZOOM";
case 34:
return "PAN_RIGHT_DOUBLE_TAP_ZOOM";
case 35:
return "PAN_X_DOUBLE_TAP_ZOOM";
case 36:
return "PAN_UP_DOUBLE_TAP_ZOOM";
case 37:
return "PAN_LEFT_PAN_UP_DOUBLE_TAP_ZOOM";
case 38:
return "PAN_RIGHT_PAN_UP_DOUBLE_TAP_ZOOM";
case 39:
return "PAN_X_PAN_UP_DOUBLE_TAP_ZOOM";
case 40:
return "PAN_DOWN_DOUBLE_TAP_ZOOM";
case 41:
return "PAN_LEFT_PAN_DOWN_DOUBLE_TAP_ZOOM";
case 42:
return "PAN_RIGHT_PAN_DOWN_DOUBLE_TAP_ZOOM";
case 43:
return "PAN_X_PAN_DOWN_DOUBLE_TAP_ZOOM";
case 44:
return "PAN_Y_DOUBLE_TAP_ZOOM";
case 45:
return "PAN_LEFT_PAN_Y_DOUBLE_TAP_ZOOM";
case 46:
return "PAN_RIGHT_PAN_Y_DOUBLE_TAP_ZOOM";
case 47:
return "PAN_X_PAN_Y_DOUBLE_TAP_ZOOM";
case 48:
return "PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 49:
return "PAN_LEFT_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 50:
return "PAN_RIGHT_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 51:
return "PAN_X_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 52:
return "PAN_UP_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 53:
return "PAN_LEFT_PAN_UP_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 54:
return "PAN_RIGHT_PAN_UP_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 55:
return "PAN_X_PAN_UP_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 56:
return "PAN_DOWN_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 57:
return "PAN_LEFT_PAN_DOWN_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 58:
return "PAN_RIGHT_PAN_DOWN_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 59:
return "PAN_X_PAN_DOWN_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 60:
return "PAN_Y_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 61:
return "PAN_LEFT_PAN_Y_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 62:
return "PAN_RIGHT_PAN_Y_PINCH_ZOOM_DOUBLE_TAP_ZOOM";
case 63:
return "AUTO";
}
NOTREACHED();
}
} // namespace cc
#endif // CC_INPUT_TOUCH_ACTION_H_
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