replicant-frameworks_native/include/utils/BitSet.h
Jeff Brown fa773aa745 Use touch pad gestures to manipulate the pointer.
1. Single finger tap performs a click.
2. Single finger movement moves the pointer (hovers).
3. Button press plus movement performs click or drag.
   While dragging, the pointer follows the finger that is moving
   fastest.  This is important if there are additional fingers
   down on the touch pad for the purpose of applying force
   to an integrated button underneath.
4. Two fingers near each other moving in the same direction
   are coalesced as a swipe gesture under the pointer.
5. Two or more fingers moving in arbitrary directions are
   transformed into touches in the vicinity of the pointer.
   This makes scale/zoom and rotate gestures possible.

Added a native VelocityTracker implementation to enable intelligent
switching of the active pointer during drags.

Change-Id: I5ada57e7f2bdb9b0a791843eb354a8c706b365dc
2011-03-14 14:12:03 -07:00

77 lines
2.5 KiB
C++

/*
* 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 UTILS_BITSET_H
#define UTILS_BITSET_H
#include <stdint.h>
/*
* Contains some bit manipulation helpers.
*/
namespace android {
// A simple set of 32 bits that can be individually marked or cleared.
struct BitSet32 {
uint32_t value;
inline BitSet32() : value(0) { }
explicit inline BitSet32(uint32_t value) : value(value) { }
// Gets the value associated with a particular bit index.
static inline uint32_t valueForBit(uint32_t n) { return 0x80000000 >> n; }
// Clears the bit set.
inline void clear() { value = 0; }
// Returns the number of marked bits in the set.
inline uint32_t count() const { return __builtin_popcount(value); }
// Returns true if the bit set does not contain any marked bits.
inline bool isEmpty() const { return ! value; }
// Returns true if the specified bit is marked.
inline bool hasBit(uint32_t n) const { return value & valueForBit(n); }
// Marks the specified bit.
inline void markBit(uint32_t n) { value |= valueForBit(n); }
// Clears the specified bit.
inline void clearBit(uint32_t n) { value &= ~ valueForBit(n); }
// Finds the first marked bit in the set.
// Result is undefined if all bits are unmarked.
inline uint32_t firstMarkedBit() const { return __builtin_clz(value); }
// Finds the first unmarked bit in the set.
// Result is undefined if all bits are marked.
inline uint32_t firstUnmarkedBit() const { return __builtin_clz(~ value); }
// Gets the index of the specified bit in the set, which is the number of
// marked bits that appear before the specified bit.
inline uint32_t getIndexOfBit(uint32_t n) const {
return __builtin_popcount(value & ~(0xffffffffUL >> n));
}
inline bool operator== (const BitSet32& other) const { return value == other.value; }
inline bool operator!= (const BitSet32& other) const { return value != other.value; }
};
} // namespace android
#endif // UTILS_BITSET_H