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/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#ifndef STARTREK_FIXEDINT_H
#define STARTREK_FIXEDINT_H
#include "common/serializer.h"
#include "startrek/common.h"
namespace StarTrek {
/**
* Signed fixed-point number.
*/
template<typename T, uint totalBits, uint decimalBits>
class TFixedInt : Common::Serializable {
const static int max = (1 << (totalBits - decimalBits - 1)) - 1;
const static int min = -max - 1;
T val;
public:
static TFixedInt fromRaw(T raw) {
TFixedInt ret;
ret.val = raw;
return ret;
}
TFixedInt() : val(0) {}
TFixedInt(double d) {
assert(d >= min && d <= max); // FIXME: downgrade this to a warning?
val = (T)(d * (1 << decimalBits));
}
/**
* Constructor from other fixed-point formats.
*/
template<typename T2, uint otherTB, uint otherDB>
explicit TFixedInt<T, totalBits, decimalBits>(const TFixedInt<T2, otherTB, otherDB> &fi) {
int diff = otherDB - decimalBits;
if (otherDB >= decimalBits)
val = fi.raw() >> diff;
else
val = fi.raw() << (-diff);
}
T raw() const {
return val;
}
int16 toInt() const {
return val >> decimalBits;
}
double toDouble() const {
return ((double)val) / (1 << decimalBits);
}
TFixedInt operator-() const {
return fromRaw(-val);
}
/**
* Multiplication with an int, with the result being an int. Use this if the result
* might exceed the capacity of this type.
*/
int16 multToInt(int32 i) {
return ((int32)(val * i)) >> decimalBits;
}
/**
* Multiplication with an int, with the result being the same type.
*/
TFixedInt operator*(int32 i) const {
return fromRaw(val * i);
}
/**
* Multiplication with a FixedInt, with the result being the same type.
*/
TFixedInt operator*(const TFixedInt &f) const {
return fromRaw(((int32)(val * f.val)) >> decimalBits);
}
/**
* Division with an int, with the result being the same type.
*/
TFixedInt operator/(int32 i) const {
return fromRaw(val / i);
}
TFixedInt operator+(const TFixedInt &f) const {
return fromRaw(val + f.val);
}
TFixedInt operator-(const TFixedInt &f) const {
return fromRaw(val - f.val);
}
void operator+=(const TFixedInt &f) {
val += f.val;
}
void operator-=(const TFixedInt &f) {
val -= f.val;
}
bool operator==(double d) const {
return toDouble() == d;
}
bool operator!=(double d) const {
return toDouble() != d;
}
bool operator<(double d) const {
return toDouble() < d;
}
bool operator<=(double d) const {
return toDouble() <= d;
}
bool operator>(double d) const {
return toDouble() > d;
}
bool operator>=(double d) const {
return toDouble() >= d;
}
bool operator==(const TFixedInt &f) const {
return val == f.val;
}
bool operator!=(const TFixedInt &f) const {
return val != f.val;
}
bool operator<(const TFixedInt &f) const {
return val < f.val;
}
bool operator<=(const TFixedInt &f) const {
return val <= f.val;
}
bool operator>(const TFixedInt &f) const {
return val > f.val;
}
bool operator>=(const TFixedInt &f) const {
return val >= f.val;
}
void saveLoadWithSerializer(Common::Serializer &ser) {
if (totalBits == 16)
ser.syncAsSint16LE(val);
else if (totalBits == 32)
ser.syncAsSint32LE(val);
else
error("Unsupported bit size for TFixedInt");
}
};
template<typename T, uint totalBits, uint decimalBits>
int32 operator*(const int16 lhs, const TFixedInt<T, totalBits, decimalBits> &rhs) {
return rhs * lhs;
}
// Fixed-point (2.14) number (between -1 and 1)
typedef TFixedInt<int16, 16, 14> Fixed14;
// Fixed-point (8.8) number
typedef TFixedInt<int16, 16, 8> Fixed8;
// Fixed-point (16.16) number
typedef TFixedInt<int32, 32, 16> Fixed16;
typedef Fixed8 Angle;
} // End of namespace StarTrek
#endif
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