29 lines
733 B
C++
29 lines
733 B
C++
/* $Id$ */
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#ifndef CMD_HELPER_H
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#define CMD_HELPER_H
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#include "direction.h"
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#include "macros.h"
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#include "road.h"
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template<uint N> static inline void ExtractValid();
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template<> static inline void ExtractValid<1>() {}
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template<typename T> struct ExtractBits;
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template<> struct ExtractBits<Axis> { static const uint Count = 1; };
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template<> struct ExtractBits<DiagDirection> { static const uint Count = 2; };
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template<> struct ExtractBits<RoadBits> { static const uint Count = 4; };
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template<typename T, uint N, typename U> static inline T Extract(U v)
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{
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// Check if there are enough bits in v
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ExtractValid<N + ExtractBits<T>::Count <= sizeof(U) * 8>();
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return (T)GB(v, N, ExtractBits<T>::Count);
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}
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#endif
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