CWE-ou-minkata/Sources/Plasma/CoreLib/plLoadMask.h

/*==LICENSE==*

CyanWorlds.com Engine - MMOG client, server and tools
Copyright (C) 2011  Cyan Worlds, Inc.

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 3 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, see <http://www.gnu.org/licenses/>.

You can contact Cyan Worlds, Inc. by email legal@cyan.com
 or by snail mail at:
      Cyan Worlds, Inc.
      14617 N Newport Hwy
      Mead, WA   99021

*==LICENSE==*/

#ifndef plLoadMask_inc
#define plLoadMask_inc

#include "hsTypes.h"

template <class T> class hsTArray;
class hsStream;

class plLoadMask
{
public:
    enum {
        kMaxCap = 1
    };
protected:
    static UInt8    fGlobalQuality;
    static UInt8    fGlobalCapability;
    union {
        UInt8           fQuality[kMaxCap+1];
        UInt16          fMask;
    };

    static void SetGlobalQuality(int q) { fGlobalQuality = IBitToMask(q); }
    static void SetGlobalCapability(int c) { if( c > kMaxCap ) c = kMaxCap; else if( c < 0 ) c = 0; fGlobalCapability = c; }

    static UInt8 IBitToMask(int b) { hsAssert(b<8, "LoadMask: bit too large for byte"); return (1 << b); }

    friend class plQuality;
public:
    // Change this to a for loop on kMaxCap+1 if we ever get more caps.
    plLoadMask() { fQuality[0] = fQuality[1] = 0xff; }
    plLoadMask(UInt8 qLo, UInt8 qHi) { fQuality[0] = qLo; fQuality[1] = qHi; }
    ~plLoadMask() {}

    hsBool      DontLoad() const { return !(fQuality[fGlobalCapability] & fGlobalQuality); }

    hsBool      NeverLoads() const { return !(fQuality[0] && fQuality[1]); }

    hsBool      IsUsed() const { return (fQuality[0] != UInt8(-1)) || (fQuality[1] != UInt8(-1));   }

    hsBool      MatchesQuality(int q) const { return (IBitToMask(q) & (fQuality[0] | fQuality[1])) != 0; }
    hsBool      MatchesCapability(int c) const { return fQuality[c] != 0; }
    hsBool      MatchesQualityAndCapability(int q, int c) const { return IBitToMask(q) & fQuality[c]; }

    hsBool      MatchesCurrentQuality() const { return MatchesQuality(fGlobalQuality); }
    hsBool      MatchesCurrentCapability() const { return MatchesCapability(fGlobalCapability); }
    hsBool      MatchesCurrent() const { return !DontLoad(); }

    UInt8       GetQualityMask(int cap) const { return fQuality[cap]; }

    plLoadMask&     SetMask(UInt8 lo, UInt8 hi) { fQuality[0] = lo; fQuality[1] = hi; return *this; }
    plLoadMask&     SetNever() { return SetMask(0,0); }
    plLoadMask&     SetAlways() { return SetMask(UInt8(-1), UInt8(-1)); }

    plLoadMask& operator|=(const plLoadMask& m) { fMask |= m.fMask; return *this; }
    plLoadMask& operator&=(const plLoadMask& m) { fMask &= m.fMask; return *this; }

    int operator==(const plLoadMask& m) const { return fMask == m.fMask; }
    int operator!=(const plLoadMask& m) const { return !(*this == m); }

    // Only useful for sorting.
    int operator<(const plLoadMask& m) const { return fMask < m.fMask; }

    friend plLoadMask operator|(const plLoadMask& lhs, const plLoadMask& rhs) { plLoadMask r(lhs); r |= rhs; return r; }
    friend plLoadMask operator&(const plLoadMask& lhs, const plLoadMask& rhs) { plLoadMask r(lhs); r &= rhs; return r; }

    void        Read(hsStream* s);
    void        Write(hsStream* s) const;

    static const plLoadMask     kAlways;


    // Input lists are in order of preference, i.e. if rep[0] and rep[1] are both loadable based
    // on the current settings, only rep[0] will be loaded. This implies some rules
    // to avoid wasted reps (reps that would never get loaded). Basically:
    //  if( i < j ) then
    //      (quals[i] > quals[j]) || (caps[i] > caps[j])
    //
    // It doesn't break anything if that condition isn't met, it just means
    // the latter one will never get loaded (have a load mask of zero).
    // So, just to be a pal, we'll detect that condition and return based on it.
    // i.e. Return true on invalid input (something will never get loaded).
    // 
    // You can also pre-validate your input with ValidateReps, and/or validate
    // the output with ValidateMasks. The return value is a bitmask of which
    // items in the list had problems, so return of zero means A-OK.
    //
    static hsBool ComputeRepMasks(int num, const int quals[], const int caps[], plLoadMask masks[]);
    static UInt32 ValidateReps(int num, const int quals[], const int caps[]);
    static UInt32 ValidateMasks(int num, plLoadMask masks[]);
};

#endif // plLoadMask_inc