gzdoom/src/m_random.cpp

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// Emacs style mode select -*- C++ -*-
//-----------------------------------------------------------------------------
//
// $Id: m_random.c,v 1.6 1998/05/03 23:13:18 killough Exp $
//
// Copyright (C) 1993-1996 by id Software, Inc.
//
// This source is available for distribution and/or modification
// only under the terms of the DOOM Source Code License as
// published by id Software. All rights reserved.
//
// The source is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// FITNESS FOR A PARTICULAR PURPOSE. See the DOOM Source Code License
// for more details.
//
//
// DESCRIPTION:
// Random number LUT.
//
// 1/19/98 killough: Rewrote random number generator for better randomness,
// while at the same time maintaining demo sync and backward compatibility.
//
// 2/16/98 killough: Made each RNG local to each control-equivalent block,
// to reduce the chances of demo sync problems.
//
// [RH] Changed to use different class instances for different RNGs. Be
// sure to compile with _DEBUG if you want to catch bad RNG names.
//
//-----------------------------------------------------------------------------
#include <assert.h>
#include "doomstat.h"
#include "m_random.h"
#include "farchive.h"
#include "b_bot.h"
#include "m_png.h"
#include "m_crc32.h"
#include "i_system.h"
#include "c_dispatch.h"
#include "files.h"
#define RAND_ID MAKE_ID('r','a','N','d')
FRandom M_Random;
inline int UpdateSeed (DWORD &seed)
{
DWORD oldseed = seed;
seed = oldseed * 1664525ul + 221297ul;
return (int)oldseed;
}
DWORD rngseed = 1993; // killough 3/26/98: The seed
FRandom *FRandom::RNGList;
FRandom::FRandom ()
: Seed (0), Next (NULL), NameCRC (0)
{
#ifdef _DEBUG
Name = NULL;
#endif
Next = RNGList;
RNGList = this;
}
FRandom::FRandom (const char *name)
: Seed (0)
{
NameCRC = CalcCRC32 ((const BYTE *)name, (unsigned int)strlen (name));
#ifdef _DEBUG
Name = name;
// A CRC of 0 is reserved for nameless RNGs that don't get stored
// in savegames. The chance is very low that you would get a CRC of 0,
// but it's still possible.
assert (NameCRC != 0);
#endif
// Insert the RNG in the list, sorted by CRC
FRandom **prev = &RNGList, *probe = RNGList;
while (probe != NULL && probe->NameCRC < NameCRC)
{
prev = &probe->Next;
probe = probe->Next;
}
#ifdef _DEBUG
if (probe != NULL)
{
// Because RNGs are identified by their CRCs in save games,
// no two RNGs can have names that hash to the same CRC.
// Obviously, this means every RNG must have a unique name.
assert (probe->NameCRC != NameCRC);
}
#endif
Next = probe;
*prev = this;
}
FRandom::~FRandom ()
{
FRandom *rng, **prev;
FRandom *last = NULL;
prev = &RNGList;
rng = RNGList;
while (rng != NULL && rng != this)
{
last = rng;
rng = rng->Next;
}
if (rng != NULL)
{
*prev = rng->Next;
}
}
int FRandom::operator() ()
{
return (UpdateSeed (Seed) >> 20) & 255;
}
- Fixed compilation with mingw again. - Added multiple-choice sound sequences. These overcome one of the major deficiences of the Hexen-inherited SNDSEQ system while still being Hexen compatible: Custom door sounds can now use different opening and closing sequences, for both normal and blazing speeds. - Added a serializer for TArray. - Added a countof macro to doomtype.h. See the1's blog to find out why it's implemented the way it is. <http://blogs.msdn.com/the1/articles/210011.aspx> - Added a new method to FRandom for getting random numbers larger than 255, which lets me: - Fixed: SNDSEQ delayrand commands could delay for no more than 255 tics. - Fixed: If you're going to have sector_t.SoundTarget, then they need to be included in the pointer cleanup scans. - Ported back newer name code from 2.1. - Fixed: Using -warp with only one parameter in Doom and Heretic to select a map on episode 1 no longer worked. - New: Loading a multiplayer save now restores the players based on their names rather than on their connection order. Using connection order was sensible when -net was the only way to start a network game, but with -host/-join, it's not so nice. Also, if there aren't enough players in the save, then the extra players will be spawned normally, so you can continue a saved game with more players than you started it with. - Added some new SNDSEQ commands to make it possible to define Heretic's ambient sounds in SNDSEQ: volumerel, volumerand, slot, randomsequence, delayonce, and restart. With these, it is basically possible to obsolete all of the $ambient SNDINFO commands. - Fixed: Sound sequences would only execute one command each time they were ticked. - Fixed: No bounds checking was done on the volume sound sequences played at. - Fixed: The tic parameter to playloop was useless and caused it to act like a redundant playrepeat. I have removed all the logic that caused playloop to play repeating sounds, and now it acts like an infinite sequence of play/delay commands until the sequence is stopped. - Fixed: Sound sequences were ticked every frame, not every tic, so all the delay commands were timed incorrectly and varied depending on your framerate. Since this is useful for restarting looping sounds that got cut off, I have not changed this. Instead, the delay commands now record the tic when execution should resume, not the number of tics left to delay. SVN r57 (trunk)
2006-04-21 01:22:55 +00:00
int FRandom::operator() (int mod)
{
if (mod <= 256)
{ // The mod is small enough, so a byte is enough to get a good number.
return (*this)() % mod;
}
else
{ // For mods > 256, construct a 32-bit int and modulo that.
int num = (*this)();
num = (num << 8) | (*this)();
num = (num << 8) | (*this)();
num = (num << 8) | (*this)();
return (num&0x7fffffff) % mod;
- Fixed compilation with mingw again. - Added multiple-choice sound sequences. These overcome one of the major deficiences of the Hexen-inherited SNDSEQ system while still being Hexen compatible: Custom door sounds can now use different opening and closing sequences, for both normal and blazing speeds. - Added a serializer for TArray. - Added a countof macro to doomtype.h. See the1's blog to find out why it's implemented the way it is. <http://blogs.msdn.com/the1/articles/210011.aspx> - Added a new method to FRandom for getting random numbers larger than 255, which lets me: - Fixed: SNDSEQ delayrand commands could delay for no more than 255 tics. - Fixed: If you're going to have sector_t.SoundTarget, then they need to be included in the pointer cleanup scans. - Ported back newer name code from 2.1. - Fixed: Using -warp with only one parameter in Doom and Heretic to select a map on episode 1 no longer worked. - New: Loading a multiplayer save now restores the players based on their names rather than on their connection order. Using connection order was sensible when -net was the only way to start a network game, but with -host/-join, it's not so nice. Also, if there aren't enough players in the save, then the extra players will be spawned normally, so you can continue a saved game with more players than you started it with. - Added some new SNDSEQ commands to make it possible to define Heretic's ambient sounds in SNDSEQ: volumerel, volumerand, slot, randomsequence, delayonce, and restart. With these, it is basically possible to obsolete all of the $ambient SNDINFO commands. - Fixed: Sound sequences would only execute one command each time they were ticked. - Fixed: No bounds checking was done on the volume sound sequences played at. - Fixed: The tic parameter to playloop was useless and caused it to act like a redundant playrepeat. I have removed all the logic that caused playloop to play repeating sounds, and now it acts like an infinite sequence of play/delay commands until the sequence is stopped. - Fixed: Sound sequences were ticked every frame, not every tic, so all the delay commands were timed incorrectly and varied depending on your framerate. Since this is useful for restarting looping sounds that got cut off, I have not changed this. Instead, the delay commands now record the tic when execution should resume, not the number of tics left to delay. SVN r57 (trunk)
2006-04-21 01:22:55 +00:00
}
}
int FRandom::Random2 ()
{
- Fixed compilation with mingw again. - Added multiple-choice sound sequences. These overcome one of the major deficiences of the Hexen-inherited SNDSEQ system while still being Hexen compatible: Custom door sounds can now use different opening and closing sequences, for both normal and blazing speeds. - Added a serializer for TArray. - Added a countof macro to doomtype.h. See the1's blog to find out why it's implemented the way it is. <http://blogs.msdn.com/the1/articles/210011.aspx> - Added a new method to FRandom for getting random numbers larger than 255, which lets me: - Fixed: SNDSEQ delayrand commands could delay for no more than 255 tics. - Fixed: If you're going to have sector_t.SoundTarget, then they need to be included in the pointer cleanup scans. - Ported back newer name code from 2.1. - Fixed: Using -warp with only one parameter in Doom and Heretic to select a map on episode 1 no longer worked. - New: Loading a multiplayer save now restores the players based on their names rather than on their connection order. Using connection order was sensible when -net was the only way to start a network game, but with -host/-join, it's not so nice. Also, if there aren't enough players in the save, then the extra players will be spawned normally, so you can continue a saved game with more players than you started it with. - Added some new SNDSEQ commands to make it possible to define Heretic's ambient sounds in SNDSEQ: volumerel, volumerand, slot, randomsequence, delayonce, and restart. With these, it is basically possible to obsolete all of the $ambient SNDINFO commands. - Fixed: Sound sequences would only execute one command each time they were ticked. - Fixed: No bounds checking was done on the volume sound sequences played at. - Fixed: The tic parameter to playloop was useless and caused it to act like a redundant playrepeat. I have removed all the logic that caused playloop to play repeating sounds, and now it acts like an infinite sequence of play/delay commands until the sequence is stopped. - Fixed: Sound sequences were ticked every frame, not every tic, so all the delay commands were timed incorrectly and varied depending on your framerate. Since this is useful for restarting looping sounds that got cut off, I have not changed this. Instead, the delay commands now record the tic when execution should resume, not the number of tics left to delay. SVN r57 (trunk)
2006-04-21 01:22:55 +00:00
int t = (*this)();
int u = (*this)();
return t - u;
}
int FRandom::Random2 (int mask)
{
int t = (*this)() & mask;
int u = (*this)() & mask;
return t - u;
}
int FRandom::HitDice (int count)
{
return (1 + ((UpdateSeed (Seed) >> 20) & 7)) * count;
}
// Initialize all the seeds
//
// This initialization method is critical to maintaining demo sync.
// Each seed is initialized according to its class. killough
//
void FRandom::StaticClearRandom ()
{
const DWORD seed = rngseed*2+1; // add 3/26/98: add rngseed
FRandom *rng = FRandom::RNGList;
// go through each RNG and set each starting seed differently
while (rng != NULL)
{
// [RH] Use the RNG's name's CRC to modify the original seed.
// This way, new RNGs can be added later, and it doesn't matter
// which order they get initialized in.
rng->Seed = seed * rng->NameCRC;
rng = rng->Next;
}
}
// This function produces a DWORD that can be used to check the consistancy
// of network games between different machines. Only a select few RNGs are
// used for the sum, because not all RNGs are important to network sync.
extern FRandom pr_spawnmobj;
extern FRandom pr_acs;
extern FRandom pr_chase;
extern FRandom pr_lost;
extern FRandom pr_slam;
DWORD FRandom::StaticSumSeeds ()
{
return pr_spawnmobj.Seed + pr_acs.Seed + pr_chase.Seed + pr_lost.Seed + pr_slam.Seed;
}
void FRandom::StaticWriteRNGState (FILE *file)
{
FRandom *rng;
const DWORD seed = rngseed*2+1;
FPNGChunkArchive arc (file, RAND_ID);
arc << rngseed;
// Only write those RNGs that have been used
for (rng = FRandom::RNGList; rng != NULL; rng = rng->Next)
{
if (rng->NameCRC != 0 && rng->Seed != seed + rng->NameCRC)
{
arc << rng->NameCRC << rng->Seed;
}
}
}
void FRandom::StaticReadRNGState (PNGHandle *png)
{
FRandom *rng;
size_t len = M_FindPNGChunk (png, RAND_ID);
if (len != 0)
{
const int rngcount = (int)((len-4) / 8);
int i;
DWORD crc;
FPNGChunkArchive arc (png->File->GetFile(), RAND_ID, len);
arc << rngseed;
FRandom::StaticClearRandom ();
for (i = rngcount; i; --i)
{
arc << crc;
for (rng = FRandom::RNGList; rng != NULL; rng = rng->Next)
{
if (rng->NameCRC == crc)
{
arc << rng->Seed;
break;
}
}
}
png->File->ResetFilePtr();
}
}
// This function attempts to find an RNG with the given name.
// If it can't it will create a new one. Duplicate CRCs will
// be ignored and if it happens map to the same RNG.
// This is for use by DECORATE.
extern FRandom pr_exrandom;
class NewRNGList : public TArray<FRandom*>
{
public:
~NewRNGList()
{
for(unsigned i=0;i<Size();i++)
{
delete (*this)[i];
}
}
};
static NewRNGList NewRNGs;
FRandom *FRandom::StaticFindRNG (const char *name)
{
DWORD NameCRC = CalcCRC32 ((const BYTE *)name, (unsigned int)strlen (name));
// Use the default RNG if this one happens to have a CRC of 0.
if (NameCRC==0) return &pr_exrandom;
// Find the RNG in the list, sorted by CRC
FRandom **prev = &RNGList, *probe = RNGList;
while (probe != NULL && probe->NameCRC < NameCRC)
{
prev = &probe->Next;
probe = probe->Next;
}
// Found one so return it.
if (probe == NULL || probe->NameCRC != NameCRC)
{
// A matching RNG doesn't exist yet so create it.
probe = new FRandom(name);
// Store the new RNG for destruction when ZDoom quits.
NewRNGs.Push(probe);
}
return probe;
}
#ifdef _DEBUG
void FRandom::StaticPrintSeeds ()
{
FRandom *rng = RNGList;
while (rng != NULL)
{
Printf ("%s: %08x\n", rng->Name, rng->Seed);
rng = rng->Next;
}
}
CCMD (showrngs)
{
FRandom::StaticPrintSeeds ();
}
#endif