author | unc0rr |
Wed, 01 Nov 2006 19:36:41 +0000 | |
changeset 227 | 4f6940084811 |
parent 183 | 57c2ef19f719 |
child 320 | 1ee7f087195a |
permissions | -rw-r--r-- |
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(* |
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* Hedgewars, a worms-like game |
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* Copyright (c) 2004-2006 Andrey Korotaev <unC0Rr@gmail.com> |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License as published by |
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* the Free Software Foundation; version 2 of the License |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the GNU General Public License |
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* along with this program; if not, write to the Free Software |
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA |
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*) |
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unit uRandom; |
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interface |
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{$INCLUDE options.inc} |
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procedure SetRandomSeed(Seed: shortstring); |
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function GetRandom: Double; overload; |
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function GetRandom(m: LongWord): LongWord; overload; |
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implementation |
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var cirbuf: array[0..63] of Longword; |
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n: byte = 54; |
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function GetNext: Longword; |
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begin |
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n:= (n + 1) and $3F; |
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cirbuf[n]:= |
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(cirbuf[(n + 40) and $3F] + {n - 24 mod 64} |
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cirbuf[(n + 9) and $3F]) {n - 55 mod 64} |
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and $7FFFFFFF; {mod 2^31} |
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Result:= cirbuf[n] |
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end; |
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procedure SetRandomSeed(Seed: shortstring); |
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var i: Longword; |
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begin |
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401f4ea24715
Engine can generate land preview and send it via IPC
unc0rr
parents:
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n:= 54; |
401f4ea24715
Engine can generate land preview and send it via IPC
unc0rr
parents:
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changeset
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if Length(Seed) > 54 then Seed:= copy(Seed, 1, 54); // not 55 to ensure we have odd numbers in cirbuf |
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for i:= 0 to pred(Length(Seed)) do |
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cirbuf[i]:= byte(Seed[i + 1]) * (i + 1); |
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for i:= Length(Seed) to 54 do |
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cirbuf[i]:= i * 7 + 1; |
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for i:= 0 to 1023 do GetNext |
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end; |
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function GetRandom: Double; |
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begin |
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Result:= frac( GetNext * 0.00073 + GetNext * 0.00301) |
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end; |
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function GetRandom(m: LongWord): LongWord; |
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begin |
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GetNext; |
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Result:= GetNext mod m |
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end; |
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end. |