diff -r 475c0f2f9d17 -r 30f2d1037d5d hedgewars/uRandom.pas --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/hedgewars/uRandom.pas Mon Aug 22 13:35:41 2005 +0000 @@ -0,0 +1,75 @@ +(* + * Hedgewars, a worms-like game + * Copyright (c) 2004, 2005 Andrey Korotaev + * + * Distributed under the terms of the BSD-modified licence: + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * with the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or + * sell copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO + * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; + * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR + * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + *) + +unit uRandom; +interface +uses uSHA; + +procedure SetRandomParams(Seed: shortstring; FillBuf: shortstring); +function GetRandom: real; overload; +function GetRandom(m: LongWord): LongWord; overload; + +implementation +var sc1, sc2: TSHA1Context; + Fill: shortstring; + +procedure SetRandomParams(Seed: shortstring; FillBuf: shortstring); +begin +SHA1Init(sc1); +SHA1Update(sc1, @Seed, Length(Seed)+1); +Fill:= FillBuf +end; + +function GetRandom: real; +var dig: TSHA1Digest; +begin +SHA1Update(sc1, @Fill[1], Length(Fill)); +sc2:= sc1; +dig:= SHA1Final(sc1); +Result:= frac( dig.LongWords[0]*0.0000731563977 + + pi * dig.Words[6] + + 0.0109070019*dig.Words[9]); +sc1:= sc2 +end; + +function GetRandom(m: LongWord): LongWord; +var dig: TSHA1Digest; +begin +SHA1Update(sc1, @Fill[1], Length(Fill)); +sc2:= sc1; +dig:= SHA1Final(sc1); +Result:= (((dig.LongWords[0] mod m) + (dig.LongWords[2] mod m)) mod m + (dig.LongWords[3] mod m)) mod m; +sc1:= sc2 +end; + +end.