Miguel Ruiz / SDL_lib2

SDL Library

Dependents:   H261_decoder

SDL_test_random.h@0:7fb6877b5d7c, 2016-09-22 (annotated)

Committer:
miruga27
Date:
Thu Sep 22 00:03:09 2016 +0000
Revision:
0:7fb6877b5d7c
SDL

Who changed what in which revision?

UserRevisionLine numberNew contents of line
miruga27 0:7fb6877b5d7c 1 /*
miruga27 0:7fb6877b5d7c 2 Simple DirectMedia Layer
miruga27 0:7fb6877b5d7c 3 Copyright (C) 1997-2014 Sam Lantinga <slouken@libsdl.org>
miruga27 0:7fb6877b5d7c 4
miruga27 0:7fb6877b5d7c 5 This software is provided 'as-is', without any express or implied
miruga27 0:7fb6877b5d7c 6 warranty. In no event will the authors be held liable for any damages
miruga27 0:7fb6877b5d7c 7 arising from the use of this software.
miruga27 0:7fb6877b5d7c 8
miruga27 0:7fb6877b5d7c 9 Permission is granted to anyone to use this software for any purpose,
miruga27 0:7fb6877b5d7c 10 including commercial applications, and to alter it and redistribute it
miruga27 0:7fb6877b5d7c 11 freely, subject to the following restrictions:
miruga27 0:7fb6877b5d7c 12
miruga27 0:7fb6877b5d7c 13 1. The origin of this software must not be misrepresented; you must not
miruga27 0:7fb6877b5d7c 14 claim that you wrote the original software. If you use this software
miruga27 0:7fb6877b5d7c 15 in a product, an acknowledgment in the product documentation would be
miruga27 0:7fb6877b5d7c 16 appreciated but is not required.
miruga27 0:7fb6877b5d7c 17 2. Altered source versions must be plainly marked as such, and must not be
miruga27 0:7fb6877b5d7c 18 misrepresented as being the original software.
miruga27 0:7fb6877b5d7c 19 3. This notice may not be removed or altered from any source distribution.
miruga27 0:7fb6877b5d7c 20 */
miruga27 0:7fb6877b5d7c 21
miruga27 0:7fb6877b5d7c 22 /**
miruga27 0:7fb6877b5d7c 23 * \file SDL_test_random.h
miruga27 0:7fb6877b5d7c 24 *
miruga27 0:7fb6877b5d7c 25 * Include file for SDL test framework.
miruga27 0:7fb6877b5d7c 26 *
miruga27 0:7fb6877b5d7c 27 * This code is a part of the SDL2_test library, not the main SDL library.
miruga27 0:7fb6877b5d7c 28 */
miruga27 0:7fb6877b5d7c 29
miruga27 0:7fb6877b5d7c 30 /*
miruga27 0:7fb6877b5d7c 31
miruga27 0:7fb6877b5d7c 32 A "32-bit Multiply with carry random number generator. Very fast.
miruga27 0:7fb6877b5d7c 33 Includes a list of recommended multipliers.
miruga27 0:7fb6877b5d7c 34
miruga27 0:7fb6877b5d7c 35 multiply-with-carry generator: x(n) = a*x(n-1) + carry mod 2^32.
miruga27 0:7fb6877b5d7c 36 period: (a*2^31)-1
miruga27 0:7fb6877b5d7c 37
miruga27 0:7fb6877b5d7c 38 */
miruga27 0:7fb6877b5d7c 39
miruga27 0:7fb6877b5d7c 40 #ifndef _SDL_test_random_h
miruga27 0:7fb6877b5d7c 41 #define _SDL_test_random_h
miruga27 0:7fb6877b5d7c 42
miruga27 0:7fb6877b5d7c 43 #include "begin_code.h"
miruga27 0:7fb6877b5d7c 44 /* Set up for C function definitions, even when using C++ */
miruga27 0:7fb6877b5d7c 45 #ifdef __cplusplus
miruga27 0:7fb6877b5d7c 46 extern "C" {
miruga27 0:7fb6877b5d7c 47 #endif
miruga27 0:7fb6877b5d7c 48
miruga27 0:7fb6877b5d7c 49 /* --- Definitions */
miruga27 0:7fb6877b5d7c 50
miruga27 0:7fb6877b5d7c 51 /*
miruga27 0:7fb6877b5d7c 52 * Macros that return a random number in a specific format.
miruga27 0:7fb6877b5d7c 53 */
miruga27 0:7fb6877b5d7c 54 #define SDLTest_RandomInt(c) ((int)SDLTest_Random(c))
miruga27 0:7fb6877b5d7c 55
miruga27 0:7fb6877b5d7c 56 /*
miruga27 0:7fb6877b5d7c 57 * Context structure for the random number generator state.
miruga27 0:7fb6877b5d7c 58 */
miruga27 0:7fb6877b5d7c 59 typedef struct {
miruga27 0:7fb6877b5d7c 60 unsigned int a;
miruga27 0:7fb6877b5d7c 61 unsigned int x;
miruga27 0:7fb6877b5d7c 62 unsigned int c;
miruga27 0:7fb6877b5d7c 63 unsigned int ah;
miruga27 0:7fb6877b5d7c 64 unsigned int al;
miruga27 0:7fb6877b5d7c 65 } SDLTest_RandomContext;
miruga27 0:7fb6877b5d7c 66
miruga27 0:7fb6877b5d7c 67
miruga27 0:7fb6877b5d7c 68 /* --- Function prototypes */
miruga27 0:7fb6877b5d7c 69
miruga27 0:7fb6877b5d7c 70 /**
miruga27 0:7fb6877b5d7c 71 * \brief Initialize random number generator with two integers.
miruga27 0:7fb6877b5d7c 72 *
miruga27 0:7fb6877b5d7c 73 * Note: The random sequence of numbers returned by ...Random() is the
miruga27 0:7fb6877b5d7c 74 * same for the same two integers and has a period of 2^31.
miruga27 0:7fb6877b5d7c 75 *
miruga27 0:7fb6877b5d7c 76 * \param rndContext pointer to context structure
miruga27 0:7fb6877b5d7c 77 * \param xi integer that defines the random sequence
miruga27 0:7fb6877b5d7c 78 * \param ci integer that defines the random sequence
miruga27 0:7fb6877b5d7c 79 *
miruga27 0:7fb6877b5d7c 80 */
miruga27 0:7fb6877b5d7c 81 void SDLTest_RandomInit(SDLTest_RandomContext * rndContext, unsigned int xi,
miruga27 0:7fb6877b5d7c 82 unsigned int ci);
miruga27 0:7fb6877b5d7c 83
miruga27 0:7fb6877b5d7c 84 /**
miruga27 0:7fb6877b5d7c 85 * \brief Initialize random number generator based on current system time.
miruga27 0:7fb6877b5d7c 86 *
miruga27 0:7fb6877b5d7c 87 * \param rndContext pointer to context structure
miruga27 0:7fb6877b5d7c 88 *
miruga27 0:7fb6877b5d7c 89 */
miruga27 0:7fb6877b5d7c 90 void SDLTest_RandomInitTime(SDLTest_RandomContext *rndContext);
miruga27 0:7fb6877b5d7c 91
miruga27 0:7fb6877b5d7c 92
miruga27 0:7fb6877b5d7c 93 /**
miruga27 0:7fb6877b5d7c 94 * \brief Initialize random number generator based on current system time.
miruga27 0:7fb6877b5d7c 95 *
miruga27 0:7fb6877b5d7c 96 * Note: ...RandomInit() or ...RandomInitTime() must have been called
miruga27 0:7fb6877b5d7c 97 * before using this function.
miruga27 0:7fb6877b5d7c 98 *
miruga27 0:7fb6877b5d7c 99 * \param rndContext pointer to context structure
miruga27 0:7fb6877b5d7c 100 *
miruga27 0:7fb6877b5d7c 101 * \returns A random number (32bit unsigned integer)
miruga27 0:7fb6877b5d7c 102 *
miruga27 0:7fb6877b5d7c 103 */
miruga27 0:7fb6877b5d7c 104 unsigned int SDLTest_Random(SDLTest_RandomContext *rndContext);
miruga27 0:7fb6877b5d7c 105
miruga27 0:7fb6877b5d7c 106
miruga27 0:7fb6877b5d7c 107 /* Ends C function definitions when using C++ */
miruga27 0:7fb6877b5d7c 108 #ifdef __cplusplus
miruga27 0:7fb6877b5d7c 109 }
miruga27 0:7fb6877b5d7c 110 #endif
miruga27 0:7fb6877b5d7c 111 #include "close_code.h"
miruga27 0:7fb6877b5d7c 112
miruga27 0:7fb6877b5d7c 113 #endif /* _SDL_test_random_h */
miruga27 0:7fb6877b5d7c 114
miruga27 0:7fb6877b5d7c 115 /* vi: set ts=4 sw=4 expandtab: */