1/**
2 * Copyright (c) 2006-2023 LOVE Development Team
3 *
4 * This software is provided 'as-is', without any express or implied
5 * warranty. In no event will the authors be held liable for any damages
6 * arising from the use of this software.
7 *
8 * Permission is granted to anyone to use this software for any purpose,
9 * including commercial applications, and to alter it and redistribute it
10 * freely, subject to the following restrictions:
11 *
12 * 1. The origin of this software must not be misrepresented; you must not
13 * claim that you wrote the original software. If you use this software
14 * in a product, an acknowledgment in the product documentation would be
15 * appreciated but is not required.
16 * 2. Altered source versions must be plainly marked as such, and must not be
17 * misrepresented as being the original software.
18 * 3. This notice may not be removed or altered from any source distribution.
19 **/
20
21#include "wrap_RandomGenerator.h"
22
23#include <cmath>
24#include <algorithm>
25
26// Put the Lua code directly into a raw string literal.
27static const char randomgenerator_lua[] =
28#include "wrap_RandomGenerator.lua"
29;
30
31namespace love
32{
33namespace math
34{
35
36template <typename T>
37static T checkrandomseed_part(lua_State *L, int idx)
38{
39 double num = luaL_checknumber(L, idx);
40 double inf = std::numeric_limits<double>::infinity();
41
42 // Disallow conversions from infinity and NaN.
43 if (num == inf || num == -inf || num != num)
44 luaL_argerror(L, idx, "invalid random seed");
45
46 return (T) num;
47}
48
49RandomGenerator::Seed luax_checkrandomseed(lua_State *L, int idx)
50{
51 RandomGenerator::Seed s;
52
53 if (!lua_isnoneornil(L, idx + 1))
54 {
55 s.b32.low = checkrandomseed_part<uint32>(L, idx);
56 s.b32.high = checkrandomseed_part<uint32>(L, idx + 1);
57 }
58 else
59 s.b64 = checkrandomseed_part<uint64>(L, idx);
60
61 return s;
62}
63
64RandomGenerator *luax_checkrandomgenerator(lua_State *L, int idx)
65{
66 return luax_checktype<RandomGenerator>(L, idx);
67}
68
69int w_RandomGenerator__random(lua_State *L)
70{
71 RandomGenerator *rng = luax_checkrandomgenerator(L, 1);
72 lua_pushnumber(L, rng->random());
73 return 1;
74}
75
76int w_RandomGenerator_randomNormal(lua_State *L)
77{
78 RandomGenerator *rng = luax_checkrandomgenerator(L, 1);
79
80 double stddev = luaL_optnumber(L, 2, 1.0);
81 double mean = luaL_optnumber(L, 3, 0.0);
82 double r = rng->randomNormal(stddev);
83
84 lua_pushnumber(L, r + mean);
85 return 1;
86}
87
88int w_RandomGenerator_setSeed(lua_State *L)
89{
90 RandomGenerator *rng = luax_checkrandomgenerator(L, 1);
91 luax_catchexcept(L, [&](){ rng->setSeed(luax_checkrandomseed(L, 2)); });
92 return 0;
93}
94
95int w_RandomGenerator_getSeed(lua_State *L)
96{
97 RandomGenerator *rng = luax_checkrandomgenerator(L, 1);
98 RandomGenerator::Seed s = rng->getSeed();
99 lua_pushnumber(L, (lua_Number) s.b32.low);
100 lua_pushnumber(L, (lua_Number) s.b32.high);
101 return 2;
102}
103
104int w_RandomGenerator_setState(lua_State *L)
105{
106 RandomGenerator *rng = luax_checkrandomgenerator(L, 1);
107 luax_catchexcept(L, [&](){ rng->setState(luax_checkstring(L, 2)); });
108 return 0;
109}
110
111int w_RandomGenerator_getState(lua_State *L)
112{
113 RandomGenerator *rng = luax_checkrandomgenerator(L, 1);
114 luax_pushstring(L, rng->getState());
115 return 1;
116}
117
118// C functions in a struct, necessary for the FFI versions of RandomGenerator functions.
119struct FFI_RandomGenerator
120{
121 double (*random)(Proxy *p);
122 double (*randomNormal)(Proxy *p, double stddev, double mean);
123};
124
125static FFI_RandomGenerator ffifuncs =
126{
127 [](Proxy *p) -> double // random()
128 {
129 auto rng = luax_ffi_checktype<RandomGenerator>(p);
130 return rng != nullptr ? rng->random() : 0.0;
131 },
132
133 [](Proxy *p, double stdddev, double mean) -> double // randomNormal
134 {
135 auto rng = luax_ffi_checktype<RandomGenerator>(p);
136 return rng != nullptr ? (rng->randomNormal(stdddev) + mean) : 0.0;
137 }
138};
139
140static const luaL_Reg w_RandomGenerator_functions[] =
141{
142 { "_random", w_RandomGenerator__random }, // random() is defined in wrap_RandomGenerator.lua.
143 { "randomNormal", w_RandomGenerator_randomNormal },
144 { "setSeed", w_RandomGenerator_setSeed },
145 { "getSeed", w_RandomGenerator_getSeed },
146 { "setState", w_RandomGenerator_setState },
147 { "getState", w_RandomGenerator_getState },
148 { 0, 0 }
149};
150
151extern "C" int luaopen_randomgenerator(lua_State *L)
152{
153 int n = luax_register_type(L, &RandomGenerator::type, w_RandomGenerator_functions, nullptr);
154
155 luax_runwrapper(L, randomgenerator_lua, sizeof(randomgenerator_lua), "RandomGenerator.lua", RandomGenerator::type, &ffifuncs);
156
157 return n;
158}
159
160} // math
161} // love
162