Implemented LuaJIT FFI versions of love.math.random and RandomGenerator:random.

platform/xcode/liblove.xcodeproj/project.pbxproj

@@ -840,6 +840,7 @@
 		FA27B3C61B4985D8008A9DCE /* Video.cpp in Sources */ = {isa = PBXBuildFile; fileRef = FA27B3C31B4985D8008A9DCE /* Video.cpp */; };
 		FA27B3C71B4985D8008A9DCE /* Video.h in Headers */ = {isa = PBXBuildFile; fileRef = FA27B3C41B4985D8008A9DCE /* Video.h */; };
 		FA27B3C91B498623008A9DCE /* Theora.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = FA27B3C81B498623008A9DCE /* Theora.framework */; };
+		FA2E9BFF1C19E00C0004A1EE /* wrap_RandomGenerator.lua in Resources */ = {isa = PBXBuildFile; fileRef = FA2E9BFE1C19E00C0004A1EE /* wrap_RandomGenerator.lua */; };
 		FA317EBA18F28B6D00B0BCD7 /* libz.dylib in Frameworks */ = {isa = PBXBuildFile; fileRef = FA317EB918F28B6D00B0BCD7 /* libz.dylib */; };
 		FA41A3C81C0A1F950084430C /* ASTCHandler.cpp in Sources */ = {isa = PBXBuildFile; fileRef = FA41A3C61C0A1F950084430C /* ASTCHandler.cpp */; };
 		FA41A3C91C0A1F950084430C /* ASTCHandler.cpp in Sources */ = {isa = PBXBuildFile; fileRef = FA41A3C61C0A1F950084430C /* ASTCHandler.cpp */; };
@@ -1519,6 +1520,7 @@
 		FA27B3C81B498623008A9DCE /* Theora.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Theora.framework; path = /Library/Frameworks/Theora.framework; sourceTree = "<absolute>"; };
 		FA283EDC1B27CFAA00C70067 /* nogame.lua */ = {isa = PBXFileReference; lastKnownFileType = text; path = nogame.lua; sourceTree = "<group>"; };
 		FA283EDD1B27CFAA00C70067 /* nogame.lua.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = nogame.lua.h; sourceTree = "<group>"; };
+		FA2E9BFE1C19E00C0004A1EE /* wrap_RandomGenerator.lua */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = wrap_RandomGenerator.lua; sourceTree = "<group>"; };
 		FA317EB918F28B6D00B0BCD7 /* libz.dylib */ = {isa = PBXFileReference; lastKnownFileType = "compiled.mach-o.dylib"; name = libz.dylib; path = usr/lib/libz.dylib; sourceTree = SDKROOT; };
 		FA41A3C61C0A1F950084430C /* ASTCHandler.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = ASTCHandler.cpp; sourceTree = "<group>"; };
 		FA41A3C71C0A1F950084430C /* ASTCHandler.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASTCHandler.h; sourceTree = "<group>"; };
@@ -2461,6 +2463,7 @@
 				FA7DA04C1C16874A0056B200 /* wrap_Math.lua */,
 				FA0B7C0B1A95902C000E1D17 /* wrap_RandomGenerator.cpp */,
 				FA0B7C0C1A95902C000E1D17 /* wrap_RandomGenerator.h */,
+				FA2E9BFE1C19E00C0004A1EE /* wrap_RandomGenerator.lua */,
 			);
 			path = math;
 			sourceTree = "<group>";
@@ -3297,6 +3300,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				FA19C4C81B4B0BD50059B0B3 /* wrap_Video.lua in Resources */,
+				FA2E9BFF1C19E00C0004A1EE /* wrap_RandomGenerator.lua in Resources */,
 				FA7DA04D1C16874A0056B200 /* wrap_Math.lua in Resources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

src/modules/math/wrap_Math.cpp

@@ -39,9 +39,10 @@ namespace love
 namespace math
 {
 
-int w_random(lua_State *L)
+int w__random(lua_State *L)
 {
-	return luax_getrandom(L, 1, Math::instance.random());
+	lua_pushnumber(L, Math::instance.random());
+	return 1;
 }
 
 int w_randomNormal(lua_State *L)
@@ -422,6 +423,8 @@ int w_decompress(lua_State *L)
 // C functions in a struct, necessary for the FFI versions of math functions.
 struct FFI_Math
 {
+	double (*random)(void);
+
 	float (*noise1)(float x);
 	float (*noise2)(float x, float y);
 	float (*noise3)(float x, float y, float z);
@@ -433,6 +436,11 @@ struct FFI_Math
 
 static FFI_Math ffifuncs =
 {
+	[](void) -> double // random
+	{
+		return Math::instance.random();
+	},
+
 	[](float x) -> float // noise1
 	{
 		return Math::instance.noise(x);
@@ -463,7 +471,7 @@ static FFI_Math ffifuncs =
 // List of functions to wrap.
 static const luaL_Reg functions[] =
 {
-	{ "random", w_random },
+	{ "_random", w__random }, // love.math.random is inside wrap_Math.lua.
 	{ "randomNormal", w_randomNormal },
 	{ "setRandomSeed", w_setRandomSeed },
 	{ "getRandomSeed", w_getRandomSeed },

src/modules/math/wrap_Math.lua

@@ -22,7 +22,30 @@ misrepresented as being the original software.
 3. This notice may not be removed or altered from any source distribution.
 --]]
 
-local math, ffifuncspointer = ...
+local love_math, ffifuncspointer = ...
+
+local type, tonumber, error = type, tonumber, error
+local floor = math.floor
+
+local _random = love_math._random
+
+local function getrandom(r, l, u)
+	if u ~= nil then
+		if type(r) ~= "number" then error("bad argument #1 to 'random' (number expected)", 2) end
+		if type(l) ~= "number" then error("bad argument #2 to 'random' (number expected)", 2) end
+		return floor(r * (u - l + 1)) + l
+	elseif l ~= nil then
+		if type(l) ~= "number" then error("bad argument #1 to 'random' (number expected)", 2) end
+		return floor(r * l) + 1
+	else
+		return r
+	end
+end
+
+function love_math.random(l, u)
+	local r = _random()
+	return getrandom(r, l, u)
+end
 
 if type(jit) ~= "table" or not jit.status() then
 	-- LuaJIT's FFI is *much* slower than LOVE's regular methods when the JIT
@@ -33,12 +56,12 @@ end
 local status, ffi = pcall(require, "ffi")
 if not status then return end
 
-local type, tonumber = type, tonumber
-
 -- Matches the struct declaration in wrap_Math.cpp.
 pcall(ffi.cdef, [[
 typedef struct FFI_Math
 {
+	double (*random)(void);
+
 	float (*noise1)(float x);
 	float (*noise2)(float x, float y);
 	float (*noise3)(float x, float y, float z);
@@ -54,7 +77,12 @@ local ffifuncs = ffi.cast("FFI_Math *", ffifuncspointer)
 
 -- Overwrite some regular love.math functions with FFI implementations.
 
-function math.noise(x, y, z, w)
+function love_math.random(l, u)
+	local r = tonumber(ffifuncs.random())
+	return getrandom(r, l, u)
+end
+
+function love_math.noise(x, y, z, w)
 	if w ~= nil then
 		return tonumber(ffifuncs.noise4(x, y, z, w))
 	elseif z ~= nil then
@@ -73,7 +101,7 @@ local function gammaToLinear(c)
 	return c
 end
 
-function math.gammaToLinear(r, g, b, a)
+function love_math.gammaToLinear(r, g, b, a)
 	if type(r) == "table" then
 		local t = r
 		return gammaToLinear(t[1]), gammaToLinear(t[2]), gammaToLinear(t[3]), t[4]
@@ -88,7 +116,7 @@ local function linearToGamma(c)
 	return c
 end
 
-function math.linearToGamma(r, g, b, a)
+function love_math.linearToGamma(r, g, b, a)
 	if type(r) == "table" then
 		local t = r
 		return linearToGamma(t[1]), linearToGamma(t[2]), linearToGamma(t[3]), t[4]

src/modules/math/wrap_RandomGenerator.cpp

@@ -23,6 +23,11 @@
 #include <cmath>
 #include <algorithm>
 
+// Put the Lua code directly into a raw string literal.
+static const char randomgenerator_lua[] =
+#include "wrap_RandomGenerator.lua"
+;
+
 namespace love
 {
 namespace math
@@ -56,41 +61,16 @@ RandomGenerator::Seed luax_checkrandomseed(lua_State *L, int idx)
 	return s;
 }
 
-int luax_getrandom(lua_State *L, int startidx, double r)
-{
-	int l, u;
-	// from lua 5.1.4 source code: lmathlib.c:185 ff.
-	switch (lua_gettop(L) - (startidx - 1))
-	{
-	case 0:
-		lua_pushnumber(L, r);
-		break;
-	case 1:
-		u = (int) luaL_checknumber(L, startidx);
-		luaL_argcheck(L, 1 <= u, startidx, "interval is empty");
-		lua_pushnumber(L, floor(r * u) + 1);
-		break;
-	case 2:
-		l = (int) luaL_checknumber(L, startidx);
-		u = (int) luaL_checknumber(L, startidx + 1);
-		luaL_argcheck(L, l <= u, startidx + 1, "interval is empty");
-		lua_pushnumber(L, floor(r * (u - l + 1)) + l);
-		break;
-	default:
-		return luaL_error(L, "wrong number of arguments");
-	}
-	return 1;
-}
-
 RandomGenerator *luax_checkrandomgenerator(lua_State *L, int idx)
 {
 	return luax_checktype<RandomGenerator>(L, idx, MATH_RANDOM_GENERATOR_ID);
 }
 
-int w_RandomGenerator_random(lua_State *L)
+int w_RandomGenerator__random(lua_State *L)
 {
 	RandomGenerator *rng = luax_checkrandomgenerator(L, 1);
-	return luax_getrandom(L, 2, rng->random());
+	lua_pushnumber(L, rng->random());
+	return 1;
 }
 
 int w_RandomGenerator_randomNormal(lua_State *L)
@@ -135,9 +115,28 @@ int w_RandomGenerator_getState(lua_State *L)
 	return 1;
 }
 
+// C functions in a struct, necessary for the FFI versions of RandomGenerator functions.
+struct FFI_RandomGenerator
+{
+	double (*random)(Proxy *p);
+};
+
+static FFI_RandomGenerator ffifuncs =
+{
+	[](Proxy *p) -> double // random()
+	{
+		// FIXME: We need better type-checking...
+		if (!typeFlags[p->type][MATH_RANDOM_GENERATOR_ID])
+			return 0.0;
+
+		RandomGenerator *rng = (RandomGenerator *) p->object;
+		return rng->random();
+	}
+};
+
 static const luaL_Reg w_RandomGenerator_functions[] =
 {
-	{ "random", w_RandomGenerator_random },
+	{ "_random", w_RandomGenerator__random }, // random() is defined in wrap_RandomGenerator.lua.
 	{ "randomNormal", w_RandomGenerator_randomNormal },
 	{ "setSeed", w_RandomGenerator_setSeed },
 	{ "getSeed", w_RandomGenerator_getSeed },
@@ -148,7 +147,24 @@ static const luaL_Reg w_RandomGenerator_functions[] =
 
 extern "C" int luaopen_randomgenerator(lua_State *L)
 {
-	return luax_register_type(L, MATH_RANDOM_GENERATOR_ID, "RandomGenerator", w_RandomGenerator_functions, nullptr);
+	int n = luax_register_type(L, MATH_RANDOM_GENERATOR_ID, "RandomGenerator", w_RandomGenerator_functions, nullptr);
+
+	luax_gettypemetatable(L, MATH_RANDOM_GENERATOR_ID);
+
+	// Load and execute wrap_RandomGenerator.lua, sending the metatable and the
+	// ffi functions struct pointer as arguments.
+	if (lua_istable(L, -1))
+	{
+		luaL_loadbuffer(L, randomgenerator_lua, sizeof(randomgenerator_lua), "wrap_RandomGenerator.lua");
+		lua_pushvalue(L, -2);
+		lua_pushlightuserdata(L, &ffifuncs);
+		lua_call(L, 2, 0);
+	}
+
+	// Pop the metatable.
+	lua_pop(L, 1);
+
+	return n;
 }
 
 } // math

src/modules/math/wrap_RandomGenerator.h

@@ -33,7 +33,6 @@ namespace math
 
 // Helper functions.
 RandomGenerator::Seed luax_checkrandomseed(lua_State *L, int idx);
-int luax_getrandom(lua_State *L, int startidx, double r);
 
 RandomGenerator *luax_checkrandomgenerator(lua_State *L, int idx);
 extern "C" int luaopen_randomgenerator(lua_State *L);

src/modules/math/wrap_RandomGenerator.lua

@@ -0,0 +1,80 @@
+R"luastring"--(
+-- DO NOT REMOVE THE ABOVE LINE. It is used to load this file as a C++ string.
+-- There is a matching delimiter at the bottom of the file.
+
+--[[
+Copyright (c) 2006-2015 LOVE Development Team
+
+This software is provided 'as-is', without any express or implied
+warranty.  In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not
+claim that you wrote the original software. If you use this software
+in a product, an acknowledgment in the product documentation would be
+appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be
+misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+--]]
+
+local RandomGenerator_mt, ffifuncspointer = ...
+local RandomGenerator = RandomGenerator_mt.__index
+
+local type, tonumber, error = type, tonumber, error
+local floor = math.floor
+
+local _random = RandomGenerator._random
+
+local function getrandom(r, l, u)
+	if u ~= nil then
+		if type(r) ~= "number" then error("bad argument #1 to 'random' (number expected)", 2) end
+		if type(l) ~= "number" then error("bad argument #2 to 'random' (number expected)", 2) end
+		return floor(r * (u - l + 1)) + l
+	elseif l ~= nil then
+		if type(l) ~= "number" then error("bad argument #1 to 'random' (number expected)", 2) end
+		return floor(r * l) + 1
+	else
+		return r
+	end
+end
+
+function RandomGenerator:random(l, u)
+	local r = _random(self)
+	return getrandom(r, l, u)
+end
+
+if type(jit) ~= "table" or not jit.status() then
+	-- LuaJIT's FFI is *much* slower than LOVE's regular methods when the JIT
+	-- compiler is disabled.
+	return
+end
+
+local status, ffi = pcall(require, "ffi")
+if not status then return end
+
+pcall(ffi.cdef, [[
+typedef struct Proxy Proxy;
+
+typedef struct FFI_RandomGenerator
+{
+	double (*random)(Proxy *p);
+} FFI_RandomGenerator;
+]])
+
+local ffifuncs = ffi.cast("FFI_RandomGenerator *", ffifuncspointer)
+
+
+-- Overwrite some regular love.math functions with FFI implementations.
+
+function RandomGenerator:random(l, u)
+	local r = tonumber(ffifuncs.random(self))
+	return getrandom(r, l, u)
+end
+
+-- DO NOT REMOVE THE NEXT LINE. It is used to load this file as a C++ string.
+--)luastring"--"