diff options
Diffstat (limited to 'builtin/common/vector.lua')
-rw-r--r-- | builtin/common/vector.lua | 250 |
1 files changed, 185 insertions, 65 deletions
diff --git a/builtin/common/vector.lua b/builtin/common/vector.lua index d6437deda..581d014e0 100644 --- a/builtin/common/vector.lua +++ b/builtin/common/vector.lua @@ -1,73 +1,126 @@ +--[[ +Vector helpers +Note: The vector.*-functions must be able to accept old vectors that had no metatables +]] + +-- localize functions +local setmetatable = setmetatable vector = {} +local metatable = {} +vector.metatable = metatable + +local xyz = {"x", "y", "z"} + +-- only called when rawget(v, key) returns nil +function metatable.__index(v, key) + return rawget(v, xyz[key]) or vector[key] +end + +-- only called when rawget(v, key) returns nil +function metatable.__newindex(v, key, value) + rawset(v, xyz[key] or key, value) +end + +-- constructors + +local function fast_new(x, y, z) + return setmetatable({x = x, y = y, z = z}, metatable) +end + function vector.new(a, b, c) + if a and b and c then + return fast_new(a, b, c) + end + + -- deprecated, use vector.copy and vector.zero directly if type(a) == "table" then - assert(a.x and a.y and a.z, "Invalid vector passed to vector.new()") - return {x=a.x, y=a.y, z=a.z} - elseif a then - assert(b and c, "Invalid arguments for vector.new()") - return {x=a, y=b, z=c} + return vector.copy(a) + else + assert(not a, "Invalid arguments for vector.new()") + return vector.zero() + end +end + +function vector.zero() + return fast_new(0, 0, 0) +end + +function vector.copy(v) + assert(v.x and v.y and v.z, "Invalid vector passed to vector.copy()") + return fast_new(v.x, v.y, v.z) +end + +function vector.from_string(s, init) + local x, y, z, np = string.match(s, "^%s*%(%s*([^%s,]+)%s*[,%s]%s*([^%s,]+)%s*[,%s]" .. + "%s*([^%s,]+)%s*[,%s]?%s*%)()", init) + x = tonumber(x) + y = tonumber(y) + z = tonumber(z) + if not (x and y and z) then + return nil end - return {x=0, y=0, z=0} + return fast_new(x, y, z), np +end + +function vector.to_string(v) + return string.format("(%g, %g, %g)", v.x, v.y, v.z) end +metatable.__tostring = vector.to_string function vector.equals(a, b) return a.x == b.x and a.y == b.y and a.z == b.z end +metatable.__eq = vector.equals + +-- unary operations function vector.length(v) - return math.hypot(v.x, math.hypot(v.y, v.z)) + return math.sqrt(v.x * v.x + v.y * v.y + v.z * v.z) end +-- Note: we can not use __len because it is already used for primitive table length function vector.normalize(v) local len = vector.length(v) if len == 0 then - return {x=0, y=0, z=0} + return fast_new(0, 0, 0) else return vector.divide(v, len) end end function vector.floor(v) - return { - x = math.floor(v.x), - y = math.floor(v.y), - z = math.floor(v.z) - } + return vector.apply(v, math.floor) end function vector.round(v) - return { - x = math.floor(v.x + 0.5), - y = math.floor(v.y + 0.5), - z = math.floor(v.z + 0.5) - } + return fast_new( + math.round(v.x), + math.round(v.y), + math.round(v.z) + ) end function vector.apply(v, func) - return { - x = func(v.x), - y = func(v.y), - z = func(v.z) - } + return fast_new( + func(v.x), + func(v.y), + func(v.z) + ) end function vector.distance(a, b) local x = a.x - b.x local y = a.y - b.y local z = a.z - b.z - return math.hypot(x, math.hypot(y, z)) + return math.sqrt(x * x + y * y + z * z) end function vector.direction(pos1, pos2) - return vector.normalize({ - x = pos2.x - pos1.x, - y = pos2.y - pos1.y, - z = pos2.z - pos1.z - }) + return vector.subtract(pos2, pos1):normalize() end function vector.angle(a, b) @@ -82,70 +135,137 @@ function vector.dot(a, b) end function vector.cross(a, b) - return { - x = a.y * b.z - a.z * b.y, - y = a.z * b.x - a.x * b.z, - z = a.x * b.y - a.y * b.x - } + return fast_new( + a.y * b.z - a.z * b.y, + a.z * b.x - a.x * b.z, + a.x * b.y - a.y * b.x + ) end +function metatable.__unm(v) + return fast_new(-v.x, -v.y, -v.z) +end + +-- add, sub, mul, div operations + function vector.add(a, b) if type(b) == "table" then - return {x = a.x + b.x, - y = a.y + b.y, - z = a.z + b.z} + return fast_new( + a.x + b.x, + a.y + b.y, + a.z + b.z + ) else - return {x = a.x + b, - y = a.y + b, - z = a.z + b} + return fast_new( + a.x + b, + a.y + b, + a.z + b + ) end end +function metatable.__add(a, b) + return fast_new( + a.x + b.x, + a.y + b.y, + a.z + b.z + ) +end function vector.subtract(a, b) if type(b) == "table" then - return {x = a.x - b.x, - y = a.y - b.y, - z = a.z - b.z} + return fast_new( + a.x - b.x, + a.y - b.y, + a.z - b.z + ) else - return {x = a.x - b, - y = a.y - b, - z = a.z - b} + return fast_new( + a.x - b, + a.y - b, + a.z - b + ) end end +function metatable.__sub(a, b) + return fast_new( + a.x - b.x, + a.y - b.y, + a.z - b.z + ) +end function vector.multiply(a, b) if type(b) == "table" then - return {x = a.x * b.x, - y = a.y * b.y, - z = a.z * b.z} + return fast_new( + a.x * b.x, + a.y * b.y, + a.z * b.z + ) + else + return fast_new( + a.x * b, + a.y * b, + a.z * b + ) + end +end +function metatable.__mul(a, b) + if type(a) == "table" then + return fast_new( + a.x * b, + a.y * b, + a.z * b + ) else - return {x = a.x * b, - y = a.y * b, - z = a.z * b} + return fast_new( + a * b.x, + a * b.y, + a * b.z + ) end end function vector.divide(a, b) if type(b) == "table" then - return {x = a.x / b.x, - y = a.y / b.y, - z = a.z / b.z} + return fast_new( + a.x / b.x, + a.y / b.y, + a.z / b.z + ) else - return {x = a.x / b, - y = a.y / b, - z = a.z / b} + return fast_new( + a.x / b, + a.y / b, + a.z / b + ) end end +function metatable.__div(a, b) + -- scalar/vector makes no sense + return fast_new( + a.x / b, + a.y / b, + a.z / b + ) +end + +-- misc stuff function vector.offset(v, x, y, z) - return {x = v.x + x, - y = v.y + y, - z = v.z + z} + return fast_new( + v.x + x, + v.y + y, + v.z + z + ) end function vector.sort(a, b) - return {x = math.min(a.x, b.x), y = math.min(a.y, b.y), z = math.min(a.z, b.z)}, - {x = math.max(a.x, b.x), y = math.max(a.y, b.y), z = math.max(a.z, b.z)} + return fast_new(math.min(a.x, b.x), math.min(a.y, b.y), math.min(a.z, b.z)), + fast_new(math.max(a.x, b.x), math.max(a.y, b.y), math.max(a.z, b.z)) +end + +function vector.check(v) + return getmetatable(v) == metatable end local function sin(x) @@ -213,7 +333,7 @@ end function vector.dir_to_rotation(forward, up) forward = vector.normalize(forward) - local rot = {x = math.asin(forward.y), y = -math.atan2(forward.x, forward.z), z = 0} + local rot = vector.new(math.asin(forward.y), -math.atan2(forward.x, forward.z), 0) if not up then return rot end @@ -221,7 +341,7 @@ function vector.dir_to_rotation(forward, up) "Invalid vectors passed to vector.dir_to_rotation().") up = vector.normalize(up) -- Calculate vector pointing up with roll = 0, just based on forward vector. - local forwup = vector.rotate({x = 0, y = 1, z = 0}, rot) + local forwup = vector.rotate(vector.new(0, 1, 0), rot) -- 'forwup' and 'up' are now in a plane with 'forward' as normal. -- The angle between them is the absolute of the roll value we're looking for. rot.z = vector.angle(forwup, up) |