minetest/builtin/common/vector.lua
Paramat d04c41ad80 Vector functions: Fix vector.direction() function, improve documentation (#6801)
vector.direction() now returns a normalised vector with direction p1 to p2.
2017-12-21 20:57:42 +01:00

125 lines
2.1 KiB
Lua

vector = {}
function vector.new(a, b, c)
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}
end
return {x=0, y=0, z=0}
end
function vector.equals(a, b)
return a.x == b.x and
a.y == b.y and
a.z == b.z
end
function vector.length(v)
return math.hypot(v.x, math.hypot(v.y, v.z))
end
function vector.normalize(v)
local len = vector.length(v)
if len == 0 then
return {x=0, y=0, z=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)
}
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)
}
end
function vector.apply(v, func)
return {
x = func(v.x),
y = func(v.y),
z = 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))
end
function vector.direction(pos1, pos2)
return vector.normalize({
x = pos2.x - pos1.x,
y = pos2.y - pos1.y,
z = pos2.z - pos1.z
})
end
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}
else
return {x = a.x + b,
y = a.y + b,
z = a.z + b}
end
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}
else
return {x = a.x - b,
y = a.y - b,
z = a.z - b}
end
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}
else
return {x = a.x * b,
y = a.y * b,
z = a.z * b}
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}
else
return {x = a.x / b,
y = a.y / b,
z = a.z / b}
end
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)}
end