57 lines
1.1 KiB
Lua
57 lines
1.1 KiB
Lua
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--
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-- Helper functions
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--
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cart_func = {}
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function cart_func:get_sign(z)
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if z == 0 then
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return 0
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else
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return z/math.abs(z)
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end
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end
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-- Returns the velocity as a unit vector
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-- The smaller part of the vector will be turned to 0
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function cart_func:velocity_to_dir(v)
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if math.abs(v.x) > math.abs(v.z) then
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return {x=cart_func:get_sign(v.x), y=cart_func:get_sign(v.y), z=0}
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else
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return {x=0, y=cart_func:get_sign(v.y), z=cart_func:get_sign(v.z)}
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end
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end
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function cart_func:is_rail(p)
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local nn = minetest.env:get_node(p).name
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return minetest.get_item_group(nn, "rail") ~= 0
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end
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function cart_func:is_int(z)
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z = math.abs(z)
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return math.abs(math.floor(z+0.5)-z) <= 0.1
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end
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cart_func.v3 = {}
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function cart_func.v3:add(v1, v2)
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return {x=v1.x+v2.x, y=v1.y+v2.y, z=v1.z+v2.z}
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end
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function cart_func.v3:copy(v)
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return {x=v.x, y=v.y, z=v.z}
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end
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function cart_func.v3:round(v)
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return {
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x = math.floor(v.x+0.5),
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y = math.floor(v.y+0.5),
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z = math.floor(v.z+0.5),
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}
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end
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function cart_func.v3:equal(v1, v2)
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return v1.x == v2.x and v1.y == v2.y and v1.z == v2.z
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end
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