box_sym.lua


NAME
    box_sym

FUNCTION
    box_sym(plot, arr, dx)

NOTES
    Adds box symbols to the plot.

INPUTS
    plot   - zePlot object
    arr    - zeArray object having 3 vectors containing data of x, y, and dy
    size   - symbol with in plot coordinate

OUTPUTS
    a zePolygon object.

SOURCE

require("register")

function box_sym(plot, arr, size)
    local node, shape, xyz = zeGrf.new("node", "polygon", "vertex")
    plot:add(shape)
    shape:set{vertex = xyz, type = "quads"}
    local n = arr:size()
    local dx = size / 2
    for i = 1, n do
        local x = arr:getele(i-1, 0)
        local y = arr:getele(i-1, 1)
        local dy = arr:getele(i-1, 2)
        local z = 0
        xyz:add(x - dx, y - dy, z) 
        xyz:add(x + dx, y - dy, z) 
        xyz:add(x + dx, y + dy, z) 
        xyz:add(x - dx, y + dy, z)
    end
    return shape
end