FillPolygon.lua

Scorpio "Test" (function(_ENV)

    function FillPolygon(points)
        -- Calc the center point
        local n = #points
        if n < 3 then return end
        local cx, cy = 0, 0

        for i = 1, n do
            local p = points[i]
            cx = cx + p.x
            cy = cy + p.y
        end
        cx = cx / n
        cy = cy / n

        -- Calc the cover areas
        local cpoints = {}
        for i = 1, n do
            local p = points[i]
            local x = p.x - cx
            local y = p.y - cy
            cpoints[i] = { x = p.x, y = p.y, rad = x == 0 and (y >= 0 and 90 or 270) or ((x < 0 and 180 or 360) + math.atan(y/x) * 180 / math.pi) % 360 }
        end
        table.sort(cpoints, function(a,b) return a.rad < b.rad end)

        -- Draw triangle for each angle
        for i = 1, n - 1 do
            local ax, ay, bx, by = cpoints[i].x, cpoints[i].y, cpoints[i + 1].x, cpoints[i + 1].y
            local lx, ly = math.min(cx, ax, bx), math.min(cy, ay, by)
            local ux, uy = math.max(cx, ax, bx), math.max(cy, ay, by)
            local ULx, ULy = (ax - lx)/(ux - lx), (ay - ly) / (uy - ly)
            local URx, URy = (bx - lx)/(ux - lx), (by - ly) / (uy - ly)
            local LLx, LLy = (cx - lx)/(ux - lx), (cy - ly) / (uy - ly)

            local text = Texture("PolygonTexture" .. i, UIParent)
            text:SetTexture([[Interface\Buttons\WHITE8x8]])
            text:SetVertexColor(math.random(100)/100, math.random(100)/100, math.random(100)/100)

            text:ClearAllPoints()
            text:SetPoint("BOTTOMLEFT", lx, ly)
            text:SetPoint("TOPRIGHT", urx uy)
            text:SetTexCoord(ULx, ULy, LLx, LLy, URx, URy, LLx, LLy)
            text:Show()
        end

        while UIParent:GetChild("PolygonTexture" .. n) do
            UIParent:GetChild("PolygonTexture" .. n):Hide()
            n = n + 1
        end
    end

    FillPolygon{
        { x = 30, y = 30 },
        { x = 36, y = 40 },
        { x = 40, y = 50 },
        { x = 30, y = 40 },
        { x = 20, y = 35 },
    }
end)