libs/lua-math-polygon: spaces after commas, rm unneded parentheses, simplify rectangle convert function

Signed-off-by: Jan-Tarek Butt <tarek@ring0.de>

libs/lua-math-polygon/src/math-polygon.lua

@@ -2,19 +2,19 @@ local M = {}
 
 -- Source with pseudocode: https://de.wikipedia.org/wiki/Punkt-in-Polygon-Test_nach_Jordan
 -- see also https://en.wikipedia.org/wiki/Point_in_polygon
--- parameters: points A = (x_a,y_a), B = (x_b,y_b), C = (x_c,y_c)
+-- parameters: points A = (x_a, y_a), B = (x_b, y_b), C = (x_c, y_c)
 -- return value: −1 if the ray from A to the right bisects the edge [BC] (the lower vortex of [BC]
 -- is not seen as part of [BC]);
 --                0 if A is on [BC];
 --                +1 else
-function M.cross_prod_test(x_a,y_a,x_b,y_b,x_c,y_c)
+function M.cross_prod_test(x_a, y_a, x_b, y_b, x_c, y_c)
 	if y_a == y_b and y_b == y_c then
 		if (x_b <= x_a and x_a <= x_c) or (x_c <= x_a and x_a <= x_b) then
 			return 0
 		end
 		return 1
 	end
-	if not ((y_a == y_b) and (x_a == x_b)) then
+	if not (y_a == y_b and x_a == x_b) then
 		if y_b > y_c then
 			-- swap b and c
 			local h = x_b
@@ -24,7 +24,7 @@ function M.cross_prod_test(x_a,y_a,x_b,y_b,x_c,y_c)
 			y_b = y_c
 			y_c = h
 		end
-		if (y_a <= y_b) or (y_a > y_c) then
+		if y_a <= y_b or y_a > y_c then
 			return 1
 		end
 		local delta = (x_b-x_a) * (y_c-y_a) - (y_b-y_a) * (x_c-x_a)
@@ -46,7 +46,7 @@ end
 --                0 if Q on an edge of P
 function M.point_in_polygon(poly, point)
 	local t = -1
-	for i=1,#poly-1 do
+	for i=1, #poly-1 do
 		t = t * M.cross_prod_test(point.lon,point.lat,poly[i].lon,poly[i].lat,poly[i+1].lon,poly[i+1].lat)
 		if t == 0 then break end
 	end
@@ -55,16 +55,12 @@ end
 
 -- Convert rectangle defined by two point into polygon
 function M.two_point_rec_to_poly(rec)
-	local poly = {};
-	poly[1]["lon"] = rec[1].lon
-	poly[1]["lat"] = rec[1].lat
-	poly[2]["lon"] = rec[2].lon
-	poly[2]["lat"] = rec[1].lat
-	poly[3]["lon"] = rec[2].lon
-	poly[3]["lat"] = rec[2].lat
-	poly[4]["lon"] = rec[1].lon
-	poly[4]["lat"] = rec[2].lat
-	return poly
+	return {
+		rec[1],
+		{ lon = rec[2].lon, lat = rec[1].lat },
+		rec[2],
+		{ lon = rec[1].lon, lat = rec[2].lat },
+	}
 end
 
 return M