Data commit

Task/Pentagram/Lua/pentagram.lua

@@ -0,0 +1,28 @@
+local cos, sin, floor, pi = math.cos, math.sin, math.floor, math.pi
+
+function Bitmap:render()
+  for y = 1, self.height do
+    print(table.concat(self.pixels[y]))
+  end
+end
+
+function Bitmap:pentagram(x, y, radius, rotation, outlcolor, fillcolor)
+  local function pxy(i) return x+radius*cos(i*pi*2/5+rotation), y+radius*sin(i*pi*2/5+rotation) end
+  local x1, y1 = pxy(0)
+  for i = 1, 5 do
+    local x2, y2 = pxy(i*2) -- btw: pxy(i) ==> pentagon
+    self:line(floor(x1*2), floor(y1), floor(x2*2), floor(y2), outlcolor)
+    x1, y1 = x2, y2
+  end
+  self:floodfill(floor(x*2), floor(y), fillcolor)
+  radius = radius / 2
+  for i = 1, 5 do
+    x1, y1 = pxy(i)
+    self:floodfill(floor(x1*2), floor(y1), fillcolor)
+  end
+end
+
+bitmap = Bitmap(40*2,40)
+bitmap:clear(".")
+bitmap:pentagram(20, 22, 20, -pi/2, "@", '+')
+bitmap:render()