add vertices to generate correct normals

Author: ffreyer

src/rectangles.jl

@@ -551,7 +551,15 @@ function coordinates(rect::Rect3D, nvertices=nothing)
     # TODO use n
     w = widths(rect)
     o = origin(rect)
-    return (ntuple(j-> o[j] + ((i >> (j - 1)) & 1) * w[j], 3) for i in 0:7)
+    return map(x -> Point3f0(x .* w .+ o), [
+        [0, 0, 0], [0, 0, 1], [0, 1, 1], [0, 1, 0],
+        [0, 0, 0], [1, 0, 0], [1, 0, 1], [0, 0, 1],
+        [0, 0, 0], [0, 1, 0], [1, 1, 0], [1, 0, 0],
+
+        [1, 1, 1], [0, 1, 1], [0, 0, 1], [1, 0, 1],
+        [1, 1, 1], [1, 0, 1], [1, 0, 0], [1, 1, 0],
+        [1, 1, 1], [1, 1, 0], [0, 1, 0], [0, 1, 1]
+    ])
 end
 
 function texturecoordinates(rect::Rect3D, nvertices=1)
@@ -560,11 +568,11 @@ end
 
 function faces(rect::Rect3D, nvertices=1)
     return QuadFace{Int}[
-        (1,3,4,2),
-        (2,4,8,6),
-        (4,3,7,8),
-        (1,5,7,3),
-        (1,2,6,5),
-        (5,6,8,7),
+        (1,2,3,4),
+        (5,6,7,8),
+        (9,10,11,12),
+        (13,14,15,16),
+        (17,18,19,20),
+        (21,22,23,24),
     ]
 end