Fix TriRefinement to match docstring (#1291)

* Fix TriRefinement to match docstring

* Fix test

Author: juliohm

src/refinement/tri.jl

@@ -18,7 +18,6 @@ TriRefinement() = TriRefinement(nothing)
 
 function refine(mesh, method::TriRefinement)
   assertion(paramdim(mesh) == 2, "TriRefinement only defined for surface meshes")
-  (eltype(mesh) <: Triangle) || return simplexify(mesh)
 
   # retrieve geometry and topology
   points = vertices(mesh)

test/refinement.jl

@@ -1,27 +1,32 @@
 @testitem "TriRefinement" setup = [Setup] begin
   # CRS propagation
   grid = CartesianGrid((3, 3), merc(0, 0), (T(1), T(1)))
-  ref = refine(grid, TriRefinement())
-  @test crs(ref) === crs(grid)
+  rgrid = refine(grid, TriRefinement())
+  @test crs(rgrid) === crs(grid)
+
+  # quadrangles are divided into 4 triangles
+  grid = cartgrid(10, 10)
+  rgrid = refine(grid, TriRefinement())
+  @test nelements(rgrid) == 4 * nelements(grid)
 
   # predicate
   points = cart.([(0, 0), (4, 0), (8, 0), (3, 1), (5, 1), (2, 2), (4, 2), (6, 2), (4, 4)])
   connec = connect.([(1, 2, 6), (2, 3, 8), (6, 8, 9), (2, 5, 4), (4, 5, 7), (4, 7, 6), (5, 8, 7)])
   mesh = SimpleMesh(points, connec)
-  ref = refine(mesh, TriRefinement(e -> measure(e) > T(1) * u"m^2"))
-  @test nelements(ref) == 13
-  @test nvertices(ref) == 12
-  ref = refine(mesh, TriRefinement(e -> measure(e) ≤ T(1) * u"m^2"))
-  @test nelements(ref) == 15
-  @test nvertices(ref) == 13
+  rmesh = refine(mesh, TriRefinement(e -> measure(e) > T(1) * u"m^2"))
+  @test nelements(rmesh) == 13
+  @test nvertices(rmesh) == 12
+  rmesh = refine(mesh, TriRefinement(e -> measure(e) ≤ T(1) * u"m^2"))
+  @test nelements(rmesh) == 15
+  @test nvertices(rmesh) == 13
 
   # latlon
   points = latlon.([(0, 0), (0, 4), (0, 8), (1, 3), (1, 5), (2, 2), (2, 4), (2, 6), (4, 4)])
   connec = connect.([(1, 2, 6), (2, 3, 8), (6, 8, 9), (2, 5, 4), (4, 5, 7), (4, 7, 6), (5, 8, 7)])
   mesh = SimpleMesh(points, connec)
-  ref = refine(mesh, TriRefinement())
-  @test nelements(ref) == 21
-  @test nvertices(ref) == 16
+  rmesh = refine(mesh, TriRefinement())
+  @test nelements(rmesh) == 21
+  @test nvertices(rmesh) == 16
 end
 
 @testitem "QuadRefinement" setup = [Setup] begin
@@ -117,5 +122,5 @@ end
   mesh = topoconvert(SimpleTopology, grid)
   rmesh = refine(mesh)
   @test eltype(rmesh) <: Triangle
-  @test nelements(rmesh) == 200
+  @test nelements(rmesh) == 400
 end