✨ Split a layer into tiles

Fixes #147

SimpleSDMLayers/Project.toml

@@ -1,7 +1,7 @@
 name = "SimpleSDMLayers"
 uuid = "2c645270-77db-11e9-22c3-0f302a89c64c"
 authors = ["Timothée Poisot <timothee.poisot@umontreal.ca>", "Gabriel Dansereau <gabriel.dansereau@umontreal.ca>"]
-version = "0.9.0"
+version = "0.9.1"
 
 [deps]
 Distances = "b4f34e82-e78d-54a5-968a-f98e89d6e8f7"

SimpleSDMLayers/src/SimpleSDMLayers.jl

@@ -40,6 +40,7 @@ include("operations/sliding.jl")
 include("operations/mask.jl")
 include("operations/rescale.jl")
 include("operations/mosaic.jl")
-export coarsen, slidingwindow, mask, rescale!, rescale, mosaic
+include("operations/tiling.jl")
+export coarsen, slidingwindow, mask, rescale!, rescale, mosaic, tile, tile!
 
 end # module

SimpleSDMLayers/src/operations/tiling.jl

@@ -0,0 +1,57 @@
+"""
+    tile!(tiles::Matrix{T}, layer::T, s::Tuple{Integer, Integer} = (5, 5)) where {T <: SimpleSDMLayer}
+
+Split a layer into a matrix of tiles (with size `s`), where the tiles are as
+evenly sized as possible, and have strictly matching boundaries.
+"""
+function tile!(
+    tiles::Matrix{T},
+    layer::T,
+    s::Tuple{Integer, Integer} = (5, 5),
+) where {T <: SimpleSDMLayer}
+    @assert s[1] < size(layer, 1)
+    @assert s[2] < size(layer, 2)
+    @assert size(tiles) == s
+    # Return type
+    RT = T <: SimpleSDMPredictor ? SimpleSDMPredictor : SimpleSDMResponse
+    # Boundaries from the bounding box
+    l = layer.left
+    r = layer.right
+    b = layer.bottom
+    t = layer.top
+    l_r_points = LinRange(l, r, s[2] + 1)
+    t_b_points = LinRange(t, b, s[1] + 1)
+    # Split the coordinates
+    dim_1_cutoff = floor.(Int, LinRange(1, size(layer, 1), s[1] + 1))
+    dim_2_cutoff = floor.(Int, LinRange(1, size(layer, 2), s[2] + 1))
+    # Add the layers to the tiles matrix
+    for i in eachindex(dim_1_cutoff)[2:end]
+        start1, stop1 = dim_1_cutoff[(i - 1):i]
+        for j in eachindex(dim_2_cutoff)[2:end]
+            start2, stop2 = dim_2_cutoff[(j - 1):j]
+            tiles[(i - 1), (j - 1)] =
+                RT(
+                    layer.grid[start1:stop1, start2:stop2],
+                    l_r_points[j - 1],
+                    l_r_points[j],
+                    t_b_points[i],
+                    t_b_points[i - 1],
+                )
+        end
+    end
+    return tiles
+end
+
+"""
+    tile(layer::T, s::Tuple{Integer, Integer} = (5, 5)) where {T <: SimpleSDMLayer}
+
+Split a layer into a matrix of tiles (with size `s`), where the tiles are as
+evenly sized as possible, and have strictly matching boundaries. This function
+will allocate the return matrix.
+"""
+function tile(layer::T, s::Tuple{Integer, Integer} = (5, 5)) where {T <: SimpleSDMLayer}
+    # Create the tiles
+    tiles = Matrix{T}(undef, s...)
+    tile!(tiles, layer, s)
+    return tiles
+end

docs/src/vignettes/layers/05_tiling.jl

@@ -0,0 +1,35 @@
+# # Splitting layers in tiles
+
+using SpeciesDistributionToolkit
+using CairoMakie
+
+# Get some data
+
+dataprovider = RasterData(EarthEnv, LandCover)
+spatial_extent = (left = -80.00, bottom = 43.19, right = -70.94, top = 46.93)
+trees = sum([
+    SimpleSDMPredictor(dataprovider; layer = i, full = true, spatial_extent...) for
+    i in 1:4
+])
+
+# split into tiles
+
+tiles = tile(trees, (4, 5))
+
+# plot
+
+tile_plot = heatmap(
+    tiles[1,2];
+    colormap = :Greens,
+    figure = (; resolution = (800, 350)),
+    axis = (;
+        aspect = DataAspect(),
+        xlabel = "Latitude",
+        ylabel = "Longitude",
+        title = "Relative tree cover",
+    ),
+)
+Colorbar(tile_plot.figure[:, end + 1], tile_plot.plot; height = Relative(0.5))
+current_figure()
+
+#