Fixed profile tool.

Project.toml

@@ -17,7 +17,9 @@ StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 ArchGDAL = "0.7 - 0.9"
 CoordinateTransformations = "0.5 - 0.6"
 GeoFormatTypes = "0.4"
+GeoInterface = "1"
 GeoStatsBase = "0.21 - 0.25"
+IterTools = "1"
 RecipesBase = "0.7, 0.8, 1.0"
 StaticArrays = "0.12, 1.0"
 julia = "1.6 - 1"

src/geoutils.jl

@@ -261,18 +261,19 @@ function profile!(values, ga, a, b, band)
 
     δx = i1 - i0
     δy = j1 - j0
-    δe = abs(δy / δx)
-    er = 0.0
-
-    j = j0
-    ystep = δy > 0 ? 1 : -1
-    xstep = i0 < i1 ? 1 : -1
-    for i in i0:xstep:i1
-        push!(values, ga[i, j, band])
-        er += δe
-        if er > 0.5
-            j += ystep
-            er -= 1.0
+
+    if abs(δx) >= abs(δy)
+        j = j0
+        xstep = δx > 0 ? 1 : -1
+        for (d, i) in enumerate(i0:xstep:i1)
+            push!(values, ga[i, j+div((d - 1) * δy, abs(δx), RoundNearest), band])
+        end
+    else
+        i = i0
+        ystep = δy > 0 ? 1 : -1
+        for (d, j) in enumerate(j0:ystep:j1)
+            push!(values, ga[i+div((d - 1) * δx, abs(δy), RoundNearest), j, band])
         end
     end
+    return indices
 end

test/test_geoutils.jl

@@ -77,6 +77,12 @@ const tbbox = (min_x=440720.0, min_y=3.74532e6, max_x=446720.0, max_y=3.75132e6)
         ga = GeoArray(rand(4, 4))
         values = GeoArrays.profile(ga, LineString())
         @test length(values) == 3
+
+        GI.getgeom(::GI.LineStringTrait, ::LineString) = [[3, 4], [1, 2]]
+        values2 = GeoArrays.profile(ga, LineString())
+        @test length(values2) == 3
+        @test values == reverse(values2)
+
     end
 
 end