diff --git a/R/smooth-data.R b/R/smooth-data.R
index 9901136bc..433f002ab 100644
--- a/R/smooth-data.R
+++ b/R/smooth-data.R
@@ -181,3 +181,30 @@
 
   newdata # return
 }
+
+#' @importFrom mgcv inSide
+`soap_film_data` <- function(smooth,
+    n = 100,
+    n_2d = NULL,
+    n_3d = NULL,
+    n_4d = NULL,
+    offset = NULL,
+    include_all = FALSE,
+    var_order = NULL) {
+  bnd <- boundary(smooth)
+
+  sub_bnd_data <- function(bnd, n = 100) {
+    l <- lapply(bnd, \(x) evenly(x, n = n))
+    d <- expand.grid(l) |>
+      as_tibble()
+    d
+  }
+
+  bnd_data <- lapply(bnd, FUN = sub_bnd_data, n = n) |>
+    bind_rows()
+
+  # are points inside boundary?
+  # Will deal with this in eval_smooth.soap.film because mgcv::inSide has a bad
+  # design
+  bnd_data
+}