c_gtk_snapshot_append_outset_shadow

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
void function(GtkSnapshot* snapshot, GskRoundedRect* outline, GdkRGBA* color, float dx, float dy, float spread, float blurRadius) c_gtk_snapshot_append_outset_shadow;

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