1 files changed, 66 insertions, 0 deletions
diff --git a/tex/context/modules/mkiv/s-present-random.lua b/tex/context/modules/mkiv/s-present-random.lua
new file mode 100644
index 000000000..f32d7aaea
--- /dev/null
+++ b/tex/context/modules/mkiv/s-present-random.lua
@@ -0,0 +1,66 @@
+if not modules then modules = { } end modules ['present-random'] = {
+    version   = 1.001,
+    comment   = "companion to s-present-random.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+-- For the moment we keep the namespace steps because it can become some
+-- shared module some day.
+
+moduledata.steps = moduledata.steps or { }
+local steps      = moduledata.steps
+
+local locations = {
+    'lefttop',
+    'middletop',
+    'righttop',
+    'middleleft',
+    'middle',
+    'middleright',
+    'leftbottom',
+    'middlebottom',
+    'rightbottom',
+}
+
+local done, current, previous, n
+
+function steps.reset_locations()
+    done, current, previous, n = table.tohash(locations,false), 0, 0, 0
+end
+
+function steps.next_location(loc)
+    previous = current
+    n = n + 1
+    loc = loc and loc ~= "" and tonumber(loc)
+    while true do
+        current = loc or math.random(1,#locations)
+        if not done[current] then
+            done[current] = true
+            break
+        end
+    end
+end
+
+function steps.current_location()
+    context(locations[current] or "")
+end
+
+function steps.previous_location()
+    context(locations[previous] or "")
+end
+
+function steps.current_n()
+    context(current)
+end
+
+function steps.previous_n()
+    context(previous)
+end
+
+function steps.step()
+    context(n)
+end
+
+steps.reset_locations()