Initial menu system by claude

instructions.txt

@@ -0,0 +1,55 @@
+
+Currently, my demo game includes a hotkey system.  You will use the
+existing hotkey system as inspiration to build a menu system.
+
+In my lua code, I can create a class such as "sphere."  Then
+I can create an instance of that class and make it appear in
+the world.
+
+I can also define a lua function "sphere.lookhotkeys" which adds
+hotkeys to objects of class sphere.  When I aim the crosshairs
+at a sphere, a widget WB_Hotkeys appears, and it shows me the
+hotkeys for spheres.
+
+I can then press one of those hotkeys.  The WB_Hotkeys widget
+handles the key event, displaying visual feedback, and it
+also invokes a lua function which eventually leads to the
+proper hotkey action being taken in lua.
+
+I want you to study this mechanism, learning exactly how this
+process works.  Then, I want you to implement a menu system
+that operates on exactly the same principles.
+
+Currently, my demo game contains a sphere and a cube which
+both have hotkeys.  I want you to reprogram the cube
+so that it has a menu instead of hotkeys.
+
+The menu system will require me to write a lua function
+such as cube.lookmenu, which generates the contents of the
+menu.  When I point the crosshairs at a cube, the menu
+widget WB_Menu will appear in minimized form.  In minimized
+form, the WB_Menu widget will just look like a little
+circle or something.  This is just enough of a clue to
+the user that a menu is there to be activated.
+
+When the user clicks the left mouse button, WB_Menu will
+switch to active form: it will display the menu and put
+the mouse pointer on the first menu item.  I can then
+drag the mouse and select a menu item, or I can drag off
+the menu to choose nothing.  When I release the mouse
+button, if the mouse is over a menu item, there's some
+visual feedback, and the appropriate lua closure is
+invoked.  Then, the menu goes back to minimized state.
+
+You must implement all of this using a combination of lua
+and blueprint-language.  No C++.  You can use the UE
+Wingman plugin to edit blueprints.
+
+Along the way, it is possible that the UE Wingman plugin may
+fail - it's still in beta.  If so, please pause, notify me,
+and you and I will work together to get things up and
+running again.
+
+
+
+

luprex/lua/login.lua

@@ -33,10 +33,10 @@ function moveto(x, y)
     tangible.animate{tan=actor, anim={action="moveto", xyz={x, y, z}, facing=math.auto}}
 end
 
-function cube.lookhotkeys(add)
+function cube.lookmenu(add)
-    add("Z", "Cube Hi", function () dprint("Doing Cube Hi") end)
+    add("Cube Hi", function () dprint("Doing Cube Hi") end)
-    add("X", "Cube Bye", function () dprint("Doing Cube Bye") end)
+    add("Cube Bye", function () dprint("Doing Cube Bye") end)
-    add("C", "Cube Yo", function () dprint("Doing Cube Yo") end)
+    add("Cube Yo", function () dprint("Doing Cube Yo") end)
 end
 
 function sphere.lookhotkeys(add)
@@ -60,6 +60,12 @@ function engio.getlookat()
         return "hotkeys"
     end
 
+    -- if the class has a function 'lookmenu', then the correct
+    -- look-at widget is 'menu'.
+    if class.lookmenu ~= nil then
+        return "menu"
+    end
+
     -- otherwise, if the class has a function 'getlookat', use that.
     if class.getlookat ~= nil then
         return class.getlookat()

luprex/lua/menu.lua

@@ -0,0 +1,68 @@
+----------------------------------------------------------------
+--
+-- To add a menu to an object (such as a Brick Oven), you will
+-- be adding a function 'lookmenu' to the appropriate class,
+-- like this:
+--
+-- function brickoven.lookmenu(add)
+--    add("Light Oven", function () ... end)
+--    add("Add Fuel", function () ... end)
+-- end
+--
+-- This function will get called twice: once in a 'probe' when
+-- Unreal wants to know what menu items exist, and a second time
+-- in an 'invoke' to find the right closure.  The 'add' function
+-- which is passed in can therefore be one of two functions.
+--
+-- In probe mode, the goal is to build up an array that looks
+-- like this:
+--
+--   {"Light Oven", "Add Fuel"}
+--
+-- So therefore, in probe mode, the 'add' function is a closure
+-- that adds the label to the array.
+--
+-- In invoke mode, the goal is to find the right closure.  So
+-- therefore, in invoke mode, the 'add' function is a closure
+-- that compares the label to the menu item which was already
+-- selected.  If there's a match, it records the closure.
+--
+----------------------------------------------------------------
+
+makeclass('engio')
+
+function engio.getmenu()
+    local class = tangible.getclass(place)
+
+    -- if the tangible doesn't have a 'lookmenu' function, do nothing
+    if class == nil or class.lookmenu == nil then
+        return {}
+    end
+
+    local items = {}
+    local add = function(label, closure)
+        table.insert(items, label)
+    end
+    class.lookmenu(add)
+    return items
+end
+
+function engio.pressmenu(label)
+    local class = tangible.getclass(place)
+
+    -- if the tangible doesn't have a 'lookmenu' function, do nothing
+    if class == nil or class.lookmenu == nil then
+        return
+    end
+
+    local result = nil
+    local add = function(lbl, closure)
+        if (lbl == label) then
+            result = closure
+        end
+    end
+    class.lookmenu(add)
+    if result ~= nil then
+        result()
+    end
+end