Weight System

Object Weights

(Added in 1531zeebee)

With the object_weights optional feature enabled, every object in the game is now polled based on a weight value that is assigned to it. By default, this value is 10. These polls do not mirror seeded values when the feature is not enabled. To assign a non-default weight to any of your objects, add weight = X to your object definitions. The internal system will then respect this value when deciding which objects to choose in all areas of the game.

You can also add get_weight = function(self, weight) to any of your objects if they have internal ways of modifying their own weight. This function should returned the modified weight value.

Due to these changes, there is now a new polling function that you should use whenever you need to select an object. This will ensure that you are respecting object weights, and any modifications to them that people have made.

SMODS.poll_object(args) -> string|nil

This function returns a key of an object that is appropriate for the args that you provide. If there are no matches (for example if a chance roll fails), it will not return a value. The following arguments are supported:

• type: specify a single type (or attribute) to poll
• types: Table[string] specify a table of types to poll
• rarities: Table[string] specify a table of rarities to include (only for standard object types)
  
  
• pool: Table[string] specify a table of object keys to use as the pool instead of having the function generate one
  
  
• filter: function(pool) -> Table[{key = string, type = string}] specify a function to filter the pool once it has been generated, must return the modified pool
• chance: % of success as a decimal value 0-1, editions, enhancements and seals have a default chance internally
• mod: multiplier to the base chance
• seed: specify a seed to use for the poll chance (defaults are available)
• type_key: a second poll seed if repolling is used
• append: appended onto the poll seed
• guaranteed: set to true to override default chance
• no_negative: swaps negative edition to polychrome for vanilla functionality when true
• blind_type: can be set to "boss", "big", or "small" to select an appropriate boss (NOTE: currently there is no use of big and small blinds)
  
  
• print: set to true to display debug messages (useful for understanding your pool) Arguments to poll attributes (default behaviour is to find an object that matches all attributes)
• attributes: Table[string] specify a table of attributes to poll (preferred for attribute polling)
• union: set to true to switch to join each set rather than find the intersection
• rarity: attribute polling respects rarity by default. Set this to a rarity key to select a specific rarity, or set to false to ignore rarity completely
• closest_match: set to true to stop the pool becoming completely empty due to a lack of matching attributes (NOTE: attributes are found in the order they are given)
• allow_duplicates: set to true to allow duplicates to be given
• allow_legendaries: set to true to allow legendaries to be included (NOTE: if the pool consists of only legendary objects, they are always allowed)

Example filter:

-- Filter cards that are compatible with Eternal
filter = function(pool)
    local all_unavailable = true
    for _, v in ipairs(pool) do
        local center = G.P_CENTERS[v.key]
        if not center or not center.eternal_compat then
            v.key = "UNAVAILABLE" -- This is done to preserve RNG
        else
            all_unavailable = false
        end
    end
    if all_unavailable then
        pool[#pool+1] = {key = 'j_joker', type = "Joker"} -- Default if the entire pool is unavailable
    end
    return pool
end

Utility

Modifying weights through calculation

A context has been added to adjust any weighted pool when it is being created.

context.modify_weights

This context is used to modify weights in SMODS.poll_object when the object_weights optional feature is enabled.

if context.modify_weights then

context.modify_weights -- flag to identify this context, always TRUE
context.pool -- the booster pack center that has ended
context.pool_types

The pool is structured as a table of tables, where each table is structured as below. Modifying the weight value in this table will affect the final weighted table to be used.

{key = 'object_key', weight = number_of_weight}

Adding alternate objects

New object types should work fine with this system, but may need some extra set up in certain scenarios.

• If your object should only have a chance of being successful, you can set a base chance that will always be used by adding SMODS.base_rate_percentage[type_key] = X where X is a number 0-1 that represents the percent chance of generating your object. (for example, editions have 0.04)
• If your object that relies on chance should use the chance roll as it's poll amount (like Editions), add SMODS.no_repoll[type_key] = true.
• If your object needs to modify the type polling key in a specific way other than default, add SMODS.poll_keys[type_key] = {str = 'new_key', block_infill = true or false, ante = true or false}. You can see how these affect the key by looking at SMODS.get_poll_key in src/utils/weights.lua.
• If your object isn't stored in G.P_CENTERS, you can add SMODS.game_table_from_type[type_key] = table.