Replace Frag Grenades with Plasma for SAPP

-- Replace Frag Grenades with Plasma by H® Shaft for SAPP

-- This script will:
-- Set Frag and Plasma Grenade counts to what you specify
-- Replace both the frag grenade equipment and projectile with the plasma grenade equipment and projectiles
-- will only work with UNPROTECTED maps with stock frags and plasma grenades

-- requested by @Captain@

-- If you would like to do the opposite; replace Plasma Grenades with Frags, see other script. http://pastebin.com/tkWh9bCZ

-- set grenade counts to what you want them. I suggest leaving 'frag'_count to 0 (zero)
-- Note: frag count will show, but only plasma will be thrown/picked up.

frag_count = 0
plasma_count = 2

-- sapp api version
api_version = "1.8.0.0"
-- do not edit below unless you know what you are doing --
game_started = false

function OnScriptLoad()
    register_callback(cb['EVENT_GAME_START'],"OnNewGame")
    register_callback(cb['EVENT_GAME_END'],"OnGameEnd")
    register_callback(cb['EVENT_SPAWN'],"OnPlayerSpawn")
    register_callback(cb['EVENT_OBJECT_SPAWN'],"OnObjectSpawn")
end

function OnScriptUnload() end

function OnPlayerSpawn(PlayerIndex)
    if (game_started == true) then

        -- set grenade counts as they are set above
        if (player_alive(PlayerIndex) == true) then
            local player_object = get_dynamic_player(PlayerIndex)
            safe_write(true)
            write_word(player_object + 0x31E, frag_count)
            write_word(player_object + 0x31F, plasma_count)
            safe_write(false)
        end

    end
end

function OnObjectSpawn(PlayerIndex, MapID, ParentID, ObjectID)
    if (game_started == true) then
        -- Note: you cannot replace one object type for another, they must be the same type.
        -- obj_types: vehi, weap, bipd, eqip, proj
        -- obj_names: there are many, example: "weapons\\plasma grenade\\plasma grenade"

        -- replace frag grenade eqip/equipment with plasma grenades:
        if MapID == get_tag_info("eqip", "weapons\\frag grenade\\frag grenade") then
            return true, get_tag_info("eqip", "weapons\\plasma grenade\\plasma grenade")
        end

        -- replace frag grenade proj/projectiles with plasma projectiles (doesn't happen until you throw):
        if MapID == get_tag_info("proj", "weapons\\frag grenade\\frag grenade") then
            return true, get_tag_info("proj", "weapons\\plasma grenade\\plasma grenade")
        end

        -- end --
        return true
    else
        return false
    end
end

-- note: calls to this function must provide both arguments of obj_type & obj_name separated by comma as shown above.
function get_tag_info(obj_type, obj_name)
    local tag_id = lookup_tag(obj_type, obj_name)
    return tag_id ~= 0 and read_dword(tag_id + 0xC) or nil
end

function OnNewGame()
    game_started = true
end

function OnGameEnd()
    game_started = false
end

-- Created by H® Shaft
-- Visit http://halorace.org/forum/index.php