Get some cart upgrades in there.

Replace "key" => value with a simple object of component replacements.

src/bouncer-coroutine.lua.bak

@@ -1,42 +0,0 @@
-function bouncer(v)
-    return function()
-        local h0 = 0.1 -- m/s
-        -- local v = 10 -- m/s, current velocity
-        local g = 10 -- m/s/s
-        local t = 0 -- starting time
-        local rho = 0.60 -- coefficient of restitution
-        local tau = 0.10 -- contact time for bounce
-        local hmax = h0 -- keep track of the maximum height
-        local h = h0
-        local hstop = 0.01 -- stop when bounce is less than 1 cm
-        local freefall = true -- state: freefall or in contact
-        local t_last = -math.sqrt(2 * h0 / g) -- time we would have launched to get to h0 at t=0
-        local vmax = math.sqrt(v * g)
-
-        while hmax > hstop do
-            local dt = coroutine.yield(h, not freefall)
-            if freefall then
-                local hnew = h + v * dt - 0.5 * g * dt * dt
-                if hnew < 0 then
-                    -- Bounced!
-                    t = t_last + 2 * math.sqrt(2 * hmax / g)
-                    freefall = false
-                    t_last = t + tau
-                    h = 0
-                else
-                    t = t + dt
-                    v = v - g * dt
-                    h = hnew
-                end
-            else
-                t = t + tau
-                vmax = vmax * rho
-                v = vmax
-                freefall = true
-                h = 0
-            end
-            hmax = 0.5 * vmax * vmax / g
-        end
-        return 0
-    end
-end

src/cart.lua

@@ -12,8 +12,8 @@ function Cart.reset(o)
         y = 50,
     }
     o.velocity = {
-        x = 300 + (100 * math.random()),
+        x = o.baseVelocity.x + (100 * math.random()),
-        y = 175 * (math.random() - 1),
+        y = o.baseVelocity.y * math.random(),
     }
     o.size = size
     o.canBeBounced = {
@@ -49,5 +49,10 @@ function Cart.reset(o)
 end
 
 function Cart.new()
-    return setmetatable(Cart.reset({}), { __index = Cart })
+    return setmetatable(Cart.reset({
+        baseVelocity = {
+            x = 300,
+            y = -170,
+        }
+    }), { __index = Cart })
 end

src/main.lua

@@ -24,6 +24,7 @@ import("systems/rounds.lua")
 import("systems/camera-pan.lua")
 import("systems/collision-resolution.lua")
 import("systems/collision-detection.lua")
+import("systems/upgrade-utils.lua")
 
 import("systems/draw.lua")
 import("systems/input.lua")
@@ -37,7 +38,6 @@ local gfx <const> = playdate.graphics
 playdate.display.setRefreshRate(50)
 gfx.setBackgroundColor(gfx.kColorWhite)
 
-cart = Cart.new()
 local floorSize = { x = 10000, y = 10 }
 floor = {
     position = { x = 0, y = 235 },
@@ -67,7 +67,7 @@ function Score:draw()
 end
 
 world:addEntity(floor)
-world:addEntity(cart)
+world:addEntity(Cart.new())
 addAllSpawners(world)
 
 world:addEntity(Ingredients.getFirst())

src/systems/filter-types.lua

@@ -13,8 +13,7 @@ local SOME_TABLE <const> = {}
 ---@alias Entity table
 ---@alias InRelations Entity[]
 ---@alias InputState { receivedInputThisFrame: boolean, aJustPressed: boolean, bJustPressed: boolean, upJustPressed: boolean, downJustPressed: boolean, leftJustPressed: boolean, rightJustPressed: boolean }
----@alias ReplaceRelation { entityToModify: Entity, replacement: Replacement }
+---@alias ReplaceRelation { entityToModify: Entity, replacement: table }
----@alias Replacement { key: string, value: AnyComponent }
 ---@alias RoundStateAction "end" | "start"
 ---@alias Selectable { additions: Entity[] | nil, replacements: ReplaceRelation[] | nil, highlighted: boolean, navigateDown: Selectable | nil, navigateUp: Selectable | nil  }
 ---@alias XyPair { x: number, y: number }
@@ -67,9 +66,6 @@ T = {
     ---@type ReplaceRelation
     ReplaceRelation = SOME_TABLE,
 
-    ---@type Replacement
-    Replacement = SOME_TABLE,
-
     ---@type RoundStateAction
     RoundStateAction = "start",
 

src/systems/filter-types.lua2p

@@ -66,8 +66,7 @@ local SOME_TABLE <const> = {}
     CanBeBounced = "{ flat: XyPair, mult = XyPair }",
     InputState = "{ receivedInputThisFrame: boolean, aJustPressed: boolean, bJustPressed: boolean, upJustPressed: boolean, downJustPressed: boolean, leftJustPressed: boolean, rightJustPressed: boolean }",
 
-    Replacement = "{ key: string, value: AnyComponent }",
+    ReplaceRelation = "{ entityToModify: Entity, replacement: table }",
-    ReplaceRelation = "{ entityToModify: Entity, replacement: Replacement }",
     Selectable = "{ additions: Entity[] | nil, replacements: ReplaceRelation[] | nil, highlighted: boolean, navigateDown: Selectable | nil, navigateUp: Selectable | nil  }",
 }))
 

src/systems/menu.lua

@@ -1,10 +1,10 @@
 ---@param relation ReplaceRelation
 ---@param world World
 local function applyReplacementRelation(relation, world)
-    printTable(relation.entityToModify)
+    for k, v in pairs(relation.replacement) do
-    relation.entityToModify[relation.replacement.key] = relation.replacement.value
+        relation.entityToModify[k] = v
+    end
     world:addEntity(relation.entityToModify)
-    printTable(relation.entityToModify)
 end
 
 menuController = filteredSystem("menuController", { menuItems = Arr(T.Selectable), inputState = T.InputState }, function(e, _, system)

src/systems/rounds.lua

@@ -102,8 +102,8 @@ roundSystem = filteredSystem("round", { roundAction = T.RoundStateAction, positi
             system.world:removeEntity(collectable)
         end
 
-        ---@type SpawnerUpgrade[]
+        ---@type NamedUpgrade[]
-        local availableUpgrades = Utils.getNDifferentValues(getAvailableSpawnerUpgrades(), 3)
+        local availableUpgrades = Utils.getNDifferentValues(getAvailableUpgrades(), 3)
         -- Sorting from shortest to longest sort of makes them look like a bun?
         table.sort(availableUpgrades, function(a, b)
             return #a.name > #b.name

src/systems/spawner.lua

@@ -62,7 +62,7 @@ function addAllSpawners(world)
         local size = { x = sizeX, y = sizeY / 2 }
 
         world:addEntity({
-            -- NOTE: This name should NOT be used to identify the spawner.
+            -- NOTE: This name should NOT be used to *identify* the spawner.
             -- It should only be used to supply visual information when searching for available upgrades.
             name = name,
             odds = spawnerOdds,
@@ -101,43 +101,3 @@ function addAllSpawners(world)
     })
 end
 
----@alias SpawnerUpgrade { name: string, replace: ReplaceRelation }
-
----@return SpawnerUpgrade[]
-function getAvailableSpawnerUpgrades()
-    ---@type SpawnerUpgrade[]
-    local upgrades = {}
-    for _, spawner in pairs(spawnerSystem.entities) do
-        -- if spawner.hasUpgradeSpeed then
-        --     upgrades[#upgrades + 1] = { hasUpgradeSpeed = spawner.hasUpgradeSpeed }
-        -- end
-
-        local entityToSpawn = spawner.canSpawn.entityToSpawn
-        if entityToSpawn.score then
-            upgrades[#upgrades + 1] = {
-                name = "Double " .. spawner.name .. " value",
-                replace = {
-                    entityToModify = entityToSpawn,
-                    replacement = {
-                        key = "score",
-                        value = entityToSpawn.score * 2,
-                    },
-                },
-            }
-        end
-
-        assert(spawner.odds, "Expected all spawners to have an `odds` field!")
-        upgrades[#upgrades + 1] = {
-            name = "Double " .. spawner.name .. " frequency",
-            replace = {
-                entityToModify = entityToSpawn,
-                replacement = {
-                    key = "odds",
-                    value = entityToSpawn.odds,
-                }
-            },
-        }
-    end
-
-    return upgrades
-end

src/systems/upgrade-utils.lua

@@ -0,0 +1,77 @@
+---@alias NamedUpgrade { name: string, replace: ReplaceRelation }
+
+--- Appends available upgrades to the given upgrades array.
+---@param upgrades NamedUpgrade[]
+function getAvailableSpawnerUpgrades(upgrades)
+    for _, spawner in pairs(spawnerSystem.entities) do
+        -- if spawner.hasUpgradeSpeed then
+        --     upgrades[#upgrades + 1] = { hasUpgradeSpeed = spawner.hasUpgradeSpeed }
+        -- end
+
+        local entityToSpawn = spawner.canSpawn.entityToSpawn
+        if entityToSpawn.score then
+            upgrades[#upgrades + 1] = {
+                name = "Double " .. spawner.name .. " value",
+                replace = {
+                    entityToModify = entityToSpawn,
+                    replacement = {
+                        score = entityToSpawn.score * 2,
+                    },
+                },
+            }
+        end
+
+        assert(spawner.odds, "Expected all spawners to have an `odds` field!")
+        upgrades[#upgrades + 1] = {
+            name = "Double " .. spawner.name .. " frequency",
+            replace = {
+                entityToModify = spawner,
+                replacement = {
+                    odds = spawner.odds,
+                }
+            },
+        }
+    end
+end
+
+--- Appends available upgrades to the given upgrades array.
+---@param upgrades NamedUpgrade[]
+function getAvailableCartUpgrades(upgrades)
+    for _, cart in pairs(cartSystem.entities) do
+        upgrades[#upgrades + 1] = {
+            name = "10% Lighter Cart",
+            replace = {
+                entityToModify = cart,
+                replacement = {
+                    mass = cart.mass * 0.9
+                }
+            },
+        }
+        upgrades[#upgrades + 1] = {
+            name = "+20% Cart Launch Right",
+            replace = {
+                entityToModify = cart.baseVelocity,
+                replacement = {
+                    x = cart.baseVelocity.x * 1.2
+                }
+            },
+        }
+        upgrades[#upgrades + 1] = {
+            name = "+20% Cart Launch Up",
+            replace = {
+                entityToModify = cart.baseVelocity,
+                replacement = {
+                    y = cart.baseVelocity.y * 1.2
+                }
+            },
+        }
+    end
+end
+
+---@return NamedUpgrade[]
+function getAvailableUpgrades()
+    local upgrades = {}
+    getAvailableSpawnerUpgrades(upgrades)
+    getAvailableCartUpgrades(upgrades)
+    return upgrades
+end