caching perf improvements - major improvements for immediate mode

FlexLove.lua

@@ -377,36 +377,37 @@ function flexlove.endFrame()
     end
   end
 
-  -- Save state back for all elements created this frame
+  -- Save state back for all elements created this frame (with diffing optimization)
   for _, element in ipairs(flexlove._currentFrameElements) do
     if element.id and element.id ~= "" then
-      local state = StateManager.getState(element.id, {})
+      -- Build state update object
+      local stateUpdate = {}
 
-      -- Save stateful properties back to persistent state
       -- Get event handler state
       if element._eventHandler then
         local eventState = element._eventHandler:getState()
         for k, v in pairs(eventState) do
-          state[k] = v
+          stateUpdate[k] = v
         end
       end
-      state._focused = element._focused
-      state._focused = element._focused
-      state._cursorPosition = element._cursorPosition
-      state._selectionStart = element._selectionStart
-      state._selectionEnd = element._selectionEnd
-      state._textBuffer = element._textBuffer
-      state._scrollX = element._scrollX
-      state._scrollY = element._scrollY
-      state._scrollbarDragging = element._scrollbarDragging
-      state._hoveredScrollbar = element._hoveredScrollbar
-      state._scrollbarDragOffset = element._scrollbarDragOffset
-      state._cursorBlinkTimer = element._cursorBlinkTimer
-      state._cursorVisible = element._cursorVisible
-      state._cursorBlinkPaused = element._cursorBlinkPaused
-      state._cursorBlinkPauseTimer = element._cursorBlinkPauseTimer
       
-      StateManager.setState(element.id, state)
+      stateUpdate._focused = element._focused
+      stateUpdate._cursorPosition = element._cursorPosition
+      stateUpdate._selectionStart = element._selectionStart
+      stateUpdate._selectionEnd = element._selectionEnd
+      stateUpdate._textBuffer = element._textBuffer
+      stateUpdate._scrollX = element._scrollX
+      stateUpdate._scrollY = element._scrollY
+      stateUpdate._scrollbarDragging = element._scrollbarDragging
+      stateUpdate._hoveredScrollbar = element._hoveredScrollbar
+      stateUpdate._scrollbarDragOffset = element._scrollbarDragOffset
+      stateUpdate._cursorBlinkTimer = element._cursorBlinkTimer
+      stateUpdate._cursorVisible = element._cursorVisible
+      stateUpdate._cursorBlinkPaused = element._cursorBlinkPaused
+      stateUpdate._cursorBlinkPauseTimer = element._cursorBlinkPauseTimer
+
+      -- Use optimized update that only changes modified values
+      StateManager.updateStateIfChanged(element.id, stateUpdate)
     end
   end
 

modules/Blur.lua

@@ -4,16 +4,36 @@ local unpack = table.unpack or unpack
 local Cache = {
   canvases = {},
   quads = {},
+  blurInstances = {}, -- Cache blur instances by quality
   MAX_CANVAS_SIZE = 20,
   MAX_QUAD_SIZE = 20,
+  INTENSITY_THRESHOLD = 5, -- Skip blur below this intensity
 }
 
+--- Round canvas size to nearest bucket for better reuse
+---@param size number Size to bucket
+---@return number bucketSize Bucketed size
+local function bucketSize(size)
+  if size <= 128 then
+    return math.ceil(size / 32) * 32
+  elseif size <= 512 then
+    return math.ceil(size / 64) * 64
+  elseif size <= 1024 then
+    return math.ceil(size / 128) * 128
+  else
+    return math.ceil(size / 256) * 256
+  end
+end
+
 --- Get or create a canvas from cache
 ---@param width number Canvas width
 ---@param height number Canvas height
 ---@return love.Canvas canvas The cached or new canvas
 function Cache.getCanvas(width, height)
-  local key = string.format("%dx%d", width, height)
+  -- Use bucketed sizes for better cache reuse
+  local bucketedWidth = bucketSize(width)
+  local bucketedHeight = bucketSize(height)
+  local key = string.format("%dx%d", bucketedWidth, bucketedHeight)
 
   if not Cache.canvases[key] then
     Cache.canvases[key] = {}
@@ -28,11 +48,14 @@ function Cache.getCanvas(width, height)
     end
   end
 
-  local canvas = love.graphics.newCanvas(width, height)
+  local canvas = love.graphics.newCanvas(bucketedWidth, bucketedHeight)
   table.insert(cache, { canvas = canvas, inUse = true })
 
   if #cache > Cache.MAX_CANVAS_SIZE then
-    table.remove(cache, 1)
+    local removed = table.remove(cache, 1)
+    if removed and removed.canvas then
+      removed.canvas:release()
+    end
   end
 
   return canvas
@@ -102,6 +125,7 @@ end
 function Cache.clear()
   Cache.canvases = {}
   Cache.quads = {}
+  Cache.blurInstances = {}
 end
 
 -- ============================================================================
@@ -169,6 +193,27 @@ function ShaderBuilder.build(taps, offset, offsetType, sigma)
   return love.graphics.newShader(shaderCode)
 end
 
+--- Get or create a blur instance from cache
+---@param quality number Quality level (1-10)
+---@return table blurData Cached blur data {shader, taps}
+function Cache.getBlurInstance(quality)
+  if not Cache.blurInstances[quality] then
+    local taps = 3 + (quality - 1) * 1.5
+    taps = math.floor(taps)
+    if taps % 2 == 0 then
+      taps = taps + 1
+    end
+    
+    local shader = ShaderBuilder.build(taps, 1.0, "weighted", -1)
+    Cache.blurInstances[quality] = {
+      shader = shader,
+      taps = taps,
+    }
+  end
+  
+  return Cache.blurInstances[quality]
+end
+
 ---@class BlurProps
 ---@field quality number? Quality level (1-10, default: 5)
 
@@ -189,26 +234,13 @@ function Blur.new(props)
   local quality = props.quality or 5
   quality = math.max(1, math.min(10, quality))
 
-  -- Map quality to shader parameters
-  -- Quality 1: 3 taps (fastest, lowest quality)
-  -- Quality 5: 7 taps (balanced)
-  -- Quality 10: 15 taps (slowest, highest quality)
-  local taps = 3 + (quality - 1) * 1.5
-  taps = math.floor(taps)
-  if taps % 2 == 0 then
-    taps = taps + 1
-  end
-
-  local offset = 1.0
-  local offsetType = "weighted"
-  local sigma = -1
-
-  local shader = ShaderBuilder.build(taps, offset, offsetType, sigma)
+  -- Get cached blur instance for this quality level
+  local blurData = Cache.getBlurInstance(quality)
 
   local self = setmetatable({}, Blur)
-  self.shader = shader
+  self.shader = blurData.shader
   self.quality = quality
-  self.taps = taps
+  self.taps = blurData.taps
 
   return self
 end
@@ -233,6 +265,12 @@ function Blur:applyToRegion(intensity, x, y, width, height, drawFunc)
     return
   end
 
+  -- Early exit for very low intensity (optimization)
+  if intensity < Cache.INTENSITY_THRESHOLD then
+    drawFunc()
+    return
+  end
+
   intensity = math.max(0, math.min(100, intensity))
 
   -- Intensity 0-100 maps to 0-5 passes
@@ -302,6 +340,11 @@ function Blur:applyBackdrop(intensity, x, y, width, height, backdropCanvas)
     return
   end
 
+  -- Early exit for very low intensity (optimization)
+  if intensity < Cache.INTENSITY_THRESHOLD then
+    return
+  end
+
   intensity = math.max(0, math.min(100, intensity))
 
   local passes = math.ceil(intensity / 20)

modules/LayoutEngine.lua

@@ -99,6 +99,14 @@ function LayoutEngine.new(props, deps)
   self._layoutCount = 0
   self._lastFrameCount = 0
 
+  -- Layout memoization cache
+  self._layoutCache = {
+    childrenCount = 0,
+    containerWidth = 0,
+    containerHeight = 0,
+    childrenHash = "",
+  }
+
   return self
 end
 
@@ -169,6 +177,14 @@ function LayoutEngine:layoutChildren()
     return
   end
 
+  -- Check if layout can be skipped (memoization optimization)
+  if self:_canSkipLayout() then
+    if timerName and LayoutEngine._Performance then
+      LayoutEngine._Performance:stopTimer(timerName)
+    end
+    return
+  end
+
   -- Track layout recalculations for performance warnings
   self:_trackLayoutRecalculation()
 
@@ -987,6 +1003,44 @@ function LayoutEngine:recalculateUnits(newViewportWidth, newViewportHeight)
   end
 end
 
+--- Check if layout can be skipped based on cached state (memoization)
+---@return boolean canSkip True if layout hasn't changed and can be skipped
+function LayoutEngine:_canSkipLayout()
+  if not self.element then
+    return false
+  end
+
+  local childrenCount = #self.element.children
+  local containerWidth = self.element.width
+  local containerHeight = self.element.height
+
+  -- Generate simple hash of children dimensions
+  local childrenHash = ""
+  for i, child in ipairs(self.element.children) do
+    if i <= 5 then -- Only hash first 5 children for performance
+      childrenHash = childrenHash .. child.width .. "x" .. child.height .. ","
+    end
+  end
+
+  local cache = self._layoutCache
+  
+  -- Check if layout inputs have changed
+  if cache.childrenCount == childrenCount and
+     cache.containerWidth == containerWidth and
+     cache.containerHeight == containerHeight and
+     cache.childrenHash == childrenHash then
+    return true -- Layout hasn't changed, can skip
+  end
+
+  -- Update cache with current values
+  cache.childrenCount = childrenCount
+  cache.containerWidth = containerWidth
+  cache.containerHeight = containerHeight
+  cache.childrenHash = childrenHash
+
+  return false -- Layout has changed, must recalculate
+end
+
 --- Track layout recalculations and warn about excessive layouts
 function LayoutEngine:_trackLayoutRecalculation()
   if not LayoutEngine._Performance or not LayoutEngine._Performance.warningsEnabled then

modules/StateManager.lua

@@ -340,13 +340,42 @@ end
 function StateManager.updateState(id, newState)
   local state = StateManager.getState(id)
 
-  -- Merge new state into existing state
+  -- Merge new state into existing state (with diffing optimization)
+  local changed = false
   for key, value in pairs(newState) do
+    if state[key] ~= value then
       state[key] = value
+      changed = true
+    end
   end
 
-  -- Update metadata
+  -- Only update metadata if something actually changed
+  if changed then
     stateMetadata[id].lastFrame = frameNumber
+  end
+end
+
+--- Update state only if values have changed (optimized for immediate mode)
+---@param id string Element ID
+---@param newState table New state values to merge
+---@return boolean changed True if any values changed
+function StateManager.updateStateIfChanged(id, newState)
+  local state = StateManager.getState(id)
+  local changed = false
+
+  for key, value in pairs(newState) do
+    -- Skip if value hasn't changed (optimization)
+    if state[key] ~= value then
+      state[key] = value
+      changed = true
+    end
+  end
+
+  if changed then
+    stateMetadata[id].lastFrame = frameNumber
+  end
+
+  return changed
 end
 
 --- Clear state for a specific element ID

modules/utils.lua

@@ -193,8 +193,17 @@ end
 ---@param fontPath string?
 ---@return love.Font
 function FONT_CACHE.get(size, fontPath)
-  -- Round size to reduce cache entries (e.g., 14.5 -> 15, 14.7 -> 15)
-  size = math.floor(size + 0.5)
+  -- Bucket font sizes for better cache reuse (reduces unique cache entries)
+  -- Small sizes (< 20): round to nearest 2
+  -- Medium sizes (20-40): round to nearest 4
+  -- Large sizes (> 40): round to nearest 8
+  if size < 20 then
+    size = math.floor((size + 1) / 2) * 2
+  elseif size < 40 then
+    size = math.floor((size + 2) / 4) * 4
+  else
+    size = math.floor((size + 4) / 8) * 8
+  end
 
   local cacheKey = fontPath and (fontPath .. ":" .. tostring(size)) or ("default:" .. tostring(size))