Add bpm_change_indicator.lua

bpm_change_indicator.lua

@@ -0,0 +1,91 @@
+local t = {}
+
+local function round(x)
+    return math.floor(x + 0.5)
+end
+
+local so = GAMESTATE:GetSongOptionsObject("ModsLevel_Song")
+
+local function get_rate()
+    return so:MusicRate()
+end
+
+local function compute_bpm()
+    local mpn = GAMESTATE:GetMasterPlayerNumber()
+    if not mpn then return nil end
+
+    local player_state = GAMESTATE:GetPlayerState(mpn)
+    if not player_state then return nil end
+
+    local sp = player_state:GetSongPosition()
+    if not sp then return nil end
+
+    local rate = get_rate()
+    return round(sp:GetCurBPS() * 60 * rate)
+end
+
+t["ScreenGameplay"] = Def.ActorFrame {
+    Name="BPMChangeHighlight",
+
+    InitCommand=function(self)
+        -- Roughly matches the default BPM display placement from Simply Love
+        self:xy(_screen.cx, 52):valign(1):zoom(1.33)
+
+        local mpn = GAMESTATE:GetMasterPlayerNumber()
+        if mpn == PLAYER_2 then
+            self:x(_screen.w - self:GetX())
+        end
+    end,
+
+    ModuleCommand=function(self)
+        self.prev_bpm = compute_bpm()
+
+        self:SetUpdateFunction(function(actor)
+            local bpm = compute_bpm()
+            if bpm ~= nil and actor.prev_bpm ~= nil then
+                if bpm > actor.prev_bpm then
+                    actor:GetChild("FlashPanel"):playcommand("FlashGreen")
+                elseif bpm < actor.prev_bpm then
+                    actor:GetChild("FlashPanel"):playcommand("FlashRed")
+                end
+            end
+            actor.prev_bpm = bpm
+        end)
+    end,
+
+    Def.Quad{
+        Name="FlashPanel",
+        InitCommand=function(self)
+            -- Should be big enough to be noticeable, but not obnoxious (hopefully)
+            self:zoomto(100, 30):diffusealpha(0)
+        end,
+        FlashGreenCommand=function(self)
+            self:finishtweening():diffuse(color("0,1,0,1")):diffusealpha(0.6):linear(1):diffusealpha(0)
+        end,
+        FlashRedCommand=function(self)
+            self:finishtweening():diffuse(color("1,0,0,1")):diffusealpha(0.6):linear(1):diffusealpha(0)
+        end,
+    }
+}
+
+return t
+
+-- Copyright (c) 2025 sukibaby
+
+-- Permission is hereby granted, free of charge, to any person obtaining a copy
+-- of this software and associated documentation files (the "Software"), to deal
+-- in the Software without restriction, including without limitation the rights
+-- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+-- copies of the Software, and to permit persons to whom the Software is
+-- furnished to do so, subject to the following conditions:
+
+-- The above copyright notice and this permission notice shall be included in all
+-- copies or substantial portions of the Software.
+
+-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+-- SOFTWARE.