G2 support

src/core/ChipAudio.lua

@@ -113,6 +113,8 @@ local function slimAudio(data)
     bankOrder = audio.bankOrder,
     waveBanks = audio.waveBanks,
     noiseHeaders = audio.noiseHeaders,
+    generation = audio.generation,
+    drumkits = audio.drumkits,
   }
 end
 
@@ -435,13 +437,18 @@ end
 -- a mono Source is spatialized by OpenAL at the listener position and spreads
 -- over every output an interface has (#626).  The siren itself is unchanged,
 -- both channels carry the same sample.
+-- PlayDanger (audio/engine.asm:531) counts one frame per call and resets with
+-- `cp 30 / jr c, .noreset`, so the cycle is frames 0..29 and the buffer holds
+-- exactly two of them.  DangerSoundHigh goes in on the `and a / jr z, .begin`
+-- frame 0 and DangerSoundLow on the `cp 16 / jr z, .halfway` frame 16, so the
+-- high tone owns 0..15 and the low tone 16..29.
 function ChipAudio.newLowHealthAlarm()
-  local samples = math.floor(SAMPLE_RATE * 62 / 60)
+  local samples = math.floor(SAMPLE_RATE * 60 / 60)
   local data = love.sound.newSoundData(samples, SAMPLE_RATE, 16, 2)
   local phase = 0
   for index = 0, samples - 1 do
-    local frame = math.floor(index * 60 / SAMPLE_RATE) % 31
-    local register = frame < 11 and 0x750 or 0x6EE
+    local frame = math.floor(index * 60 / SAMPLE_RATE) % 30
+    local register = frame < 16 and 0x750 or 0x6EE
     local frequency = 131072 / (2048 - register)
     phase = (phase + frequency / SAMPLE_RATE) % 1
     local value = (phase < 0.5 and 1 or -1) * 0.25