Merge pull request #23 from gheskett/better-reverb

Redocument some reverb parameters and adjust default values

src/audio/synthesis.c

@@ -37,7 +37,8 @@
 
 #define AUDIO_ALIGN(val, amnt) (((val) + (1 << amnt) - 1) & ~((1 << amnt) - 1))
 
-/* -------------------------------------------------------BEGIN REVERB PARAMETERS-------------------------------------------------------------- */
+/* ----------------------------------------------------------------------BEGIN REVERB PARAMETERS---------------------------------------------------------------------- */
+
 
 /**
  * This reverb is a much more natural, ambient implementation over vanilla's, though at the cost of some memory and performance.
@@ -48,18 +49,36 @@
  * To use with M64 sequences, set the Effect parameter for each channel accordingly (CC 91 for MIDI files).
  */
 
-s32 gReverbRevIndex = 0x7F; // Affects decay time mostly; can be messed with at any time (and also probably the most useful parameter here)
-s32 gReverbGainIndex = 0xA3; // Affects signal immediately retransmitted back into buffers; can be messed with at any time
-s32 gReverbWetSignal = 0xEF; // Amount of reverb specific output in final signal; can be messed with at any time
+
+// Setting this to 4 corrupts the game, so set this value to -1 to use vanilla reverb if this is too slow, or if it just doesn't fit the desired aesthetic of a level.
+// You can change this value before audio_reset_session gets called if different levels can tolerate the demand better than others or just have different reverb goals.
+// A higher downsample value hits the game's frequency limit sooner, which can cause the reverb sometimes to be off pitch. This is a vanilla level issue (and also counter intuitive).
+// Higher downsample values also result in slightly shorter reverb decay times.
+s8 betterReverbConsoleDownsample = 3;
+
+// Most emulators can handle a default value of 2, but 3 may be advisable in some cases if targeting older emulators (e.g. PJ64 1.6). Setting this to -1 also uses vanilla reverb.
+// Using a value of 1 is not recommended except in very specific situations. If you do decide to use 1 here, you must adjust BETTER_REVERB_SIZE appropriately.
+// You can change this value before audio_reset_session gets called if different levels can tolerate the demand better than others or just have different reverb goals.
+// A higher downsample value hits the game's frequency limit sooner, which can cause the reverb sometimes to be off pitch. This is a vanilla level issue (and also counter intuitive).
+// Higher downsample values also result in slightly shorter reverb decay times.
+s8 betterReverbEmulatorDownsample = 2;
+
+s32 gReverbRevIndex = 0x5F; // Affects decay time mostly (large values can cause terrible feedback!); can be messed with at any time
+s32 gReverbGainIndex = 0x9F; // Affects signal immediately retransmitted back into buffers (mid-high values yield the strongest effect); can be messed with at any time
+s32 gReverbWetSignal = 0xE7; // Amount of reverb specific output in final signal (also affects decay); can be messed with at any time, also very easy to control
 s32 gReverbDrySignal = 0x00; // Amount of original input in final signal (large values can cause terrible feedback!); can be messed with at any time
 
-// This value controls the size of the reverb buffer. It affects the global reverb delay time. This is probably the easiest parameter to control usefully.
+// This value controls the size of the reverb buffer. It affects the global reverb delay time. This variable is one of the easiest to control.
 // It is not recommended setting this to values greater than 0x1000 * 2^(downsample factor - 1), as you run the risk of running into a memory issue (though this is far from a guarantee).
-// Setting the value lower than the downsample buffer size will destroy the game audio, so this is taken into account automatically but may limit the lower possibilities.
+// Setting the value lower than the downsample buffer size will destroy the game audio. This is taken into account automatically, but also means the value set here isn't what always gets used.
 // If this value is changed, it will go into effect the next time audio_reset_session is called.
 // Set to -1 to use a default preset instead. Higher values represent more audio delay (usually better for echoey spaces).
 s32 betterReverbWindowsSize = -1;
 
+
+/* ---------------------------------------------------------------------ADVANCED REVERB PARAMETERS-------------------------------------------------------------------- */
+
+
 // These values affect filter delays. Bigger values will result in fatter echo (and more memory); must be cumulatively smaller than BETTER_REVERB_SIZE/4.
 // If setting a reverb downsample value to 1, this must be smaller than BETTER_REVERB_SIZE/8.
 // These values should never be changed unless in this declaration or during a call to audio_reset_session, as it could otherwise lead to a major memory leak or garbage audio.
@@ -88,20 +107,8 @@ const s32 reverbMults[2][NUM_ALLPASS / 3] = {
     {0x38, 0x26, 0xCF, 0x71} // Right Channel
 };
 
-// Setting this to 4 corrupts the game, so set this value to -1 to use vanilla reverb if this is too slow, or if it just doesn't fit the desired aesthetic of a level.
-// You can change this value before audio_reset_session gets called if different levels can tolerate the demand better than others or just have different reverb goals.
-// A higher downsample value hits the game's frequency limit sooner, which can cause the reverb sometimes to be off pitch. This is a vanilla level issue (and also counter intuitive).
-// Higher downsample values also result in slightly shorter reverb decay times.
-s8 betterReverbConsoleDownsample = 3;
 
-// Most emulators can handle a default value of 2, but 3 may be advisable in some cases if targeting older emulators (e.g. PJ64 1.6). Setting this to -1 also uses vanilla reverb.
-// Using a value of 1 is not recommended except in very specific situations. If you do decide to use 1 here, you must adjust BETTER_REVERB_SIZE appropriately.
-// You can change this value before audio_reset_session gets called if different levels can tolerate the demand better than others or just have different reverb goals.
-// A higher downsample value hits the game's frequency limit sooner, which can cause the reverb sometimes to be off pitch. This is a vanilla level issue (and also counter intuitive).
-// Higher downsample values also result in slightly shorter reverb decay times.
-s8 betterReverbEmulatorDownsample = 2;
-
-/* --------------------------------------------------------END REVERB PARAMETERS--------------------------------------------------------------- */
+/* -----------------------------------------------------------------------END REVERB PARAMETERS----------------------------------------------------------------------- */
 
 // Do not touch these values.
 u8 toggleBetterReverb = TRUE;