Synchronise the controller status more spread out inside a rendered frame:

* before rendering a background;
* before rendering sprites;
* while rendering more than 128 samples of audio at once ("Prefer fluid video");
* after every 16 scanlines of CPU execution instead of every 1;
* while waiting for an audio buffer to become available;
* while killing time between frames with fast-forward disabled.

Controller presses and releases are now combined in a DS button bitfield using a shorter 32-bit algorithm. See entry.cpp:NDSSFCAccumulateJoypad and #define ACCUMULATE_JOYPAD in the source.

This is still not suitable for playing platformers frame-perfectly, but it's much better than half a second of latency to press or release a button, and one still needs to press buttons a bit more than just light taps. I'd say 50 milliseconds is the latency now. Platformers requiring more precision can be played with frameskip 0.

DMA does not require double-buffered displaying, so synchronise the controller more often by disabling double-buffered displaying again.

1 files changed, 9 insertions, 0 deletions

diff --git a/source/soundux.cpp b/source/soundux.cpp
index dde8a14..c20f366 100644
--- a/source/soundux.cpp
+++ b/source/soundux.cpp
@@ -1233,6 +1233,15 @@ static inline void MixMono (int sample_count)
 		
 		for (uint32 I = 0; I < (uint32) sample_count; I++)
 		{
+#ifdef ACCUMULATE_JOYPAD
+/*
+ * This call allows NDSSFC to synchronise the DS controller more often.
+ * If porting a later version of Snes9x into NDSSFC, it is essential to
+ * preserve it.
+ */
+			if ((I & 0x7F) == 0x7F)
+				NDSSFCAccumulateJoypad ();
+#endif
 			unsigned long freq = freq0;
 			
 			if (mod)