From 6244999b080a68abcf7ee2d54a425eb776580cc9 Mon Sep 17 00:00:00 2001
From: Lauchmelder <robert.altner11@gmail.com>
Date: Sat, 16 Apr 2022 14:00:43 +0200
Subject: [PATCH] implemented poor timing

---
 Makefile   | 4 ++--
 src/main.c | 9 ++++++++-
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/Makefile b/Makefile
index ab3e48b..2d0ab7d 100644
--- a/Makefile
+++ b/Makefile
@@ -8,14 +8,14 @@ OBJS := $(patsubst src/%.c, out/%.o, $(SRCS))
 
 ALL: $(TARGET)
 
-$(TARGET): mkdir $(OBJS)
+$(TARGET): mkdir $(OBJS) 
 	$(CC) -o out/$@ $(filter-out $<, $^) $(LIBRARIES)
 
 mkdir:
 	mkdir -p out
 
 out/%.o: src/%.c
-	$(CC) $(CFLAGS) -c $< -o $@
+	$(CC) $(CFLAGS) -o $@ -c $< 
 
 clean:
 	rm -rf $(TARGET) out
diff --git a/src/main.c b/src/main.c
index 0aeeba7..e7096b9 100644
--- a/src/main.c
+++ b/src/main.c
@@ -69,11 +69,18 @@ int main(int argc, char** argv)
 void* advance_counter(void* data)
 {
     uint16_t ticks_per_quarter = *((uint32_t*)data);
+    struct timespec begin, end;
     while(!playing);
 
+    clock_gettime(CLOCK_REALTIME, &begin);
     for(;;)
     {
-        usleep((uint64_t)time_per_quarter / ticks_per_quarter);
+        clock_gettime(CLOCK_REALTIME, &end);
+        uint64_t diff = 1000000 * (end.tv_sec - begin.tv_sec) + (end.tv_nsec - begin.tv_nsec) / 1000;
+        diff -= (uint64_t)time_per_quarter / ticks_per_quarter;
+        diff *= (diff < (uint64_t)time_per_quarter / ticks_per_quarter);
+        clock_gettime(CLOCK_REALTIME, &begin);
+        usleep((uint64_t)time_per_quarter / ticks_per_quarter - diff);
         current_tick++;
     }
 }