Cleaup some leftover code and comments

1 files changed, 5 insertions, 0 deletions

diff --git a/src/common.h b/src/common.h
index 048708b..0fe2752 100644
--- a/src/common.h
+++ b/src/common.h
@@ -722,6 +722,11 @@ wait_vsync(void) {
 #define CLAMP(X, MIN, MAX) ((X) <= (MIN) ? (MIN) : (X) > (MAX) ? (MAX): (X))
 #define LEN(ARR) (sizeof(ARR) / sizeof((ARR)[0]))
 
+// Fixed-point arithmetic for (i.P) numbers.
+#define FP_MUL(A,B,P)      (((A) * (B)) >> (P))
+#define FP_DIV(A,B,P)      (((A) << (P)) / (B))
+#define FP_LERP(Y0,Y1,X,P) ((Y0) + FP_MUL((X), ((Y1) - (Y0)), P))
+
 //
 // Memory section macros for devkitARM.
 //