X-Git-Url: https://git.sesse.net/?p=c64tapwav;a=blobdiff_plain;f=interpolate.h;h=c71110b37d71950c9b02b47950ff8d7c1d93bcac;hp=55bc61cc3ca146147e0ba31b68c303e8b387493f;hb=63deff31a441647619080ca046d1aa1c8edcea9e;hpb=08089f496815d725c3bee171bae0e884642ffc05

diff --git a/interpolate.h b/interpolate.h
index 55bc61c..c71110b 100644
--- a/interpolate.h
+++ b/interpolate.h
@@ -26,13 +26,13 @@ inline double lanczos_weight(double x)
 	return sinc(M_PI * x) * sinc(M_PI * x / LANCZOS_RADIUS);
 }
 
-extern double lanczos_table[(LANCZOS_RADIUS * 2) * LANCZOS_RESOLUTION];
+extern double lanczos_table[LANCZOS_RADIUS * LANCZOS_RESOLUTION];
 void make_lanczos_weight_table();
 
-inline double lanczos_weight_table(double x)
+inline double lanczos_weight_table(float x)
 {
-	int table_id = lrintf((x + LANCZOS_RADIUS) * LANCZOS_RESOLUTION);
-	if (table_id < 0 || table_id >= (LANCZOS_RADIUS * 2) * LANCZOS_RESOLUTION) {
+	int table_id = lrintf(fabsf(x) * LANCZOS_RESOLUTION);
+	if (table_id >= LANCZOS_RADIUS * LANCZOS_RESOLUTION) {
 		return 0.0;
 	}
 	return lanczos_table[table_id];