Changeset 4525:07dfa64029bc in roaraudio

Timestamp:

10/16/10 22:33:14 (14 years ago)

Author:

phi

Branch:

default

Phase:

public

Message:

added generic float handling

Files:

• include/libroar/roarfloat.h (modified) (1 diff)
• libroar/roarfloat.c (modified) (1 diff)

include/libroar/roarfloat.h

@@ -39 +39 @@
 #include "libroar.h"
 
+typedef uint32_t roarfloat32;
+
+#define ROAR_UFLOAT32_MAX  65535
+
+#define ROAR_UFLOAT32_ZERO ROAR_HOST2NET32(0x00000000);
+#define ROAR_UFLOAT32_PINF ROAR_HOST2NET32(0x00000001);
+#define ROAR_UFLOAT32_NINF ROAR_HOST2NET32(0x0000FFFF);
+#define ROAR_UFLOAT32_PNAN ROAR_HOST2NET32(0x00007FFF);
+#define ROAR_UFLOAT32_NNAN ROAR_HOST2NET32(0x00008000);
+
+roarfloat32 roar_ufloat32_build(const uint16_t mul, const uint16_t scale);
+uint16_t roar_ufloat32_scale(const roarfloat32 f);
+uint16_t roar_ufloat32_mul(const roarfloat32 f);
+
+roarfloat32 roar_ufloat32_from_float(const float       f);
+float       roar_ufloat32_to_float  (const roarfloat32 f);
+
+int roar_float32_iszero(const roarfloat32 f);
+int roar_float32_isinf(const roarfloat32 f);
+int roar_float32_isnan(const roarfloat32 f);
+
 #endif
 

libroar/roarfloat.c

@@ -36 +36 @@
 #include "libroar.h"
 
+#ifdef ROAR_HAVE_LIBM
+#include <math.h>
+#endif
+
+union c4f {
+ unsigned char c[4];
+ roarfloat32 f;
+};
+
+roarfloat32 roar_ufloat32_build(const uint16_t mul, const uint16_t scale) {
+ union c4f ret;
+
+ ROAR_DBG("roar_ufloat32_build(mul=%u, scale=%u) = ?", (unsigned int)mul, (unsigned int)scale);
+
+ ret.c[0] = (scale & 0xFF00) >> 8;
+ ret.c[1] = (scale & 0x00FF) >> 0;
+ ret.c[2] = (mul   & 0xFF00) >> 8;
+ ret.c[3] = (mul   & 0x00FF) >> 0;
+
+ return ret.f;
+}
+
+uint16_t roar_ufloat32_scale(const roarfloat32 f) {
+ const union c4f p = {.f = f};
+
+ ROAR_DBG("roar_ufloat32_scale(f=?): p.c[] = {%u, %u, %u, %u}", (unsigned int)p.c[0], (unsigned int)p.c[1], (unsigned int)p.c[2], (unsigned int)p.c[3]);
+
+ return (p.c[0] << 8) | p.c[1];
+}
+
+uint16_t roar_ufloat32_mul(const roarfloat32 f) {
+ const union c4f p = {.f = f};
+
+ return (p.c[2] << 8) | p.c[3];
+}
+
+roarfloat32 roar_ufloat32_from_float(const float       f) {
+ uint16_t scale;
+
+ if ( f < 0 )
+  return ROAR_UFLOAT32_NNAN;
+
+ if ( f == 0 )
+  return ROAR_UFLOAT32_ZERO;
+
+ if ( f > ROAR_UFLOAT32_MAX )
+  return ROAR_UFLOAT32_PINF;
+
+ if ( f <= 1 ) {
+  scale = ROAR_UFLOAT32_MAX;
+ } else {
+  scale = (float)ROAR_UFLOAT32_MAX/f;
+ }
+
+ ROAR_DBG("roar_ufloat32_from_float(f=%f): scale=%u", f, (unsigned int)scale);
+
+ return roar_ufloat32_build(f*(float)scale, scale);
+}
+
+float       roar_ufloat32_to_float  (const roarfloat32 f) {
+ float mul   = roar_ufloat32_mul(f);
+ float scale = roar_ufloat32_scale(f);
+
+ ROAR_DBG("roar_ufloat32_to_float(f=?): mul=%f, scale=%f", mul, scale);
+
+ if ( roar_float32_iszero(f) )
+  return 0;
+
+#ifdef ROAR_HAVE_LIBM
+ if ( roar_float32_isinf(f) )
+  return INFINITY;
+
+ if ( roar_float32_isnan(f) )
+  return NAN;
+#endif
+
+ return mul/scale;
+}
+
+int roar_float32_iszero(const roarfloat32 f) {
+ const union c4f p = {.f = f};
+
+ return p.c[2] == 0 && p.c[3] == 0;
+}
+
+int roar_float32_isinf(const roarfloat32 f) {
+ const union c4f p = {.f = f};
+
+ if ( p.c[0] != 0 || p.c[1] != 0 )
+  return 0;
+
+ if ( p.c[2] == 0x00 && p.c[3] == 0x01 ) {
+  return  1;
+ } else if ( p.c[2] == 0xFF && p.c[3] == 0xFF ) {
+  return -1;
+ } else {
+  return 0;
+ }
+}
+
+int roar_float32_isnan(const roarfloat32 f) {
+ const union c4f p = {.f = f};
+
+ if ( p.c[0] != 0 || p.c[1] != 0 )
+  return 0;
+
+ if ( p.c[2] == 0x7F && p.c[3] == 0xFF ) {
+  return  1;
+ } else if ( p.c[2] == 0x80 && p.c[3] == 0x00 ) {
+  return -1;
+ } else {
+  return 0;
+ }
+}
+
 //ll