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authorTaybin Rutkin <taybin@taybin.com>2005-08-11 19:45:29 +0000
committerTaybin Rutkin <taybin@taybin.com>2005-08-11 19:45:29 +0000
commitf9546e5c76afa101e9dbe8a057e72463b03430e5 (patch)
treec8ff473dde0110d81b0076c0b68f2c218ffcb3be /libs
parent45866a0ab0ad66169f3e9ea111ede017a80fb3b5 (diff)
Synced fastlog.h with ardour1 updates.
git-svn-id: svn://localhost/trunk/ardour2@16 d708f5d6-7413-0410-9779-e7cbd77b26cf
Diffstat (limited to 'libs')
-rw-r--r--libs/pbd3/pbd/fastlog.h6
1 files changed, 4 insertions, 2 deletions
diff --git a/libs/pbd3/pbd/fastlog.h b/libs/pbd3/pbd/fastlog.h
index 4e9050cb8b..4269705a44 100644
--- a/libs/pbd3/pbd/fastlog.h
+++ b/libs/pbd3/pbd/fastlog.h
@@ -11,14 +11,16 @@ static inline float fast_log2 (float val)
/* don't use reinterpret_cast<> because that prevents this
from being used by pure C code (for example, GnomeCanvasItems)
*/
- int * const exp_ptr = (int *)(&val);
+ union {float f; int i;} t;
+ t.f = val;
+ int * const exp_ptr = &t.i;
int x = *exp_ptr;
const int log_2 = ((x >> 23) & 255) - 128;
x &= ~(255 << 23);
x += 127 << 23;
*exp_ptr = x;
- val = ((-1.0f/3) * val + 2) * val - 2.0f/3; // (1)
+ val = ((-1.0f/3) * t.f + 2) * t.f - 2.0f/3;
return (val + log_2);
}