Updated fix16_atan, now removes some un-necessary code.

Added FIXMATH_NO_ROUNDING macro to disable rounding, currently only applies to fix16_atan but will change to apply this to other operations (namely mul/div) too.
Changed optimization options for rel build in code::blocks project.

2 files changed, 17 insertions, 11 deletions

diff --git a/libfixmath/fix16_trig.c b/libfixmath/fix16_trig.c
index 2e0ec5a..6533a52 100644
--- a/libfixmath/fix16_trig.c
+++ b/libfixmath/fix16_trig.c
@@ -87,9 +87,14 @@ fix16_t fix16_atan2(fix16_t inY , fix16_t inX) {
 	int64_t angle;

 	angle  = (4216574283LL * -i) / j;

 	is = (i * i);

-	is = (is + (1LL << 15)) >> 16;

 	js = (j * j);

+	#ifdef FIXMATH_NO_ROUNDING

+	is >>= 16;

+	js >>= 16;

+	#else

+	is = (is + (1LL << 15)) >> 16;

 	js = (js + (1LL << 15)) >> 16;

+	#endif

 	if((is | js) >> 32) {

 		if((is | js) >> 40) {

 			is >>= 16;

@@ -100,22 +105,22 @@ fix16_t fix16_atan2(fix16_t inY , fix16_t inX) {
 		}

 	}

 	is = (is * i);

-	is = (is + (1LL << 15)) >> 16;

 	js = (js * j);

+	#ifdef FIXMATH_NO_ROUNDING

+	is >>= 16;

+	js >>= 16;

+	#else

+	is = (is + (1LL << 15)) >> 16;

 	js = (js + (1LL << 15)) >> 16;

-	if((is | js) >> 50) {

-		if((is | js) >> 57) {

-			is >>= 14;

-			js >>= 14;

-		} else {

-			is >>= 7;

-			js >>= 7;

-		}

-	}

+	#endif

 	is = is * 51472LL;

 	angle += (is / js) << 14;

 	angle += (inX >= 0 ? 3373259426LL : 10119778278LL);

+	#ifdef FIXMATH_NO_ROUNDING

+	angle >>= 16;

+	#else

 	angle = (angle + (1LL << 15)) >> 16;

+	#endif

 	angle = (inY < 0 ? -angle : angle);

 

 	#ifndef FIXMATH_NO_CACHE

diff --git a/libfixmath/libfixmath.cbp b/libfixmath/libfixmath.cbp
index c88b66b..d9264ea 100644
--- a/libfixmath/libfixmath.cbp
+++ b/libfixmath/libfixmath.cbp
@@ -16,6 +16,7 @@
 				<Compiler>
 					<Add option="-Wall" />
 					<Add option="-g" />
+					<Add option="-DFIXMATH_NO_CACHE" />
 				</Compiler>
 			</Target>
 			<Target title="rel">