From e00d98708316182096e217a975e212c33afec837 Mon Sep 17 00:00:00 2001
From: Sam Hocevar <sam@hocevar.net>
Date: Wed, 2 Jan 2013 12:53:39 +0000
Subject: [PATCH] math: implement fract() for vectors and scalar types.

---
 src/lol/math/half.h   |  1 +
 src/lol/math/math.h   | 15 +++++++++++++++
 src/lol/math/vector.h | 32 +++++++++++++++++++++++++++++++-
 3 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/src/lol/math/half.h b/src/lol/math/half.h
index 65a93fe8..b554e190 100644
--- a/src/lol/math/half.h
+++ b/src/lol/math/half.h
@@ -125,6 +125,7 @@ static inline half fmod(half a, half b)
     using std::fmod;
     return (half)fmod((float)a, (float)b);
 }
+static inline half fract(half a) { return (half)fract((float)a); }
 static inline half abs(half a) { return half::makebits(a.bits & 0x7fffu); }
 
 static inline half clamp(half x, half a, half b)
diff --git a/src/lol/math/math.h b/src/lol/math/math.h
index 3e0836c5..24b01ed8 100644
--- a/src/lol/math/math.h
+++ b/src/lol/math/math.h
@@ -33,6 +33,9 @@ namespace lol
 static inline double sqrt(double const &x) { return std::sqrt(x); }
 static inline float sqrt(float const &x) { return std::sqrt(x); }
 
+static inline double exp(double const &x) { return std::exp(x); }
+static inline float exp(float const &x) { return std::exp(x); }
+
 static inline double sin(double const &x) { return std::sin(x); }
 static inline double cos(double const &x) { return std::cos(x); }
 static inline double tan(double const &x) { return std::tan(x); }
@@ -138,6 +141,18 @@ static inline float fmod(float x, float y) { return std::fmod(x, y); }
 static inline double fmod(double x, double y) { return std::fmod(x, y); }
 static inline ldouble fmod(ldouble x, ldouble y) { return std::fmod(x, y); }
 
+static inline uint8_t fract(uint8_t x) { return 0; }
+static inline int8_t fract(int8_t x) { return 0; }
+static inline uint16_t fract(uint16_t x) { return 0; }
+static inline int16_t fract(int16_t x) { return 0; }
+static inline uint32_t fract(uint32_t x) { return 0; }
+static inline int32_t fract(int32_t x) { return 0; }
+static inline uint64_t fract(uint64_t x) { return 0; }
+static inline int64_t fract(int64_t x) { return 0; }
+static inline float fract(float x) { return x - std::floor(x); }
+static inline double fract(double x) { return x - std::floor(x); }
+static inline ldouble fract(ldouble x) { return x - std::floor(x); }
+
 static inline uint8_t min(uint8_t x, uint8_t y) { return std::min(x, y); }
 static inline int8_t min(int8_t x, int8_t y) { return std::min(x, y); }
 static inline uint16_t min(uint16_t x, uint16_t y) { return std::min(x, y); }
diff --git a/src/lol/math/vector.h b/src/lol/math/vector.h
index c9fe9f84..cf8d4676 100644
--- a/src/lol/math/vector.h
+++ b/src/lol/math/vector.h
@@ -1134,6 +1134,25 @@ extern Quat<T> slerp(Quat<T> const &qa, Quat<T> const &qb, T f);
         return max(min(x, b), a); \
     }
 
+/*
+ * vec mix(vec, vec, vec)
+ * vec mix(vec, vec, scalar)
+ */
+#define LOL_VECTOR_MIX_FUN(tname, tprefix, type) \
+    tprefix \
+    inline tname<type> mix(tname<type> const &x, \
+                           tname<type> const &y, tname<type> const &a) \
+    { \
+        return x + a * (y - x); \
+    } \
+    \
+    tprefix \
+    inline tname<type> mix(tname<type> const &x, \
+                           tname<type> const &y, type const &a) \
+    { \
+        return x + a * (y - x); \
+    }
+
 /*
  * bool ==(vec, vec)   (also complex & quaternion)
  * bool !=(vec, vec)   (also complex & quaternion)
@@ -1218,6 +1237,15 @@ extern Quat<T> slerp(Quat<T> const &qa, Quat<T> const &qb, T f);
     } \
     \
     tprefix \
+    inline tname<type> fract(tname<type> const &a) \
+    { \
+        tname<type> ret; \
+        for (size_t n = 0; n < sizeof(a) / sizeof(type); n++) \
+            ret[n] = fract(a[n]); \
+        return ret; \
+    } \
+    \
+    tprefix \
     inline tname<type> normalize(tname<type> const &a) \
     { \
         type norm = (type)length(a); \
@@ -1293,7 +1321,8 @@ extern Quat<T> slerp(Quat<T> const &qa, Quat<T> const &qb, T f);
     LOL_VECTOR_MINMAX_FUN(tname, min, tprefix, type) \
     LOL_VECTOR_MINMAX_FUN(tname, max, tprefix, type) \
     LOL_VECTOR_MINMAX_FUN(tname, fmod, tprefix, type) \
-    LOL_VECTOR_CLAMP_FUN(tname, tprefix, type)
+    LOL_VECTOR_CLAMP_FUN(tname, tprefix, type) \
+    LOL_VECTOR_MIX_FUN(tname, tprefix, type)
 
 #define LOL_VECTOR_COERCE_OPS(tname, tprefix, t1, t2, tf) \
     LOL_VECTOR_VECTOR_COERCE_OP(tname, *, tprefix, t1, t2, tf) \
@@ -1563,6 +1592,7 @@ ACTIVATE_COERCE_NAMESPACES(real)
 #undef LOL_VECTOR_VECTOR_OP
 #undef LOL_VECTOR_MINMAX_FUN
 #undef LOL_VECTOR_CLAMP_FUN
+#undef LOL_VECTOR_MIX_FUN
 #undef LOL_VECTOR_VECTOR_BOOL_OP
 #undef LOL_VECTOR_SCALAR_COERCE_OP
 #undef LOL_SCALAR_VECTOR_COERCE_OP