[fixpt] Make fixed point methods static inline and generic

Move the fixed point methods to static inline versions in
cairo-fixed-private.h, and don't hardcode fixed to be 16.16.

1 files changed, 1 insertions, 99 deletions

diff --git a/src/cairo-fixed.c b/src/cairo-fixed.c
index fe6c2dc3e..2bb0dfe17 100644
--- a/src/cairo-fixed.c
+++ b/src/cairo-fixed.c
@@ -36,102 +36,4 @@
 
 #include "cairoint.h"
 
-cairo_fixed_t
-_cairo_fixed_from_int (int i)
-{
-    return i << 16;
-}
-
-/* This is the "magic number" approach to converting a double into fixed
- * point as described here:
- *
- * http://www.stereopsis.com/sree/fpu2006.html (an overview)
- * http://www.d6.com/users/checker/pdfs/gdmfp.pdf (in detail)
- *
- * The basic idea is to add a large enough number to the double that the
- * literal floating point is moved up to the extent that it forces the
- * double's value to be shifted down to the bottom of the mantissa (to make
- * room for the large number being added in). Since the mantissa is, at a
- * given moment in time, a fixed point integer itself, one can convert a
- * float to various fixed point representations by moving around the point
- * of a floating point number through arithmetic operations. This behavior
- * is reliable on most modern platforms as it is mandated by the IEEE-754
- * standard for floating point arithmetic.
- *
- * For our purposes, a "magic number" must be carefully selected that is
- * both large enough to produce the desired point-shifting effect, and also
- * has no lower bits in its representation that would interfere with our
- * value at the bottom of the mantissa. The magic number is calculated as
- * follows:
- *
- *          (2 ^ (MANTISSA_SIZE - FRACTIONAL_SIZE)) * 1.5
- *
- * where in our case:
- *  - MANTISSA_SIZE for 64-bit doubles is 52
- *  - FRACTIONAL_SIZE for 16.16 fixed point is 16
- *
- * Although this approach provides a very large speedup of this function
- * on a wide-array of systems, it does come with two caveats:
- *
- * 1) It uses banker's rounding as opposed to arithmetic rounding.
- * 2) It doesn't function properly if the FPU is in single-precision
- *    mode.
- */
-#define CAIRO_MAGIC_NUMBER_FIXED_16_16 (103079215104.0)
-cairo_fixed_t
-_cairo_fixed_from_double (double d)
-{
-    union {
-        double d;
-        int32_t i[2];
-    } u;
-
-    u.d = d + CAIRO_MAGIC_NUMBER_FIXED_16_16;
-#ifdef FLOAT_WORDS_BIGENDIAN
-    return u.i[1];
-#else
-    return u.i[0];
-#endif
-}
-
-cairo_fixed_t
-_cairo_fixed_from_26_6 (uint32_t i)
-{
-    return i << 10;
-}
-
-double
-_cairo_fixed_to_double (cairo_fixed_t f)
-{
-    return ((double) f) / 65536.0;
-}
-
-int
-_cairo_fixed_is_integer (cairo_fixed_t f)
-{
-    return (f & 0xFFFF) == 0;
-}
-
-int
-_cairo_fixed_integer_part (cairo_fixed_t f)
-{
-    return f >> 16;
-}
-
-int
-_cairo_fixed_integer_floor (cairo_fixed_t f)
-{
-    if (f >= 0)
-	return f >> 16;
-    else
-	return -((-f - 1) >> 16) - 1;
-}
-
-int
-_cairo_fixed_integer_ceil (cairo_fixed_t f)
-{
-    if (f > 0)
-	return ((f - 1)>>16) + 1;
-    else
-	return - (-f >> 16);
-}
+#include "cairo-fixed-private.h"