This commit:
* Adds a 'compare_ff' function for absolute 'almost equal' comparison of floats.
* Makes 'compare_vxvx' functions use that new 'compare_ff' one.
* Adds a 'compare_ff_relative' function for secured ulp-based relative comparison of floats.
* Adds matching 'compare_vxvx_relative' functions.
* Adds some basic tests for compare_ff_relative.
See https://randomascii.wordpress.com/2012/02/25/comparing-floating-point-numbers-2012-edition/
Note that we could replace our python/mathutils' EXPP_FloatsAreEqual() by BLI's compare_ff_relative
(using a very small absolute max_diff), but these do not have exact same behavior...
Left a comment there for now, we can do it later if/when we are sure it won't break anything!
old issue, the formulas here were never quite right, should all work ok now
with byte and float images.
Some differences:
* Colors with zero alpha from the background will never have an influence, so
you don't get alpha fringes when painting over such areas. This does give
hard edges when looking at the RGB channels alone, but there's no way to
avoid that and fringes at the same time, same behavior as other painting apps.
* Add/Subtract/Multiply/Lighten/Darken now leave the alpha channel unchanged
and work only the RGB channels, again same behavior as many other apps.
* Erase/Add alpha now compensates for premultiplied float images to keep the
straight RGB colors the same.
Next: fix projection painting.
The problem was that vertex colors only have 8 bits of precision, and integer
division always rounds down, so after some color blending iterations everything
gets darker. Instead use integer division that behaves like round() instead of
floor() for blending operations.
* MEM_CacheLimitier - Size type to int conversion, should be safe for now (doing my best Bill Gates 640k impression)
* OpenNL CMakeLists.txt - MSVC and GCC have slightly different ways to remove definitions (DEBUG) without the compiler complaining
* BLI_math inlines - The include guard name and inline option macro name should be different. Suppressed warning about not exporting any symbols from inline math library
* BLI string / utf8 - Fixed some inconsistencies between declarations and definitions
* nodes - node_composite_util is apparently not used unless you enable the legacy compositor, so it should not be compiled in that case.
Leaving out changes to BLI_fileops for now, need to do more testing.
Basically two simple changes, changes, I pulled in the faster
ghash in bmesh (which uses mempools for allocation, providing
a substanstial speedup in some cases, and also I inlined some
of the functions), and I changed __inline to __forceinline for inlining
of math functions.
I also removed the timer in the view3d zoom op (ctrl-middlemouse)
that was making it nonfunctional. Why was that there?
* inline some more functions, from math_base and math_vector
* also made some changes to the way inline is done so it can
work for more than one file
* reflect_v3_v3v3 requires input vectors to be normalized now.
* added rgb_to_grayscale
* added zero_v4, copy_v4_v4, swap_v4_v4, is_one_v3
* added box_clip_bounds_m4 to clip a bounding box against a
projection matrix
