diff options
Diffstat (limited to 'basegfx/source/numeric/ftools.cxx')
| -rw-r--r-- | basegfx/source/numeric/ftools.cxx | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/basegfx/source/numeric/ftools.cxx b/basegfx/source/numeric/ftools.cxx index 0c9a1734ec50..1cbbe5cc2136 100644 --- a/basegfx/source/numeric/ftools.cxx +++ b/basegfx/source/numeric/ftools.cxx @@ -18,11 +18,88 @@ */ #include <basegfx/numeric/ftools.hxx> +#include <algorithm> namespace basegfx { // init static member of class fTools double ::basegfx::fTools::mfSmallValue = 0.000000001; + + double snapToNearestMultiple(double v, const double fStep) + { + if(fTools::equalZero(fStep)) + { + // with a zero step, all snaps to 0.0 + return 0.0; + } + else + { + const double fHalfStep(fStep * 0.5); + const double fChange(fHalfStep - fmod(v + fHalfStep, fStep)); + + if(basegfx::fTools::equal(fabs(v), fabs(fChange))) + { + return 0.0; + } + else + { + return v + fChange; + } + } + } + + double snapToZeroRange(double v, double fWidth) + { + if(fTools::equalZero(fWidth)) + { + // with no range all snaps to range bound + return 0.0; + } + else + { + if(v < 0.0 || v > fWidth) + { + double fRetval(fmod(v, fWidth)); + + if(fRetval < 0.0) + { + fRetval += fWidth; + } + + return fRetval; + } + else + { + return v; + } + } + } + + double snapToRange(double v, double fLow, double fHigh) + { + if(fTools::equal(fLow, fHigh)) + { + // with no range all snaps to range bound + return 0.0; + } + else + { + if(fLow > fHigh) + { + // correct range order. Evtl. assert this (?) + std::swap(fLow, fHigh); + } + + if(v < fLow || v > fHigh) + { + return snapToZeroRange(v - fLow, fHigh - fLow) + fLow; + } + else + { + return v; + } + } + } } // end of namespace basegfx /* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |