slideshow/source/inc/lerp.hxx

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  30
  31 #ifndef INCLUDED_SLIDESHOW_LERP_HXX
  32 #define INCLUDED_SLIDESHOW_LERP_HXX
  33
  34 #include <sal/types.h>
  35
  36 namespace slideshow
  37 {
  38     namespace internal
  39     {
  40
  41         /** Generic linear interpolator
  42
  43             @tpl ValueType
  44             Must have operator+ and operator* defined, and should
  45             have value semantics.
  46
  47             @param t
  48             As usual, t must be in the [0,1] range
  49         */
  50         template< typename ValueType > ValueType lerp( const ValueType&         rFrom,
  51                                                        const ValueType&         rTo,
  52                                                        double                           t )
  53         {
  54             // This is only to suppress a double->int warning. All other
  55             // types should be okay here.
  56             return static_cast<ValueType>( (1.0-t)*rFrom + t*rTo );
  57         }
  58
  59     }
  60 }
  61
  62 #endif /* INCLUDED_SLIDESHOW_LERP_HXX */