include/basegfx/tools/lerp.hxx

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  19
  20 #ifndef INCLUDED_BASEGFX_TOOLS_LERP_HXX
  21 #define INCLUDED_BASEGFX_TOOLS_LERP_HXX
  22
  23 #include <sal/types.h>
  24
  25 namespace basegfx
  26 {
  27     namespace tools
  28     {
  29         /** Generic linear interpolator
  30
  31             @tpl ValueType
  32             Must have operator+ and operator* defined, and should
  33             have value semantics.
  34
  35             @param t
  36             As usual, t must be in the [0,1] range
  37         */
  38         template< typename ValueType > ValueType lerp( const ValueType&     rFrom,
  39                                                        const ValueType&     rTo,
  40                                                        double               t )
  41         {
  42             // This is only to suppress a double->int warning. All other
  43             // types should be okay here.
  44             return static_cast<ValueType>( (1.0-t)*rFrom + t*rTo );
  45         }
  46     }
  47 }
  48
  49 #endif // INCLUDED_BASEGFX_TOOLS_LERP_HXX
  50
  51 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */