1 /************************************************************** 2 * 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, 14 * software distributed under the License is distributed on an 15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16 * KIND, either express or implied. See the License for the 17 * specific language governing permissions and limitations 18 * under the License. 19 * 20 *************************************************************/ 21 22 23 24 #ifndef _BGFX_TOOLS_LERP_HXX 25 #define _BGFX_TOOLS_LERP_HXX 26 27 #include <sal/types.h> 28 29 namespace basegfx 30 { 31 namespace tools 32 { 33 /** Generic linear interpolator 34 35 @tpl ValueType 36 Must have operator+ and operator* defined, and should 37 have value semantics. 38 39 @param t 40 As usual, t must be in the [0,1] range 41 */ lerp(const ValueType & rFrom,const ValueType & rTo,double t)42 template< typename ValueType > ValueType lerp( const ValueType& rFrom, 43 const ValueType& rTo, 44 double t ) 45 { 46 // This is only to suppress a double->int warning. All other 47 // types should be okay here. 48 return static_cast<ValueType>( (1.0-t)*rFrom + t*rTo ); 49 } 50 } 51 } 52 53 #endif /* _BGFX_TOOLS_LERP_HXX */ 54