1*d0626817SAndrew Rist /**************************************************************
2cdf0e10cSrcweir *
3*d0626817SAndrew Rist * Licensed to the Apache Software Foundation (ASF) under one
4*d0626817SAndrew Rist * or more contributor license agreements. See the NOTICE file
5*d0626817SAndrew Rist * distributed with this work for additional information
6*d0626817SAndrew Rist * regarding copyright ownership. The ASF licenses this file
7*d0626817SAndrew Rist * to you under the Apache License, Version 2.0 (the
8*d0626817SAndrew Rist * "License"); you may not use this file except in compliance
9*d0626817SAndrew Rist * with the License. You may obtain a copy of the License at
10*d0626817SAndrew Rist *
11*d0626817SAndrew Rist * http://www.apache.org/licenses/LICENSE-2.0
12*d0626817SAndrew Rist *
13*d0626817SAndrew Rist * Unless required by applicable law or agreed to in writing,
14*d0626817SAndrew Rist * software distributed under the License is distributed on an
15*d0626817SAndrew Rist * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
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20*d0626817SAndrew Rist *************************************************************/
21*d0626817SAndrew Rist
22*d0626817SAndrew Rist
23cdf0e10cSrcweir
24cdf0e10cSrcweir // MARKER(update_precomp.py): autogen include statement, do not remove
25cdf0e10cSrcweir #include "precompiled_basegfx.hxx"
26cdf0e10cSrcweir
27cdf0e10cSrcweir #include "basegfx/tools/keystoplerp.hxx"
28cdf0e10cSrcweir #include <com/sun/star/uno/Sequence.hxx>
29cdf0e10cSrcweir
30cdf0e10cSrcweir #include <algorithm>
31cdf0e10cSrcweir
validateInput(const std::vector<double> & rKeyStops)32cdf0e10cSrcweir static void validateInput(const std::vector<double>& rKeyStops)
33cdf0e10cSrcweir {
34cdf0e10cSrcweir (void)rKeyStops;
35cdf0e10cSrcweir #ifdef DBG_UTIL
36cdf0e10cSrcweir OSL_ENSURE( rKeyStops.size() > 1,
37cdf0e10cSrcweir "KeyStopLerp::KeyStopLerp(): key stop vector must have two entries or more" );
38cdf0e10cSrcweir
39cdf0e10cSrcweir // rKeyStops must be sorted in ascending order
40cdf0e10cSrcweir for( ::std::size_t i=1, len=rKeyStops.size(); i<len; ++i )
41cdf0e10cSrcweir {
42cdf0e10cSrcweir if( rKeyStops[i-1] > rKeyStops[i] )
43cdf0e10cSrcweir OSL_ENSURE( false,
44cdf0e10cSrcweir "KeyStopLerp::KeyStopLerp(): time vector is not sorted in ascending order!" );
45cdf0e10cSrcweir }
46cdf0e10cSrcweir #endif
47cdf0e10cSrcweir }
48cdf0e10cSrcweir
49cdf0e10cSrcweir namespace basegfx
50cdf0e10cSrcweir {
51cdf0e10cSrcweir namespace tools
52cdf0e10cSrcweir {
KeyStopLerp(const std::vector<double> & rKeyStops)53cdf0e10cSrcweir KeyStopLerp::KeyStopLerp( const std::vector<double>& rKeyStops ) :
54cdf0e10cSrcweir maKeyStops(rKeyStops),
55cdf0e10cSrcweir mnLastIndex(0)
56cdf0e10cSrcweir {
57cdf0e10cSrcweir validateInput(maKeyStops);
58cdf0e10cSrcweir }
59cdf0e10cSrcweir
KeyStopLerp(const::com::sun::star::uno::Sequence<double> & rKeyStops)60cdf0e10cSrcweir KeyStopLerp::KeyStopLerp( const ::com::sun::star::uno::Sequence<double>& rKeyStops ) :
61cdf0e10cSrcweir maKeyStops(rKeyStops.getLength()),
62cdf0e10cSrcweir mnLastIndex(0)
63cdf0e10cSrcweir {
64cdf0e10cSrcweir std::copy( rKeyStops.getConstArray(),
65cdf0e10cSrcweir rKeyStops.getConstArray()+rKeyStops.getLength(),
66cdf0e10cSrcweir maKeyStops.begin() );
67cdf0e10cSrcweir validateInput(maKeyStops);
68cdf0e10cSrcweir }
69cdf0e10cSrcweir
lerp(double fAlpha) const70cdf0e10cSrcweir KeyStopLerp::ResultType KeyStopLerp::lerp(double fAlpha) const
71cdf0e10cSrcweir {
72cdf0e10cSrcweir // cached value still okay?
73cdf0e10cSrcweir if( maKeyStops.at(mnLastIndex) < fAlpha ||
74cdf0e10cSrcweir maKeyStops.at(mnLastIndex+1) >= fAlpha )
75cdf0e10cSrcweir {
76cdf0e10cSrcweir // nope, find new index
77cdf0e10cSrcweir mnLastIndex = std::min<std::ptrdiff_t>(
78cdf0e10cSrcweir maKeyStops.size()-2,
79cdf0e10cSrcweir // range is ensured by max below
80cdf0e10cSrcweir std::max<std::ptrdiff_t>(
81cdf0e10cSrcweir 0,
82cdf0e10cSrcweir std::distance( maKeyStops.begin(),
83cdf0e10cSrcweir std::lower_bound( maKeyStops.begin(),
84cdf0e10cSrcweir maKeyStops.end(),
85cdf0e10cSrcweir fAlpha )) - 1 ));
86cdf0e10cSrcweir }
87cdf0e10cSrcweir
88cdf0e10cSrcweir // lerp between stop and stop+1
89cdf0e10cSrcweir const double fRawLerp=
90cdf0e10cSrcweir (fAlpha-maKeyStops.at(mnLastIndex)) /
91cdf0e10cSrcweir (maKeyStops.at(mnLastIndex+1) - maKeyStops.at(mnLastIndex));
92cdf0e10cSrcweir
93cdf0e10cSrcweir // clamp to permissible range (input fAlpha might be
94cdf0e10cSrcweir // everything)
95cdf0e10cSrcweir return ResultType(
96cdf0e10cSrcweir mnLastIndex,
97cdf0e10cSrcweir clamp(fRawLerp,0.0,1.0));
98cdf0e10cSrcweir }
99cdf0e10cSrcweir }
100cdf0e10cSrcweir }
101