OpenShot Audio Library | OpenShotAudio  0.3.2
juce_ProcessorChain.h
1 /*
2  ==============================================================================
3 
4  This file is part of the JUCE library.
5  Copyright (c) 2017 - ROLI Ltd.
6 
7  JUCE is an open source library subject to commercial or open-source
8  licensing.
9 
10  By using JUCE, you agree to the terms of both the JUCE 5 End-User License
11  Agreement and JUCE 5 Privacy Policy (both updated and effective as of the
12  27th April 2017).
13 
14  End User License Agreement: www.juce.com/juce-5-licence
15  Privacy Policy: www.juce.com/juce-5-privacy-policy
16 
17  Or: You may also use this code under the terms of the GPL v3 (see
18  www.gnu.org/licenses).
19 
20  JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
21  EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
22  DISCLAIMED.
23 
24  ==============================================================================
25 */
26 
27 namespace juce
28 {
29 namespace dsp
30 {
31 
32 #ifndef DOXYGEN
33 namespace ProcessorHelpers // Internal helper classes used in building the ProcessorChain
34 {
35  template <int arg>
36  struct AccessHelper
37  {
38  template <typename ProcessorType>
39  static auto& get (ProcessorType& a) noexcept { return AccessHelper<arg - 1>::get (a.processors); }
40 
41  template <typename ProcessorType>
42  static const auto& get (const ProcessorType& a) noexcept { return AccessHelper<arg - 1>::get (a.processors); }
43 
44  template <typename ProcessorType>
45  static void setBypassed (ProcessorType& a, bool bypassed) { AccessHelper<arg - 1>::setBypassed (a.processors, bypassed); }
46  };
47 
48  template <>
49  struct AccessHelper<0>
50  {
51  template <typename ProcessorType>
52  static auto& get (ProcessorType& a) noexcept { return a.getProcessor(); }
53 
54  template <typename ProcessorType>
55  static const auto& get (const ProcessorType& a) noexcept { return a.getProcessor(); }
56 
57  template <typename ProcessorType>
58  static void setBypassed (ProcessorType& a, bool bypassed) { a.isBypassed = bypassed; }
59  };
60 
61  //==============================================================================
62  template <bool isFirst, typename Processor, typename Subclass>
63  struct ChainElement
64  {
65  void prepare (const ProcessSpec& spec)
66  {
67  processor.prepare (spec);
68  }
69 
70  template <typename ProcessContext>
71  void process (const ProcessContext& context) noexcept
72  {
73  if (context.usesSeparateInputAndOutputBlocks() && ! isFirst)
74  {
75  jassert (context.getOutputBlock().getNumChannels() == context.getInputBlock().getNumChannels());
76  ProcessContextReplacing<typename ProcessContext::SampleType> replacingContext (context.getOutputBlock());
77  replacingContext.isBypassed = (isBypassed || context.isBypassed);
78 
79  processor.process (replacingContext);
80  }
81  else
82  {
83  ProcessContext contextCopy (context);
84  contextCopy.isBypassed = (isBypassed || context.isBypassed);
85 
86  processor.process (contextCopy);
87  }
88  }
89 
90  void reset()
91  {
92  processor.reset();
93  }
94 
95  bool isBypassed = false;
96  Processor processor;
97 
98  Processor& getProcessor() noexcept { return processor; }
99  const Processor& getProcessor() const noexcept { return processor; }
100  Subclass& getThis() noexcept { return *static_cast<Subclass*> (this); }
101  const Subclass& getThis() const noexcept { return *static_cast<const Subclass*> (this); }
102 
103  template <int arg> auto& get() noexcept { return AccessHelper<arg>::get (getThis()); }
104  template <int arg> const auto& get() const noexcept { return AccessHelper<arg>::get (getThis()); }
105  template <int arg> void setBypassed (bool bypassed) noexcept { AccessHelper<arg>::setBypassed (getThis(), bypassed); }
106  };
107 
108  //==============================================================================
109  template <bool isFirst, typename FirstProcessor, typename... SubsequentProcessors>
110  struct ChainBase : public ChainElement<isFirst, FirstProcessor, ChainBase<isFirst, FirstProcessor, SubsequentProcessors...>>
111  {
112  using Base = ChainElement<isFirst, FirstProcessor, ChainBase<isFirst, FirstProcessor, SubsequentProcessors...>>;
113 
114  template <typename ProcessContext>
115  void process (const ProcessContext& context) noexcept { Base::process (context); processors.process (context); }
116  void prepare (const ProcessSpec& spec) { Base::prepare (spec); processors.prepare (spec); }
117  void reset() { Base::reset(); processors.reset(); }
118 
119  ChainBase<false, SubsequentProcessors...> processors;
120  };
121 
122  template <bool isFirst, typename ProcessorType>
123  struct ChainBase<isFirst, ProcessorType> : public ChainElement<isFirst, ProcessorType, ChainBase<isFirst, ProcessorType>> {};
124 }
125 #endif
126 
127 
128 //==============================================================================
133 template <typename... Processors>
134 using ProcessorChain = ProcessorHelpers::ChainBase<true, Processors...>;
135 
136 } // namespace dsp
137 } // namespace juce