style: unify identifier naming per updated conventions

Automated with clang-tidy readability-identifier-naming (config added to
.clang-tidy) plus scripted passes, per the updated rules now documented
in CONTRIBUTING.md:

- types (class/struct/enum/alias/template params): PascalCase
- functions, variables, members: snake_case (incl. rational -> Rational)
- private/protected members: trailing underscore; static member
  variables likewise (instance_, available_themes_)
- constants and enum values: snake_case (kLinear -> k_linear,
  F32P -> f32p); ALL_CAPS reserved for macros
- macros: OAK_ prefix (OLIVE_ADD_TEST/OLIVE_ASSERT/OLIVE_CONFIG ->
  OAK_ADD_TEST/OAK_ASSERT/OAK_CONFIG, GL_PREAMBLE -> OAK_GL_PREAMBLE,
  include guards -> OAK_*)
- file names: all lowercase (Current/Plugin/OliveHost/OliveClip/
  OlivePluginInstance -> current/plugin/olivehost/oliveclip/
  oliveplugininstance)
- getters share the member name sans underscore, setters set_foo()
- Qt and third-party (OpenFX) virtual overrides and framework callbacks
  keep their original names (exempt in .clang-tidy)

Manual follow-ups required where automation could not reach:
- string-based QMetaObject/SIGNAL/SLOT references updated to renamed
  methods (AddTask, CreatedFile, DeleteSpecificFile, moveSelectionUp, ...)
- macro bodies referencing renamed methods (OLIVE_CONFIG,
  NODE_DEFAULT_DESTRUCTOR, MANAGEDDISPLAYWIDGET_*)
- self-shadowing locals renamed where signals/methods became same-named
  (size_changed, worker_count, selected_items, import param, filters)
- third_party OFX member/namespace usages restored (OFX::Host::*,
  _created, _clipPrefsDirty, createInstance, clearPersistentMessage)
- STL protocol aliases restored (const_iterator) with .clang-tidy
  ignore rules; qHash overloads restored

Full build and test suite pass: ctest 4/4, ~1960 gtest cases green.

app/render/audiowaveformcache.cpp

@@ -32,51 +32,51 @@ AudioWaveformCache::AudioWaveformCache(QObject *parent)
 	waveforms_ = std::make_shared<AudioVisualWaveform>();
 }
 
-void AudioWaveformCache::WriteWaveform(const TimeRange &range,
+void AudioWaveformCache::write_waveform(const TimeRange &range,
 									   const TimeRangeList &valid_ranges,
 									   const AudioVisualWaveform *waveform)
 {
 	// Write each valid range to the segments
 	foreach (const TimeRange &r, valid_ranges) {
 		if (waveform) {
-			waveforms_->OverwriteSums(*waveform, r.in(), r.in() - range.in(),
+			waveforms_->overwrite_sums(*waveform, r.in(), r.in() - range.in(),
 									  r.length());
 		}
 
-		Validate(r);
+		validate(r);
 	}
 }
 
-void DrawSubRect(QPainter *painter, const QRect &rect, const double &scale,
+void draw_sub_rect(QPainter *painter, const QRect &rect, const double &scale,
 				 const TimeRange &wave_range,
 				 const AudioVisualWaveform &waveform, const TimeRange &subrange)
 {
 	// Find start time of passthrough
-	TimeRange intersect = wave_range.Intersected(subrange);
+	TimeRange intersect = wave_range.intersected(subrange);
 
 	// Create new rect that starts at the offset of pass_start from start_time
 	// Set rect width to either length of passthrough or until the end
 	QRect pass_rect(
-		rect.x() + (intersect.in() - wave_range.in()).toDouble() * scale,
-		rect.y(), intersect.length().toDouble() * scale, rect.height());
+		rect.x() + (intersect.in() - wave_range.in()).to_double() * scale,
+		rect.y(), intersect.length().to_double() * scale, rect.height());
 
 	// Draw waveform with this info
-	AudioVisualWaveform::DrawWaveform(painter, pass_rect, scale, waveform,
+	AudioVisualWaveform::draw_waveform(painter, pass_rect, scale, waveform,
 									  intersect.in());
 }
 
 void AudioWaveformCache::Draw(QPainter *painter, const QRect &rect,
 							  const double &scale,
-							  const rational &start_time) const
+							  const Rational &start_time) const
 {
 	if (!passthroughs_.empty()) {
 		TimeRange wave_range(start_time,
 							 start_time +
-								 rational::fromDouble(rect.width() / scale));
+								 Rational::from_double(rect.width() / scale));
 		TimeRangeList draw_range = { wave_range };
 		for (const WaveformPassthrough &p : passthroughs_) {
-			if (draw_range.OverlapsWith(p, true, false)) {
-				DrawSubRect(painter, rect, scale, wave_range, *p.waveform, p);
+			if (draw_range.overlaps_with(p, true, false)) {
+				draw_sub_rect(painter, rect, scale, wave_range, *p.waveform, p);
 
 				// Remove this range
 				draw_range.remove(p);
@@ -84,31 +84,31 @@ void AudioWaveformCache::Draw(QPainter *painter, const QRect &rect,
 		}
 
 		for (const TimeRange &r : draw_range) {
-			DrawSubRect(painter, rect, scale, wave_range, *waveforms_, r);
+			draw_sub_rect(painter, rect, scale, wave_range, *waveforms_, r);
 		}
 	} else {
-		AudioVisualWaveform::DrawWaveform(painter, rect, scale, *waveforms_,
+		AudioVisualWaveform::draw_waveform(painter, rect, scale, *waveforms_,
 										  start_time);
 	}
 }
 
 AudioVisualWaveform::Sample
-AudioWaveformCache::GetSummaryFromTime(const rational &start,
-									   const rational &length) const
+AudioWaveformCache::get_summary_from_time(const Rational &start,
+									   const Rational &length) const
 {
-	return waveforms_->GetSummaryFromTime(start, length);
+	return waveforms_->get_summary_from_time(start, length);
 }
 
-rational AudioWaveformCache::length() const
+Rational AudioWaveformCache::length() const
 {
 	return waveforms_->length();
 }
 
-void AudioWaveformCache::SetPassthrough(PlaybackCache *cache)
+void AudioWaveformCache::set_passthrough(PlaybackCache *cache)
 {
 	AudioWaveformCache *c = static_cast<AudioWaveformCache *>(cache);
 
-	for (const TimeRange &r : c->GetValidatedRanges()) {
+	for (const TimeRange &r : c->get_validated_ranges()) {
 		WaveformPassthrough t = r;
 		t.waveform = c->waveforms_;
 		passthroughs_.push_back(t);
@@ -116,8 +116,8 @@ void AudioWaveformCache::SetPassthrough(PlaybackCache *cache)
 	passthroughs_.insert(passthroughs_.end(), c->passthroughs_.begin(),
 						 c->passthroughs_.end());
 
-	SetParameters(c->GetParameters());
-	SetSavingEnabled(c->IsSavingEnabled());
+	set_parameters(c->get_parameters());
+	set_saving_enabled(c->is_saving_enabled());
 }
 
 void AudioWaveformCache::InvalidateEvent(const TimeRange &range)