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/widget/standardcombos/channellayoutcombobox.h

@@ -19,8 +19,8 @@
 
 ***/
 
-#ifndef CHANNELLAYOUTCOMBOBOX_H
-#define CHANNELLAYOUTCOMBOBOX_H
+#ifndef OAK_CHANNELLAYOUTCOMBOBOX_H
+#define OAK_CHANNELLAYOUTCOMBOBOX_H
 
 #include <olive/core/core.h>
 #include <QComboBox>
@@ -38,16 +38,16 @@ public:
 		: QComboBox(parent)
 	{
 		foreach (const uint64_t &ch_layout,
-				 AudioParams::kSupportedChannelLayouts) {
-			this->addItem(HumanStrings::ChannelLayoutToString(ch_layout),
+				 AudioParams::k_supported_channel_layouts) {
+			this->addItem(HumanStrings::channel_layout_to_string(ch_layout),
 						  QVariant::fromValue(ch_layout));
 		}
 	}
-	[[nodiscard]] uint64_t GetChannelLayout() const
+	[[nodiscard]] uint64_t get_channel_layout() const
 	{
 		return this->currentData().toULongLong();
 	}
-	void SetChannelLayout(uint64_t ch)
+	void set_channel_layout(uint64_t ch)
 	{
 		for (int i = 0; i < this->count(); i++) {
 			if (this->itemData(i).toULongLong() == ch) {
@@ -62,4 +62,4 @@ private:
 
 }
 
-#endif // CHANNELLAYOUTCOMBOBOX_H
+#endif // OAK_CHANNELLAYOUTCOMBOBOX_H

app/widget/standardcombos/frameratecombobox.h

@@ -19,8 +19,8 @@
 
 ***/
 
-#ifndef FRAMERATECOMBOBOX_H
-#define FRAMERATECOMBOBOX_H
+#ifndef OAK_FRAMERATECOMBOBOX_H
+#define OAK_FRAMERATECOMBOBOX_H
 
 #include <QComboBox>
 #include <QEvent>
@@ -46,33 +46,33 @@ public:
 		layout->setContentsMargins(0, 0, 0, 0);
 		layout->addWidget(inner_);
 
-		RepopulateList();
+		repopulate_list();
 
 		old_index_ = 0;
 
 		connect(inner_,
 				static_cast<void (QComboBox::*)(int)>(
 					&QComboBox::currentIndexChanged),
-				this, &FrameRateComboBox::IndexChanged);
+				this, &FrameRateComboBox::index_changed);
 	}
 
-	rational GetFrameRate() const
+	Rational get_frame_rate() const
 	{
 		if (inner_->currentIndex() == inner_->count() - 1) {
 			return custom_rate_;
 		} else {
-			return inner_->currentData().value<rational>();
+			return inner_->currentData().value<Rational>();
 		}
 	}
 
-	void SetFrameRate(const rational &r)
+	void set_frame_rate(const Rational &r)
 	{
 		int standard_rates = inner_->count() - 1;
 		for (int i = 0; i < standard_rates; i++) {
-			if (inner_->itemData(i).value<rational>() == r) {
+			if (inner_->itemData(i).value<Rational>() == r) {
 				// Set standard frame rate
 				old_index_ = i;
-				SetInnerIndexWithoutSignal(i);
+				set_inner_index_without_signal(i);
 				return;
 			}
 		}
@@ -80,12 +80,12 @@ public:
 		// If we're here, set a custom rate
 		custom_rate_ = r;
 		old_index_ = inner_->count() - 1;
-		SetInnerIndexWithoutSignal(old_index_);
-		RepopulateList();
+		set_inner_index_without_signal(old_index_);
+		repopulate_list();
 	}
 
 signals:
-	void FrameRateChanged(const rational &frame_rate);
+	void frame_rate_changed(const Rational &frame_rate);
 
 protected:
 	virtual void changeEvent(QEvent *event) override
@@ -93,12 +93,12 @@ protected:
 		QWidget::changeEvent(event);
 
 		if (event->type() == QEvent::LanguageChange) {
-			RepopulateList();
+			repopulate_list();
 		}
 	}
 
 private slots:
-	void IndexChanged(int index)
+	void index_changed(int index)
 	{
 		if (index == inner_->count() - 1) {
 			// Custom
@@ -106,7 +106,7 @@ private slots:
 			bool ok;
 
 			if (!custom_rate_.isNull()) {
-				s = QString::number(custom_rate_.toDouble());
+				s = QString::number(custom_rate_.to_double());
 			}
 
 			while (true) {
@@ -115,24 +115,24 @@ private slots:
 										  QLineEdit::Normal, s, &ok);
 
 				if (ok) {
-					rational r;
+					Rational r;
 
 					// Try converting to double, assuming most users will input frame rates this way
 					double d = s.toDouble(&ok);
 
 					if (ok) {
 						// Try converting from double
-						r = rational::fromDouble(d, &ok);
+						r = Rational::from_double(d, &ok);
 					} else {
-						// Try converting to rational in case someone formatted that way
-						r = rational::fromString(s.toStdString(), &ok);
+						// Try converting to Rational in case someone formatted that way
+						r = Rational::from_string(s.toStdString(), &ok);
 					}
 
 					if (ok) {
 						custom_rate_ = r;
-						emit FrameRateChanged(r);
+						emit frame_rate_changed(r);
 						old_index_ = index;
-						RepopulateList();
+						repopulate_list();
 						break;
 
 					} else {
@@ -145,18 +145,18 @@ private slots:
 
 				} else {
 					// User cancelled, revert to original value
-					SetInnerIndexWithoutSignal(old_index_);
+					set_inner_index_without_signal(old_index_);
 					break;
 				}
 			}
 		} else {
 			old_index_ = index;
-			emit FrameRateChanged(GetFrameRate());
+			emit frame_rate_changed(get_frame_rate());
 		}
 	}
 
 private:
-	void RepopulateList()
+	void repopulate_list()
 	{
 		int temp_index = inner_->currentIndex();
 
@@ -164,8 +164,8 @@ private:
 
 		inner_->clear();
 
-		foreach (const rational &fr, VideoParams::kSupportedFrameRates) {
-			inner_->addItem(VideoParams::FrameRateToString(fr),
+		foreach (const Rational &fr, VideoParams::k_supported_frame_rates) {
+			inner_->addItem(VideoParams::frame_rate_to_string(fr),
 							QVariant::fromValue(fr));
 		}
 
@@ -174,7 +174,7 @@ private:
 		} else {
 			inner_->addItem(
 				tr("Custom (%1)")
-					.arg(VideoParams::FrameRateToString(custom_rate_)));
+					.arg(VideoParams::frame_rate_to_string(custom_rate_)));
 		}
 
 		// On the first populate there is no current index (-1); select the
@@ -184,7 +184,7 @@ private:
 		inner_->blockSignals(false);
 	}
 
-	void SetInnerIndexWithoutSignal(int index)
+	void set_inner_index_without_signal(int index)
 	{
 		inner_->blockSignals(true);
 		inner_->setCurrentIndex(index);
@@ -193,11 +193,11 @@ private:
 
 	QComboBox *inner_;
 
-	rational custom_rate_;
+	Rational custom_rate_;
 
 	int old_index_;
 };
 
 }
 
-#endif // FRAMERATECOMBOBOX_H
+#endif // OAK_FRAMERATECOMBOBOX_H

app/widget/standardcombos/interlacedcombobox.h

@@ -19,8 +19,8 @@
 
 ***/
 
-#ifndef INTERLACEDCOMBOBOX_H
-#define INTERLACEDCOMBOBOX_H
+#ifndef OAK_INTERLACEDCOMBOBOX_H
+#define OAK_INTERLACEDCOMBOBOX_H
 
 #include <QComboBox>
 
@@ -41,12 +41,12 @@ public:
 		this->addItem(tr("Bottom-Field First"));
 	}
 
-	VideoParams::Interlacing GetInterlaceMode() const
+	VideoParams::Interlacing get_interlace_mode() const
 	{
 		return static_cast<VideoParams::Interlacing>(this->currentIndex());
 	}
 
-	void SetInterlaceMode(VideoParams::Interlacing mode)
+	void set_interlace_mode(VideoParams::Interlacing mode)
 	{
 		this->setCurrentIndex(mode);
 	}
@@ -54,4 +54,4 @@ public:
 
 }
 
-#endif // INTERLACEDCOMBOBOX_H
+#endif // OAK_INTERLACEDCOMBOBOX_H

app/widget/standardcombos/pixelaspectratiocombobox.h

@@ -19,8 +19,8 @@
 
 ***/
 
-#ifndef PIXELASPECTRATIOCOMBOBOX_H
-#define PIXELASPECTRATIOCOMBOBOX_H
+#ifndef OAK_PIXELASPECTRATIOCOMBOBOX_H
+#define OAK_PIXELASPECTRATIOCOMBOBOX_H
 
 #include <QComboBox>
 
@@ -37,9 +37,9 @@ public:
 		: QComboBox(parent)
 		, dont_prompt_custom_par_(false)
 	{
-		QStringList par_names = VideoParams::GetStandardPixelAspectRatioNames();
-		for (int i = 0; i < VideoParams::kStandardPixelAspects.size(); i++) {
-			const rational &ratio = VideoParams::kStandardPixelAspects.at(i);
+		QStringList par_names = VideoParams::get_standard_pixel_aspect_ratio_names();
+		for (int i = 0; i < VideoParams::k_standard_pixel_aspects.size(); i++) {
+			const Rational &ratio = VideoParams::k_standard_pixel_aspects.at(i);
 
 			this->addItem(par_names.at(i), QVariant::fromValue(ratio));
 		}
@@ -47,39 +47,39 @@ public:
 		// Always add custom item last, much of the logic relies on this. Set this to the current AR so
 		// that if none of the above are ==, it will eventually select this item
 		this->addItem(QString());
-		UpdateCustomItem(rational());
+		update_custom_item(Rational());
 
 		// Pick up index signal to query for custom aspect ratio if requested
 		connect(this,
 				static_cast<void (QComboBox::*)(int)>(
 					&QComboBox::currentIndexChanged),
-				this, &PixelAspectRatioComboBox::IndexChanged);
+				this, &PixelAspectRatioComboBox::index_changed);
 	}
 
-	rational GetPixelAspectRatio() const
+	Rational get_pixel_aspect_ratio() const
 	{
-		return this->currentData().value<rational>();
+		return this->currentData().value<Rational>();
 	}
 
-	void SetPixelAspectRatio(const rational &r)
+	void set_pixel_aspect_ratio(const Rational &r)
 	{
 		// Determine which index to select on startup
 		for (int i = 0; i < this->count(); i++) {
-			if (this->itemData(i).value<rational>() == r) {
+			if (this->itemData(i).value<Rational>() == r) {
 				this->setCurrentIndex(i);
 				return;
 			}
 		}
 
 		// Must not have found the ratio, so it must be custom
-		UpdateCustomItem(r);
+		update_custom_item(r);
 		dont_prompt_custom_par_ = true;
 		this->setCurrentIndex(this->count() - 1);
 		dont_prompt_custom_par_ = false;
 	}
 
 private slots:
-	void IndexChanged(int index)
+	void index_changed(int index)
 	{
 		if (dont_prompt_custom_par_) {
 			return;
@@ -90,17 +90,17 @@ private slots:
 			// Query for custom pixel aspect ratio
 			bool ok;
 
-			double custom_ratio = GetFloatRatioFromUser(
+			double custom_ratio = get_float_ratio_from_user(
 				this, tr("Set Custom Pixel Aspect Ratio"), &ok);
 
 			if (ok) {
-				UpdateCustomItem(rational::fromDouble(custom_ratio));
+				update_custom_item(Rational::from_double(custom_ratio));
 			}
 		}
 	}
 
 private:
-	void UpdateCustomItem(const rational &ratio)
+	void update_custom_item(const Rational &ratio)
 	{
 		const int custom_index = this->count() - 1;
 
@@ -108,10 +108,10 @@ private:
 			this->setItemText(custom_index, tr("Custom..."));
 
 			// Use 1:1 to prevent any real chance of the PAR being set to 0
-			this->setItemData(custom_index, QVariant::fromValue(rational(1)));
+			this->setItemData(custom_index, QVariant::fromValue(Rational(1)));
 		} else {
 			this->setItemText(custom_index,
-							  VideoParams::FormatPixelAspectRatioString(
+							  VideoParams::format_pixel_aspect_ratio_string(
 								  tr("Custom (%1)"), ratio));
 			this->setItemData(custom_index, QVariant::fromValue(ratio));
 		}
@@ -122,4 +122,4 @@ private:
 
 }
 
-#endif // PIXELASPECTRATIOCOMBOBOX_H
+#endif // OAK_PIXELASPECTRATIOCOMBOBOX_H

app/widget/standardcombos/pixelformatcombobox.h

@@ -19,8 +19,8 @@
 
 ***/
 
-#ifndef PIXELFORMATCOMBOBOX_H
-#define PIXELFORMATCOMBOBOX_H
+#ifndef OAK_PIXELFORMATCOMBOBOX_H
+#define OAK_PIXELFORMATCOMBOBOX_H
 
 #include <QComboBox>
 
@@ -36,22 +36,22 @@ public:
 		: QComboBox(parent)
 	{
 		// Set up preview formats
-		for (int i = 0; i < PixelFormat::COUNT; i++) {
+		for (int i = 0; i < PixelFormat::count; i++) {
 			PixelFormat pix_fmt = static_cast<PixelFormat::Format>(i);
 
 			if (!float_only || pix_fmt.is_float()) {
-				this->addItem(VideoParams::GetFormatName(pix_fmt),
+				this->addItem(VideoParams::get_format_name(pix_fmt),
 							  static_cast<PixelFormat::Format>(pix_fmt));
 			}
 		}
 	}
 
-	PixelFormat GetPixelFormat() const
+	PixelFormat get_pixel_format() const
 	{
 		return static_cast<PixelFormat::Format>(this->currentData().toInt());
 	}
 
-	void SetPixelFormat(PixelFormat fmt)
+	void set_pixel_format(PixelFormat fmt)
 	{
 		for (int i = 0; i < this->count(); i++) {
 			if (this->itemData(i).toInt() == fmt) {
@@ -64,4 +64,4 @@ public:
 
 }
 
-#endif // PIXELFORMATCOMBOBOX_H
+#endif // OAK_PIXELFORMATCOMBOBOX_H

app/widget/standardcombos/sampleformatcombobox.h

@@ -19,8 +19,8 @@
 
 ***/
 
-#ifndef SAMPLEFORMATCOMBOBOX_H
-#define SAMPLEFORMATCOMBOBOX_H
+#ifndef OAK_SAMPLEFORMATCOMBOBOX_H
+#define OAK_SAMPLEFORMATCOMBOBOX_H
 
 #include <olive/core/core.h>
 #include <QComboBox>
@@ -41,54 +41,54 @@ public:
 	{
 	}
 
-	void SetAttemptToRestoreFormat(bool e)
+	void set_attempt_to_restore_format(bool e)
 	{
 		attempt_to_restore_format_ = e;
 	}
 
-	void SetAvailableFormats(const std::vector<SampleFormat> &formats)
+	void set_available_formats(const std::vector<SampleFormat> &formats)
 	{
-		SampleFormat tmp = SampleFormat::INVALID;
+		SampleFormat tmp = SampleFormat::invalid;
 
 		if (attempt_to_restore_format_) {
-			tmp = GetSampleFormat();
+			tmp = get_sample_format();
 		}
 
 		clear();
 		foreach (const SampleFormat &of, formats) {
-			AddFormatItem(of);
+			add_format_item(of);
 		}
 
 		if (attempt_to_restore_format_) {
-			SetSampleFormat(tmp);
+			set_sample_format(tmp);
 		}
 	}
 
-	void SetPackedFormats()
+	void set_packed_formats()
 	{
-		SampleFormat tmp = SampleFormat::INVALID;
+		SampleFormat tmp = SampleFormat::invalid;
 
 		if (attempt_to_restore_format_) {
-			tmp = GetSampleFormat();
+			tmp = get_sample_format();
 		}
 
 		clear();
-		for (int i = SampleFormat::PACKED_START; i < SampleFormat::PACKED_END;
+		for (int i = SampleFormat::packed_start; i < SampleFormat::packed_end;
 			 i++) {
-			AddFormatItem(static_cast<SampleFormat::Format>(i));
+			add_format_item(static_cast<SampleFormat::Format>(i));
 		}
 
 		if (attempt_to_restore_format_) {
-			SetSampleFormat(tmp);
+			set_sample_format(tmp);
 		}
 	}
 
-	SampleFormat GetSampleFormat() const
+	SampleFormat get_sample_format() const
 	{
 		return static_cast<SampleFormat::Format>(this->currentData().toInt());
 	}
 
-	void SetSampleFormat(SampleFormat fmt)
+	void set_sample_format(SampleFormat fmt)
 	{
 		for (int i = 0; i < this->count(); i++) {
 			if (this->itemData(i).toInt() == fmt) {
@@ -99,9 +99,9 @@ public:
 	}
 
 private:
-	void AddFormatItem(SampleFormat f)
+	void add_format_item(SampleFormat f)
 	{
-		this->addItem(HumanStrings::FormatToString(f),
+		this->addItem(HumanStrings::format_to_string(f),
 					  static_cast<SampleFormat::Format>(f));
 	}
 
@@ -110,4 +110,4 @@ private:
 
 }
 
-#endif // SAMPLEFORMATCOMBOBOX_H
+#endif // OAK_SAMPLEFORMATCOMBOBOX_H

app/widget/standardcombos/sampleratecombobox.h

@@ -19,8 +19,8 @@
 
 ***/
 
-#ifndef SAMPLERATECOMBOBOX_H
-#define SAMPLERATECOMBOBOX_H
+#ifndef OAK_SAMPLERATECOMBOBOX_H
+#define OAK_SAMPLERATECOMBOBOX_H
 
 #include <olive/core/core.h>
 #include <QComboBox>
@@ -38,17 +38,17 @@ public:
 	SampleRateComboBox(QWidget *parent = nullptr)
 		: QComboBox(parent)
 	{
-		foreach (int sr, AudioParams::kSupportedSampleRates) {
-			this->addItem(HumanStrings::SampleRateToString(sr), sr);
+		foreach (int sr, AudioParams::k_supported_sample_rates) {
+			this->addItem(HumanStrings::sample_rate_to_string(sr), sr);
 		}
 	}
 
-	int GetSampleRate() const
+	int get_sample_rate() const
 	{
 		return this->currentData().toInt();
 	}
 
-	void SetSampleRate(int rate)
+	void set_sample_rate(int rate)
 	{
 		for (int i = 0; i < this->count(); i++) {
 			if (this->itemData(i).toInt() == rate) {
@@ -61,4 +61,4 @@ public:
 
 }
 
-#endif // SAMPLERATECOMBOBOX_H
+#endif // OAK_SAMPLERATECOMBOBOX_H

app/widget/standardcombos/standardcombos.h

@@ -18,8 +18,8 @@
 
 ***/
 
-#ifndef STANDARDCOMBOS_H
-#define STANDARDCOMBOS_H
+#ifndef OAK_STANDARDCOMBOS_H
+#define OAK_STANDARDCOMBOS_H
 
 #include "channellayoutcombobox.h"
 #include "frameratecombobox.h"
@@ -30,4 +30,4 @@
 #include "sampleratecombobox.h"
 #include "videodividercombobox.h"
 
-#endif // STANDARDCOMBOS_H
+#endif // OAK_STANDARDCOMBOS_H

app/widget/standardcombos/videodividercombobox.h

@@ -19,8 +19,8 @@
 
 ***/
 
-#ifndef VIDEODIVIDERCOMBOBOX_H
-#define VIDEODIVIDERCOMBOBOX_H
+#ifndef OAK_VIDEODIVIDERCOMBOBOX_H
+#define OAK_VIDEODIVIDERCOMBOBOX_H
 
 #include <QComboBox>
 
@@ -35,17 +35,17 @@ public:
 	VideoDividerComboBox(QWidget *parent = nullptr)
 		: QComboBox(parent)
 	{
-		foreach (int d, VideoParams::kSupportedDividers) {
-			this->addItem(VideoParams::GetNameForDivider(d), d);
+		foreach (int d, VideoParams::k_supported_dividers) {
+			this->addItem(VideoParams::get_name_for_divider(d), d);
 		}
 	}
 
-	int GetDivider() const
+	int get_divider() const
 	{
 		return this->currentData().toInt();
 	}
 
-	void SetDivider(int d)
+	void set_divider(int d)
 	{
 		for (int i = 0; i < this->count(); i++) {
 			if (this->itemData(i).toInt() == d) {
@@ -58,4 +58,4 @@ public:
 
 }
 
-#endif // VIDEODIVIDERCOMBOBOX_H
+#endif // OAK_VIDEODIVIDERCOMBOBOX_H