media: add "options" cvar abstraction

src/media/CMakeLists.txt

@@ -2,6 +2,8 @@ target_sources(SRB2SDL2 PRIVATE
 	audio_encoder.hpp
 	container.hpp
 	encoder.hpp
+	options.cpp
+	options.hpp
 	video_encoder.hpp
 	video_frame.hpp
 )

src/media/options.cpp

@@ -0,0 +1,118 @@
+// RING RACERS
+//-----------------------------------------------------------------------------
+// Copyright (C) 2023 by James Robert Roman
+//
+// This program is free software distributed under the
+// terms of the GNU General Public License, version 2.
+// See the 'LICENSE' file for more details.
+//-----------------------------------------------------------------------------
+
+#include <cstddef>
+#include <cstdint>
+#include <vector>
+
+#include <fmt/format.h>
+
+#include "../cxxutil.hpp"
+#include "../m_fixed.h"
+#include "options.hpp"
+
+using namespace srb2::media;
+
+static std::vector<consvar_t*> g_cvars;
+
+Options::Options(const char* prefix, map_t map) : prefix_(prefix), map_(map)
+{
+	for (auto& [suffix, cvar] : map_)
+	{
+		cvar.name = strdup(fmt::format("{}_{}", prefix_, suffix).c_str());
+		g_cvars.emplace_back(&cvar);
+	}
+}
+
+const consvar_t& Options::cvar(const char* option) const
+{
+	const consvar_t& cvar = map_.at(option);
+
+	SRB2_ASSERT(cvar.string != nullptr);
+
+	return cvar;
+}
+
+template <>
+int Options::get<int>(const char* option) const
+{
+	return cvar(option).value;
+}
+
+template <>
+float Options::get<float>(const char* option) const
+{
+	return FixedToFloat(cvar(option).value);
+}
+
+static consvar_t range_cvar(const char* default_value, int32_t min, int32_t max, int32_t flags = 0)
+{
+	return CVAR_INIT(
+		nullptr,
+		default_value,
+		CV_SAVE | flags,
+		new CV_PossibleValue_t[] {{min, "MIN"}, {max, "MAX"}, {}},
+		nullptr
+	);
+}
+
+template <>
+consvar_t Options::range<float>(const char* default_value, float min, float max)
+{
+	return range_cvar(default_value, FloatToFixed(min), FloatToFixed(max), CV_FLOAT);
+}
+
+template <>
+consvar_t Options::range_min<float>(const char* default_value, float min)
+{
+	return range_cvar(default_value, FloatToFixed(min), INT32_MAX);
+}
+
+template <>
+consvar_t Options::range<int>(const char* default_value, int min, int max)
+{
+	return range_cvar(default_value, min, max);
+}
+
+template <>
+consvar_t Options::range_min<int>(const char* default_value, int min)
+{
+	return range_cvar(default_value, min, INT32_MAX);
+}
+
+template <>
+consvar_t Options::value_map<int>(const char* default_value, std::map<const char*, int> values)
+{
+	auto* arr = new CV_PossibleValue_t[values.size() + 1];
+
+	std::size_t i = 0;
+
+	for (const auto& [k, v] : values)
+	{
+		arr[i].value = v;
+		arr[i].strvalue = k;
+
+		i++;
+	}
+
+	arr[i].value = 0;
+	arr[i].strvalue = nullptr;
+
+	return CVAR_INIT(nullptr, default_value, CV_SAVE, arr, nullptr);
+}
+
+void srb2::media::register_options()
+{
+	for (auto cvar : g_cvars)
+	{
+		CV_RegisterVar(cvar);
+	}
+
+	g_cvars = {};
+}

src/media/options.hpp

@@ -0,0 +1,51 @@
+// RING RACERS
+//-----------------------------------------------------------------------------
+// Copyright (C) 2023 by James Robert Roman
+//
+// This program is free software distributed under the
+// terms of the GNU General Public License, version 2.
+// See the 'LICENSE' file for more details.
+//-----------------------------------------------------------------------------
+
+#ifndef __SRB2_MEDIA_OPTIONS_HPP__
+#define __SRB2_MEDIA_OPTIONS_HPP__
+
+#include <map>
+#include <unordered_map>
+
+#include "../command.h"
+
+namespace srb2::media
+{
+
+class Options
+{
+public:
+	using map_t = std::unordered_map<const char*, consvar_t>;
+
+	Options(const char* prefix, map_t map);
+
+	template <typename T>
+	T get(const char* option) const;
+
+	template <typename T>
+	static consvar_t range(const char* default_value, T min, T max);
+
+	template <typename T>
+	static consvar_t range_min(const char* default_value, T min);
+
+	template <typename T>
+	static consvar_t value_map(const char* default_value, std::map<const char*, T> values);
+
+private:
+	const char* prefix_;
+	map_t map_;
+
+	const consvar_t& cvar(const char* option) const;
+};
+
+void register_options();
+
+}; // namespace srb2::media
+
+#endif // __SRB2_MEDIA_OPTIONS_HPP__