Persist and show high score. (#42)

Author: karnkaul

.gitignore

@@ -13,3 +13,4 @@ compile_commands.json
 
 imgui.ini
 bave*.log
+/spaced

CMakeLists.txt

@@ -11,7 +11,7 @@ include(FetchContent)
 FetchContent_Declare(
   bave
   GIT_REPOSITORY https://github.com/karnkaul/bave
-  GIT_TAG v0.5.1
+  GIT_TAG v0.5.2
   SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/ext/bave"
 )
 

src/spaced/spaced/game/game_save.cpp

@@ -0,0 +1,33 @@
+#include <bave/persistor.hpp>
+#include <spaced/game/game_save.hpp>
+#include <array>
+#include <cstddef>
+#include <cstring>
+#include <span>
+
+namespace spaced {
+using bave::App;
+using bave::NotNull;
+using bave::Persistor;
+
+namespace {
+constexpr std::string_view uri_v{"spaced/game_save.bin"};
+} // namespace
+
+GameSave::GameSave(NotNull<App const*> app) : m_app(app) {
+	auto const persistor = Persistor{*m_app};
+	if (persistor.exists(uri_v)) {
+		auto const blob_bytes = persistor.read_bytes(uri_v);
+		std::memcpy(&m_blob, blob_bytes.data(), blob_bytes.size());
+	}
+}
+
+GameSave::~GameSave() { save(); }
+
+auto GameSave::save() -> bool {
+	auto const persistor = Persistor{*m_app};
+	auto blob_bytes = std::array<std::byte, sizeof(Blob)>{};
+	std::memcpy(blob_bytes.data(), &m_blob, sizeof(Blob));
+	return persistor.write_bytes(uri_v, blob_bytes);
+}
+} // namespace spaced

src/spaced/spaced/game/game_save.hpp

@@ -0,0 +1,37 @@
+#pragma once
+#include <bave/core/not_null.hpp>
+#include <cstdint>
+
+namespace bave {
+class App;
+}
+
+namespace spaced {
+class GameSave {
+  public:
+	GameSave(GameSave const&) = delete;
+	GameSave(GameSave&&) = delete;
+	auto operator=(GameSave const&) = delete;
+	auto operator=(GameSave&&) = delete;
+
+	explicit GameSave(bave::NotNull<bave::App const*> app);
+	~GameSave();
+
+	[[nodiscard]] auto get_hi_score() const -> std::int64_t { return m_blob.hi_score; }
+	void set_hi_score(std::int64_t const hi_score) { m_blob.hi_score = hi_score; }
+
+	auto save() -> bool;
+
+  private:
+	struct Blob {
+		// struct must remain backwards compatible:
+		// fields must NEVER be removed / reordered!
+		// new fields can be added at the bottom.
+
+		std::int64_t hi_score{};
+	};
+
+	bave::NotNull<bave::App const*> m_app;
+	Blob m_blob{};
+};
+} // namespace spaced

src/spaced/spaced/game/hud.cpp

@@ -14,6 +14,8 @@ Hud::Hud(Services const& services) : ui::View(services), m_styles(&services.get<
 
 void Hud::set_score(std::int64_t const score) { m_score->text.set_string(fmt::format("{}", score)); }
 
+void Hud::set_hi_score(std::int64_t const score) { m_hi_score->text.set_string(fmt::format("HI {}", score)); }
+
 void Hud::create_background() {
 	auto background = std::make_unique<ui::OutlineQuad>();
 	m_background = background.get();
@@ -27,16 +29,29 @@ void Hud::create_background() {
 void Hud::create_score(Services const& services) {
 	auto const& rgbas = m_styles->rgbas;
 
-	auto text = std::make_unique<ui::Text>(services);
+	auto make_text = [&] {
+		auto text = std::make_unique<ui::Text>(services);
+		text->text.set_height(TextHeight{60});
+		text->text.transform.position = m_area.centre();
+		text->text.tint = rgbas["grey"];
+		return text;
+	};
+
+	auto text = make_text();
 	m_score = text.get();
-	text->text.set_height(TextHeight{60});
 	text->text.set_string("9999999999");
-	auto const text_bounds = text->text.get_bounds();
-	auto const text_bounds_size = text_bounds.size();
-	text->text.transform.position = m_area.centre();
+	auto const text_bounds_size = text->text.get_bounds().size();
+	text->text.transform.position.y -= 0.5f * text_bounds_size.y;
+	set_score(0);
+
+	push(std::move(text));
+
+	text = make_text();
+	m_hi_score = text.get();
+	text->text.transform.position.x = m_area.rb.x - 50.0f;
 	text->text.transform.position.y -= 0.5f * text_bounds_size.y;
-	text->text.set_string("0");
-	text->text.tint = rgbas["grey"];
+	text->text.set_align(bave::Text::Align::eLeft);
+	set_hi_score(0);
 
 	push(std::move(text));
 }

src/spaced/spaced/game/hud.hpp

@@ -10,6 +10,7 @@ class Hud : public ui::View {
 	explicit Hud(Services const& services);
 
 	void set_score(std::int64_t score);
+	void set_hi_score(std::int64_t score);
 
   private:
 	void create_background();
@@ -20,5 +21,6 @@ class Hud : public ui::View {
 
 	bave::Ptr<ui::OutlineQuad> m_background{};
 	bave::Ptr<ui::Text> m_score{};
+	bave::Ptr<ui::Text> m_hi_score{};
 };
 } // namespace spaced

src/spaced/spaced/scenes/game.cpp

@@ -37,11 +37,12 @@ auto Game::get_manifest() -> AssetManifest {
 	};
 }
 
-Game::Game(App& app, Services const& services) : Scene(app, services, "Game"), m_world(&services, this) {
+Game::Game(App& app, Services const& services) : Scene(app, services, "Game"), m_save(&app), m_world(&services, this) {
 	clear_colour = services.get<Styles>().rgbas["mocha"];
 
 	auto hud = std::make_unique<Hud>(services);
 	m_hud = hud.get();
+	m_hud->set_hi_score(m_save.get_hi_score());
 	push_view(std::move(hud));
 }
 
@@ -71,6 +72,7 @@ void Game::render(Shader& shader) const { m_world.draw(shader); }
 void Game::add_score(std::int64_t const score) {
 	m_score += score;
 	m_hud->set_score(m_score);
+	update_hi_score();
 }
 
 void Game::on_game_over() {
@@ -86,6 +88,12 @@ void Game::on_game_over() {
 	push_view(std::move(dialog));
 }
 
+void Game::update_hi_score() {
+	if (m_score <= m_save.get_hi_score()) { return; }
+	m_save.set_hi_score(m_score);
+	m_hud->set_hi_score(m_save.get_hi_score());
+}
+
 void Game::inspect(Seconds const dt, Seconds const frame_time) {
 	if constexpr (bave::imgui_v) {
 		m_debug.fps.tick(dt);

src/spaced/spaced/scenes/game.hpp

@@ -1,5 +1,6 @@
 #pragma once
 #include <spaced/assets/asset_manifest.hpp>
+#include <spaced/game/game_save.hpp>
 #include <spaced/game/hud.hpp>
 #include <spaced/game/scorer.hpp>
 #include <spaced/game/target_provider.hpp>
@@ -26,8 +27,11 @@ class Game : public Scene, public IScorer {
 	void add_score(std::int64_t score) final;
 	void on_game_over();
 
+	void update_hi_score();
+
 	void inspect(bave::Seconds dt, bave::Seconds frame_time);
 
+	GameSave m_save;
 	World m_world;
 	std::int64_t m_score{};
 	bave::Ptr<Hud> m_hud{};