Add World and related tech. (#25)

* bave update (unstable).

* Load emitters from data files.

* Support multi-stage async loads.

* Add and use `AssetList` for staged loading.

* Add and use `EnemyFactory`.

* Add and use `World`.

Refactor enemy spawner factory to be an `IEnemyFactory`, able to customize multiple virtual functions.

* Use a vector of enemy spawners in `Game`.

Delegate inspection and auto-spawn to spawner / factory.

* Rename `World` to `WorldSpec`.

* Add and use `World`.

* CI build fixes.

* Load player tint from world spec.

* Update bave to stable 0.4.8.

* Use `type_name` instead of `type`.

Author: karnkaul

CMakeLists.txt

@@ -11,7 +11,7 @@ include(FetchContent)
 FetchContent_Declare(
   bave
   GIT_REPOSITORY https://github.com/karnkaul/bave
-  GIT_TAG 13ef94fe81e8914335b903c37c58bb2207fd786d # v0.4.7
+  GIT_TAG 8717d1eafd2ac581c7b90fa3af384eb66cd7896a # v0.4.8
   SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/ext/bave"
 )
 

assets/particles/exhaust.json

@@ -0,0 +1,61 @@
+{
+  "asset_type": "ParticleEmitter",
+  "texture": "images/foam_bubble.png",
+  "config": {
+    "initial": {
+      "position": {
+        "lo": [
+          0.000000,
+          0.000000
+        ],
+        "hi": [
+          0.000000,
+          0.000000
+        ]
+      },
+      "rotation": 0.000000
+    },
+    "velocity": {
+      "linear": {
+        "angle": {
+          "lo": 80.000000,
+          "hi": 100.000000
+        },
+        "speed": {
+          "lo": -360.000000,
+          "hi": -270.000000
+        }
+      },
+      "angular": {
+        "lo": -90.000000,
+        "hi": 90.000000
+      }
+    },
+    "lerp": {
+      "tint": {
+        "lo": "#231d2aff",
+        "hi": "#231d2aff"
+      },
+      "scale": {
+        "lo": [
+          1.000000,
+          1.000000
+        ],
+        "hi": [
+          0.500000,
+          0.500000
+        ]
+      }
+    },
+    "ttl": {
+      "lo": 2.000000,
+      "hi": 3.000000
+    },
+    "quad_size": [
+      80.000000,
+      80.000000
+    ],
+    "count": 80,
+    "respawn": true
+  }
+}

assets/particles/explode.json

@@ -0,0 +1,61 @@
+{
+  "asset_type": "ParticleEmitter",
+  "texture": "images/foam_bubble.png",
+  "config": {
+    "initial": {
+      "position": {
+        "lo": [
+          0.000000,
+          0.000000
+        ],
+        "hi": [
+          0.000000,
+          0.000000
+        ]
+      },
+      "rotation": 0.000000
+    },
+    "velocity": {
+      "linear": {
+        "angle": {
+          "lo": -180.000000,
+          "hi": 180.000000
+        },
+        "speed": {
+          "lo": -360.000000,
+          "hi": -80.000000
+        }
+      },
+      "angular": {
+        "lo": -90.000000,
+        "hi": 90.000000
+      }
+    },
+    "lerp": {
+      "tint": {
+        "lo": "#f75c03ff",
+        "hi": "#e5cdaeff"
+      },
+      "scale": {
+        "lo": [
+          1.000000,
+          1.000000
+        ],
+        "hi": [
+          0.700000,
+          0.700000
+        ]
+      }
+    },
+    "ttl": {
+      "lo": 0.500000,
+      "hi": 3.000000
+    },
+    "quad_size": [
+      50.000000,
+      50.000000
+    ],
+    "count": 40,
+    "respawn": true
+  }
+}

assets/worlds/playground.json

@@ -0,0 +1,19 @@
+{
+  "name": "Playground",
+  "background_tint": "mocha",
+  "player": {
+    "tint": "black",
+    "exhaust_emitter": "particles/exhaust.json"
+  },
+  "enemy_factories": [
+    {
+      "type_name": "BasicCreepFactory",
+      "tints": [
+        "orange",
+        "milk"
+      ],
+      "spawn_rate": 2,
+      "death_emitter": "particles/explode.json"
+    }
+  ]
+}

src/spaced/spaced/async_exec.cpp

@@ -1,26 +1,60 @@
 #include <spaced/async_exec.hpp>
+#include <cassert>
+#include <iterator>
+#include <numeric>
 
 namespace spaced {
 using namespace std::chrono_literals;
 
-AsyncExec::AsyncExec(std::span<std::function<void()>> tasks) {
+AsyncExec::AsyncExec(std::span<Task const> tasks) {
+	if (tasks.empty()) { return; }
+
+	m_total = static_cast<int>(tasks.size());
+	enqueue(tasks);
+}
+
+AsyncExec::AsyncExec(std::span<Stage> stages) {
+	if (stages.empty()) { return; }
+	std::move(stages.begin(), stages.end(), std::back_inserter(m_stages));
+	m_total = std::accumulate(m_stages.begin(), m_stages.end(), 0, [](int count, auto const& tasks) { return static_cast<int>(tasks.size()) + count; });
+	start_next_stage();
+}
+
+auto AsyncExec::update() -> Status {
+	if (m_remain.empty()) {
+		if (m_stages.empty()) { return Status{.remain = 0, .total = m_total}; }
+		start_next_stage();
+	}
+	std::erase_if(m_remain, [](std::future<void> const& future) { return !future.valid() || future.wait_for(0s) == std::future_status::ready; });
+	return Status{.remain = m_total - m_completed, .total = m_total};
+}
+
+void AsyncExec::start_next_stage() {
+	if (m_stages.empty()) { return; }
+
+	auto get_next_stage = [&] {
+		auto ret = std::move(m_stages.front());
+		m_stages.pop_front();
+		return ret;
+	};
+
+	auto stage = get_next_stage();
+	while (stage.empty() && !m_stages.empty()) { stage = get_next_stage(); }
+
+	enqueue(stage);
+}
+
+void AsyncExec::enqueue(std::span<Task const> tasks) {
+	assert(m_remain.empty());
 	if (tasks.empty()) { return; }
 
 	m_remain.reserve(tasks.size());
-	for (auto& task : tasks) {
-		auto func = [task = std::move(task), this] {
+	for (auto const& task : tasks) {
+		auto func = [task = task, this] {
 			task();
 			++m_completed;
 		};
 		m_remain.push_back(std::async(std::move(func)));
 	}
-
-	m_total = static_cast<int>(m_remain.size());
-}
-
-auto AsyncExec::update() -> Status {
-	if (m_remain.empty()) { return Status{.remain = 0, .total = m_total}; }
-	std::erase_if(m_remain, [](std::future<void> const& future) { return !future.valid() || future.wait_for(0s) == std::future_status::ready; });
-	return Status{.remain = static_cast<int>(m_remain.size()), .total = m_total};
 }
 } // namespace spaced

src/spaced/spaced/async_exec.hpp

@@ -1,5 +1,6 @@
 #pragma once
 #include <atomic>
+#include <deque>
 #include <functional>
 #include <future>
 #include <span>
@@ -8,14 +9,22 @@
 namespace spaced {
 class AsyncExec {
   public:
+	using Task = std::function<void()>;
+	using Stage = std::vector<Task>;
+
 	struct Status;
 
-	explicit AsyncExec(std::span<std::function<void()>> tasks);
+	explicit AsyncExec(std::span<Task const> tasks);
+	explicit AsyncExec(std::span<Stage> stages);
 
 	auto update() -> Status;
 
   private:
+	void start_next_stage();
+	void enqueue(std::span<Task const> tasks);
+
 	std::vector<std::future<void>> m_remain{};
+	std::deque<Stage> m_stages{};
 	std::atomic<int> m_completed{};
 	int m_total{};
 };

src/spaced/spaced/game/asset_list.cpp

@@ -0,0 +1,79 @@
+#include <spaced/game/asset_list.hpp>
+#include <spaced/game/asset_loader.hpp>
+#include <spaced/services/resources.hpp>
+
+namespace spaced {
+using bave::Loader;
+
+AssetList::AssetList(Loader loader, Services const& services) : m_loader(std::move(loader)), m_resources(&services.get<Resources>()) {}
+
+auto AssetList::add_texture(std::string uri, bool const mip_map) -> AssetList& {
+	if (uri.empty()) { return *this; }
+	m_textures.insert(Tex{.uri = std::move(uri), .mip_map = mip_map});
+	return *this;
+}
+
+auto AssetList::add_font(std::string uri) -> AssetList& {
+	if (uri.empty()) { return *this; }
+	m_fonts.insert(std::move(uri));
+	return *this;
+}
+
+auto AssetList::add_particle_emitter(std::string uri) -> AssetList& {
+	if (uri.empty()) { return *this; }
+
+	auto const json = m_loader.load_json(uri);
+	if (!json) { return *this; }
+
+	// emitters require textures (stage 0) to be loaded, and must be loaded in stage 1
+	if (auto const& texture = json["texture"]) { add_texture(texture.as<std::string>()); }
+	m_emitters.insert(std::move(uri));
+	return *this;
+}
+
+auto AssetList::read_world_spec(std::string_view const uri) -> WorldSpec {
+	if (uri.empty()) { return {}; }
+
+	auto const json = m_loader.load_json(uri);
+	if (!json) { return {}; }
+
+	auto ret = WorldSpec{};
+	ret.name = json["name"].as_string();
+	ret.background_tint = json["background_tint"].as_string();
+
+	if (auto const& player = json["player"]) {
+		ret.player.tint = player["tint"].as_string();
+		ret.player.exhaust_emitter = player["exhaust_emitter"].as_string();
+		add_particle_emitter(ret.player.exhaust_emitter);
+	}
+
+	for (auto const& enemy_factory : json["enemy_factories"].array_view()) {
+		add_particle_emitter(enemy_factory["death_emitter"].as<std::string>());
+		ret.enemy_factories.push_back(enemy_factory);
+	}
+
+	return ret;
+}
+
+auto AssetList::build_task_stages() const -> std::vector<AsyncExec::Stage> {
+	auto ret = std::vector<AsyncExec::Stage>{};
+	ret.reserve(2);
+	auto asset_loader = AssetLoader{m_loader, m_resources};
+	ret.push_back(build_stage_0(asset_loader));
+	ret.push_back(build_stage_1(asset_loader));
+	return ret;
+}
+
+auto AssetList::build_stage_0(AssetLoader& asset_loader) const -> AsyncExec::Stage {
+	auto ret = AsyncExec::Stage{};
+	for (auto const& texture : m_textures) { ret.push_back(asset_loader.make_load_texture(texture.uri, texture.mip_map)); }
+	for (auto const& font : m_fonts) { ret.push_back(asset_loader.make_load_font(font)); }
+	return ret;
+}
+
+auto AssetList::build_stage_1(AssetLoader& asset_loader) const -> AsyncExec::Stage {
+	auto ret = AsyncExec::Stage{};
+	for (auto const& emitter : m_emitters) { ret.push_back(asset_loader.make_load_particle_emitter(emitter)); }
+	return ret;
+}
+} // namespace spaced

src/spaced/spaced/game/asset_list.hpp

@@ -0,0 +1,44 @@
+#pragma once
+#include <bave/loader.hpp>
+#include <spaced/async_exec.hpp>
+#include <spaced/game/world_spec.hpp>
+#include <spaced/services/services.hpp>
+#include <set>
+
+namespace spaced {
+struct Resources;
+class AssetLoader;
+
+class AssetList {
+  public:
+	explicit AssetList(bave::Loader loader, Services const& services);
+
+	auto add_texture(std::string uri, bool mip_map = false) -> AssetList&;
+	auto add_font(std::string uri) -> AssetList&;
+	auto add_particle_emitter(std::string uri) -> AssetList&;
+
+	auto read_world_spec(std::string_view uri) -> WorldSpec;
+
+	[[nodiscard]] auto build_task_stages() const -> std::vector<AsyncExec::Stage>;
+
+  private:
+	struct Tex {
+		std::string uri{};
+		bool mip_map{};
+
+		// MacOS doesn't provide operator<=> for strings :/
+		auto operator==(Tex const& rhs) const -> bool { return uri == rhs.uri; }
+		auto operator<(Tex const& rhs) const -> bool { return uri < rhs.uri; }
+	};
+
+	auto build_stage_0(AssetLoader& asset_loader) const -> AsyncExec::Stage;
+	auto build_stage_1(AssetLoader& asset_loader) const -> AsyncExec::Stage;
+
+	bave::Loader m_loader;
+	bave::NotNull<Resources*> m_resources;
+
+	std::set<Tex> m_textures{};
+	std::set<std::string> m_fonts{};
+	std::set<std::string> m_emitters{};
+};
+} // namespace spaced