4 files changed, 88 insertions, 0 deletions
diff --git a/src/doc/internal/component.dox b/src/doc/internal/component.dox
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+// vim:ft=doxygen
+namespace crepe {
+/**
+
+\defgroup internal_component Components
+\ingroup internal
+\brief ECS Components
+
+Components are attached to GameObject instances and are composed by the game
+programmer to create specific entities in the game world. While they are
+implemented as C++ classes, components should be treated as C-style structs,
+meaning all members are public and they do not contain functions.
+
+A basic component has the following structure:
+```cpp
+#include <crepe/Component.h>
+
+class MyComponent : public crepe::Component {
+public:
+	// Add your custom component's ininitializer properties after the `id`
+	// parameter. The first parameter is controlled by GameObject::add_component,
+	// while all other parameters are forwarded using std::forward.
+	MyComponent(game_object_id_t id, ...);
+
+	// Optionally define the `get_instances_max` method to limit the amount of
+	// instances of this component per GameObject. The default implementation for
+	// this function returns -1, which means the instance count does not have an
+	// upper limit:
+	virtual int get_instances_max() const { return -1; }
+
+	// Properties
+	// ...
+};
+```
+
+Generally, components are "handled" by \ref internal_system "systems", which may
+optionally change the components' state. Components' state may also be
+controlled by the game programmer through \ref feature_script "scripts".
+
+*/
+}
diff --git a/src/doc/internal/resource.dox b/src/doc/internal/resource.dox
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+++ b/src/doc/internal/resource.dox
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+// vim:ft=doxygen
+namespace crepe {
+/**
+
+\defgroup internal_resource Resources
+\ingroup internal
+\brief Concrete resources
+
+\todo This section is incomplete
+
+*/
+}
diff --git a/src/doc/internal/style.dox b/src/doc/internal/style.dox
new file mode 100644
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+++ b/src/doc/internal/style.dox
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+// vim:ft=doxygen
+/**
+
+\defgroup internal_style Code style
+\ingroup internal
+\brief Coding conventions
+\include{doc} contributing.md
+
+*/
diff --git a/src/doc/internal/system.dox b/src/doc/internal/system.dox
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+++ b/src/doc/internal/system.dox
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+// vim:ft=doxygen
+namespace crepe {
+/**
+
+\defgroup internal_system Systems
+\ingroup internal
+\brief ECS Systems
+
+\todo This section is incomplete
+
+A system is responsible for processing the data stored in \ref
+internal_component "components".
+
+A basic system has the following structure:
+```cpp
+#include <crepe/system/System.h>
+
+class MySystem : public System {
+public:
+	using System::System;
+	void update() override;
+};
+```
+
+*/
+}