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README.md

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+# shoal
+
 my silly little ecs engine for odin and raylib :3
+
+## usage
+first create a new app struct. this is where your systems and plugins live.
+
+```odin
+import ecs "shoal/src"
+
+app: ecs.App
+```
+
+you can run your app with `run()`. run takes a reference to your app to run it's systems.
+
+``` odin
+main :: proc() {
+  ecs.run(&app)
+}
+```
+
+### component
+components are just structs with data, and kept with other components of that type in `Storage`.
+create a new component
+
+```odin
+ExampleComponent :: struct {}
+```
+
+and create it's storage
+
+```odin
+Example: ecs.Storage(ExampleComponent)
+```
+
+### spawn entities
+create a new entity with `spawn_entity()`
+
+```odin
+main :: proc() {
+  entity := ecs.spawn_entity(&app)
+}
+
+```
+
+and give it new components with `add_component()`
+
+```odin
+main :: proc() {
+  ecs.add_component(entity, &Example) // make sure to pass a reference to the storage, not the component type
+}
+```
+
+### query
+since components are saved in storage next to their entity, you can loop through a Storage and pick out what you like
+
+```odin
+main :: proc() {
+  for entity_id, component in ecs.slice(&Example) {
+    //...
+  }
+}
+```
+
+or if you know your storage only has one entry use `single()`
+
+```odin
+main :: proc() {
+  entity_id, component := ecs.single(&Example)
+}
+```