some more docs

1 files changed, 38 insertions, 1 deletions

diff --git a/include/celeritas.h b/include/celeritas.h
index 94d08fb..62b3fc3 100644
--- a/include/celeritas.h
+++ b/include/celeritas.h
@@ -117,7 +117,30 @@ void _cel_push_error(int error_code);
 
 // --- Memory facilities: Allocators, helpers
 
-// TODO: Arenas
+/** @brief Fixed-size arena allocator */
+typedef struct fixed_arena {
+  void* storage;
+  size_t size;
+  size_t alignment;
+  int index;
+} fixed_arena;
+
+/** @brief Create a new fixed arena with the provided storage. */
+fixed_arena fixed_arena_new(void* backing_buffer, size_t size, size_t alignment);
+
+/**
+ * @brief Allocates memory on the arena.
+ * 
+ * @param arena
+ * @param size Number of bytes to reserve
+ * @return Pointer to the allocated memory or NULL if there's not enough space 
+ */
+void* fixed_arena_alloc(fixed_arena* arena, size_t size);
+
+/** @brief Clear the arena thereby resetting the index to the start. */
+void fixed_arena_clear(fixed_arena* a);
+
+// TODO: grow arena
 
 // Pool
 typedef struct void_pool_header void_pool_header;  // TODO: change name of this
@@ -143,6 +166,7 @@ void* void_pool_alloc(void_pool* pool, u32* out_raw_handle);
 void void_pool_dealloc(void_pool* pool, u32 raw_handle);
 u32 void_pool_insert(void_pool* pool, void* item);
 
+// Create a pool of objects with type `T`
 #define TYPED_POOL(T, Name)                                                          \
   typedef struct Name##_pool {                                                       \
     void_pool inner;                                                                 \
@@ -520,6 +544,8 @@ typedef struct geometry {
 } geometry;
 
 typedef u32 joint_idx;
+
+/** @brief Bone hierarchy for a mesh */
 typedef struct armature {
 } armature;
 
@@ -555,6 +581,17 @@ void geo_scale_xyz(geometry* geo, vec3 scale_xyz);
 
 // --- Renderer
 
+/**
+ * @brief Reference renderer you can use to draw beautiful 3D worlds.
+ * @details Implements a Forward+ renderer on top of the RAL (Render Abstraction Layer) provided in celeritas-core.
+
+ */
+typedef struct renderer {
+  /* PBR pipeline */
+  pipeline_handle pbr_pipeline;
+  /* CSM pipeline */
+} renderer;
+
 // void renderer_init(renderer* rend);
 // void renderer_shutdown(renderer* rend);