// semantic names
typedef enum {
    V_POSITION,
    V_NORMAL,
    V_TANGENT,
    V_BITANGENT,
    V_TEXCOORD,
    V_BLEND_INDICES,
    V_BLEND_WEIGHTS,
    V_UNKNOWN,
    V_COUNT = V_UNKNOWN
} VertexSemantic;

typedef enum {
    SIGN_BIT = 31,
    FORMAT = 30,
    // Bit range 20-29 unused
    BITS_W = 15,
    BITS_Z = 10,
    BITS_Y = 5,
    BITS_X = 0
} FormatEncoding;

typedef enum {
    FLOAT,
    INTEGER
} ComponentType;

// helper functions for encoding / decoding Format
inline uint32_t format(ComponentType type, bool signed_, uint8_t bit_depth_x, uint8_t bit_depth_y, uint8_t bit_depth_z, uint8_t bit_depth_w) {
    return ((uint8_t)signed_) << SIGN_BIT | ((uint8_t)type) << FORMAT | bit_depth_x << BITS_X | bit_depth_y << BITS_Y | bit_depth_z << BITS_Z | bit_depth_w << BITS_W;
}

inline uint32_t bits(uint32_t format) {
    return ((format >> BITS_X) & 0x1f) + ((format >> BITS_Y) & 0x1f) + ((format >> BITS_Z) & 0x1f) + ((format >> BITS_W) & 0x1f);
}

struct VertexBufferView {
    typedef enum { MAX_CHANNELS = 16 };
    struct Channel {
        uint32_t format;
        uint8_t semantic;
        uint8_t stream;
        uint8_t set;
        bool instance;
    } channels[MAX_CHANNELS];
    uint32_t n_channels;
};

struct IndexBufferView {
    // either 2 or 4 depending on if index buffer is 32
    uint8_t stride;
};

struct RenderBufferApi
{
    typedef uint32_t Handle;

    typedef enum { VERTEX_BUFFER_VIEW, INDEX_BUFFER_VIEW } View;
    typedef enum { STATIC, UPDATABLE } Validity;

    Handle (*create_buffer)(uint32_t size, Validity validity, View view, const void *view_desc, const void *data = nullptr);
    void (*update_buffer)(Handle handle, uint32_t size, const void *data = nullptr);
    void (*destroy_buffer)(Handle handle);
}: