Zelda64Recomp/patches/transform_ids.h

#ifndef __TRANSFORM_IDS_H__
#define __TRANSFORM_IDS_H__

#define CAMERA_TRANSFORM_ID_START 0x10U

#define SKYBOX_TRANSFORM_ID_START 0x100U

#define PARTICLE_TRANSFORM_ID_START 0x200U

#define SOARING_WINGS_TRANSFORM_ID 0x300U
#define SOARING_CAPSULE_TRANSFORM_ID 0x301U

#define BOWSTRING_TRANSFORM_ID 0x400U

#define ACTOR_TRANSFORM_LIMB_COUNT 128
#define ACTOR_TRANSFORM_ID_COUNT (ACTOR_TRANSFORM_LIMB_COUNT * 2) // One ID for each limb and another for each post-draw
#define ACTOR_TRANSFORM_ID_START 0x1000000U

// Use 16 bits of compiler-inserted padding to hold the actor's transform ID.
// 0x22 between halfDaysBits and world
#define actorIdByte0(actor) ((u8*)(actor))[0x22]
// 0x23 between halfDaysBits and world
#define actorIdByte1(actor) ((u8*)(actor))[0x23]

// Other unused padding:
// 0x3A between audioFlags and focus
// 0x3B between audioFlags and focus

static inline u32 actor_transform_id(Actor* actor) {
    u32 actor_id = 
        (actorIdByte0(actor) <<  0) |
        (actorIdByte1(actor) <<  8);

    return (actor_id * ACTOR_TRANSFORM_ID_COUNT) + ACTOR_TRANSFORM_ID_START;
}

#endif