libakgl/include/akgl/stage.h

#ifndef _STAGE_H_
#define _STAGE_H_

#include <SDL3/SDL.h>
#include <akstdlib.h>

#include <akgl/actor.h>

#define AKGL_STAGE_PARTITION_HORIZONTAL             0
#define AKGL_STAGE_PARTITION_VERTICAL               1
#define AKGL_STAGE_PARTITION_MAXDEPTH               4

typedef struct akgl_BSPContext {
    aksl_TreeNode *left;
    aksl_TreeNode *right;
    aksl_TreeNode *parent;
} akgl_BSPContext;

typedef struct akgl_BSPLeaf {
    SDL_FRect extent;
    aksl_ListNode *actors;
} akgl_BSPLeaf;

// Stages are collections of lights and cameras in a 2D or 3D space wherein actors
// and backgrounds are placed and directed for action.
typedef struct akgl_Stage {
    aksl_TreeNode bsp;
    akgl_BSPLeaf _rootleaf;
    akerr_ErrorContext AKERR_NOIGNORE *(*partition)(struct akgl_Stage *self);
    akerr_ErrorContext AKERR_NOIGNORE *(*partition_actor)(struct akgl_Stage *self, akgl_Actor *actor);
} akgl_Stage;


akerr_ErrorContext AKERR_NOIGNORE *akgl_stage_2d(akgl_Stage *self);
    
// A function to divide the stage into a binary space partition tree with lists of actors in each partition
akerr_ErrorContext AKERR_NOIGNORE *akgl_stage_2d_partition(akgl_Stage *self);
akerr_ErrorContext AKERR_NOIGNORE *akgl_stage_2d_partition_switchdirection(uint8_t direction, uint8_t *dest);
akerr_ErrorContext AKERR_NOIGNORE *akgl_stage_2d_bsp_actoriter(aksl_ListNode *node, void *data);
akerr_ErrorContext AKERR_NOIGNORE *akgl_stage_2d_bsp(aksl_TreeNode *root, aksl_ListNode *actors, SDL_FRect extents, uint8_t direction, uint8_t depth, uint8_t maxdepth);
akerr_ErrorContext AKERR_NOIGNORE *akgl_stage_2d_bspfree(akgl_Stage *self);
akerr_ErrorContext AKERR_NOIGNORE *akgl_stage_2d_partition(akgl_Stage *self);
akerr_ErrorContext AKERR_NOIGNORE *akgl_stage_2d_bsp_move(akgl_Stage *self, akgl_Actor *actor);

#endif // _STAGE_H_