njin_anim.h

#pragma once
#include "_math.h"
#include "_types.h"
#include <array>
#include <vector>
 
namespace njin {
struct context;


enum anim_direction {
  anim_forward,           
  anim_reverse,           
  anim_ping_pong,         
  anim_ping_pong_reverse, 
};

struct anim_clip_desc {
  const char *name = nullptr; 
  i32 from = 0;               
  i32 to = 0;                 
  anim_direction direction = anim_forward; 
  i32 repeat = 0;
};

anim_sheet_handle anim_sheet_load(context &ctx, const char *json_path);

anim_sheet_handle anim_sheet_grid(context &ctx, texture_handle texture,
                                  vec2 frame_size, f32 fps);

bool anim_sheet_add_clip(context &ctx, anim_sheet_handle sheet,
                         const anim_clip_desc &desc);

void anim_sheet_unload(context &ctx, anim_sheet_handle sheet);

i32 anim_clip_find(const context &ctx, anim_sheet_handle sheet,
                   const char *name);

f32 anim_clip_duration(const context &ctx, anim_sheet_handle sheet,
                       const char *name);

enum anim_cmp {
  anim_gt,      
  anim_lt,      
  anim_ge,      
  anim_le,      
  anim_eq,      
  anim_ne,      
  anim_true,    
  anim_false,   
  anim_trigger,
};

struct anim_cond {
  const char *param = nullptr; 
  anim_cmp cmp = anim_true;    
  f32 value = 0.0f;            
};

struct anim_state_desc {
  const char *name = nullptr; 
  const char *clip = nullptr; 
  f32 speed = 1.0f;           
  i32 repeat = -1;
};

struct anim_transition_desc {
  const char *from = nullptr;
  const char *to = nullptr; 
  std::vector<anim_cond> when{}; 
  bool after_finish = false;
};

struct anim_graph_desc {
  anim_sheet_handle sheet{}; 
  std::vector<anim_state_desc> states{}; 
  std::vector<anim_transition_desc> transitions{}; 
  const char *start = nullptr; 
};

inline constexpr i32 anim_max_params = 16;

anim_graph_handle anim_graph_create(context &ctx, const anim_graph_desc &desc);

struct animator {
  anim_graph_handle graph{}; 
  anim_sheet_handle sheet{}; 
  f32 speed = 1.0f;          
  bool playing = true;       

  i32 state = -1;  
  i32 clip = -1;   
  i32 frame = -1;  
  i32 step = 0;    
  f32 time = 0.0f; 
  f32 state_time = 0.0f; 
  i32 loops = 0;   
  i32 repeat = 0;  
  bool finished = false; 
  std::array<f32, anim_max_params> params{}; 
};

bool animator_play(const context &ctx, animator &anim, const char *name,
                   bool restart = false);

void animator_set(const context &ctx, animator &anim, const char *param,
                  f32 value);

void animator_set_bool(const context &ctx, animator &anim, const char *param,
                       bool value);

void animator_trigger(const context &ctx, animator &anim, const char *param);

bool animator_in(const context &ctx, const animator &anim, const char *name);

const char *animator_current(const context &ctx, const animator &anim);
} // namespace njin