cell/source/qjs_transform.c

#include "jsffi.h"
#include "qjs_macros.h"
#include "stb_ds.h"

#include "transform.h"
#include "HandmadeMath.h"
#include "cell.h"

// Transform class definitions
JSClassID js_transform_id;
static void js_transform_mark(JSRuntime *rt, JSValueConst val, JS_MarkFunc *mark_func) {
  transform *t = JS_GetOpaque(val, js_transform_id);
  if (!t) return;
  // Mark the JSValue references stored in your struct
  JS_MarkValue(rt, t->change_hook, mark_func);
  JS_MarkValue(rt, t->jsparent, mark_func);
  // Mark the array elements
  for (int i = 0; i < arrlen(t->jschildren); i++)
    JS_MarkValue(rt, t->jschildren[i], mark_func);
}

QJSCLASSMARK_EXTERN(transform,)

// TRANSFORM GETTER/SETTER FUNCTIONS
JSC_GETSET_APPLY(transform, pos, vec3)
JSC_GETSET_APPLY(transform, scale, vec3)
JSC_GETSET_APPLY(transform, rotation, quat)

static JSValue js_transform_get_change_hook(JSContext *js, JSValueConst self)
{
  transform *t = js2transform(js,self);
  return JS_DupValue(js,t->change_hook);
}

static JSValue js_transform_set_change_hook(JSContext *js, JSValueConst self, JSValue v)
{
  transform *t = js2transform(js,self);
  if (!JS_IsNull(v) && !JS_IsFunction(js,v)) return JS_ThrowReferenceError(js, "Hook must be a function.");
  JS_FreeValue(js,t->change_hook);
  t->change_hook = JS_DupValue(js,v);
  return JS_NULL;
}

static JSValue js_transform_get_parent(JSContext *js, JSValueConst self)
{
  transform *t = js2transform(js,self);
  if (t->parent) return JS_DupValue(js,t->jsparent);
  return JS_NULL;
}

static JSValue js_transform_set_parent(JSContext *js, JSValueConst self, JSValue v)
{
  transform *p = js2transform(js,v);
  if (!JS_IsNull(v) && !p)
    return JS_ThrowReferenceError(js,"Parent must be another transform.");

  transform *t = js2transform(js,self);

  if (t == p)
    return JS_ThrowReferenceError(js, "A transform cannot be its own parent.");

  if (t->parent) {
    transform *cur_parent = t->parent;
    JS_FreeValue(js,t->jsparent);
    t->jsparent = JS_NULL;

    for (int i = 0; i < arrlen(cur_parent->children); i++) {
      if (cur_parent->children[i] == t) {
        arrdelswap(cur_parent->children,i);
        break;
      }
    }

    for (int i = 0; i < arrlen(cur_parent->jschildren); i++) {
      if (JS_SameValue(js,cur_parent->jschildren[i],self)) {
        JS_FreeValue(js,cur_parent->jschildren[i]);
        arrdelswap(cur_parent->jschildren,i);
        break;
      }
    }
  }

  t->parent = p;
  t->jsparent = JS_DupValue(js,v);

  if (p) {
    arrput(p->children, t);
    JSValue child = JS_DupValue(js,self);
    arrput(p->jschildren,child);
  }

  transform_apply(t);
    
  return JS_NULL;
}

// TRANSFORM ACTION FUNCTIONS

JSC_CCALL(transform_move,
  transform *t = js2transform(js,self);
  transform_move(t, js2vec3(js,argv[0]));
)

JSC_CCALL(transform_lookat,
  HMM_Vec3 point = js2vec3(js,argv[0]);
  transform *go = js2transform(js,self);
  HMM_Mat4 m = HMM_LookAt_RH(go->pos, point, vUP);
  go->rotation = HMM_M4ToQ_RH(m);
  transform_apply(go);
)

JSC_CCALL(transform_rotate,
  HMM_Vec3 axis = js2vec3(js,argv[0]);
  transform *t = js2transform(js,self);
  HMM_Quat rot = HMM_QFromAxisAngle_RH(axis, js2angle(js,argv[1]));
  t->rotation = HMM_MulQ(t->rotation,rot);
  transform_apply(t);
)

JSC_CCALL(transform_angle,
  HMM_Vec3 axis = js2vec3(js,argv[0]);
  transform *t = js2transform(js,self);
  if (axis.x) return angle2js(js,HMM_Q_Roll(t->rotation));
  if (axis.y) return angle2js(js,HMM_Q_Pitch(t->rotation));
  if (axis.z) return angle2js(js,HMM_Q_Yaw(t->rotation));
  return angle2js(js,0);
)

JSC_CCALL(transform_direction,
  transform *t = js2transform(js,self);
  return vec32js(js, HMM_QVRot(js2vec3(js,argv[0]), t->rotation));
)

JSC_CCALL(transform_phys2d,
  transform *t = js2transform(js,self);
  HMM_Vec2 v = js2vec2(js,argv[0]);
  float av = js2number(js,argv[1]);
  float dt = js2number(js,argv[2]);
  transform_move(t, (HMM_Vec3){v.x*dt,v.y*dt,0});
  HMM_Quat rot = HMM_QFromAxisAngle_RH((HMM_Vec3){0,0,1}, av*dt);
  t->rotation = HMM_MulQ(t->rotation, rot);
  transform_apply(t);
)

JSC_CCALL(transform_unit,
  transform *t = js2transform(js,self);
  t->pos = v3zero;
  t->rotation = QUAT1;
  t->scale = v3one;
  transform_apply(t);
)

JSC_CCALL(transform_trs,
  transform *t = js2transform(js,self);
  t->pos = JS_IsNull(argv[0]) ? v3zero : js2vec3(js,argv[0]);
  t->rotation = JS_IsNull(argv[1]) ? QUAT1 : js2quat(js,argv[1]);
  t->scale = JS_IsNull(argv[2]) ? v3one : js2vec3(js,argv[2]);
  transform_apply(t);
)

JSC_CCALL(transform_rect,
  transform *t = js2transform(js,self);
  rect r = js2rect(js,argv[0]);
  t->pos = (HMM_Vec3){r.x,r.y,0};
  t->scale = (HMM_Vec3){r.w,r.h,1};
  t->rotation = QUAT1;
  transform_apply(t);
)

JSC_CCALL(transform_array,
  transform *t = js2transform(js,self);
  HMM_Mat4 m= transform2mat(t);
  ret = JS_NewArray(js);
  for (int i = 0; i < 16; i++)
    JS_SetPropertyUint32(js,ret,i, number2js(js,m.em[i]));
)

JSC_CCALL(transform_torect,
  transform *t = js2transform(js,self);
  return rect2js(js,transform2rect(t));
)

JSC_CCALL(transform_children,
  transform *t = js2transform(js,self);
  ret = JS_NewArray(js);
  for (int i = 0; i < arrlen(t->jschildren); i++)
    JS_SetPropertyUint32(js,ret,i,JS_DupValue(js,t->jschildren[i]));
)

static const JSCFunctionListEntry js_transform_funcs[] = {
  CGETSET_ADD(transform, pos),
  CGETSET_ADD(transform, scale),
  CGETSET_ADD(transform, rotation),
  CGETSET_ADD(transform, parent),
  CGETSET_ADD(transform, change_hook),
  MIST_FUNC_DEF(transform, trs, 3),
  MIST_FUNC_DEF(transform, phys2d, 3),
  MIST_FUNC_DEF(transform, move, 1),
  MIST_FUNC_DEF(transform, rotate, 2),
  MIST_FUNC_DEF(transform, angle, 1),
  MIST_FUNC_DEF(transform, lookat, 1),
  MIST_FUNC_DEF(transform, direction, 1),
  MIST_FUNC_DEF(transform, unit, 0),
  MIST_FUNC_DEF(transform, rect, 1),
  MIST_FUNC_DEF(transform, array, 0),
  MIST_FUNC_DEF(transform, torect, 0),
  MIST_FUNC_DEF(transform, children, 0),
};

// Constructor function for transform
static JSValue js_transform_constructor(JSContext *js, JSValueConst new_target, int argc, JSValueConst *argv) {
  transform *t = make_transform();
  if (!t) return JS_ThrowOutOfMemory(js);
  
  JSValue ret = transform2js(js, t);
  t->self = ret;
  
  return ret;
}

JSC_CCALL(transform_clean,
  clean_all(js);
)

static const JSCFunctionListEntry js_transform_ctor_funcs[] = {
  MIST_FUNC_DEF(transform, clean, 0),
};

JSValue js_transform_use(JSContext *js) {
  // Register the transform class
  QJSCLASSPREP_FUNCS(transform);
  
  // Create the constructor function
  JSValue ctor = JS_NewCFunction2(js, js_transform_constructor, "transform", 0, JS_CFUNC_constructor, 0);
  
  // Set the prototype on the constructor
  JSValue proto = JS_GetClassProto(js, js_transform_id);
  JS_SetConstructor(js, ctor, proto);
  JS_FreeValue(js, proto);
  
  // Add static methods to the constructor
  JS_SetPropertyFunctionList(js, ctor, js_transform_ctor_funcs, countof(js_transform_ctor_funcs));
  
  return ctor;
}