168 |
* expression's constant value may be evaluated already at script |
* expression's constant value may be evaluated already at script |
169 |
* parse time, which may result in performance benefits during script |
* parse time, which may result in performance benefits during script |
170 |
* runtime. |
* runtime. |
171 |
|
* |
172 |
|
* @b NOTE: A constant expression is per se always also non modifyable. |
173 |
|
* But a non modifyable expression may not necessarily be a constant |
174 |
|
* expression! |
175 |
|
* |
176 |
|
* @see isModifyable() |
177 |
*/ |
*/ |
178 |
virtual bool isConstExpr() const = 0; |
virtual bool isConstExpr() const = 0; |
179 |
|
|
180 |
|
/** |
181 |
|
* Returns true in case this expression is allowed to be modified. |
182 |
|
* If this method returns @c false then this expression must be handled |
183 |
|
* as read-only expression, which means that assigning a new value to it |
184 |
|
* is either not possible or not allowed. |
185 |
|
* |
186 |
|
* @b NOTE: A constant expression is per se always also non modifyable. |
187 |
|
* But a non modifyable expression may not necessarily be a constant |
188 |
|
* expression! |
189 |
|
* |
190 |
|
* @see isConstExpr() |
191 |
|
*/ |
192 |
bool isModifyable() const; |
bool isModifyable() const; |
193 |
}; |
}; |
194 |
|
|
468 |
struct VMRelPtr { |
struct VMRelPtr { |
469 |
void** base; ///< Base pointer. |
void** base; ///< Base pointer. |
470 |
int offset; ///< Offset (in bytes) relative to base pointer. |
int offset; ///< Offset (in bytes) relative to base pointer. |
471 |
|
bool readonly; ///< Whether the pointed data may be modified or just be read. |
472 |
}; |
}; |
473 |
|
|
474 |
/** @brief Pointer to built-in VM integer variable (of C/C++ type int). |
/** @brief Pointer to built-in VM integer variable (of C/C++ type int). |
496 |
VMIntRelPtr() { |
VMIntRelPtr() { |
497 |
base = NULL; |
base = NULL; |
498 |
offset = 0; |
offset = 0; |
499 |
|
readonly = false; |
500 |
} |
} |
501 |
VMIntRelPtr(const VMRelPtr& data) { |
VMIntRelPtr(const VMRelPtr& data) { |
502 |
base = data.base; |
base = data.base; |
503 |
offset = data.offset; |
offset = data.offset; |
504 |
|
readonly = false; |
505 |
} |
} |
506 |
virtual int evalInt() { return *(int*)&(*(uint8_t**)base)[offset]; } |
virtual int evalInt() { return *(int*)&(*(uint8_t**)base)[offset]; } |
507 |
virtual void assign(int i) { *(int*)&(*(uint8_t**)base)[offset] = i; } |
virtual void assign(int i) { *(int*)&(*(uint8_t**)base)[offset] = i; } |
584 |
#define DECLARE_VMINT(basePtr, T_struct, T_member) ( \ |
#define DECLARE_VMINT(basePtr, T_struct, T_member) ( \ |
585 |
(VMRelPtr) { \ |
(VMRelPtr) { \ |
586 |
(void**) &basePtr, \ |
(void**) &basePtr, \ |
587 |
offsetof(T_struct, T_member) \ |
offsetof(T_struct, T_member), \ |
588 |
|
false \ |
589 |
} \ |
} \ |
590 |
) \ |
) \ |
591 |
|
|
592 |
|
/** |
593 |
|
* Same as DECLARE_VMINT(), but this one defines the VMIntRelPtr and |
594 |
|
* VMInt8RelPtr structures to be of read-only type. That means the script |
595 |
|
* parser will abort any script at parser time if the script is trying to |
596 |
|
* modify such a read-only built-in variable. |
597 |
|
* |
598 |
|
* @b NOTE: this is only intended for built-in read-only variables that |
599 |
|
* may change during runtime! If your built-in variable's data is rather |
600 |
|
* already available at parser time and won't change during runtime, then |
601 |
|
* you should rather register a built-in constant in your VM class instead! |
602 |
|
* |
603 |
|
* @see ScriptVM::builtInConstIntVariables() |
604 |
|
*/ |
605 |
|
#define DECLARE_VMINT_READONLY(basePtr, T_struct, T_member) ( \ |
606 |
|
(VMRelPtr) { \ |
607 |
|
(void**) &basePtr, \ |
608 |
|
offsetof(T_struct, T_member), \ |
609 |
|
true \ |
610 |
|
} \ |
611 |
|
) \ |
612 |
|
|
613 |
/** @brief Built-in VM 8 bit integer array variable. |
/** @brief Built-in VM 8 bit integer array variable. |
614 |
* |
* |
615 |
* Used for defining built-in integer array script variables (8 bit per |
* Used for defining built-in integer array script variables (8 bit per |