Preprocessor Directives

Preprocessor directives are special language constructs, which control the script interpreter behavior. All UnigineScript directives begin with the # sign, and each of them should be on its own line. Note that there are no semicolons at the end of strings that start with directives.

A macro is a fragment of code which has been given a name. Whenever the name is used, it is replaced by the contents of the macro.

There is a pre-defined set of macros:

• __VERSION__ - the UnigineScript interpreter version, for example, "1.82".
• NDEBUG - the binary does not contain debugging information (release build).
• _WIN32 - target operating system is Windows.
• _LINUX - target operating system is Linux.
• _MACOS - target operating system is Mac OS X.
• _ARCH_X86 - target operating system version is 32-bit.
• _ARCH_X64 - target operating system version is 64-bit.
• HAS_BLOB - Blob class is available in the Core Library.
• HAS_BOUNDS - Bounds-related classes are available in the Core Library.
• HAS_DIRECT3D11 - the binary is built with Direct3D 11 rendering system.
• HAS_JOYSTICK - the binary is built with support of a joystick.
• HAS_IMAGE - Image class is available in the Core Library.
• HAS_MESH - Mesh class is available in the Core Library.
• HAS_MEMORY - the binary is built with Unigine memory management system.
• HAS_OPENAL - the binary is built with OpenAL sound system.
• HAS_OPENGL - the binary is built with OpenGL rendering system.
• HAS_OPENEXR - the binary is built with support of the OpenEXR format.
• HAS_PATH - Path class is available in the Core Library.
• HAS_REGEXP - Regexp Class is available in the Core Library.
• HAS_SIXAXIS - the binary is built with support of a sixaxis controller.
• HAS_SOCKET - Socket Class is available in the Core Library.
• HAS_XAUDIO2 - the binary is built with XAudio2 sound system.
• HAS_XML - Xml Class is available in the Core Library.
• HAS_XPAD360 - the binary is built with support of Xbox 360 gamepad.
• USE_DOUBLE - the binary is built with support of double precision of coordinates.

These macros can be used as conditions and combined with logical operators: () for grouping, || for "or", && for "and".

Loads the content of a given file.

Syntax: #include "someFile"

Here someFile is a target file name.

#include "foo.h"
foo(); // ok if foo.h contains declaration of foo()

To avoid conflicts it's recommended to include files this way:

#ifndef __MYLIB_H__
#define __MYLIB_H__

#include "myLib.h"

#endif /* __MYLIB_H__ */

Sets an identifier and a character sequence, by which the identifier will be replaced in the text of the program.

Syntax: #define macro_name character_sequence

Here macro_name will be replaced with character_sequence everywhere in the code. Note that character_sequence shouldn't contain spaces (except for strings, which must be enclosed in double quotes) and can be omitted.

#define LEFT 1
#define RIGHT 0

log.message("%d %d\n",LEFT,RIGHT);
// Output: 1 0

#define FRUIT "an apple"

log.message("%s\n", "today we will eat "FRUIT);
// Output: today we will eat an apple

// arguments are also supported:
#define saturate(v) clamp(v,0.0,1.0)

Inside the #define directive, the literal # operator can be used. It turns a macro argument into a string constant. This operator can also be used inside templates.

Syntax: #macro_arg

Here macro_arg is an argument to a macro.

#define assert(EXP) { if(EXP) { } else { throw("Assertion: '%s'",#EXP); } }

See also Templates.

Removes a previously defined identifier.

Syntax: #undef macro_name

#define LOCK
#undef LOCK

#ifndef LOCK
log.message("unlocked\n"); // this fragment will be executed
#endif

Allows executing some fragment of code conditionally, if a given identifier is defined with #define.

Syntax: #ifdef macro_name
some_code #endif

If macro_name is defined, then some_code will be executed.

#define LOCK1
#define LOCK2

#ifdef (LOCK1 && LOCK2) || LOCK3
log.message("locked\n"); // this fragment will be executed
#endif

Allows executing some fragment of code conditionally, if a given identifier is not defined with #define or is undefined with #undef.

Syntax: #ifndef macro_name
some_code #endif

If macro_name is not defined, then some_code will be executed.

#define LOCK

#ifndef LOCK
log.message("unlocked\n"); // this fragment will NOT be executed
#endif

Creates an alternative to #ifdef and #ifndef pragmas.

Syntax: #ifdef macro_name some_code
#else some_more_code
#endif

Here #ifndef can be used instead of #ifdef (however, the meaning of the condition will be reversed). If the first condition is false, then everything from the first #else up to the first #endif will be executed.

#define SOUND_ENABLE

#ifdef SOUND_ENABLE
log.message("sound enabled\n");
#else
log.message("sound disabled\n"); // this fragment will be executed
#endif

Create a conditional alternative to #ifdef and #ifndef pragmas.

Syntax: #ifdef macro_name1 some_code1
#elif macro_name2 some_code2
#endif

Here #ifndef can be used instead of #ifdef (however, the meaning of the condition will be reversed). If macro_name1 is false, then macro_name2 is tested, and if it's true, everything from this #elif up to the first #elif, #else or #endif will be executed.

#define VAL2

#ifdef VAL1
log.message("it is 1\n");
#elif VAL2
log.message("it is 2\n"); // this fragment will be executed
#elif VAL3
log.message("it is 3\n");
#endif

Marks an end of conditional compilation.

Terminates execution of the script and logs the message into the console and a system log file.

Syntax: #error message_text

#error I don't want to execute it any longer

Logs the message into the console and a system log file, the script continues execution.

Syntax: #warning message_text

#warning There is somethings wrong in here

Terminates compilation if a variable of a long type is used in the script, and logs the error message into the console and a system log file.

Terminates compilation if a variable of a double type is used in the script, and logs the error message into the console and a system log file.

Replaces all variables of a long type in the script with an int type.

Replaces all variables of a double type in the script with a float type.