USC Interpreter
The stand-alone interpreter (called USC due to its script file extension) enables to make Unigine scripts into executable programs (USC scripts) that are run directly from the environment or from the command-line. As the USC interpreter works independently, it offers an easy way for developers to extend the functionality and solve the specific or recurring tasks for which it is not necessary to create a separate executable application.
Source code of the USC interpreter can be found under <UnigineSDK>/source/tools/Interpreter.
Available Functionality
The USC interpreter provides the following functionality:
Core library | You can use the USC interpreter for reading/writing files, parsing XML files, handling images, performing mathematical calculations and so on as the USC interpreter includes the core library. |
---|---|
Static and skinned meshes | You can load and save both the static and skinned meshes, modify or clear all their data. You can add and set transformation to mesh surfaces, add animations and bones (if you handle a skinned mesh), change position, normal vectors and texture coordinates for separate vertices and so on. See the Mesh class for available functions. |
Paths | You can load, manipulate and save paths. See the Path class for available functions. |
Command line arguments | You can pass any number of arguments to the executable script via the command line and process them in this script. See examples below. |
Logging | You can print notification messages, warnings and errors to track progress of script execution, if necessary. |
The described functionality is used to implement USC scripts.
Command-Line Options
USC interpreter recognizes the following command-line option:
- -define DEFINE_NAME - pass an external definition (#DEFINE) to the USC interpreter. You should specify this option after a USC script in the command prompt (terminal).
usc_x64.exe my_script.usc -define PRINT_MSG
Implementing USC Script
To implement a USC script (written in UnigineScript) that should be run by the USC interpreter, use main() function as an entry point:
void main() {
// put your code here
}
Then you should save the script with the *.usc extension and run it by the USC interpreter.
If you pass command-line arguments to the script, you should implement parsing logic for them. Otherwise, they won't affect the script behavior.
- int getNumArgs () - returns the number of command line arguments.
- string getArg (int num) - returns a command line argument by its number.
Parsing Passed Command-Line Arguments
The following example demonstrates how to assign values of the command-line arguments to the script variables:
#!/usr/bin/env usc
// declare variables
int value1 = 0;
int value2 = 0;
/*
*/
void main() {
// parce arguments
for(int i = 0; i < getNumArgs(); i++) {
// get the argument value
string arg = getArg(i);
// process all required arguments
if(arg == "-set_value_1") {
if(i + 1 >= getNumArgs()) {
continue;
}
// assign an argument value to the variable
value1 = int(getArg(++i));
continue;
}
if(arg == "-set_value_2") {
if(i + 1 >= getNumArgs()) {
continue;
}
// assign an argument value to the variable
value2 = int(getArg(++i));
continue;
}
}
// print the variables
log.message("value1: %d\nvalue2: %d\n",value1,value2);
}
usc_x64.exe my_script.usc -set_value_1 3 -set_value_2 7
value1: 3
value2: 7
Printing All Command-line Arguments
The following example demonstrates how to print all command-line arguments passed to the USC script:
#!/usr/bin/env usc
void main() {
forloop(int i = 0; getNumArgs()) {
log.message("Arg [%d]: %s\n",i,getArg(i));
}
}
usc_x64.exe my_script.usc -arg1 -arg2
Arg [0]: my_script.usc
Arg [1]: -arg1
Arg [2]: -arg2
See Also
For more examples see the *.usc scripts in the following folders:
- <UnigineSDK>/utils/Upgrade
- <UnigineSDK>/source/tools/Interpreter/scripts (available only in the full source version of UNIGINE SDK)
Running USC Script
The USC scripts are run by the USC interpreter.
Running USC on Windows
To run a USC script on Windows:
- Add a path to <UnigineSDK>/bin/usc_*.exe binary executable to environment variables. Depending on the postfix, it can be either 32-bit (_86) or 64-bit, debug (d) or release (no postfix) version of the USC interpreter.
You can also associate the *.usc file with the <UnigineSDK>/bin/usc_*.exe binary executable. In this case, you will run the script by double-clicking it.
- In the command prompt, go to the folder with the *.usc file and run it by the USC interpreter with all required arguments, for example:
C:\Windows\system32>d: D:\>cd my_project\usc_scripts D:\my_project\usc_scripts>usc_x64.exe my_script.usc -define USE_DEFINE -arg1 4
Running USC on Linux
To run a USC script on Linux, follow the instructions:
- In the first line of your script, specify the following:
#!/usr/bin/env usc
- Add a path to the <UnigineSDK>/bin/usc_* binary executable to environment variables. Depending on the postfix, you can use either 32-bit (_86) or 64-bit, debug (d) or release (no postfix) version of the USC interpreter.
Make sure that your terminal takes environment variables into account.
- In the terminal, go to the folder with the *.usc file and run it by the USC interpreter with all required arguments, for example:
On Linux:
username@pc-name:~$ cd my_project/usc_script username@pc-name:~/my_project/usc_script$ usc_x64 my_script.usc