Fundamental Notes on Vector Expression Language - VEX coding in Houdini

Basics:  

So you want to learn VEX! 

VEX can be a powerful tool to achieve complex effects in Houdini. Here are some tips to get started:

1. Start with the basics: Begin with understanding basic programming concepts such as variables, data types, and control flow. Once you have a good grasp of these, move on to learning VEX-specific concepts such as vectors, matrices, and functions.

2. Learn by doing: Practice is the key to mastering any programming language. Start with small projects and gradually move on to more complex ones. Houdini provides a number of tutorials and example files that can help you get started.

3. Use the Houdini documentation: Houdini has extensive documentation on VEX that can be accessed through the Help menu. You can also access it online at https://www.sidefx.com/docs/houdini/vex/index.html.

4. Join the community: Houdini has a strong community of users who are always willing to help out. Join forums such as the SideFX forum or Reddit's Houdini subreddit to ask questions and learn from other users.

5. Experiment: Don't be afraid to experiment and try out different approaches to achieve your desired effect. VEX can be a powerful tool, and with some creativity, you can achieve some amazing results.

I hope these tips help you get started with learning VEX.

To get you started here are some basics of VEX: 1. Variables: VEX supports different data types such as integers, floats, and vectors. You can declare variables using the `int`, `float`, and `vector` keywords, respectively. For example:

  
   int myInteger = 10;
   float myFloat = 3.14;
   vector myVector = {1, 2, 3};
   
   

2. Operators: VEX supports a variety of operators, including arithmetic, comparison, and logical operators. For example:

   int a = 10;
   int b = 5;
   int c = a + b; // adds a and b and assigns the result to c
   int d = a > b; // assigns 1 to d (true) because a is greater than b
   int e = !d; // assigns 0 to e (false) because !d means not d
   

3. Functions: VEX provides a range of built-in functions that can be used for various tasks, such as math functions, string manipulation, and vector operations. For example:

   float myFloat = 3.14;
   float myAbs = abs(myFloat); // assigns 3.14 to myAbs
   vector myVector = {1, 2, 3};
   vector myNormalizedVector = normalize(myVector); 
   // normalizes the vector and assigns it to myNormalizedVector
  

4. Control Flow: VEX supports if-else statements and loops such as for and while loops. For example:

   int a = 10;
   int b = 5;
   if (a > b) {
       printf("a is greater than b");
   } else {
       printf("a is not greater than b");
   }

   for (int i = 0; i < 10; i++) {
       printf("i is %d", i);
   }
  
  

These are just some of the basics of VEX. As you dive deeper into VEX, you will learn about more advanced concepts such as structs, arrays, and shaders.