A complete Processing script.

It consists in several parts, most of them optional.

• Preamble: Usually the place where variables are initialized.
• Setup: After running the code in the preamble, the code in this part is executed once.
• Draw: After the setup, this part of the code is executed in loops over and over again.
• MouseClicked: Each time the user clicks, the code here is executed once.

To generate each part of the code, use the ProcM monad and the functions from the Graphics.Web.Processing.Interface module. Then, run runProcM or execProcM to get the code result.

Empty script.

Render a script as a lazy Text.

Render a script using renderScript and write it directly in a file.

A piece of Processing code. The type parameter indicates what the context of the code is. This context will allow or disallow the use of certain commands.

The preamble is the code that is executed at the beginning of the script.

In the setup part, settings like size or frame rate are supplied.

The drawing loop.

Code that is executed when the mouse is clicked.

Code that is executed when the mouse is released.

Code executed when a key is pressed.

Class of Processing value types (Proc_* types).

Proc_* types are types from the world of Processing. Some of them are similar to Haskell types, like Proc_Bool and Bool. However, they are not equal. Proc_* types are instance of Eq. However, you should instead use methods from analog Proc_Eq class. Proc_* types contain expressions instead of values. Think of 2+2 instead of 4. Under this situation, 2+2 /= 3+1, since they are different expressions, even if they evaluate to the same value. Actually, you will get True from the evaluation of 2+2 == 3+1, since the library is smart enough to figure out they are the same value. But, please, don't rely on this. Use the Proc_Eq and Proc_Ord classes instead. They return Processing boolean expressions instead of Bool values. Anyway, the types of the library will try to force you to use Proc_* types everywhere.

The reason this library stores expressions instead of values is that it needs to handle things like 2+x, where x is an unknown value. However, an effort is done to ensure that each expression is reduced to its minimum extension.

Boolean values.

Value of True.

Value of False.

Cast a Bool value.

Negation.

Disjunction.

Conjunction.

Integer numbers.

Cast an Int value.

Cast a Proc_Int to a Proc_Float.

Floating point numbers. The provided Eq instance checks the equality of the internal expression, not the value.

Cast a Float value.

Calculates the floor of a Proc_Float.

Type of characters.

Cast a Char value.

Type of textual values.

Cast a strict Text value.

Type of images.

Eq class for Proc_* values.

Ord class for Proc_* values.

Conditional value.