Processing: Creative Coding and Computational Art

this.salsaTemperature+" alarm salsa.");
}
}
else {
println("Uh, you'll need to give me some ingredients\n" + ➥
"if you actually want me to produce a recipe.");
}
// go to next line after printing
// cooking instructions to the screen
println();
}
}
There are a couple of ways of using a class in Processing. For one, you can simply add it in
your main tab with the rest of your sketch code, just as you’ve been doing with functions.
(To use a custom class or function, you must also include Processing’s setup() function.)
You can also enter a class (or function) in a separate tab. The sketch will still see it/treat it
as if it exists in the main tab. Finally, you can also work in Java mode, which I’ll cover in
Chapter 14. For the BurritoRecipe example, I used the simplest solution, and just entered
the class code directly below the setup() function. At the top of the sketch, within
the setup() function, I instantiated three BurritoRecipe objects, and called the
printRecipe() method for each of them. When the sketch runs, it outputs burrito
cooking directions, based on the arguments I passed when I instantiated the three
BurritoRecipe objects.
In the first instantiation statement, I didn’t pass any arguments:
BurritoRecipe b1 = new BurritoRecipe();
The printRecipe() method outputs the following:
Burrito Recipe:
---------------
Uh, you'll need to give me some ingredients
if you actually want me to produce a recipe.
In the second instantiation statement, I passed three arguments:
BurritoRecipe b2 = new BurritoRecipe ("spinach", "black", "chicken");
The printRecipe() method outputs the following:
Burrito Recipe:
---------------
Steam or lightly pan heat a spinach tortilla.
Sauté fresh onions, garlic, cilantro, slowly mixing in black beans ➥
and white wine.
Grill chicken along with fresh green pepper, jalapeno pepper, ➥
chile pepper, onions and garlic.
OBJECT-ORIENTED PROGRAMMING
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