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Which mouse button?

Notice how this program 'nests' the if statements.

• • The first if checks to see if a mouse button is pressed.

  • The second if checks if it is the left mouse button that is pressed.

  • The else in the second if structure is a good example of 'everything else':

    • • If the left mouse button is pressed make the stroke white (255).

      • Else wraps up any other eventuality, right mouse button, mouse wheel, any other kind of button on the mouse.

More on data types. In sketch 11 you saw that variables are 'of a type'.

int is integer

float is a real number

string is characters

In this example mousePressed is a boolean variable, it is true or false.

mouseButton uses'system variables'. System variables are specific values usually in all caps.

mouseButton can be LEFT, RIGHT or CENTER.