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Inherited methods

We can see from Listing 2 that our new class inherits a method named setup , a method named draw , and a method named size . The code in Listing 2 overrides the setup and draw methods and calls the size method without overriding it.

The class named PApplet defines a huge number of methods. Those methods can be called from within our class named Cars (by novice programmers) without knowledge of anything related to object-oriented programming. They look pretty-much like global function callsfrom the dark ages.

A function library

In effect, the authors of Processing have created a huge function library, (reminiscent of the function libraries of the dark ages of Pascal and C) . Novice programmers can use that library to create sketches using a proceduralprogramming style (as opposed to an object-oriented programming style) ..

A tricycle and a bicycle

While I don't think this is a good way to teach people how to program, I am impressed that the authors of Processing were able to pull it off.

In my opinion, learning to program this way is like trying to learn how to ride a bicycle by riding a tricycle. (I'm not talking about a bicycle with removable training wheels. I'm talking about a vehicle with three fixed wheels.)

As long as that tricycle (the PDE) will get you where you need to go, everything is okay. However, without specialeffort on your part, you will be ill-equipped to put the PDE aside and ride the bicycle (write object-oriented code ) if this is how you learn to program.

Understanding the anatomy of the framework

That having been said, by understanding the anatomy of the framework, it is possible for novices and experienced programmers alike

  • to think in object-oriented terms,
  • to write serious object-oriented programs using the PDE, and
  • to take advantage of the many libraries supported by Processing.

The ability to effectively use multiple libraries is one of the hallmarks of a successful OO programmer.

The draw method

The description of the draw method (that is inherited from the PApplet class) reads partially as follows:

"Called directly after setup() and continuously executes the lines of code contained inside its block until the program is stopped or noLoop() is called.

The draw() function is called automatically and should never be called explicitly.

It should always be controlled with noLoop(), redraw() and loop().

After noLoop() stops the code in draw() from executing, redraw() causes the code inside draw() to execute once and loop() will cause the code inside draw() to execute continuously again.

The number of times draw() executes in each second may be controlled with frameRate() function.

There can only be one draw() function for each sketch and draw() must exist if you want the code to run continuously or to process events such as mousePressed(). Sometimes, you might have an empty call to draw() in your program ..."

Default behavior of the framework

We know that the default behavior of the framework is to display a window on the screen similar to Image 1 if we don't override the draw method.

Questions & Answers

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
how do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
is it a question of log
Commplementary angles
Idrissa Reply
im all ears I need to learn
right! what he said ⤴⤴⤴
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, The processing programming environment. OpenStax CNX. Feb 26, 2013 Download for free at http://cnx.org/content/col11492/1.5
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