Printing Text to screen problem

Programming Questions

mrbunzy

Printing Text to screen problem

in Programming Questions • 1 year ago

Hi All,
I wonder if anyone has come across this and found away round it. I'm in the beginning stages of a new project. AS part of this project I need to print strings to the screen via the text() function. My problem is that I need to print the strings to screen as the code runs. However I've noticed that in Processing the loop has to complete once before printing the String to the screen via text(); is there a way around this? To demonstrate what I mean I've put a simple script below.

PFont font;
int counter = 0;

void setup()
{
size(500, 200);
smooth();
}

void draw()
{
background(255, 0, 0);
println("I am at the top of the loop");
delay(2000);
font = loadFont("Arial-Black-24.vlw");
textFont(font);
String s = "test Text";
println("I have been around the loop " + counter);
text(s, width/2, height/2);
delay(2000);
counter++;
}

Replies(6)

calsign

Re: Printing Text to screen problem

1 year ago

Firstly, some remarks that will probably change the code structure that led to your problem:

Don't load anything in draw()... it's designed to run 60 times a second! Load your font in setup().
Don't use delay()! It is misconceived as being usable for this purpose time and time again, but that is not what it is meant for. Instead, spread your drawing out across multiple frames.
You have a variable called counter... there's another variable built-in to the framework called frameCount designed for this purpose.

To fix this problem (as mentioned), you have to split the display up across multiple frames.

gspot38

Re: Printing Text to screen problem

1 year ago

Actually it prints..

It shows a red background with the text "test Text"..

If you wait for a long, it will print what you want..

The font you are using takes TOO MUCH time to load..

I tried it with verdana and it loads almost immediately!

calsign

Re: Re: Printing Text to screen problem

1 year ago

The problem isn't the font (although loading it in draw() is a problem), but, rather, it is the fact that delay() is being used instead of multiple frames... as explained above...

gspot38

Re: Printing Text to screen problem

1 year ago

Sorry, we posted at the same time..

tfguy44

Re: Printing Text to screen problem

1 year ago

PFont font;
int counter = 0;
int timeForText = 4000;
void setup()
{
size(500, 200);
smooth();
font = createFont("Arial", 24);
textFont(font);
}
void draw()
{
background(255, 0, 0);
text( "Wait for the boom...", 20, 44);
if( timeForText <= millis() ){
text("BOOM!", width/2, height/2);
}
}

Don't load things in draw().
Don't use delay(). It doesn't do what you think it does.
The function draw() runs 60 times a second. If you want something to be drawn only after certain conditions have been met (such as the program having been running for a certain period of time), then you'll need to have conditional statements in draw that control what is and is not drawn in each frame.
frameCount is a variable that keeps track of the current frame number.
millis() is a function that tells you how long (in milliseconds) your program has been running.

mrbunzy

Re: Re: Printing Text to screen problem

1 year ago

Hi all,

Thanks for your quick responses, they're most helpful. I'm aware of frameRate, though have never employed frameCount. I'll inviestigate this further. I am aware of delay and I know what it does: it stops the code running for a specified time. Sorry if my code was unclear. I've delay in there so I can read the console window to see how processing executes screen events after it has read the associated code. It seems it reads once through the whole loop and goes back to the start before doing anything. I wasn't aware that it read through the loop once before executing. Sounds like a stupid thing to miss.

The above isn't from the project I'm working on. I wrote it quickly to frame a problem. Now I know processing reads through the loop once before executing I need to have a little think about if this will impact my project.

Thanks for your help, I really appreciate it. Sorry if my question was a little dumb sometimes it's the most obvious things that are easily overlooked.

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