Scaling in a while loop

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hello, im very new to coding. my college beginner's course uses Java script in Processing 3. for my project, i need to make my avatar scale to a different size every time he goes across the screen. the scaling using a while loop is what im having a problem with. we have to put the avatar in a function call. ill post what code i have below. i need help ASAP! thanks!

Java

int Mart_start_x = -100; //x axis start location
int Mart_start_y = 570; //y axis start location
int Mart_speed = 4; //speed which Mart moves
int r_Leg_x = 50; //'foot' location of right leg
int r_Leg_speed = 1; //speed of which right leg moves
int l_Leg_x = -50; //'foot' location of left leg
int l_Leg_speed = -1; //speed of which left leg moves
int Mart_count = 0; //How many Marts there are
float scale_size = .5; //scaling Mart

void setup()
{ 
   size(1500,750);
}


void draw()  
{
   background (255);
   fill(150);

   MartFunction(Mart_start_x, 570, 1);
    
   //while
   {
      scale_size = scale_size + .5;
   } 
    
   scale_size = 0;
    
   Mart_start_x= Mart_start_x + Mart_speed;

   if(Mart_start_x > width+100)
   {
      Mart_start_x = -100; //This moves Mart across screen
   }

   r_Leg_x = r_Leg_x + r_Leg_speed; //this wiggles right leg START

   if((r_Leg_x > 65) || (r_Leg_x < 35))
   {
      r_Leg_speed = r_Leg_speed * -1; //this wiggles right leg END
   }

   l_Leg_x = l_Leg_x + l_Leg_speed; //this wiggles left leg START

   if((l_Leg_x > -35) || (l_Leg_x < -65))
   {
      l_Leg_speed = l_Leg_speed * -1; //this wiggles left leg END
   }
}

/*************************************************************************/                                          
/*   Function name:  MartFunction                                        */
/*   Description:  Draw Mart when the function is called                 */
/*   Parameters:  int x_loc, int y_loc, float scale_size                 */
/*   Return Value:                                                       */
/*************************************************************************/

void MartFunction(int x_loc, int y_loc, float scale_size)
{
   pushMatrix();

   translate(x_loc,y_loc); //Mart's location

   scale(scale_size);
  
   stroke(5);
   line(0,-50,r_Leg_x,125); //right leg

   stroke(5);
   line(0,-50,l_Leg_x,125); //left leg

   noStroke();
   fill(#084B0F);
   ellipse(0,0,75,175); //body

   noStroke();
   fill(#2C8E11);
   ellipse(0,-100,200,100); //head

   noStroke();
   fill(#EBFF17);
   ellipse(-50,-100,25,50); //left eye

   noStroke();
   fill(#EBFF17);
   ellipse(0,-100,25,65); //middle eye

   noStroke();
   fill(#EBFF17);
   ellipse(50,-100,25,50); //right eye

   popMatrix();
}

What I have tried:

my professor hasn't emailed back since my first email sent over a week ago asking for help. no one else knows what to do

Posted 23-Mar-20 6:07am

DragonNinjaBD

Updated 23-Mar-20 6:51am

phil.o

v5

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Comments

phil.o 23-Mar-20 12:08pm

What is wrong with this code? Please don't say 'it doesn't work', but rather explain precisely in which way it is incorrect.
We are more than happy to help, but we need you to state precisely where you are stuck.

DragonNinjaBD 23-Mar-20 12:18pm

as of right now, it does work. i just dont know how to get the while loop to scale my avatar every time he goes across the screen

DragonNinjaBD 23-Mar-20 12:21pm

i also commented out 'while' so i could test the rest of the code to make sure it works

CPallini 23-Mar-20 12:11pm

It doesn't look Javascript.

DragonNinjaBD 23-Mar-20 12:19pm

thats what my prof told us unless i'm just remembering it wrong

CPallini 23-Mar-20 12:24pm

As far as I know, JS has no static typed variables (e.g. 'int').

DragonNinjaBD 23-Mar-20 12:24pm

ah ok, ill change the tag to just java then, thanks

Richard MacCutchan 23-Mar-20 13:11pm

You are calling MartFunction with a scale_size of 1, so it never changes the sizes. But even if you change the scale_size, it is too late, as you have already drawn the image at 100%.

DragonNinjaBD 23-Mar-20 13:15pm

what should i change it to then?

Richard MacCutchan 23-Mar-20 13:26pm

If you wish to change the size of the image then you need to pass the actual scaling value to MartFunction each time. But it is not clear what you are actually trying to do.

DragonNinjaBD 23-Mar-20 13:33pm

i have him moving from off screen left to off screen right. once he gets off the right side, he resets to off screen left. i want him to change his scale size every time it runs thru, ie, one time he'll be a tiny size, the next time another size, ect

Richard MacCutchan 23-Mar-20 13:36pm

OK, that makes it easy. Whenever you reset the start position to the left of the screen, set the new scale_size. So the image will be the same size as it crosses the screen, but a different size next time it starts. Just try switching between 0.5 and 1.0 to start with so you can test the basic logic.

DragonNinjaBD 23-Mar-20 13:38pm

can i do that using the while loop? cause the loop is a requirement

Richard MacCutchan 23-Mar-20 14:16pm

Yes but that will be outside of the existing code, something like:

Set scale_size to 1.0
set count of number of loops
while (count > 0)
{
    set left position
    while (left position < right position)
    {
        draw image at left position
        add step to left position
    }
    subtract 1 from count
    set scale_size to other value
}

DragonNinjaBD 23-Mar-20 14:20pm

would i need to put it before or after the code for moving him? which is:

Mart_start_x= Mart_start_x + Mart_speed;

if(Mart_start_x > width+100)
{
Mart_start_x = -100;

Richard MacCutchan 24-Mar-20 4:49am

The outer while loop is there to repeat the complete moving of the image some number of times, and changing the scale factor. The inner while loop is where the image moves across the screen. So inside there you should draw the image at each location, using the scale factor set in the main loop.

DragonNinjaBD 24-Mar-20 12:07pm

im sorry im a visual/kinesthetic learner, so unless i see it i have a hard time understanding. thank you for all your help, but sadly i just dont understand ):

Richard MacCutchan 24-Mar-20 12:42pm

Sorry, but I cannot make it much clearer. I would just say that one of the skills you need to develop is the ability to understand pseudo-code, which is what I gave you. Read each line slowly and think about how you relate that to the actual code that you are trying to develop.

DragonNinjaBD 24-Mar-20 13:15pm

thank you so much for your help, it means a lot

DragonNinjaBD 24-Mar-20 12:08pm

like the example code you typed ^ helped, but since i cant see it within the rest of the code its just not clicking for me ):

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phil.o · Answer 1 · 2020-03-23T06:52:00

Solution 1

First, you should not give the same name to a member field and to the parameter of a method (I'm talking about scale_size). You can even get rid of the parameter entirely and use the member field instead.

Second, you are resetting the scale_size value to zero everytime the draw() method is called. Try to comment out this line, and see where it gets you.

As a side question, do you have any debugger with the IDE you are using?

Posted 23-Mar-20 6:52am

phil.o

Comments

DragonNinjaBD 23-Mar-20 13:16pm

what is 'member field'? sorry im very nooby at coding

phil.o 23-Mar-20 13:21pm

A member field is a variable declared inside a class. Here, I am refering to the scale_size variable which you define in the line float scale_size = .5; //scaling Mart.

DragonNinjaBD 23-Mar-20 13:37pm

i got rid of float 'scale_size = .5; //scaling Mart.' but i still need the loop to give him a scale every time he goes thru, and maybe i need to reset it at some point, i dont know

also for your original side question, i have no clue what IDE means.

phil.o 23-Mar-20 14:25pm

I thought of the contrary: keep the member variable, and remove the parameter from the function.
An IDE is an Integrated Development Environment, like Eclipse for java for example.