current cell (maze generator)

Lv99Abra

trying to recreate daniel's maze generator from his p5 video into processing. stuck at the part where he creates "var current" and sets an object to current. i cant figure out what variable to make current. btw using 2d array for grid.

[mod edit, copied video link from comment]

GoToLoop

https://GitHub.com/processing/p5.js/wiki/Processing-transition
https://developer.Mozilla.org/en-US/docs/Web/JavaScript

Lv99Abra

apparently it was posted in p5.js, swapped it to "how to..." dunno how it got to "p5.js" using processing. watching the video where he uses p5. just confused on what variable he makes "current" in the video. >.<

GoToLoop

Oops! It's about p5 not p5.js. Sorry! b-(
So the most correct section would be "Library Questions" then. Since it's about the video library.

Lv99Abra

yes i guess so, just dl'd processing not to long ago and still learning about it. and havent programmed in a while so this is my coming back to programming lol. hopefully someone can help me figure it out =D

GoToLoop

You can raise the chances by posting the link for the video and your own attempt about it.

GoToLoop

BtW, https://www.Reddit.com/r/processing/new/ is also a nice place to get help. O:-)

Lv99Abra

during first like.... 2 minutes

https://youtube.com/watch?v=D8UgRyRnvXU&list=PLRqwX-V7Uu6ZiZxtDDRCi6uhfTH4FilpH&index=11

//global initated variables
int w = 40;
int cols, rows;
Cell [][] grid;

void setup() {
  //draws the window
  size(400, 400);

  //sets number of columns = to width divided by object width
  cols = width/w;

  //sets number of rows = to height divided by object width
  rows = height/w;

  //sets a grid array to columns and rows (I.E. (5,3) would be column 5 row 3
  grid = new Cell[cols][rows];

  //creates the cells inside of the grid
  for (int j = 0; j < rows; j++) {
    for (int i = 0; i < cols; i++) {
      grid[i][j] = new Cell(i, j);
    }
  }

}

void draw() {
  //sets background color
  background(0);

  //displays the grid
  for (int i=0; i<grid.length; i++) {
    for (int j=0; j<grid.length; j++) {
      grid[i][j].display();
    }
  }
}

class Cell {
  //Cell Class variables
  int x, y;
  boolean walls[] = {true, true, true, true};

  //creates temporary variables when Cell is called to create grid
  Cell(int i, int j) {
    x = i*w;
    y = j*w;
  }

  void display() {
    //trbl = top right bottom left

    //creates walls for top side of cells
    noFill();
    stroke(255);
    if (walls[0]) {
      line(x, y, x+w, y);
    }

    //creates walls for right side of cells
    if (walls[1]) {
      line(x+w, y, x+w, y+w);
    }

    //creates walls for botttom side of cells
    if (walls[2]) {
      line(x+w, y+w, x, y+w);
    }

    //creates walls for left side of cells
    if (walls[3]) {
      line(x, y+w, x, y);
    }
  }
}

GoToLoop

That video is indeed using p5.js library, not Processing Java! 8-|

Lv99Abra

yes i know, im trying to make it in java lol. i got stuck at when he makes the variable "current" idk what type of variable to make it. thats the problem lol

GoToLoop

I don't see any variable called current from the code you've posted.
In Java, all variables have to be declared w/ the datatype it's meant to store.

Lv99Abra

in 1:50 to 2 minutes he declares "var current;"

after that he makes it current.visited = true;

i just cant figure out what variable datatype current is suppose to be

(current being the current cell)

GoToLoop

If you can't figure out the datatype of variable visited, how come you've hit the bull's eye about variable walls'? boolean walls[] = {true, true, true, true}; :>

GoToLoop

Just a second... you mean variable current, which doesn't show up in your code here? Maybe it's of datatype Cell? :-/ Gotta watch that video in order to make sure then... :(|)

Lv99Abra

yeah, current is in his video, im trying to figure out what variable type to declare it lol. sorry. its almost 4 am and ive been drinking, so not the best way to word things on forums lol...

GoToLoop

@ 1:55 he states: "So this variable current is the current Cell."
Therefore current is of datatype Cell: Cell current;. :-B

Lv99Abra

yeah that works. but when i try to make it into a boolean its all like no. lol. like he does "current.visited = true;" and im trying to get that to work. blah maybe i need to sleep on it lol

GoToLoop

Since variable current is of datatype Cell, it can only access members from that class.
I can't spot any variable called visited inside your Cell definition btW. 8-X

Lv99Abra

yeah ive tried putting boolean visited inside of the cell class, but it just says "global variable 'visited' does not exist" when i do current.visited = true;

i think i have to do an if statement or something. idk i appreciate the help though!

Lv99Abra

ok so progress, i got it to kind of work, but i need current to equal the current cell. i did "current = grid" just to get something working but how would i make it just the specific cell?

GoToLoop

You should keeping reposting your current sketch. It's hard to guess what's your current situation otherwise.

Lv99Abra

yeah sorry, been busy lol. so i got it to work kind of. i know the problem is "current = grid;" but ive tried multiple combinations that i can think of and none of them select just the first cell. i havent messed with arrays in a while, and this is my first project in... 4 years? lol. so little bit rusty

//global initated variables
int w = 40;
int cols, rows;
Cell [][] grid;

Cell current[][];

void setup() {
  //draws the window
  size(400, 400);

  //sets number of columns = to width divided by object width
  cols = width/w;

  //sets number of rows = to height divided by object width
  rows = height/w;

  //sets a grid array to columns and rows (I.E. (5,3) would be column 5 row 3
  grid = new Cell[cols][rows];

  //creates the cells inside of the grid
  for (int j = 0; j < rows; j++) {
    for (int i = 0; i < cols; i++) {
      grid[i][j] = new Cell(i, j);
    }
  }




  current = grid;








}

void draw() {
  //sets background color
  background(0);



  //displays the grid
  for (int i=0; i<grid.length; i++) {
    for (int j=0; j<grid.length; j++) {
      grid[i][j].display();
    }
  }

}

class Cell {
  //Cell Class variables
  int x, y;
  boolean walls[] = {true, true, true, true};
  boolean visited = false;


  //creates temporary variables when Cell is called to create grid
  Cell(int i, int j) {
    x = i*w;
    y = j*w;
  }

  void display() {
    //trbl = top right bottom left

    //creates walls for top side of cells
    noFill();
    stroke(255);
    if (walls[0]) {
      line(x, y, x+w, y);
    }

    //creates walls for right side of cells
    if (walls[1]) {
      line(x+w, y, x+w, y+w);
    }

    //creates walls for botttom side of cells
    if (walls[2]) {
      line(x+w, y+w, x, y+w);
    }

    //creates walls for left side of cells
    if (walls[3]) {
      line(x, y+w, x, y);
    }

    //colors current cell
    if(current == grid) {
    fill(255,0,255,100);
    rect(x,y, w,w);
  }
  }
}

Lv99Abra

to make it clear ( just incase of confusion) trying to make "current" the current cell, which should start at top left cell.

GoToLoop

• As stated, variable current points to the current active Cell.
• And all of Cell objects are stored in your grid[][] 2D array.
• But variable current is meant to point to just 1 Cell, not all of them!
• Therefore variable current should be declared as datatype Cell, not Cell[][]. :-B

GoToLoop

And given you're using a 2D array, it's advisable to read about it: O:-)
https://Processing.org/tutorials/2darray/

Lv99Abra

i had looked at it the other night, but i had a few to drink so half the time just skipping things lol. thank you though. i think i got it ( it selected the cell) but mind if i keep this open for a sec just in case?

Lv99Abra

eh i think that got it. i can always post again if i get stuck. thank you. (btw i realized at the bottom i had

if(current == grid) {
   fill(255,0,255,100);
   rect(x,y, w,w);
}

and it should have been

if(visited) {
   fill(255,0,255,100);
   rect(x,y, w,w);
}

so it was always going to make it purple. but what you told me helped a lot. hopefully i can move on! thank you