What does the 'sqrt' equation mean?

Processing Beginners
1

What does the sqrt equation mean?

2

Hi and welcome

This might explain how to us it

3

From the same link above

int cols, rows;
int scl =15;
int w = 2000;
int h = 1600;

float flying = 0;

float[][] terrain;
import peasy.PeasyCam;

PeasyCam cam;
void setup() {
  size(800, 800, P3D);
  cam = new PeasyCam(this, 400);
  cols = w / scl;
  rows = h/ scl;
  terrain = new float[cols][rows];
}


void draw() {

  flying -= 0.1;

  float yoff = flying;
  for (int y = 0; y < rows; y++) {
    float xoff = 0;
    for (int x = 0; x < cols; x++) {
 if (2222 - ((x- 53) * (x - 53) + (y- 53) * (y - 53)) > 0) {
   terrain[x][y] = sqrt(2222 - ((x- 53) * (x - 53) + (y- 53) * (y - 53)))*12;
   
      
      
} 
     // terrain[x][y] = map(noise(xoff, yoff), 0, 1, -100, 100);
      xoff += 0.2;
    }
    yoff += 0.2;
  }



  background(0,222,1);
 // stroke(2,5,255);
 stroke(5);
 strokeWeight(7);
  noFill();
scale(.2);
  translate(width/2, height/2+50);
  rotateX(PI/3);
  translate(-w/2, -h/2);
  for (int y = 0; y < rows-1; y++) {
    beginShape(TRIANGLE_STRIP);
    for (int x = 0; x < cols; x++) {
      vertex(x*scl, y*scl, terrain[x][y]);
      vertex(x*scl, (y+1)*scl, terrain[x][y+1]);
      //rect(x*scl, y*scl, scl, scl);
    }
    endShape();
  }
}

Eidt this code based on @jb4x help thanks for him

4

Hi @blopplop,

sqrt() is a function that take the square root of a number. You will often find it to compute the distance between 2 points: it comes from the pythagoras theorem.

Go have a look at this link to get more insight: Distance Between 2 Points

1 Like
5

also want to mention that there is a special processing dist() command for the distance between two points:

so:

float distMy = dist (rectX, rectY, quadX, quadY);

Also PVector (see reference Reference / Processing.org) has a dist() function.

1 Like
6

quote=“blopplop, post:1, topic:32875, full:true”]
What does the sqrt equation mean?
[/quote]

The sqrt() function:
https://processing.org/reference/sqrt_.html

It is used by the dist() function:
https://processing.org/reference/dist_.html
The sqrt() function is used “behind the scenes” in the source code for Processing.

Advanced below… but good to know. It may come in handy one day.

If you take a look at source code for Processing you will find both the sqrt() and dist() functions here in PApplet.java

Direct link (takes a moment to open and go to line) to dist() function in PApplet.java:

Note:
You edited your original question and this changes the context of your question.

:)