# Processing Month, Day 2 - Connecting Points, Part 2

Posted by Jan Vantomme on 02 May 2011.
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Today’s sketch will be similar to the one from yesterday, only we’ll use random points and connect them in a different way. We will draw a line if the distance between the points is less than a certain number. The distance will also be used as the value for the transparency of the line. Points close to each other will have a less transparent connection between them, points that are further away will be connected by a very transparent line.

To calculate the distance between points, we’ll use the `dist()` function. First two parameters are for the x and y coordinates for the first point, the third and fourth parameter take the x and y coordinates for the second point. The method returns the distance between the two points as a float. If this value is less than 255, we will draw the line.

``` float dst = dist( points[i].x, points[i].y, points[j].x, points[j].y );if ( dst < 255 ) {    stroke( 255, 255 - dst );    line( points[i].x, points[i].y, points[j].x, points[j].y );}  ```

Once we have drawn the fine lines between the points, we need to draw the points themselves, with a bigger stroke weight. This will make our final image look a lot better. So this code will be added at the end the first for-loop, right after the inner loop.

``` stroke( 255 );strokeWeight(4);point( points[i].x, points[i].y );  ```

### Documentation

Here are some links to the Processing documentation for the functions I used. The might be handy if you need some extra information.

Sketch for Processing Month, Day 2

From: Dan Bernier
Date: 04.05.2011

Very nice - it's a good 3D effect in 2D. One trick I like to use for static sketches like this is to put all the work in draw(), add noLoop() at the bottom of draw(), and add a mouseClick handler: void mouseClicked() { loop(); } This way, you can just click to re-run the sketch. BTW, for anyone who missed the earlier post, you can see this sketch in action at http://www.openprocessing.org/visuals/?visualID=28023.

From: Jan Vantomme
Date: 04.05.2011

Thanks for the tip to regenerate static sketches. Might be useful for other readers.

From: Simon
Date: 05.05.2011

This is excellent, thanks for sharing it.

From: Ian Bowman
Date: 05.05.2011

I really like these Processing Month sketches. They are informative, yet concise. I've expanded upon your Sketch 2 idea by adding animation and an image generation component: http://ibowman.loni.ucla.edu/2011/05/04/processing-month-day-2-—-remix/