# Help with some patterns

**URL:** <https://forum.electromage.com/t/help-with-some-patterns/854>\
**Category:** Patterns and Code\
**Created:** [December 26, 2020, 8:17pm UTC](https://forum.electromage.com/t/help-with-some-patterns/854 "2020-12-26T20:17:11Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![wizard](https://forum.electromage.com/user_avatar/forum.electromage.com/wizard/32/4_2.png) [@wizard](https://forum.electromage.com/u/wizard)\
**Post date:** [December 26, 2020, 9:11pm UTC](https://forum.electromage.com/t/help-with-some-patterns/854/2 "2020-12-26T21:11:53Z")

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Hi @nickbeaulieu,  
That looks pretty sweet! To get the most out of it, you’ll want a 2D pixel map. Then you can use a bunch of the 2D patterns and get some sweet effects.

Check out this post for a simple click mapper:

> [@2D Pixel coordinate mapping tool for images](https://forum.electromage.com/t/pixel-coordinate-mapping-tool-for-images/714):
>
> Here is a quick and dirty pixel mapping tool. You can upload a photo, click to mark a coordinate on the image, press z (not control-z) to remove the last coordinate. It puts the coordinates into a text area for copying to pixelblaze mapper tab, drawing the pixel index number on the image. Remember, Pixelblaze mapper coordinates can be in any unit, pixels work too slight_smile The coordinates are in pixels from the source image. It will also accept edits/pastes into the text area to edit …

Once you have a pixel map, you can get things like radius and angle (and some patterns do this already) and use that instead of index/pixelCount to upgrade many patterns.

There’s a pattern on [the pattern sharing site](https://electromage.com/patterns/) with some utility functions for getting angle/radius (assuming centered in a piece) called “angle and radius from coordinates”

Here’s a post with some more background and examples of how these might be used:

> [@How does mapping fit in the PB real-time architecture?](https://forum.electromage.com/t/how-does-mapping-fit-in-the-pb-real-time-architecture/782/6):
>
> Hi @DrOldies, You mention the thread, but I wanted to be sure to point out this framework for arranging arbitrary matrixes with various offsets and rotations: Yes, the pixel map is rendered in your browser using real JavaScript, and a 2D or 3D normalized map of the pixel coordinates is stored. While you can live code that part too in order to get the mapping right, the ideas is as @Scruffynerf mentions, the map itself is usually static once set. The mapper text should resolve to either a jso…

Once you get a 2D pixel map installed, I would humbly suggest you try out my clock pattern 🙂

> [@RGB Clock 2D Pattern](https://forum.electromage.com/t/rgb-clock-2d-pattern/818):
>
> I’ve just uploaded a customizable clock for 2D setups to the [pattern site](https://electromage.com/patterns/). I’m putting the code here too, since it relates to several recent discussions and some of the components may be useful to folks making their own clocks. /\* Draw a clock in 2D using RGB. The second hand is drawn in red, minutes are green, and hours are blue. Sub-seconds can be displayed as white. There are several controls that can adjust the way the clock is drawn. The clock face drawing is broken up into 2 mode gro…

As an example of upgrading a pattern I took millipede and have it use angle. you can see the 1D render and render2D side by side to see how it was modified:

```auto
speed = 20
legs = 10

export function beforeRender(delta) {
  t1 = time(1 / speed)
  t2 = time(2 / speed)
}

export function render(index) {
  h = index / pixelCount 
  h += (index / pixelCount + t2) * legs / 2 % .5
  v = wave(h + t2)
  v = v * v // Gamma correction
  hsv(h, 1, v)
}

export function render2D(index, x, y) {
  //use angle around a center point instead of distance on a strip
  h = (1 + atan2(x - .5, y - .5)/PI2) * .5 
  h += (h + t2) * legs / 2 % .5
  v = wave(h + t2)
  v = v * v // Gamma correction
  hsv(h, 1, v)
}

```

I’ve also uploaded a fancier version with controls to the sharing site.

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