Canvas library

# Canvas library

OpenSCAD library to project canvas with random images on 3D shapes

# Howto

We must first convert the image to grayscale data using [img2gray](https://github.com/JustinSDK/img2gray) designed from this thing: https://www.thingiverse.com/thing:3830079. This is the reason why i declare this thing as a remix.

The test image comes from [clipart-library](http://clipart-library.com/clipart/709738.htm):




Then:
```
$ python img2gray.py penguin.jpg penguin.scad
```

The generated file contains the function `levels_penguin();` which gives image data.

Sample OpenSCAD file to project the image on a plane:
```
use
use
use

empty = newCanvas( [2,1], [200,100] );
penguin = levels_penguin();
canvas = drawImage ( penguin, empty );
flat = canvas2mesh( canvas );

meshPolyhedron ( flat );

```

Or projection on a cylinder:
```
...
flat = canvas2mesh( canvas );

// Insert th