Starting Off

To use raster.js, include the raster library and call some methods on the ra object

const ra = require('raster'); // size of the display ra.setSize(20, 25); // pixels appear 4 times larger ra.setZoom(4); // overlay a grid using 1x1 pixel placement ra.setGrid(1); ra.run();

This code creates a field (the thing that gets drawn to) that is 20 pixels wide with a height of 25 pixels. Setting the zoom to 4 doesn't change the number of pixels in the field, it just makes them appear 4x larger, while still keeping crisp and sharp edges. Next the grid is enabled, showing up at every pixel after the zoom is taken into account. Finally ra.run is what displays the results.

Most methods are flexible in how they can be given arguments. For example instead of calling ra.setSize using positional arguments, as seen above, we can use named parameters by passing a javascript object literal, to provide the width and height:

const ra = require('raster'); ra.setSize({w: 20, h: 25}); ra.setZoom(4); ra.setGrid(1); ra.run();
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