Isometric Math Helpers
This is a small JS library designed to help out with isometric math. By design it is simply the isometric math functions required to translate from x,y,z isometric space to the x,y screen coordinates (and associated functions).
What you do with it is up to you.
The first step in using isomath is initializing an isometric projection.
This is done by calling the
isomath function. If called without any
parameters then it defaults to the 1:2 project.
var isomath = require'isomath';// get a reference to a projection (optional, but encouraged)var projection = isomath;// project the isometric coordinates 0, 10, 50console.logprojectionproject0 10 50;// --> [ -44.721359549995796, -32.3606797749979 ]
As you can see above, the project function returns an array of x, y coordinates. Why an array? Let me show you:
var projection = require'isomath';var crel = require'crel';var canvas = crel'canvas' width: 500 height: 500 ;var context = canvasgetContext'2d';// set the origin to the centre of the canvasprojectionorigin250 250;// draw a simple linecontextmoveToapplycontext projectionproject0 0 0;contextlineToapplycontext projectionproject200 0 0;contextstroke;documentbodyappendChildcanvas;
Wonderful, isn't it :)
You will see in many guides on using canvas, that it's a good idea to clamp your values to aid performance. In general having values aligned around the 0.5 value will produce a well performing and visually appealing display.
Should you want to clamp values (I do), then specify clamp true when initializing your projection.
NOTE: When doing this you will always have to manually specify the isometric projection ratio (default = 0.5):
var isomath = require'isomath';// get a reference to a projection, specify clampingvar projection = isomath0.5 clamp: true ;// project the isometric coordinates 0, 10, 50console.logprojectionproject0 10 50;// --> [ -45, -32 ]
Create a new isomath projection using the specified
ratio and applying
any options that have been provided.
Get or set the current projection origin.
This function is used to project from the x, y, z coordinates from isometric space to 2d screen coordinates.
Based on routines outlined at: http://www.kirupa.com/developer/actionscript/isometric_transforms.htm
Copyright (c) 2013 Damon Oehlman firstname.lastname@example.org
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