interactive-shader-format-for-modv/tests/renderer-test.js

Rendering engine for Interactive Shader Format effects and generators

var test = require('tape')
var fs = require('fs')
var getPixels = require("get-pixels")
var savePixels = require("save-pixels")
var gl = require('gl')
var ndarray = require('ndarray')
var imageDiff = require('image-diff')
var ISFRenderer = require('../src/ISFRenderer')

if (!fs.existsSync('tmp')) fs.mkdirSync('tmp')

function assetLoad(name) {
	return fs.readFileSync('./tests/assets/' + name).toString()
}
var width = 128, height = 128
const destination = {width: width, height: height, offsetWidth: width, offsetHeight: height}
function matchFilterToExpected(src, expected, callbacks) {
	var ctx = gl(128, 128)
	var renderer = new ISFRenderer(ctx)
	renderer.loadSource(src)

	if (callbacks.steps) {
		callbacks.steps(renderer)
	} else {
		renderer.draw(destination)
	}

	var pixels = new Uint8Array(width * height * 4)
	ctx.readPixels(0, 0, width, height, ctx.RGBA, ctx.UNSIGNED_BYTE, pixels)
	var nd = ndarray(pixels, [width, height, 4])
	var filename = "./tmp/" + Math.random() + ".png"
	var writableStream = fs.createWriteStream(filename)
	savePixels(nd, "png").pipe(writableStream)
	var expectedFilename = expected.split('/')[expected.split('/').length - 1]
	imageDiff({
		actualImage: filename,
		expectedImage: expected,
		diffImage: './tmp/diff.' + expectedFilename
	}, function(err, areSame) {
		if (err) throw err
		callbacks.finished(areSame)
	})
}

test('Basic Generator Rendering', function(t) {
	var generatorSrc = assetLoad('generator.fs')
	var callbacks = {
		finished: (same) => {
			t.equals(same, true)
			t.end()
		}
	}
	matchFilterToExpected(generatorSrc, "./tests/expected/generator.png", callbacks)
})


test('Persistent Buffers', function(t) {
	var generatorSrc = assetLoad('persistent-buffers.fs')
	var callbacks = {
		steps: (renderer) => {
			renderer.setValue("xPos", 0)
			renderer.draw(destination)
			renderer.setValue("xPos", 0.5)
			renderer.draw(destination)
			renderer.setValue("xPos", 1.0)
			renderer.draw(destination)
			renderer.draw(destination)
		},

		finished: (same) => {
			t.equals(same, true)
			t.end()
		}
	}
	matchFilterToExpected(generatorSrc, "./tests/expected/persistent-buffers.png", callbacks)
})