test rendering

[jeromeetienne]

• see if the rendering is what you expect

[jeromeetienne]

• no lib is currently doing it
• could be use by three.js too
• what about a post on learningthreejs

[jeromeetienne]

• currently this is using mocha to make normal js test
• what are the step to code this ?
  • do the images comparison
  • do the image download/upload
  • find a nice api for the test in mocha

[jeromeetienne]

Possible Algo

• there is a reference image
  • a human looks at it and check it is valid
• the code does its test and output an image
  • if the test output is the same as as the reference image (here how to test they are the same ?)
  • then the test succeed, else it failed
• if there are no reference image, store the current image as reference image
  • the process of the human checking the reference images is done separatly

[jeromeetienne]

how to save the test image as reference image

• possible solutions
• upload to a normal server. something in node.js should be easy to code
  • to require a server makes it harder to run
  • the server needs to be launched, the test needs to know which ip:port
  • depends on node.js, require it to be installed etc...
• filesystem api seems to be able to make it
  • to test. i dunno this api
  • it seems supported only by chrome (from version 13+)
  • how to test on firefox then ?
  • http://www.html5rocks.com/en/tutorials/file/filesystem/ tutorial on it
• the no firefox + inability to check the file outsire... no good
  • so forced to do the upload via server
  • see with python. it may be even easier

[jeromeetienne]

how to compare if 2 images are similar

• mae, psnr etc...
  • http://bigwww.epfl.ch/sage/soft/snr/ list of the formula
  • http://en.wikipedia.org/wiki/Mean_absolute_error
  • math seems impressive but it is real simple
  • issue of Number overflow ?
• pixastic to do it
  • no such plugin exist
  • what about submittng a plugin (asked on twitter)

[jeromeetienne]

This image processing stuff is an optimisation, not a requirment