Merge pull request #23 from guanlun/master

reflection bug fixed
Merge pull request #24 from guanlun/master

added glossy reflection
Merge pull request #25 from guanlun/master

multithreading implemented
Merge pull request #26 from guanlun/master

added some interactivity...
Merge pull request #27 from guanlun/master

rendering starts from the middle
Merge pull request #28 from guanlun/master

more interactive
Merge pull request #29 from guanlun/master

glossy refraction implemented
Merge pull request #30 from guanlun/master

better mouse control
Merge pull request #33 from guanlun/master

glossy uses normal distribution
Merge pull request #34 from guanlun/master

added support for normal mapping
still not working
Merge pull request #35 from guanlun/master

added shadow attenuation
Merge branch 'master' of https://github.com/hkust-psan1/FYP
Merge pull request #36 from guanlun/master

quick fix for pixel out of range
bug fix for atten
merge
export script supports area light