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Dreamy Kid
11-03-2006, 05:52 PM
Hi everyone, i've been learning about shadow in perspective recently < outdoor and indoor light>, and been doing some practices determining shadow and the length of it using simple objects such as box and cone. However i'm a bit confused and have some questions to ask, and hopefully get some help.

i have no problem determining shadow when the object is simple, but when the object is complicated ( such as stacked boxes and vase ), i have difficulties deciding the shadow points and how it falls on the surface. if anyone can give me a picture or example, i'd really appreciate it

and lastly, in case of the outdoor light source / sun, how can i know for sure the length of the shadow.

here are some ref pictures from perspective made easy by R Norling, it's a good book that covers everything about perspective but it's too bad that he did not cover a lot regarding the shadow in perspective. your help will be much appreciated, thank you :)


sorry for the low quality picture, i just took a quick snapshot using my crappy webcam

light from a nearby source

http://img102.imageshack.us/img102/8764/1si2.gif




light from outdoor source / the sun
http://img104.imageshack.us/img104/4825/2ak1.gif

http://img243.imageshack.us/img243/734/3ry0.gif

T-Scholes
11-23-2006, 11:06 PM
Hey I have that book! .. it's an ok primer I guess... hehe.

http://www.handprint.com/HP/WCL/perspect6.html
More than you ever wanted to know about shadows in perspective, good luck trying to understand it all ... hehe.

gl0gg
11-23-2006, 11:30 PM
Hey!

You decide the shadow of boxes stacked on each other and more complicated objects by projecting the corners down to the ground and go from there. It just means that instead of having to keep track of two projections at a time (a box on the ground) you will have to keep track of three instead: 1. projection of corner on the ground. 2. lower corner on object 3. higher corner on object. If you're doing a shadow on a box on the ground then you only have to know the lower and upper corner. Follow me? (I suck at explaining, if you don't get it I'll try and draw something).

The other question, how you know the length of the shadows cast by the sun is pretty easy, instead of projecting the line from the light source straight down on the ground (which you would do if it was for example a candle light in a room), you project a line to the horizon and figure out your shadows from there.

Does this make any sense whatsoever? It's all so clear when I think about it, but turns to s**t when I type it out :sad:

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11-23-2006, 11:30 PM
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