Thursday, 14 May 2009

Creating Crowd Scene in CGI

Over on the downthetubes forum, Ex Astris creator Mike Nicoll has been talking about creating crowd scenes in CGI, responding to comments from veteran artist John Ridgway that the medium isn't really good for such things.

Mike's response was pretty interesting, so I thought I'd re-post them in an edited form here.

"The problem with CGI work is the characters," argues John Ridgway. "In order to produce the necessary pictures, characters have to be created, posed, lit and their expressions arranged to suit the story. All this takes time. Mike Nicoll, on Ex Astris, manages this exceptionally well. But the number of characters in their scenes are limited. Imagine producing a number of crowd scenes...

"My solution to this is to draw the characters and use cgi for the backgrounds and spacecraft," says John. "It's then up to the individual reader and being given the time for this mixture to be accepted. No-one objected to the use of flat coloured line drawings against fully-painted backgrounds in the old Disney films, and apparently didn't even notice that the ballroom in Disney's Beauty and the Beast was CGI work."

Mike thinks John Makes a good point about crowd scenes although so far as Ex Astris is concerned the reason for a lack of major crowd scenes is simply down to the fact that the script(s) as written haven't actually called for any - yet.

"We did create a one-pager called Ex Astris: Floods [which was adapted for mobile for ROK Comics] which had a crowd storming an escaping space ship," he points out, "and the EA: Homecoming 10 pager we did for Bulletproof Comics had between four and seven characters in many panels and the main storyline which we're working on at present will have a mob of townspeople attacking our heroes which will be fun to do (memo to John Freeman - let's have lots of close-ups!).

"The problem may be simply that much CGI work is, as pointed out elsewhere, created by technicians who may be adept at computer skills but not in the art of comic creation," Mike argues. "That's not to denegrate the creators, it's simply that as someone who is as happy hand-drawing a page as CGI-ing it I have an extra batch of creative skills which many CGI artists lack.

"When I create a CGI scene there is frankly as much Photoshop and hand-rendered post-production work as there is pure CGI rendering. I almost never render a complete scene and pop it into place (if only it were that easy!!). Instead, I sketch the image first then render each element separately via the alpha channel, then compose the panel with every item on a separate layer.

"It may seem like a lot of extra work but it gives me maximum control over lighting, colour balance, contrast etc., but the point I'm trying rather laboriously to make is that it's just as easy for me to make a scene with two people as 22 people in CGI. All it costs you is a little extra time but if I were to hand-draw the crowd then I'm taking extra time as well but in the long run I'm saving time by not having to ink and colour the panels.

"That said, I feel the ideal way to go about solving the problem is, as John says, to hand-draw the characters but use CGI backgrounds in the same way as actors are shot against greenscreen in the movies. However, as shown to great effect in the movie Titan AE, this can result in a bit of a mess because the line art and flat colour jars terribly against the rendered backgrounds.

"My solution is to hand-paint the characters with no line-art involved - at least no black line-art which I feel is the main problem. Fully painted characters against CGI backgrounds (which also have no line art of course) blend in better and make a much more satifsying composite I feel.

"I'll be using this technique on a Dan Dare wallpaper which I'm doing for fun and if it gives satifactory results I'll be using it for my forthcoming Saffyre Blue graphic novel so I'll pop up some sample art a bit later for some constructive criticism."

Read the whole discussion on the downthetubes forum