In this tutorial I will explain how I used a 3D modelling package (Strata Studio Pro) to create the monster in the image “Lurker’s Roar.” (See ‘Lurker's Roar Image’ at the bottom of the page). This image was inspired by a visit to Whipsnade Wild Safari Park, armed with a 35 mm camera. I took various shots of animals and enclosures with the intention of adding a Jurassic park style monster later.
Stage One.
Starting with the creature’s head, I decided to make the upper and lower parts separately so I could place the jaws in any position I liked. The first thing I did was to create a series of ribs to form a skeleton of the upper part of the monster’s head. I drew the first rib freehand with my mouse. I then duplicated this rib several times and altered the size and shape of the copied ribs to create the skeleton of my monster’s head. I then made the computer skin between the ribs to create a solid shape.(The principle of skinning reminds me of the balsa wood ribs my dad used to create model glider wings. Unlike the glider you can easily unskin your computer skeleton, change the spacing and shape of the ribs until you are happy with the shape that they make.)
Stage Two.
The skinned together ribs formed the top half of the monster’s head. The eye was made by skinning four other ribs together and adding a sphere. The sphere was stretched slightly to give an oval ‘eye-ball’ shape.
Stage Three.
I made the lower jaw by skinning together some smaller ribs. The teeth were made in the same way. Once I’d made one tooth I then simply copied and pasted in as many as I required. I adjusted each tooth slightly by stretching and scaling them to make them look individual. It took about half an hour to make the teeth, tweak them and place them one by one in the creature’s mouth.The tongue was also created by skinning together a series of ribs.
Stage Four.
Once I’d built my components it was time to texture-map them. When people go on about texture-mapping a computer model all they’re really doing is painting it!
It’s amazing how a smooth and plastic-looking model can be made to look realistic by choosing a decent texture. While at Whipsnade Wild Animal Park I took this charming snap of a Rhino’s rear on a 35mm camera. I then took a section of the image and made it into a texture in Photoshop. I could then texture-map the Monster skin image onto my CG beast.
While all computer 3D packages include their own textures I try to create my own. I find the textures that come with the software are usually too ‘cartoony’, so I prefer to take pictures of real textures - leaves, brick, rhinos - which results in a realistic looking model.
To avoid the nasty shiny look that curses many computer images I turned down the reflectivity of the rhino texture down to nothing. I also applied a black and white version of the texture as a ‘bump map’. A bump map makes a smooth computer model look ‘rough and ready.’
Stage Five.
Once I’d made the head then the neck, torso and tail were relatively straightforward. Once again I created some ribs and skinned them together.
I could reposition the neck or tail by un-skinning the bibs, adjusting their position and re-skinning between them. The creature could therefore be put in any position. I could create a herd of monsters just by duplicating the finished model and adjusting each copy separately.
Stage Six.
The next thing to do was texture-map some more of the Rhino texture onto the creature’s torso. All that remained was to knock up some CG legs.
Stage Seven.
The legs consisted of several new ribs skinned together and textured. The claws were created by modififying one of the teeth. Once I’d built one leg it was simple to copy and paste three more and position them accordingly.
Once the beast was built it was time to render the finished model. It is at this stage that I positioned my virtual sun and fill-light to match the lighting conditions of the background photograph. Once I was happy with my lighting I ray-traced the model to produced the finished creature. Ray-tracing means that the computer fires a ray of light at each point on the model. The light beam bounces off each point on the model and returns to the viewer with the relevant information about texture and lighting for that particular point. This process can take many hours, but at least you can go and do something else (like sleep!) while the computer calculates what the finished model will look like.
And Finally...
Once I’d built my ‘Lurker’ it was time to release him into the Wild. I scanned in a photo I’d taken at Whipsnade and used Photoshop to composite the CG model monster into the background. The compositing took a couple of days. Small touches like the Lurker's shadow and reflection in the water helped to ground him in reality. I just feel sorry for the poor deer!
By George Cairns
www.luton.ac.uk/george.cairns/.
