photo credit: flashbackz
Those old BW Walt Disney cartoons when they first appeared seemed three-dimensional compared to the stick figure Felix the Cat animations people were first used to looking at before. Until Fantasia appeared in the 1940’s, those breathtaking color images seemed pretty much three-dimensional as compared to what was seen before. So this is the overall trend. The more real-world details a drawing is endowed with, the more your brain is willing to feel that it is being shown the real thing – until it grows used to it. The more CPU power available rises today, the more real-world details an animator is able to bring in. So it is the details that brain sub coconsciously picks up upon.
Ok, you’ve seen people out there on the web that make these really great 3d wallpapers for your computer desktop: the scenery and things in it have a perfect molten metal look that looks – well — perfect. These pictures look real and 3d but at the same time a little unreal for 3d. Now, they don’t truly jump out of the screen, jarring the viewer, like in those old movies that required a pair of special red and blue color tinted glasses; these two dimensional representations of 3d drawings, the kind computers make these days, are so amazing for a different reason: they are precisely shaped, with realistic lighting, reflection, perspective and texture that convince the eye. For these qualities they seem at first glance as convincible and as real and three-dimensional as a real photograph, but they are of course created mathematically. So how is this effect achieved exactly?
A simple geometrical object such as a soccer ball is a great way to understand how a computer algorithm makes 3d drawings. If you have ever seen one, they make those balls sewing together the 32 individual five- and six-sided polygons (pentagons and hexagons) of leather into a perfect sphere. So this is the trick, a series of flat surfaces create the illusion of curves. The element of this surface is a polygon and is a basic unit of the computer graphics program in any computer. When you want a shape, any kind, the computer figures out how to draw one out of an arrangement of an assortment of triangles and polygons, just the way a soccer ball is made out of 32 polygonal panels. Once a wireframe that is filled with polygons is in place, the program needs to figure out a number of other things: what kind of surface the skeleton is to have, hard and shiny or soft and dull; the surface needs to be reflecting light a certain way, and its color is to shine or dull out depending on where the light is shining from.
Beginners who are learning computer graphics often like to take a challenge where they paint in a 3d drawing into a real photograph, say, a computer-drawn hat on the head of a man in a photograph, only to pass their handiwork around and ask people to find out if the hat is real or artificial. You would be surprised how many people get it wrong. The object doesn’t match up in texture and lighting with the person in the photograph
A real object doesn’t really need to think about how each visible quality turns out: it just is the way it is. And the way it is just happens to be incredibly varied and complex. The shape itself has such a fine texture of infinite depth; it reflects and absorbs light in a hundred ways. Even a simple rock is not a uniform material all over. This then, is one of the best ways to make a 3-D drawing look real: to patiently give it as many different textures all over, and make them reflect light in different realistic ways.
Tags: photo realistic