Thursday, February 14, 2013

Digital Art, Screenshot, or clueless with the software?

Once upon a time I started with pencil and paper.  My best efforts are in my gallery, but I moved into the digital realm...

First, I have an undo function.

Second, I can save what I do and re-use it at my own discretion (it is, after all, stuff I produced, even a copy of my own material slightly altered).

Humans as primates are tool-users.  What the old and new artists all need to realize is that the computer is a machine, it is a tool.  A paintbrush is a simple machine: a lever.  At its end is a brush, nib, swab, spray, or other device executing material dynamics upon a frictional surface to result in a line, a penstroke, a pencil line...

The computer is another kind of art studio.  It can do whatever you want.  It cannot create art on its own.  The artist must impose a vision.

3D art has become easier thanks to Poser, Daz Studio, and Adobe Photoshop Extended.  The problem is...how do we interpret art?

In truth, there is a great deal of 3D art on DA.  Many people have produced quality images, although with many I have some technical issues...however, they're minor.  But there's also more material that debases 3D art as a medium...mainly because too many people think all you need to do is throw a model together, push a button, and you have instant art without effort.

NOT TRUE.

Daz3D for example, in the Daz Studio 4.5 pro system (geez, you can get this for free) provides the basic Genesis model.  This is a universally morphable model that can produce male and female forms of varying types.  Additional non-human forms require add-ons...this system produces humanoid models.  However, if you buy the Genesis Evolution head and body morphs (yeah, buy...come on, it's like buying a paintbrush set or an easel...or a neverending tube of a particular paint color), you can fine-tune a head to a particular facial structure.  If you dig into the software, learn more of the ins and outs, you can even go beyond that.

Examples:

When I created my fan-art of Tavis Harts for :icontavisharts:, I had to look at a lot of drawn artwork and figure out how to translate it into a three-dimensional life-like model, or a stylized simulacrum.  I'd had some old stuff kicking around and used a GenX emulator to make it work with the Genesis system.  The head is the hardest part, as it carries a great deal of the fine detail that makes a character unique.

When I created my "Awakened Worlds" images, I didn't have the surface maps or shaders (basically, these are render system add-ons that tell the computer to make the image look like something else, working pixel by pixel...you can make something more realistic or more cartoony, whatever you tell the shader to do) I needed...so I rendered as realistically as possible, and worked everything together with Photoshop.

If art was as simple as throwing it together and pushing a button, then Michaelangelo could have just thrown a few globs of clay together carelessly and called it "David."  But part of art is imposing your will on the medium and seeing what happens, even with a few mistakes along the way...sometimes those mistakes can produce inspiration.  (The chocolate chip cookie, for example, originated as an accident...and became a popular treat.)

It's impossible for me to create an editorial that explains the whole of 3D art...I barely know the terminology myself, but I grew up with rendering systems, playing around with computers since I was very young and learning the ins and outs of graphics since high school.  I had to play around with the system, make ludicrous paintings and butcher pictures before I got the hang of it.  Even when people said I had an eye for photography, it didn't make me an expert at creating a picture from scratch.

3D art is part painting and part photography.  You create the environment, but you need to know how to create it.  I can't explain everything, but I can demystify some things.

First, just like in basic physics...you need to find your axes.  The computer should give you a clue as to where up/down, forwards/backwards, and left/right are.  The concepts of X, Y, and Z vary from program to program...but they are consistent.  X is one way, Y is another, and Z is another throughout the software.  Don't strain your brain on this, it's part of getting the feel of the program.

Second...terminology.  It might be a pain, and it might seem like I'm insulting your intelligence, but a few terms can help out a lot.  Some of these terms are quite universal, but sometimes you have to re-orient yourself to a program...once upon a time, I worked with "lathing" in Strata StudioPro.  When I began learning AutoCAD, I couldn't find a "lathe" command, it was hidden as REVOLVE.

Model: A model is a 3D representation of a physical form, anything from a primitive (like a ball or cube) to a complex humanoid form and beyond.  The term can refer to an item in a 3D construct, or to the construct as a whole.

Solid: A 3D model that defines a physical shape.

Primitive: the simplest kind of model represented by simple mathematical geometry.  These can range from 2D models (squares, triangles, circles, ellipses, polygons) to 3d models (pyramids, cubes, spheres, cones, toruses).

Extrusion or sweep: this is what happens when you take a flat shape and extend it along a path.  Extrusions usually refer to shapes extended along a straight line, while sweeps (extrude along path) can follow any line up to the limits of the software.  A square can extrude to a cube or rectangular prism, for example, or a circle can extrude to a cylinder.

Solid of revolution or lathing: If you've ever seen a tradtional-style wooden chair leg, you might notice it's decorative bumps and grooves that run about its circumfrence.  That is because the leg started out as a wooden cylinder that was placed upon a lathe...simply put, a machine which spun the rod about its axis while the machinist applied tools to it.  The rotation against the tool carved it into shape.  In a 3D rendering program, you create a line in the shape of the profile of the item you want...maybe a vase, a table leg, or a piston, and define an axis about which that line rotates to produce that shape.  A simple example...if I take a circle, draw the axis through its center, and tell the computer "revolve it 360 degrees," I get a sphere.  If I take the same circle, place the axis outside of it, and tell the computer the same thing, I get a torus (donut).

Wireframe: This is the network of line segments (edges) and intersections (each one is a vertex, plural vertices) that defines a model.  A wireframe can be manipulated through:
-Edges: these are the individual "wires" making up the wireframe.
-Vertices: the points at which edges converge.
-Faces: Each closed polygon enclosed by edges.

Mesh: Some computer programs split hairs between meshes and solids...they may call a pure solid something that's immutable, but a mesh (in my opinion, a solid with an accessible wireframe) reshapable (3dsmax and AutoCAD do this, but usually they can inter-convert).  Meshes allow you to fine-tune and tweak an object.  Adding edges and vertices allow more fine shaping, but the more stuff there is, the more complex the object.

The model can only be made so detailed before it generates errors in the software or becomes so elaborate that the computer runs out of memory or processing power trying to maintain changes.  Textures not only paint the surface, but they also generate fine details by giving instructions to the graphics processor.  If you've played Halo...ever noticed how Master Chief's MJOLNIR suit is so highly detailed yet he can move so smoothly?  The details aren't in the model (which has to update every frame so he can move), but in the texture mapping.  This makes the details a function of the GPU (painting the stuff on screen) freeing the CPU up for physics and scripts.

Diffuse maps: this is the image itself that is applied over the surface of an object.  It's basically the paint on the skin of your figure.

The following maps, though, are a little trickier to understand.  They are (almost) all in grayscale.  Think of it as a scale represented by black (0%) to white (100%) where each gray shaded pixel represents how much effect is applied.  (Beware: sometimes the software scales black at 100% and white at 0%, so it takes some practice.)

Displacement: This is a fine-tuning factor where more displacement pushes the surface outward further.  The graphics system will render fine three-dimensional details on a surface, treating them as actual physical mini-structures.

Bump: This creates the image of three-dimensionality on a surface...it's great to bring details in while saving render time.

Luminosity: In 2d artwork, it indicates how bright the pixels are (as in, I have a mixture of R, G, and B, but I need a brightness factor to make a color).  In 3d artwork, this is a more potent factor...any luminosity above zero means the region generates light, that is, it becomes a light source.

Specularity: All things reflect light, that's how we see things in the first place.  But...extra light produces "shininess."  Specularity is how the computer knows how shiny something is.  Think of a car...it's been on the road, it has a thin coat of dust, it's matte.  Now have it washed and detailed...the car looks the same, but it has shine in most parts.  The specularity is increased on the paint, greatly increased on the chrome, but still low on functional parts like the windshield wipers.

Gloss: More of a global factor in Daz Studio, gloss tells the computer how much light to reflect physically.  100% gloss is practically a mirror (although the computer is not going to create a mirror unless you have a generic object with 100% gloss in the model).

For dragon scales, the diffuse map is the scale picture...the displacement map is a black and white gradient on each scale (yeah, it's a lot of work, but this will make a more realistic map), with the bump map filling in the details.  The specularity map will tell the computer where each scale is more shiny and where each scale is more dull.




The following examples come from my DeviantArt account here.





These images combine photographed environments and 3D rendered elements in a composite.

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