3D Terms
Vertex - is, simply said, point in 3D world. Its position is determined by 3 axis(x,y,z). Points are connected with other polygons with edges. Minimaly 3 points with 3 edges can create single polygon. One vertex (point) can be "connected" with n edges. Point doesn't have volumic value, meaning that if there is single point or 2 points connected with one edge, they won't be rendered with render software. Acctualy they will be, but they are very thin so you won't see them. Edges are connections of two vertexes. They are also one of n sides of polygons and they determin final look of polygon with render software in render window or rendered picture.
Polygon - is flat surface made from minimaly 3 points and 3 edges. Usualy that number is 4, but it is unlimited. Every polygon has two faces. Front and back face. Faces are important for light reflection. Face determination is done with vertex normals. If camera is looking at back face of polygon. Rendered from that camera, polygon will be almost black, acctualy we won't get wanted results. If we are rendering with camera looking front face we will get wanted results(textures, etc..)
Vertex normals - are short imaginary lines that show orientation of point. If we have 4 point polygon and 2 points are oriented to one way we would have see well rendered half of polygon in render view.
Object is set of different connected polygons, vertexes, edges that they create recognizable object to a user. Object can be set of connected components mentioned abouve or can be group of few object or meshes. Object are also used for easier manipulating of position of vertexes.
Meshes are similiar to objects but they're not just any group of vertexes, polygons.. They are uniqe group of them. Some meshes are also called objects. Thats what I call, term confusion. Lets take example of 2 cases. If we have group of automobile parts, each one positioned at its place, than every one of them is a mesh because it isn't group of more meshes. If we group these meshes we would get object. If we make uniqe object from these meshes we would get mesh object of a car. Unlike object meshes are uniqe group of only polygons (vertex, edges, not curves or rounded surfaces)
On this picture:
- Polygon is red color
- Edges are yellow color
- Points(Vertexes) are blue
- Normals are blue lines with begining at points
- Two boxes are objects(or meshes) If we apply Unite Boolean operation on those two we would get mesh object.
NURBS are Non-Uniformal Rational B-Splines) way of defining curves and surfaces with CVs (Control Vertexes) and vectors-tangents. NURBS objects and surfaces dont have polygons, so they have ideal rounting.
Selected objects are B-Spline, NURBS curves, and
between them is NURBS object created by lofting
Loft is process when creating object, surface object from two NURBS curves.
Boolean operations are consisted of 3 operations. Those operations from two object make one. One of operations is uniting, which does uniting 2 objects into new one. Second operations creates new object which is intercepting area of those two objects. 3rd one does cutting first object with second one and creates new object.
Alpha channel -> most of pictures have 3 channels (Red, Green and Blue) but with alpha channel we can show transparency, which is very useful in compositing. Picture that presents alpha channel is black&white.
Antialising - is softing of alised edges that are showed in rendered picture by mixing neighbouring pixels. Most of programs have this ability but there are some programs specialized for that job.
Bounding box - it is 3D object of box with 6 polygons, but it is acctualy presentation of some more complex 3D object. You see a box, in 3D scene but in render, other object will be rendered. These are used when creating complex scenes if your computer can't support scene because of hardware weakness.
Bump was developed in 1978, and it is texture applied on object which gives user, that surface on which bump is applied, is not flat surface, but it has bumping where bump map is white colored. Bump map is black-white picture (NOTE!: not black&white version of texture). Some programs have ability to generate bump map.
Clipping -> This is procedure that does reducing amount of data which are calculate for rendering because for datas out of camera range calculation is not done.
Culling -> Ability that for hidden materials and objects that are in camera range but behind some other object, calculation is not done.
Morphing -> Changing shape of object during animation (shape animation)
OpenGL -> SGI developed GAPI (Graphic Application Programming Interface), that is multiplatform (MacOS, SolarisOS, LinuxOSes, WindowsOS, IRIX). It is advanced version of IRIX GL. It is used in big number of games, and in every more popular 3D program.
Particle -> ojects that are used for simulating rain, steam, water (aldo lately are used special fluid simulators), custom particles, snow, etc...
Refraction -> Inverse of reflection.
Viewport -> window with look to 3D scene (or just scene for compositing programs, video programs, etc..), where you can do translation, scaling, rotating, etc... of polygons, vertexes, edges, objects, meshes, etc....
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