Ambient Light

    Ambient Light is light that doesn't seem to come from a specific source, but is just there. Look under the desk - it's pretty dark, but there's some light there. In the real world, this is caused by stray photons bouncing around and occasionally ricocheting under the desk. Ambient light is basic, minimal amount of light in the whole scene. Adding too much ambient light makes a scene look washed out. Since the light doesn't come from anywhere, all sides of an object are illuminated equally, and it won't have any shading on it.

Ambient Occlusion

    Ambient Occlusion (AO) is a ratio of how much ambient light a surface point would be likely to receive. It simulates a huge dome light surrounding the entire scene. If a surface point is under a foot or table, it will end up much darker than the top of someone's head or the tabletop.

Armature

    Armature is the interconnection of bones that form the skeleton of an animated figure. The Inverse Kinematics library contains the code to make armatures move. The armature must still be rigged with 3D objects to give shape to its head, hands, trunk, feet, etc.

BF

    BF is Blender Foundation

Blend

    Blend refers to the verd to Blend, working with Blender; also Blender's file extension.

Bounce Light

    Bounce Light: Simple lighting situations have a single light, called a key light, illuminating one side of an object. This creates strong shading and definition of the volume of the object. However, a 3D light will often make the contrast too great - the dark side of the object is completely black since no light is hitting it. In reality it would still be lit a little, just not as much as the brightly lit side, because of light bouncing around the room and hitting the dark side of the object. In realtime 3D, bounce light is not calculated, so you have to create it yourself. Either add a little ambient color, or put a second, less bright directional light pointing the opposite direction to give a little light to the shadows.

Depth of Field

    Depth of Field (DOF) is the distance in front of and behind the subject which appears to be in focus. For any given lens setting, there is only one distance at which a subject is precisely in focus, but focus falls off gradually on either side of that distance, so there is a region in which the blurring is tolerable. This region is greater behind the point of focus than it is in front, as the angle of the light rays change more rapidly; they approach being parallel with increasing distance.

Diffuse Light

    Diffuse Light is even, directed light coming off a surface. For most things, the diffuse light is the main lighting we see. Diffuse light comes from a specific direction or location, and creates shading. Surfaces facing towards the light source will be brighter, while surfaces facing away from the light source will be darker.

Directional Light

    Directional Light is a light that has a specific direction, but no location. It seems to come from an infinitely far away source, like the sun. Surfaces facing the light are illuminated more than surfaces facing away, but their location doesn't matter. A Directional Light illuminates all objects in the scene, no matter where they are.

Environment Maps

    Environment Maps (EnvMaps) is the method of calculating reflections (such as in the Video Commentary). Involved rendering images at strategic positions and applying them as textures to the mirror.

Focal Length

    Focal Length of a lens is the distance along the optical axis from the lens to the focus (or focal point). The inverse of a lens' focal length is called its power.

Focus

    Focus of a lens is the point onto which collimated light parallel to the axis is focused.

GE

    GE is Game Engine.

Index of Refraction

    Index of Refraction (IOF) is about the way that light passes through different types of materials... diamond, glass, water etc. When a light ray travels through the same volume it follows a straight path. However if it passes from one transparent volume to another, it bends. This is why a straw in water looks bent. The amount of bending differs between materials. The angle by which the ray is bent can be determined by knowing two things: the angle at which the incoming ray has been cast and the Index of Refraction. This IOR value is unique for every material. Glass has an IOR of about 1.5 and water 1.3. By increasing the IOR value for a Blender material, you can control how much the environment behind the transparent object is distorted, and thus improving the realism of the shader.

JPEG

    JPEG: Acronym for Joint Photographic Expert Group (pronounced jay-peg) is a commonly used standard method of lossy compression for photographic images. The file format which employs this compression is commonly also called JPEG; the most common file extensions for this format are .jpeg, .jfif, .jpg, .JPG, or .JPE although .jpg is the most common on all platforms.

Luminosity

    Luminosity (more properly called luminance) is the density of luminous intensity in a given direction. In astronomy, luminosity is the amount of energy a body radiates per unit time. It is typically expressed in the SI units watts, in the cgs units ergs per second, or in terms of solar luminosities, Ls; that is, how many times more energy the object radiates than the Sun, whose luminosity is 3.827×1026 W.

Motion Blur

    Motion Blur is the simulation of the phenomenon that occurs when we perceive a rapidly moving object. The object appears to be blurred because of our persistence of vision. Doing motion blur makes computer animation appear more realistic. It can be thought of as adding back some of the time dependence expressed in the Rendering Equation.

Normal

    Normal (Surface Normal) to a flat surface is a three-dimensional vector which is perpendicular to that surface. A normal to a non-flat surface at a point p on the surface is a vector which is perpendicular to the tangent plane to that surface at p.

Normal Mapping

    Normal Mapping is similar to Bump Mapping, but instead of the image being a greyscale heightmap, the colours define in which direction the normal should be shifted, the 3 colour channels being mapped to the 3 directions X, Y and Z. This allows more detail and control over the effect.

Open Project

Open Project refers to some end result that will be published under an open license, free for everyone to re-distribute, re-use or publish.

Orange

    Orange is the first Blender open movie project.

Refraction

    Refraction in geometric optics is the change in direction of a wave due to a change in velocity. It happens when waves travel from a medium with a given refractive index to a medium with another. At the boundary between the media the wave changes direction; its wavelength increases or decreases but frequency remains constant. For example, a light ray will refract as it enters and leaves glass.

Rig

    Rig: the controls that aid in the manipulation of a digital character.

Rigging

    Rigging is the process by which a person creates constraints and relationships between objects that will generate controls to aid in the manipulation of a digital character.

Scanline

    Scanline is one row of pixels in the final render. Also the term for one of the methods of rendering which Blender can use. It is much faster than Raytracing, but allows fewer effects, such as reflections, refractions, motion blur and focal blur.

Shadows

    Shadows: simulated lights don't normally cast shadows. And, they also pass through solid objects - so a light inside a closed box would actually illuminate things outside the box as if the box were transparent. The shading on objects is only calculated based on the angle of the surface.

Spotlight

    Spotlight is a light with both location and direction. A spotlight sends out a cone of light defined by the spotlight angle, and illuminates only objects within that cone. Spotlights also have attenuation, as well as a parameter that controls whether the spot of light is sharply defined or has smooth edges. These 4 types of lights are listed in order of computational complexity; the more lights you have, the more work the computer has to do. Generally it's a good idea to use directional lights whenever possible, since they're the cheapest, and use pointlights and spotlights sparingly.

Tuhopuu

    Tuhopuu is an experimental version of Blender that is like a code playground, developers can put their new code in there to be tested and played with by users before it gets put into the official Blender. Tuhopuu is Finnish for "Tree of destruction".

Tweening

    Tweening is short for in-betweening, the process of generating intermediate frames between two images to give the appearance that the first image evolves smoothly into the second image. Tweening is a key process in all types of animation, including computer animation. Sophisticated animation software enables one to identify specific objects in an image and define how they should move and change during the tweening process.

UV Mapping

    UV Mapping (UV) This refers to the process of re-parameterizing a 3d object with dimensions x, y and z into a 2d plane with coordinates u and v. Most texturing requires this step because it tells the program HOW to apply a 2d image map onto a 3d object. If all your textures must be 2d and flat, the easiest way to determine what pixel goes where is if your model is flattened and made 2d. It also establishes a relationship between a 2d image and the mesh such that if the mesh deforms, the image map will deform along with it. Think of it as skinning a cat and pinning its hide onto cardboard to facilitate painting it!

WC

    WC is Weekend Challenge.

WIP

    WIP is Work In Progress