Graphics Definitions Flashcards
Affine Combination
A transformation that keeps parallel lines parallel but does not keep angles the same.
Affine space
A basis in n-dimensions by which affine transformations can be defined.
Aliasing
Sampling high frequencies at low frequencies causing errors. In images this happens when more detail occurs than can be sampled by a pixel. Can mitigate with anti-aliasing.
Alpha Blending
When you have materials with transparency (alpha) and pixel colour is determined by mixing materials based on alpha.
Ambient reflection
A way to approximate global illumination by adding light regardless of whether shadow rays touch the point.
Anti-aliasing
Removing aliasing by improving sampling rates or other methods
B-spline
Parameterized curve using second-order derivatives
Backfacing polygons
[?] Faces whose normals point away from the view direction. i.e. the dot product of the normal and the view vector is positive.
Barrel distortion
Warping of the image due to glass in the lens of a physical camera.
Barycentric coordinates
[?] Coordinates within a square used to calculate linear interpolation
Baud rate
The speed at which a beam in a crt monitor covers the screen
Beam settling delay
Something about the laser in a crt
Beam penetration crt
[?]
Bézier
[?] A curve parameterized in a special way
bitblt
Not sure
Bresenham
The line for calculating which cells/voxels in a grid a line intersects with. Used for: spatial subdivision acceleration, occupancy grid mapping.
BRM
[?]
Bump Mapping
Perturbing normals when calculating lighting at a point in order to give the appearance of noisy textures
Button
a user-interface item
Callback routine
A routine that gets executed after the completion of another routine.
Calligraphic display
[?]
Cap Polygon
[?]
Cathode
Cathode Ray Tube is a style of early monitor where a laser painted the picture onto a phosphorous coated screen.
Chromaticity diagram
[?] Shows how colour can be constructed with three variables on a two-dimensional graph.
CIE
[?]
Collector
[?]
Collimator
[?]
Color Map
A range of colours that can be returned depending on a variable.
Compensation table
[?]
Concave object
A line can be drawn between any two points in the object and it will not intersect the object anywhere inside.
Convex combination
[?]
Convex object
There exists a line through the object where it intersects with the object at more than just at the two ends of the line.
Crossbar Switch
NO
Cross Product
Only for two vectors in 3D space. For A, B, angle theta, and normal N:
A x B = ||A|| ||B|| cos( θ ) N
DAC
[?]
DDA
[?]
Decay
[?]
Deflection Coil
[?]
Delta Gun
[?]
Diffuse reflection
A term in the local lighting model approximation. Diffuse is the random lighting (i.e. is not influenced by the angle of the light hitting the surface)
Distributed Ray Tracing
Kijaya’s paper. A way of generating an image by approximating lighting with rays sent from the view (rather than from the lights) in parallel and recursively.
Dithering
[?] The approximation of how light decreases in intensity over distance
DMA
[?]
DMA
[?]
Doping
Lance Armstrong
Dot Product
Sum of element-wise products of two vectors. Also geometrically, the angle between two vectors.
A . B = sum_i ( a_i * b_i )
A . B = ||A|| ||B|| cos θ
Draggin
[?]
DVST
[?]
ECL
[?]
Electromagnetic
Electricity and magnetism
Form Factor
[?] A relationship between a surface patch
Related: Radiosity
Fragment Shader
OpenGL shader that colours between vertices by interpolating materials from vertex colours.
Frame
One image in an animation
Frame Buffer
[?]
Gamma Correction
A way of causing changes in light intensities to appear more realistic to human eye.
I_ij = I_ij * (v_j / v_max) ^ Gamma
GKS
?
Gouraud Shading
A way of interprelating shading from vertices and their normals, but not phong shading…
Gravity Field
Related: Physics
Hertz
Rate of sampling
Homogenous coordinates
?
Opponent colours
A theory of colour where blue/yellow, red/green, and black/white are opposing colours detected by rods in our eyes and every colour must be along those bands.
Phong Shading
Interpolating normals between verticles of surrounding normals to create smoother shading along edges.
Phosphor
Chemical. Used to coat early displays because it would light up when hit by a laser (CRT)
Related: Phosphorescence, CRT
Phosphorescence
The chemical reaction leading to light emitted from phosphor
Related: CRT
Pixel
Picture element. Represents a single colour in an image.
Plasma Panel
A type of display that …
Radiosity
Method for approximating lighting. Divide surfaces into patches and calculate the light hitting each patch and the bounces of light from all other patches. Add up light. Very computationally intense when models get detailed/surfaces are not flat.
RGB
Red, Green, Blue
Shader
An OpenGL construct for representing light and material interactions
Specular Reflection
Changes with angle of the light
