Computer Graphics - Circle and Midpoint Circle Algorithms

A set of vocabulary flashcards based on the lecture notes covering computer graphics focusing on circle properties, algorithms, and drawing techniques.

Cartesian Coordinates

A system where points are represented by pairs of numerical coordinates (x, y).

Circle Equation

The equation representing a circle with center (xc, yc) and radius r is given by r = (x - xc)² + (y - yc)².

Radius (r)

The distance from the center to any point on the circle.

Quadrant Symmetry

A circle exhibits quadrant symmetry if it is divided into four equal parts by its horizontal and vertical diameters.

Octant Symmetry

Further division of a circle into eight sections, where each section is called an octant.

Midpoint Circle Algorithm

An algorithm used to draw a circle by generating points using the properties of its octants.

Decision Parameter (P0)

A parameter used in the Midpoint Circle Algorithm to determine the next point on the circle's boundary.

Trigonometric Calculations

Mathematical computations involving angles, which are used in polar coordinates for circle drawings.

Octant

One of the eight equal sections into which a circle can be divided based on its symmetry properties.

Plotting Points

Using calculated coordinates to render points on the graphical interface or screen.

Floating Point Arithmetic

Mathematical computations involving float numbers, which can be time-consuming.

Circle Center Coordinates

The specific point (xc, yc) that represents the center of the circle.

Shifting Points

The process of adjusting computed coordinates from the origin to another center point (xc, yc).

Initial Conditions

The starting values assigned in the Midpoint Circle Algorithm to initiate the circle drawing process.

Iteration

The repetition of steps in the Midpoint Circle Algorithm until the required points are generated.

Symmetry Property

The characteristic that allows the generation of symmetrical points across the circle’s quadrants or octants.

Radius Calculation

The process of determining the radius used in circle drawing algorithms.

Point Generation Steps

Important steps in the Midpoint Circle Algorithm for generating points: initialization, decision parameter calculation, and point plotting.

Decision Parameter Update

The adjustment of the decision parameter after plotting each point to decide the next point's position.

Point (X0, Y0)

The coordinates representing the center of the circle in the coordinate system.

Algorithm Completion

The conclusion of the Midpoint Circle Algorithm after plotting all necessary points.

Mirror Effect in Drawing

The technique of generating points for the second octant by using symmetrical principles from the first octant.

Eight-Symmetry Property

The feature of circles allowing the calculation of points in all octants using only the first octant's calculations.

Point (xk, yk)

The current point being evaluated in the Midpoint Circle Algorithm.

Draw Command

The instructions used to render a point on the screen based on calculated coordinates.

Termination Condition

The stopping criteria for the looping process in the algorithm when the desired points are generated.

Visualization of Circle Points

The graphical representation of the calculated points that form the shape of a circle.