Graphics Reference
In-Depth Information
is a number of ways for graphic display of solid
objects in three dimensions. The simplest solid
objects are called primitives: they are six-faced
cuboids (e.g., a cube), cylinders, prisms, pyramids,
spheres, and cones. Objects can be constructed
from primitives by combining elementary opera-
tions, most often Boolean operations. They include
union (that mergers two objects, for example a
cube and a sphere), difference (subtraction of one
object from another one), and intersection (the
portion that is common to both objects; it means
the set that contains all elements of a cube that
also belong to a sphere).
Other ways are to use parametric curve equa-
tions (mathematical functions defining the sur-
faces). Bezier curves are generated from control
points on a plane. Bezier curves provide convenient
method for interactive design applications.
To develop a 3-D model, one uses several kinds
of commands: first geometric construction com-
mands (such as points, lines, rectangles, circles,
ellipses) in order to design a form, then the manipu-
lation commands (such as rotate, move, mirror,
copy, zoom), and the modifying commands (e.g.,
edit, erase, delete, redraw, scale, etc.). Complex
events with many variables can be shown as 4 or
5 dimensional graphics. Stories of space and time
can be even better displayed by showing variables
in more dimensions, with the use of virtual reality,
or in the immersive environment.
Construction methods build the solids from
simpler shapes. One can sweep a two-dimensional
pattern through some region of space, creating a
volume. Solids with translational or rotational
symmetry can be formed by sweeping a two-
dimensional figure through a region of space (ad-
vanced modeling of complex surfaces). Another
technique uses solid geometry methods to combine
three-dimensional objects with a union operation
which joints two objects to produce a single solid.
Spline is a flexible strip used to produce a smooth
curve through a set of plotted control points, and
spline curves are drawn in this manner.
David Hockney's (2001) topic “Secret
Knowledge: Rediscovering the Lost Techniques
of the Old Masters” reignited the debate on the
use of optical devices for constructing perspec-
tive images in the Renaissance. As an artist,
Hockney brings his insights to the debate. In a
paper “The Implications of David Hockney's
Thesis for 3D Computer Graphics“ Theodor
Wyeld (2011, pp. 409-413) argues that just as
technology informed the Renaissance artist
on ways of seeing and representing natural
phenomena, 3D computer graphics today uses
algorithms to simulate these same phenomena.
For both, various techniques are used to make
the images produced seem real or at least real
enough. In the case of the Renaissance artist,
painterly techniques were used to generate the
illusion of clarity. For 3D computer graphics,
mathematical algorithms are used to simulate
many of the same effects. Striving for real-
ism is a common theme. However, while the
Renaissance artist never lost site of their role
in interpreting what they see, 3D computer
graphics is supposed to be underpinned by the
certainties of its apparent scientific veracity.
The author asks, is this certainty deserved or
is it merely that science and art are intertwined
in ways that mean one is reliant on the other?
Methods of Inquiry: Quantitative
and Qualitative Research Design
Data graphics not only substitute statistical tables,
but also are instruments for visual thinking about
quantitative information. The way of thinking
about the data we need to gather may determine
our research and our inquiry strategies. Generally
speaking, three types of research design are based
on the data under consideration: quantitative re-
search, qualitative research, and mixed methods
research approach.
