Requirements For A Visualization Software System For 2010
galathaea
galathaea at gmail.com
Wed Apr 4 21:23:37 CEST 2007
On Apr 3, 12:23 pm, "Xah Lee" <x... at xahlee.org> wrote:
[top posting for clarity]
i have been writing a simulations engine in OCaml
in my spare time over the past few years
it uses openGL as its visualisation engine
it is intended to transform specifications
written in a domain-specific language based on category theory
where the objects are specified by the transformations they
undergo
into "simulations"
i have used the visualisation engine to explore functions
and even posted some of the results
http://tinyurl.com/3262ep
i have also done visualisation in relativistic spacetimes in the past
this included
finite speed of light travel
doppler shift of frequencies / color
and some very basic work in generalised metrics
this was done in POVRay
but i ported most of that over last summer to my own engine
lately i have been working on code generation of the simulations
( to c++ - which i've also posted some about )
so that i can publish my simulations while keeping my core
technology proprietary
but i was going to add more complete construction capabilities of
complexes
basic surgery operations
...
to make its handling of nnoneuclidean geometry more robust
and easier to manipulate through the gui
much of what you posted is either already in my engine
or slated to be added over the next year
so...
if you'd like
i'd love for you to be an evangelist of my technology
and maybe help get my dreams of starting my own company off the
ground
or
if you are looking to develop something similar and become my
competitor
just be warned
i have been studying " the art of war "
;)
( also note that many of your requirements
are already handled by professional programs like maya
and it's MEL scripting interface )
> REQUIREMENTS FOR A VISUALIZATION SOFTWARE SYSTEM FOR 2010
>
> Xah Lee, 2007-03-16
>
> In this essay, i give a list of requirements that i think is necessary
> for a software system for creating scientific visualization for the
> next decade (2007-2017).
>
> (for a HTML version with images, please seehttp://xahlee.org/3d/viz.html)
>
> For the past 10 years, i have been strongly interested in mathematical
> visualization. I'm not a professor, and am not doing it for the
> educational purposes per se. Geometry has just been beautiful for me,
> and i'm also a professional programer. Programing computers to
> visualize geometric theorems or geometric objects, has been a immense
> personal pleasure. A particular aspect of visualization, is to design
> it so that when viewed, it forces a immediate and crystal clear
> understanding of the object or theorem, to its viewers.
>
> I have for the past couple years sought for a software platform/system
> where i can build 3D objects, with abilities to do interactive
> manipulation (such as moving a slider to change a parametric surface's
> parameter), dynamic rotation (viewing from different angles
> instantaneously), animations (such as morphing that shows geometric
> processes), and most of all, walk-thru in it as if it is a building
> (e.g. the perception of actually walking on a moebius strip↗ or Klein
> bottle↗ is vastly different than just viewing it.).
>
> --------
> Requirement: Real-Time 3D Rotation
>
> For math visualization, it is absolutely necessary to be able to
> rotate the object in real-time. For example, when viewing a complex
> surface, a molecule structure, or the design of a complex device. This
> requirement is so basic it warrants no further explanation.
>
> above: The Chen Gackstatter minimal surface as shown by the software
> 3D-XplorMath ↗. This surface has several 3-fold symmetries, but a
> static image does not show this. (Live Rotation with Java Applet)
>
> --------
> Requirement: Real-time Interactivity
>
> The programer should be able to build buttons and sliders that change
> parameters and have the object reflect these changes visually right
> away.
>
> This real-time interactivity is frequently needed. For example, most
> math visualizations involve a function, a process, or a geometric
> object, that varies by parameters, and the key to the visualization is
> showing how the parameter effect the graph or object. Some Examples
> follows.
> Example: Moebius Transformation
>
> above: A software that plots a complex function (the Moebius
> transformation↗), by showing the pre-image and post-image of the
> function. The function is keyed by various parameters that can be
> represented as points in the plane. Dragging these points will change
> the image interactively. Source: MoeApplet by Paul Murray ↗
> Example: Regular Polytopes
>
> above: a Java applet showing a slice of 4-dimensional symmetric
> polytopes↗ , with sliders that change the polytope's parameters.
> Dragging the polytope will rotate it in real-time. Hyperstar Java
> Applet by Mark Newbold ↗.
> Example: Plane Geometry
>
> above: A interactive plane geometry software showing a Equiangular
> Spiral and its inverse curve , with respect to a point O. Equiangular
> spiral is a family of curves varying by a parameter θ, from 0 to π/2.
> This parameter can be changed by dragging the point E of the angle
> DAE, and the corresponding curve will be shown (blue). Its inverse
> curve with respect to the point O is shown in pink. Dragging the point
> O will change the position of O, and corresponding inverse curve will
> be shown in real-time.
>
> above: A plane geometry software demonstrating Bezier curve. User can
> drag the poins to very the input, and see the polynomial change shape
> in real-time. Java Applet version.
> Example: Conic Sections
>
> Computing power today are some 50 times faster than a decade ago.
> However, math visualizations, have hardly advanced. For example, let's
> consider the simple task of plotting of polynomial equations. As we
> know, 2nd degree polynomials of 2 variables are conic sections. It
> would nice, that the program can show the general form A x^2 + B x y +
> C y^2 + D x + E y + F == 0 and let users change the constants by
> sliders, and have the graph change on the fly. Such a application
> would give immense feedback that reinforces learning, which is what
> visualization is about. Similiarly, this can be done for 3rd degree
> polynomials, and the visualization of polynomials of 3 variables.
>
> There are tens, if not hundreds, elementary equation and function
> graphing software. However, it is almost impossible to find one that
> shows the power of interactivity described above. Apple Computer Inc,
> bundled with OS X as current as of March 2007, a plotting software
> (called Grapher↗) that has zero interactivity features. And
> Mathematica's abilities for plotting polynomial equations in as late
> as 2005, is basically the same as 1996. Its ability for visual
> experiment and learning of polynomials of 3 variables is practically
> zero.
>
> I have personally played with perhaps over 20 major plotting software
> over the past 15 years, and i only know one that has this feature.
> (see Nucalc↗)
>
> --------
> Requirement: easy-to-create, real-time animation
>
> The software system must have the capabilities for programers to build
> animations, and view the animation interactively in real-time (as
> opposed to generating the animation once and save it as a movie).
>
> For example, once a programer has coded the animation, she should
> easily play it forward and backward in the program, as well as
> changing parameters and re-run the new animation without going thru
> some compilation or export process. For example, if the animation
> involves a 3D object, the system should also allow the user to rotate
> it while the animation is on-going, all in real-time.
>
> For example, this system should allow programer to easily create a
> animation that morphs a sphere into a cube, or a bunch of spheres
> flying in space as a swarm of flies or in some artificial formation
> like a 3D-kaleidoscope.
> Example: Cycloidal Curves
>
> above: A movie generated by a math software, showing how the cycloid
> curve is generated by rolling a circle. (cycloidGen.mov).
>
> In this example, you can see the trace by a point on the boundary of
> the circle. What happens if the tracing point is nearer to the center
> of the circle? This is a example where a interactive slider will help.
> As a user adjust the slider, the animation should show its effects in
> real-time.
> Example: Cellular Automaton
>
> above: A software that computes the cellular automaton↗known as Game
> Of Life, showing it as a animation as it evolves. At any point in
> time, a user can add more cells to it by clicking in the window, and
> continue the animation to see its effects.
> Example: Helicoid-catenoid Surface Family
>
> above: A frame of a software generated animation, showing the isometry
> property of the surface family helicoid-catenoid. (helicoid-
> catenoid.mov)
>
> This is a example where it shows the importance of being able to
> rotate the object in real-time in a on-going animation.
> Example: Sphere-eversion
>
> above: The classic Sphere-eversion visualization problem, visually
> demonstrating how a sphere can be turned inside-out without creating
> any crease. (Source: John Sullivan et al. ↗. image source ↗, accessed
> on 2007-03-18.) (For detail about this problem, see: Smale's paradox↗)
>
> Examples of system that do NOT satisfy this requirement would be:
> Mathematica (up to version 5), 3D-XplorMath, most CAD systems. Most of
> these systems allow animations, but usually for a generate-once and
> save-as-static-movie-file, not designed for interactive view.
> Example: Stereographic Projection
>
> above: A illustration showing stereographic projection. (source)
>
> To create visualization for stereographic projection, ideally, the
> user should be able to rotate the whole plane, or move it up and down
> in relation to the sphere, as to see the effect on the mapping. Also,
> the user should be able to rotate the sphere and see the mapping
> change on the plane. The user should also be able to move a single
> projection line to see mappings of arbitrary points. Lastly, it is
> ideal in this visualization to let users change the pattern on plane
> or on the sphere to arbitrary images. For example, the plane should
> have a default set containing rectangular grids and polar grids.
> (showing the important property of circles mapping to circles/lines)
> The sphere should have standard projection of platonic solids.
> (showing the important concept of platonic solids as networks) And,
> the user should be able to put the graph of arbitrary complex function
> on the plane or a Riemann sphere↗ on the sphere.
>
> Today, it is non-trivial to create a visualization such as this. For
> example, the above image is created in Mathematica. One has to write a
> function that plots riemann sphere in the first place, to create the
> image of the sphere. The system also needs to have animation and
> interactive slider abilities, as to be able to make the sphere and
> plane rotate or reposition independently in real-time, and the moving
> of the projection line.
>
> Examples of visualization systems that do satisfy the animation
> requirement to various degrees discussed in this section would be:
> Macromedia Flash, VPython, 3D Game Engines.
>
> --------
> Requirement: Walk-thru
>
> The software system should have the capability of walk-thru or fly-
> thru. That is, allow the programer precise control of the camera
> position and orientation in real-time.
>
> The most obvious application of this requirement is in CAD systems
> that are specialized for architecture.
>
> For example, if i build a fancy 3D-maze or elaborate cathedral, i
> should be able to say, walk inside it, so as to view the object from
> inside and as well as getting the real experience of perceiving such a
> building.
>
> The ability to do walk-thrus has significant applications in math
> visualization too, however, it is seldom realized. Here are some
> examples of its application.
> Example: Walking on Surfaces
>
> above: A hyperbolic-paraboloid, with a human character standing on top
> of it. (from the computer graphics virtual world Second Life. Credit:
> Henry Segerman↗, aka Seifert Surface.)
>
> Compare the above image with the following abstract rendering that is
> commonly found in math visualization software.
>
> above: a abstract rendering of the hyperbolic-paraboloid. Java Applet
>
> Perhaps due to the evolution of our perception system, the experience
> of actually walking on or inside a math object, is vastly different
> than just seeing it as zero-thickness abstract lines and sheets
> rotating around its center.
>
> Although, the virtual world created by computer graphics only fake the
> experience of actually being there, still, such a virtual world
> experience throws a impact on understanding. Imagine, demonstrating
> the one-sidedness property of surfaces such as the moebius strip↗ or
> Klein bottle↗ thru a live rotation and explanation, compared to having
> the student inadvertently taking a walk inside such a object and
> suddenly felt the single-sided oddity. A person experiencing such a
> situation will probably remember it as part of his life's memory.
> Example: 3D-Lattices
>
> The ability to do walk-thrus also fits well in visualizations
> involving 3-dimensional lattices, such as Crystallographic group↗, 3D-
> tilings (sphere packing), or visualizing periodic minimal surfaces.
>
> For example, the following images of periodic minimal surfaces are
> shown in the way they are traditionally presented, as a few
> representative patchs of the periodic surface, and users can rotate
> the surfaces in real-time:
>
> above: Periodic minimal surfaces↗. Source: Richard Palais, Karcher
> Hermann. ↗)
>
> As they are shown, their periodic structure is not visually clear,
> especially those non-rectangular ones. (e.g. the last 3) It also takes
> some effort to imagine how they actually fill the space.
>
> Now, imagine these shown in a walk-thru system, where a portion of
> space is filled with its repetitions, and the user effectively becomes
> a bee, flying about in it, able to observe detail in a close-up on any
> point of the surface from any angle, or getting a bird's eye's
> overview of the surface's lattice symmetry.
> Example: 3-Manifolds
>
> above: Screenshot of Jeff Week's Curved Space ↗ software. This program
> lets users fly-thru various 3-manifolds↗ . There is basically no other
> way of visualizing 3-manifolds other than the techniques of walk-thru.
>
> There is effectively no visualization system that lets programers
> easily code interactive walk-thrus. The possible exception is 3D Game
> Engines↗, however, it requires a specialized programer with years of
> dedicated experience to create any thing in it, and the work is rather
> tedious. Some such game engines have higher level (scripting)
> languages that let the user (players) create objects or scenes in-
> world. (A example is the Linden Scripting Language↗ of Second Life↗. )
>
> --------
> Requirement: Easy To Use For Average Programers
>
> The system must be easy to use for average programers or scientists.
> For example, a person who had just a year of programing experience,
> should be able to code a variety of visualization projects with the
> system.
>
> Often, these high-level languages are called scripting languages.
> Mathematica↗, Lisps (Logo↗, Scheme↗, Tcl/tk↗ ), Visual Basic↗,
> VPython↗, Macromedia Flash↗, CAD systems (AutoLISP↗ ), Linden
> Scripting Language↗ are examples of high-level systems.
>
> On the other hand, low-level language such as Java↗, C sharp↗, or,
> systems such as OpenGL↗ and Game Engines↗, or application programing
> systems such as Cocoa (API)↗ and X Window System↗, all require
> professional programers with years of experience to create a non-
> trivial application. These are not useful to most scientists or
> engineers.
>
> --------
> Requirement: A Set of Basic Geometric Shapes
>
> The system must have a set of basic primitives or shapes that serve as
> building blocks. For example, spheres, torus, cubes, as well as meshes
> of triangles.
>
> Of course, the system should also have the following common elements:
> various coordinates systems, projection systems, lighting and camera
> control, build-in manifold by parametric surfaces and algebraic
> equations, and a whole set of 2D and 3D transformation functions
> (which can also work on n-dimensional coordinates).
>
> For a system aimed for math visualization, it would also be necessary
> to have access to a full range of math functions, such as integration,
> derivative, higher-order functions.
>
> [Continues on page 2]
>
> -----
> This post is archived at
>
> I'm still working on the second part. Your opinions and comments on
> existing systems are welcome. Thanks.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
galathaea: prankster, fablist, magician, liar
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