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Programming Languages


Computer Training Excuses - No ExcuseYou wouldn't go to a doctor who had never been to medical school, or hire a lawyer who never studied law. One side-effect of a world advancing as rapidly as ours is that fields are becoming more and more specialized and narrow. People can no longer get by on general knowledge in their careers, something I found out for myself not too long ago. I'd been out of high school for two years, scraping by on my own and picking up scraps of programming as I went. I saw all of the self-taught programmers breaking into the IT industry, and I hoped to do the same. After all, IT is one of the few industries out there where being creative and a quick learner is more important than a degree.
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Which is the Easiest Programming Language? - Programming LanguagesIf you have some misconception in mind that the programming languages are easy or hard, I am afraid to say that you are mistaken. To tell you frankly about the programming languages, there is nothing such as easy or tough programming language. The only thing that you need to keep in mind while stepping into the world of programming languages is that which programming language would set your base by giving you in-depth knowledge of programming logics and the basics of programming techniques.
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Entering into Programming World - Good Luck ProgrammingOnce you have learned some programming languages, you feel yourself completely prepared to enter into the programming world, and start working on the programming languages that you have learned. Many students also feel that they have learned extra things which might be helpful in their programming careers. The matter of fact is that the real world is entirely different from what you have been taught in the classrooms.
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Why Programmers Love the Night - Programming at night One famous saying says that programmers are machines that turn caffeine from coffee and Coca Cola into a programming code. And if you ask a programmer when does he like working the most and when is he most productive - he is probably going to say late at night or early in the morning, that is when he has the greatest energy and concentration to work.
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How to be a Programmer - Programing training To be a good programmer is difficult and noble. The hardest part of making real a collective vision of a software project is dealing with one's coworkers and customers. Writing computer programs is important and takes great intelligence and skill. But it is really child's play compared to everything else that a good programmer must do to make a software system that succeeds for both the customer and myriad colleagues for whom she is partially responsible. In this essay I attempt to summarize as concisely as possible those things that I wish someone had explained to me when I was twenty-one.
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VRML Tutorial - VRML TutorialThis VRML tutorial will give the newcomers a head start with VRML. Starting with the history and basics, this tutorial will guide you to a point where with a little effort, even new comers will be able to create a decent VRML structure all on their own. Not only is this a recommended tutorial on VRML but (in our best hypothesis) with a good understanding of VRMl, it is easier to learn more advanced concepts of general programming. It is highly recommended that all who are interested in advancing in VRML at-least skim through this particular tutorial.
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TW Tech Glossary - Misplaced your bible? Well here it is - Tech Glosasary! This truly took a while to complete and should be used by all from beginners to advance techies.
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How to Install the Aptana Studio IDE on Windows - Aptana Studio 3IDE (Integrated Development Environment) represents an integrated development environment in which you can develop applications. This tutorial will be useful to all those that considering doing programing...
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What Programming Language To Learn - Programming LanguagesOne of the most common questions we hear from individuals hoping to enter the IT industry is, "What programming languages do I need to know?" Obviously this is a complex question, and the answer will depend on what field the questioner is going into. Many programming languages are taught during courses used to obtain a computer information science degree. However, those already in IT know that the greatest skill you can have is to be a jack-of-all-trades. A well-prepared worker can switch between computer programming jobs with only minimal training, thanks to a wide knowledge of multiple programming languages.
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What is VRML?

VRML stands for Virtual Reality Modeling Language. VRML is a specification for displaying 3-dimensional objects on the World Wide Web. We can think of it as the 3-D equivalent of HTML. Files written in VRML have a ".wrl" extension (short for world). To view these files, one need a VRML browser or a VRML plug-in to a Web browser.

VRML produces a hyperspace , a 3-dimensional space that appears on your display screen. And you can figuratively move within this space. That is, as you press keys to turn left, right, up or down, or go forwards or backwards, the images on your screen will change to give the impression that you are moving through a real space.


Tips

Navigation

Most VRML browsers support multiple modes of navigation. One method is POINT (or LOOK), which allows users to click on objects that they wish to navigate to. However, this disables linkable objects. Other modes include FLY, SPIN, SLIDE, etc.

Perhaps the easiest way for novices to navigate VRML is to use WALK mode. Unlike other modes that may leave the user wandering hopelessly upside-down, or jetting off into space, WALK always keeps your viewpoint upright, looking parallel to the horizon.

To navigate in WALK mode, click and drag your pointer (mouse, trackball, pen, etc) in the VRML display area -- being careful not to click on an object unless you wish to link to a new URL. Dragging upwards will generally move your viewpoint forward; dragging downwards will move you back. Dragging left or right, will swing your viewpoint left and right.

Get lost in WALK mode:

If you get lost in WALK mode - keep turning left... eventually you'll turn to face the main part of the model.

Colors

Use colors whenever possible. Only use textures when absolutely necessary, they slow down traveling in your world.

Small Worlds

Keep your worlds small, as its harder for the user to navigate with the world still downloading.

Inlining of objects

Inline the objects that you are animating, or that are not part of the scene.

LOD nodes

Use LOD nodes if your world is large in size, and you want the user to navigate the world even when its downloading.

Differences between VRML 1 & 2

Animation, JAVA behaviors, JavaScript, and sound are the differences between VRML 1 & 2. You should try to use whatever you can to make your site move!

BspTree Node

The BspTree is a preferment technique to reduce the amount of geometry passed to the rendering engine. Game Engines are typically based on some BspTree's logic. The BspTree is introduced as a native implemented VRML 2.0 node, other browser can display the model by using a PROTO implementation of the node.

A BSP tree allows us to make a world just about as big as we want without it slowing down the computer. To use a BSP tree think in terms of having your world cut up into a grid of tiles. Each tile can be thought of as a world in it self. So long as you put all your objects in a tile and don't have them overlap into any other tile it is easy to make big fast worlds. A BSP node is not a standard VRML97 node however it will be compatible with any VRML97 browser, you just wont get any speed performance gained unless you use a browser like Blaxxun Contact. Although this BSP Node was developed by Blaxxun for contact, BSP trees have been commonly used in computer games for some time that require large areas.

Are Spheres Faster than IndexedFaceSets?

Because I did low level programming in DirectX 3D before i ever new about VRML It never entered my mind that there would be any difference in the speed between a Sphere node and a IndexedFaceSet node in VRML. The reason I thought this was because when I programmed in Direct X there was no such thing as a function that would render a sphere only functions to render triangles. So it seemed only natural to assume that any shape that was more complex than a triangle had to be at some stage broken down into triangles.

Also your hear of video card performance being measured in triangles per second. If you press F7 in contact to see the performance info displayed at the bottom of your browser in the message bar you will see readouts of triangles regardless of what the shape is, be it a IndexedFaceSet or just a single Sphere.

Later I have wondered of the possibilities of the VRML 3d engine some how being able to take advantage of triangles being arranged in special case patterns such as spheres but I thought if this was the case I did not think there would be much to be gained.

Speeding Things Up Using Matrices

To my understanding VRML transform nodes have to keep being set up or at least watched by the 3d engine because all transform nodes can be potentially animated. Since setting up transform nodes are expensive on CPU processing power this is wasteful for objects that never need to be animated. One theoretical solution is to make each object in an IndexedFaceSet and position the coordinates where they are wanted globally so as to avoid any need for Transformations. This would in practice probably be awkward to do and could result in huge amounts of download time because there would be no downloaded data ever reused to make other objects. The solution here is to use the vrmlscript VrmlMatrix class to transform all your obj ects to where they are wanted just like you would when using a Transform node but the difference is its only done once when the world initializes.

How to build DOOM VRML worlds your self

Worlds for the DOOM II Game from ID-software are stored in a format that is convertible to VRML. In addition there are shareware and freeware tools available for editing and creating worlds for DOOM. First you need to have DOOM II.

Get a free DOOM WAD Editor and construct your own DOOM WAD-Worlds. WAD Files and editing programs can be found on the Internet by searching for sites via keywords like "wad", "doom".

Convert the WAD File to VRML using the Doom2Wrl program.

Doom 2 wrl was created by Ken Russel, SGI. We used a modified version for converting to the proper multi-user coordinate scale, the source is available as zip-file. (Microsoft Visual C and JPEG Library required for compilation.)

For tuned performance the generated VRML code can be BSP-Tree optimized for blaxxun Contact.

The source of Doom2Vrml could be further enhanced to support things, monsters, teleporters and so on. Currently only some doors can be opened with a click.

General

Look at your world through all monitors. If you have any friends with larger or smaller monitors, ask them to look at the scene.

Look at your world through different VRML browsers.

Reduce and simplify geometry.

Remove unneeded faces.

Use instancing (DEF once USE many Times).

Don't disable backface culling (solid FALSE) if it is not totally necessary.

General for blaxxun Contact 3D (but may also be true for other browsers)

Specify visibilityLimit in NavigationInfo for better z-range adoption and for more culled geometry.

Many Text Nodes are expensive, an alternative are textures representing text.

Few IndexedFaceSet's with many faces are more preferment than many single face.

IndexedFaceSets with few or only a single face.

If the plug-in is embedded into a frame set any animations like animated GIF's in the other frame may slowdown the 3D operation.

Flat shading can be forced with the default value for creaseAngle 0 and normalPerVertex FALSE.

For unlit materials use Material {diffuseColor 0 0 0 emissiveColoryourColorHere } The specularColor is already black by default. Prescale textures to a power of 2.

Specific to the blaxxun Contact 3D Direct 3D Version

If using many rectangles each with a different texture, try to combine several textures in one image, and adapt texture coordinates.

Color per vertex doesn't work in Direct3D Ramp Driver ("high speed"), in RGB/Hardware mode color per vertex Shapes are unlit.

Shapes with more than 1024 (hardware) / 2020 vertices (software) or color per face requires some extra preprocessing.

Animating vertex attributes (e.g. coordinates) of shapes works fastest up to the limit of 1024/2020 vertices try GIF Textures instead of JPEG's for Ramp Driver prefer modeling with convex polygons instead of generating an equivalent set of triangles.

Specific to OpenGL

If the model is targeted to run on a software only OpenGL platform or OpenGL hardware without texture acceleration:

  • Limit the amount of textures.
  • Prescale textures to a power of 2.
  • Use colors per face or color per vertex to add surface detail.

Other considerations

The "software only" rendering speed depends largely on the size of the rendering window. A VRML World could be presented using several viewing choices like:

  • A small VRML window embedded in a HTML page.
  • A full screen VRML link for users preferring full screen viewing or using hardware acceleration.
  • Fixed size windows or fixed size embeds (without %) are limiting the user to resize the rendering area. Other elements on the HTML-Page like animated-gif's may slowdown the VRML browser.
  • Another aspect is how the scene is decomposed for downloading. blaxxun Contact 3D starts the loading of Inlines and other nodes with URL fields in the order the children of Group nodes are specified, walking into the deeper levels first. Inlines in currently not traversed parts (e.g. non-active children of a Switch/LOD node etc.) are loaded if needed. In Internet Explorer Contact 3D starts the download of such in-active children if no other download activity is pending. For LOD nodes with direct Inline child nodes, Contact 3D will display the lower LOD-Level if the Inline is not loaded yet. BspTree nodes are traversed by default in front to back order with respect to the viewer.
  • Contact 3D currently does not unload nodes from memory. A script using node.addChildren/removeChildren Browser.createVrmlFromString could be used to perform scene memory management. A node is being deleted if no other reference exists to the node.

Specific to blaxxun Contact 3D vrmlscript/JavaScript interpreter speed

Minimize the number of eventOut's generated change an eventOut only if the value really changed (less redraw)

Original
 

x = 0; if (t>0.5) x=t; event = x; Better x = 0; if (t>0.5) { x=event=t; else if (x != 0) event = x;

Change an MF Event once at the end of the script and not individual elements in the body of a loop if applicable expensive calculations could be moved out of inner loops an initialize() script function can be used to set the startup state.


Did You Know?

  • VRML has the lowest number of programmers and is thought of by many as the wave of the future. And VRML may one day be the only programming used for 3D applications.

  • VRML is the ISO standard for 3D on the Web.

  • Important commercial companies are behind VRML - most notably its champion, Platinum Technologies.

  • VRML is a part of broader, next generation multimedia standards, such as MPEG-4.

  • OEM versions of Win98 ship with VRML pre-installed.

  • Free VRML viewers are available for most major platforms.

  • Sun's Java3D supports VRML as an interoperable 3D file format.

  • Platinum is developing the "unified browser" which will take mainstream VRML viewing to a new level of ubiquity, stability, and quality.

  • The installed base of VRML viewers was around 30 million in early 1998. One might surmise that close to half of Web users have some sort of VRML viewer installed in their main Web browser.

  • It has been rumored that future versions of AOL will incorporate VRML "out of the box".

  • The average $1000 desktop computer is quite capable of rendering fairly nice VRML worlds.

  • Most 3D tools support VRML, and there are a growing number of VRML-specific authoring tools.




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