Question regarding a 3D game engine for lasers

[masterpj]

I'm currently on a laptop.
my pc will be upgraded with a new motherboard and a new case on tuesday.
No reinstallations needed

so I just got a reply from someone on my youtube who knows how to get the 3D coordinates and how to convert them to X and Y data.

the requirements will be pixel shader 3.0 for a video card though
It's possible with PS 2.0 but PS 3.0 makes it alot easier.

In other words:
I found the right way to convert an XNA 3D game to a laser projector.
The thing is that it still needs to be made, and thats what I'm going to do soon

Happy new year everyone,

Pieter

[JohnYayas]

XNA may be what you want but also check out SlimDX. It's a managed (ie .NET) interface to DirectX.

[masterpj]

XNA may be what you want but also check out SlimDX. It's a managed (ie .NET) interface to DirectX.

Aha
will do
just a question though, is there a certain advantage of directX in this case?
I do know XNA programs are xbox360 and windows compatible only.
off course I will not be using an xbox360

[JohnYayas]

For a laser game, you don't need DirectX for output but you can use some of the 3D matrix manipulation routines for computation. You could also use it if you are offering some sort of preview window on the screen. But, for just sending data to your scanner, DirectX does nothing for you. There are other matrix packages available and you can even roll your own so it's up to you. I am not entirely sure what all XNA offers. I know if offers ways to easily add sound to your application and probably other things to make game writing easier. If I was creating a game I'd definitely look into XNA a lot. But, if I just needed some routines to manipulate objects in 3D I would go with somethine else.

[masterpj]

XNA offers the things needed and give the ability too for on screen preview and also off course the ability to play on the laser scanner without the screen
(Im going to do both), you can just toggle the screen to black and then you play from the scanner only instead of both.

XNA is easier to use and program is being said.
Only problem is that you aren't allowed to share the .dll's commercially but only the runtime I heard.

Off course I hadn't planned it to be commercial but Depending on the time needed in the end I might do that.
But that limit sounds like a trade-off you have over the control of the final application, A bit sad of microsoft that they had to do that, but maybe there is no reason for worry or a bypass.
At the moment it's no problem but it sounds like I need to watch out for Microsofts restrictions

*edit sadly that developer couldn't help me but he pointed me in the right way*:

"Cheers for commenting. Wish I could help more, unforuntately I am working on the practical component of my dissertation for the next 6 months. Getting screen co-ordinates is often usefull in a fragment shader, most books on HLSL will tell you how to calculate it. Best of luck!"

[allthatwhichis]

Ewwwwwww... Matracies... . Hate those things. Why don't you take a real 3d game engine and write a wrapper to convert the coordinates to something ILDAlike...

[masterpj]

Ewwwwwww... Matracies... . Hate those things. Why don't you take a real 3d game engine and write a wrapper to convert the coordinates to something ILDAlike...

Writting a wrapper is even harder.
3D games often have too many objects or unneficient placement of objects,
getting outlines of those can also make games unplayable because of too much flicker or you just have no clue what you are doing.

Matracies?

Also an engine more specificly made for this has an advantage over having more control over things.

Ildalike? It needs to provide output to a laser projector and realtime.
Off course it will have some information that can be compared to normal ilda but has to be send directly to a laser projector.

I will be pointless if you can save it to ilda as you are supposed for example to play a game.

Even though I might make ilda output later, but I don't have it planned yet.

I should also say that this is not only ment to be a 3D game engine but overal just a 3D engine for laser that actually can be used with normal 3D programming language.

Il give you an example.
What if a 3D character in a lasershow can interact with you? or interact with the nearest person in its view?

The thing I will have availble very very soon though you need to have pangolin LC-max is realtime 3D motion capture with kinect.

[DMills]

The big problem with off the shelf 3d is that it generally does not make getting at the transformed vertex data in a way that is useful easy (And the shaders and such are largely inappropriate to this use).

GL can do it, but it is sufficiently nasty that you are better off just doing the transforms yourself (not actually that hard).

The lions share of a real 3d game engine however is NOT really concerned directly with 3d rendering, but with 3d visibility, things like BSP trees (Data reduction and hidden surface removal) and PV (Further data reduction) sets, which unfortunately get sufficiently entrained with the rendering code as to make extracting the bits you can use harder then just penning your own version.

Most higher level 3d engines assume that painting order will remove the hidden surfaces and lines (not true for lasers).

Seriously affine transforms (as most are) are just not that hard.

Of course once you have sets of vertex data you need to render the scene into laser points, and that can be where having a higher level representation can be good as triangles are not actually favourite for many laser projection applications (not smooth, if you say tessalate a sphere with triangles and trace between the vertices you get wavy lines, annoying).

Carmack has some good papers on software 3d engine design.

Regards, Dan.

[masterpj]

Where can I find carmack?

With GL you likely mean OpenGL...
Well thats ok but I'm not able to program well in C++ at the moment.

I can do VB and C#
OpenGL is C++
I heard some things about some C++ for C# abilities ( if it's worth it thats a different story)

with the object distance I think i just get the relative distance where the camera is positioned from the center and make it so that all objects within a certain radius from it only appear.
The objects which are not in the FOV ( field of view) will not be rendered and calculated.

I try to get the outline coordinates of objects only.
I'm putting alot of optimizations at a lower priority and try to focus on the actuall output itself first.

Using a 3D engine often involves these problems:
- bad documentation at times
- hard to puzzle it out to get to functions you actually want.
- bad quality or not free
- needs license to spread or anything in those lines
- often not every part of it's source and also gameplay itself is harder to adjust.

However I do like the information members provide me here, it can be usefull at making decisions or prevent getting way off track

[allthatwhichis]

Where can I find carmack?

http://en.wikipedia.org/wiki/John_D._Carmack