Camera perspective (image incl.)

[Tom Hatfield]

This image is served from my web server. It should be available 9am to 12am EST. Please tell me what you think of the camera perspective. (Comments on the scenery itself are welcome but not necessary. This scene is only to test the camera.)

http://three.homeip.net/images/dmc_01.jpg

Placing the camera for a DM clone is not as easy as you'd think. On one hand, you want the perspective to feel natural. On the other hand, you want the graphics to conform to some arbitrary size that is easy to manage and post-process. Granted, the best camera FOV for post-processing is 90 degrees, but it looks extremely stretched and unnatural. I went with 45 degrees on this one, and I think it looks pretty good.

The tiles do not conform exactly as I'd like. I would prefer using mip-maps to represent tiles of smaller sizes. With a 90 degree camera I could do this, but the tiles in this particular shot don't fit inside each other correctly. (I thought about providing a schematic from max to demonstrate this, but it's not that important.) I'm more concerned about looks.

Anyway, please post your comments. I'd like to read them.

[Tom Hatfield]

Here's the same scene in another aspect ratio. I'll probably use this one since it can be stretched to fill the screen, although it does complicate how I store the graphics. I've tinted every other tile so you can distinguish between them, giving you a better feel for the perspective.

[Gambit37]

I prefer the second one. Because you don't see the very top of the walls, it's more like DM -- feels as if the floor and ceiling are closer => more claustrophobic => better atmosphere.

Are these real 3D objects, or just bump mapped graphics? They have loads of depth and look great!

Vist the new Dungeon Master Codex website, coming soon!
http://www.dmcodex.com

[Tom Hatfield]

Sorry about the server being down. I slept in today, and then I had to shut down the server due to software conflicts. Everything is fine now.

I enjoy the claustrophic feel, too. DM was actually the opposite: the floor and ceiling overlapped the edges of the screen, making the ceiling look very low. I like the above technique much better.

Displacement maps give the textures depth. It's rendered as actual geometry, but it's processed on-the-fly rather than all-at-once, so it goes pretty fast. You can see a high detail version here: http://three.homeip.net/images/dmc_huge.jpg (134 KB). Camera is the same, but I tweaked the lighting.

Due to the difficulty of hacking these scenes up and making tileable images out of them, I'm considering rendering stills with transitive animations (like the 7th Guest, Blackstone, etc.) and making something more akin to Shadowgate.

Also, these textures have to go. I'll be replacing them with better ones in the future.

[Gambit37]

I think you'll find DM is actually more like your second example than you realise, well, close to the floor anyway:

http://www.gamedev.net/reference/design ... ure7-9.jpg

Really love that rocky floor and ceiling, can't wait to play a game with that level of detail!

Vist the new Dungeon Master Codex website, coming soon!
http://www.dmcodex.com

[Tom Hatfield]

Hmm. My memory wasn't up to par. They placed the camera closer to the ceiling to give the impression of height. I tested this myself, but in my case it looks better centered.

I replaced the original image on my web server, so the one here is obviously going to reflect that.

Server times are Indiana (-5:00 consistent). Sorry I forgot to mention that.

[beowuuf]

It's funny, while it is nicely chlostrophoebic (gah, spelling's overrated) it felt strange, as the party almost touching the ceiling view made the corridors too small, or the party too tall

I like how you've placed the camera, the ceiling seems the right height now, while keeping the squuezed corridors

and i love the small step transition between the walls and ceiling/floor, and very nice lighting, very atmospheric - what will actually be in place of the light sources in the end? torches? It might be great to reduce the lighting points in a dungeon - so that you go in and out of shadows - who knows what small nasty can be waiting in the blanks, until you get a light spell!

[Tom Hatfield]

Torches, gas lamps, faeries trapped in glass bulbs -- obviously it would differ depending on where you are. Of course there will be fewer lights in most dungeon areas. The distant between floor and ceiling would also vary. In the scene above, the ceiling it exactly 2 meters above the floor. Here's another scene, much darker than the last, with the ceiling only 1.7 meters high (approximate DM height):

http://three.homeip.net/images/dmcnew01.jpg

I left the seams between tiles so you can tell them about. I'll remove them when it comes time to do final grapics. Here's another one with only the torch:

http://three.homeip.net/images/dmcnew02.jpg

It really accentuates the roughness of the walls. With this kind of lighting, a tile engine really is out of the question. It would be possible to achieve similar effects in real-time using the latest shader technology and hardware, but that's not a route I plan to take.

Thanks for the feedback. It's very inspiring to know that people are interested in the project.

[Gambit37]

Drooooool!! Lovely looking graphics (though I think the walls look a bit odd -- not final images though, right?).

I know very little about 3D engines, but I'm interested on what kind of hardware will be required to run your engine. I mean, if the floors and walls are actual geometry, doesn't that put a huge amount of strain on the graphics card? It looks like the floors are quite complex objects...

Vist the new Dungeon Master Codex website, coming soon!
http://www.dmcodex.com

[Tom Hatfield]

No, it wouldn't be geometry. The new 2.0 and 3.0 pixel shaders are powerful enough to handle all sorts of wonderful things, one of which is real-time virtual displacement mapping. It's not real displacement, but it looks convincing at reasonable angles. This technology has been demonstrated in the upcoming Unreal 3 engine.

These are not final images, no. What precisely do you think is wrong with the walls?

[Gambit37]

Difficult to comment on the walls at present, as images aren't available, but as I recall the depth of shadows was quite pronounced, and the bricks were quite regular in shape -- the two things together just looked a bit unreal (no pun intended). I think it's just a case of having less regular looking bricks, maybe with less space between them.

Vist the new Dungeon Master Codex website, coming soon!
http://www.dmcodex.com

[Tom Hatfield]

I went to bed at 10:30 last night, so I shut down my system early. I wasn't feeling very well.

The bricks are indeed more pronounced than I would like. They protrude from the wall about 5 cm. In real life, that's about the size of a brick. Some ambient light would take care of the shadow problem, but I need to go back and redo the displacement map altogether.

Also, the scene in the last picture above has only one light, which is unrealistic without any global illumination or ambient light of some kind. Practical scenes should have at least two or three lights.

[Gambit37]

I just downloaded and watched the Unreal 3 tech demo video from E3. Very impressive indeed! I understand better now how flat textures are given depth using maps. But I don't know enough... where is the best place to learn about this? I have the PLE version of Maya 4.5 but have never learnt 3D, though I would very much like to. From what I've read here, and over at the other forums, the whole thing about lighting and mapping seems very complex in itself, let alone actual modelling.

Any good tutorial sites around or free info?

[Tom Hatfield]

Are you talking about 3D concepts in general, or virtual displacement mapping in particular? For the latter, you should google a document called "Parallax Mapping with Offset Limiting." It describes the math and principles behind VDM and provides fragment shader programs that will get the job done.

I believe Far Cry also uses parallax mapping if you have a card that supports it. Unfortunately, I'm stuck with ps1.x at the moment (which is one of many reasons I want to avoid a true 3D engine).

[Gambit37]

A bit of both.

I know 3D concepts, even though I've never done any significant 3D work myself. I feel I understand coordinate spaces, basic modelling, texture mapping, etc to not need an intro to them.

But I have no idea the difference between displacement, diffuse and normal maps, and the lighting stuff you're talking about. I'd like to know more about that if there are some good places on the web to start....?

Vist the new Dungeon Master Codex website, coming soon!
http://www.dmcodex.com

[Tom Hatfield]

A diffuse map is just a color map.

A displacement map is any texture map used to calculate the offset of tesselated geometry during displacement. (The process of displacement involves tesselating geometry and then offsetting the tesselated portions to produce greater surface detail.) You would normally do this with a grayscale bump map.

(This description is redundant, as bump maps are grayscale by definition. You could, of course, write software to use various color channels during displacement, but conventially we use the brightness channel. The best representation of this is to use a grayscale image.)

Normal maps store pre-calculated normal data at the texel level. The term "normal map" is not necessarily synonymous with "bump map," as normal maps serve a wide variety of uses, but it is possible to use a normal map as a bump map if your software supports it. Generally, normal maps are calculated in object space rather than texture space. They are used to simulate geometric detail where providing actual geometry would be unreasonable (the same way a bump map simulates roughness).

The advantage of using normal maps over bump maps is, of course, that they are pre-calculated. NVidia long ago released a plugin for Photoshop that will convert bump maps into normal maps. DarkTree 2.5 is capable of rendering either normal or bump maps, depending on your preference, using the same texture data.

Traditionally, the red channel in a normal map represents the U (horizontal) magnitude component in an offset vector, while the green channel represents the V (vertical) component. (The blue channel may serve a variety of uses, or it may be ignored altogether.) As you would expect, these values have 256 degrees of accuracy across a 180-degree arc.

I hope this helps in your understanding of 3D graphics. It's not much.

[AndyWatts]

Hurendo-san,

Just wanted to say I like the screens you've uploaded.
I've been trying to implement a couple of DM levels in unreal myself, mostly as a learning exercise.

Hope you continue with this and I look forward to seeing things develop.
Is http://three.homeip.net your main site for this?

- Andy

[Tom Hatfield]

Thanks for the comment. Yes, that's my site, but I should mention: it'll be shut down on the 21st of June (two days from this post). I may be able to coerce one of my friends in maintaining the server for me.