More Impressive 3D Engine: Rebellion vs. ID

[Optimus]

I wanna add that technically Doom is not a raycaster. It's not true 3D either.

But the term raycaster is about casting rays and see if it hits walls.

Wolfenstein was a raycaster.

Both Wolfenstein and Doom rendered walls by drawing stretched vertical columns. But Wolfenstein determined what columns to render with what stretch with raycasting. Doom determined which wall sections were visible with BSP trees.

 

Fun surprising fact, the SNES version of Wolfenstein is based on BSP trees, because raycasting was too slow for it. I heard on the video where Carmack plays Wolfenstein and comments on it.

 

Anyway, this makes both AVP and Doom not able to have true 3d maps with stacks of floors one above the other (even though you can fake it with teleporters like in Duke Nukem 3D, which uses portals instead of BSPs)

 

But AVP to me looks like wolfenstein 90 degrees walls. And Doom has much more interesting 3d spaces and diverse textures. I definitely found the Doom engine quite impressed on my Jaguar. I see now it's more lowres (it's like the F5 low detail mode from PC) which I didn't noticed in my noisy TV set up. But still it really impresses me. It might not be real 3d, but at the end it's another clever way to render 3d worlds and it might even look more fabulous than some true polygonal 3d games. Also because of the great level design.

 

I haven't checked other real polygonal games though yet, besides Club Drive and Cybermorph. I missed the good ones so far (more expensive to get at ebay).

[Chilly Willy]

Actually, Doom IS a raycaster. What is different is the method used to determine the intercept points with walls. Wolf3D uses a regular grid to represent walls, while Doom uses a BSP tree. Each ray is cast like a normal raycaster, then for each sector the ray enters, line intersection calculations are done between the ray and each line segment inside the sector. If there is no intersection, or if the line segment indicates the wall isn't solid, the ray is advanced to the next sector along the ray's path, and the intersection check is done again. The BSP tree merely makes finding which sector the ray is in faster given arbitrary shaped sectors.

[Optimus]

Actually, Doom IS a raycaster. What is different is the method used to determine the intercept points with walls. Wolf3D uses a regular grid to represent walls, while Doom uses a BSP tree. Each ray is cast like a normal raycaster, then for each sector the ray enters, line intersection calculations are done between the ray and each line segment inside the sector. If there is no intersection, or if the line segment indicates the wall isn't solid, the ray is advanced to the next sector along the ray's path, and the intersection check is done again. The BSP tree merely makes finding which sector the ray is in faster given arbitrary shaped sectors.

 

I gotta then check the code to see what's going on.

From some coding folks I get that still it's not a raycaster, they just find which wall segments are visible through BSP and project the walls/colums on the screen, but not mention raycasting.

This code review explains some stuff but not mention raycasting at all. At some point it says "Visible SEGS are projected on screen via a lookup table and clipped via an occlusion array."

 

I think I will study more this site (if I have time) and maybe look at the code for any signs.

[Chilly Willy]

I gotta then check the code to see what's going on.

From some coding folks I get that still it's not a raycaster, they just find which wall segments are visible through BSP and project the walls/colums on the screen, but not mention raycasting.

This code review explains some stuff but not mention raycasting at all. At some point it says "Visible SEGS are projected on screen via a lookup table and clipped via an occlusion array."

 

I think I will study more this site (if I have time) and maybe look at the code for any signs.

Uhg... must be getting old or something. The way it works is like this:

 

It goes through the bsp tree looking for sectors on the same side of the player as the way he's looking. If a subsector is found, the segments are all checked. Each line segment has its start and end view angles computed, which are clipped to the angles corresponding to the screen. The line segment and clipped start and end x coords are stored for later.

 

So it really isn't a raycaster in the traditional sense. Sorry about the confusion... most of which was my own.

Edited December 14, 2014 by Chilly Willy

[Optimus]

Yeah, I thoroughly checked the code and that's what it seems to be doing.

[NeoGeoNinja]

I haven't checked other real polygonal games though yet, besides Club Drive and Cybermorph. I missed the good ones so far (more expensive to get at ebay).

 

Be sure to put:

 

Iron Soldier, Iron Soldier 2 & Skyhammer on your list of 'impressive' 3D showcases for Jaguar.

[Lost Dragon]

Impressive 3D engines on any platform, are fantastic in terms of showcasing the power of your hardware, marketing love'em etc, but..as i hinted at in the other thread, about developers 'maxxing out' the Jaguar hardware, they are not the be all and end all.

 

Rogue Squadron 3 on GameCube looked stunning, but it's my least played G.C title as it plays like an utter dog, PS2 Gran Turismo looked fantastic, but 1st PS2 incarnation alone was using A.I code (and sound fx in places) from the PS1 game and Lair on PS3 might have run at 1080P (great achivement for an early PS2 game) but i found unplayable.

 

The Jaguar Iron Solider games whilst boasting impressive 3D engines for the hardware, really nailed the all essential 'feel' of being in a all powerful Mech, with you crushing tanks under foot, blasting pesky helicopters from the sky etc....

[NeoGeoNinja]

PS2 Gran Turismo looked fantastic, but 1st PS2 incarnation alone was using A.I code (and sound fx in places) from the PS1 game...

 

Personally, GT1 & GT2 on PS1 are still - head and shoulders - my favourites in the series. The series felt really soulless by the time it hit PS2, although, I really did enjoy the Rallying segments from GT3.

 

I genuinely believe Polyphony could have made an amazing stand-alone rally title (WRC licensed GT title?) based on how that part played alone. It really was that under-utilised and that good.

 

Also, as a little side note: The Japanese release of GT4 can be run at a staggering 1080i, should you wish to do so! Pretty impressive...

[Lost Dragon]

:-) Don't mind me, i hate driving in real life, so only really 'took' to racers like Pitstop 2 (C64), Buggy Boy (C64), later Burnout Series (all pre-Paradise), and Blur on PS3.

 

 

The G.T series i look on with some bemusement.Fantastic graphical showcases as far as PS1 and PS2 era went, series lost it's way on PS3 it seems, but for a 'Real Driving Sim' it often seemed anything but-No car damage and for a PS2 title, after all Sonys hype of the raw power of the system, to use PS1 Logic routines for it's A.I, i could never quite get over, but then PS2 does in effect have 2 PS1 Soundchips side by side, so it's far from only thing Sony kept from the PS1 era :-)

[NeoGeoNinja]

:-) Don't mind me, i hate driving in real life, so only really 'took' to racers like Pitstop 2 (C64), Buggy Boy (C64), later Burnout Series (all pre-Paradise), and Blur on PS3.

 

YES! Blur was excellent! A really executed game all round imo. Just a shame I could never get it to work online. Incidentally, I never bother playing games online, but enjoyed that game enough to want to do so. Horrifically overlooked gem imo.

 

Also, I never did rate GT's so-called 'A.I.'. Just an exact row of vehicles that follow the exact racing line of all the tracks, with no actual intelligence to be had whatsoever...

[Lost Dragon]

Ohhh man, Blur online (PS3) Utter carnage, but thus UTTER BRILLANCE.The most all out fun i'd had playing online, ever (The Soul's games were more serious).It simply just worked.

 

Last time i tried it online (months ago) servers deserted except for a core of ohh so clinical (and serious) german gamers.Not the same exp.by a long shot....

 

:-)