Best technical and artistic tricks on the PCE

[Bonknuts]

Another thing I really like is the combination of colors used in LoT on the Dezant level. Also, the desert level in GoT. I found those particular choices to be excellent design from a color perspective.

 That level has a very nice special effect setup too. The first part, the desert sand, is dynamic tiles - not actual hsync scrolls. This allows the large sand beast to be mostly made of BG tiles too, and not all sprites (which would flicker like crazy). It's clever and brilliantly executed, giving the impressive of a large sprite or to a console programmer into that era of systems, who would normally think of that as a separate BG layer. So it's impressive on both perspectives because the PCE has neither the sprite bandwidth or the second hardware BG layer to pull that off. Yet you see it as is

I always thought the effect acheived in stage 3 of Metamor Jupiter was absolutely amazing!  The video doesn't do it justice, but in person it really makes you feel like you're in a rotating space ship or something.

 I like that trick too. It's a little more than just a BG linescroll X offset table. They also hsync update the BG color #0 (which nothing can be show behind it) to make a 2nd BG layer. Which definitely helps give the appearance that the canon is rotating. Honestly, the effect really wouldn't work that good without it. That technique of treating the BG color #0 as a special separate BG layer is fairly rare in PCE/TG games, but a handful others use it too.



 There is way too many to list and I'll let other people list the obvious impressive ones. So I'll mention Ninja Spirit. The effect isn't that spectacular looking, but the execution is one that surprised me the most out of all the games I've looked at on the PCE. The 2nd level. The forest level with the 2nd scrolling BG. For someone looking at special FX for PCE, it's pretty obvious that it's just dynamic tiles because it's a simple pattern and a pretty small one at that. But the surprising part isn't the dynamic tile, or that the dynamic tileset is rotated by the CPU in realtime (which is a little impressive considering most dynamic tilesets are prerendered). It's the fact that the game does a split level 2bit overlaid graphics manually. What does that mean? Look at the leaves of the trees. The dynamic tiles show through them. Yet, they're not sprite overlays. They also aren't special case of manual overlaid dynamic rotated tile onto these leave pixels either (which is what you would need to do on other systems, and by the cpu itself manually). Instead, the leaves use the upper 2bit planes of the tile and the 2nd BG layer via dynamic tiles uses the lower 2bits of the tile (a tile is 4bits for a total of 16 colors, 15 unique and 1 see through for low priority sprites or BG color #0). Through clever use and setup/structure of the palette (only needs to be setup once), the video hardware itself does the 2bit tile composite for the game. No cpu intervention or extra resource needed. That in and of itself is special, but the reason I found it extremely fascinating is that this is how I've done some specific special transparent graphic tricks on the PCE using the VDC as a hardware assist (akin to the Amiga doing it in some popular demos). And here I find a game that comes sooo close to doing it. I.e. They could have VERY easily made the leave 'pixels' transparent over the dynamic tile layer. But they didn't, of course. I don't know of any other game that does this type of setup (for hardware assist for transparency or even just simple overlaying). And I'm surprised IREM went to the lengths to set this up, but I'm also saddened that they never took the effect in the alternate direction for some really cool and complex transparency effects.

[fragmare]

Dracula X - Rondo Of Blood is an obvious choice... it's like a tour de force of artistic and clever bg/sprite tricks that make it seem like the system can do things it's not supposed to.

I've always thought the multidirectional software parallax in lv1 and lv2 of Ninja Spirit was both technically and visually impressive.  It's all done with tile animation, but it's so convincing that it's hardware-based parallax, somebody would have to point it out to you in detail to know that it wasn't.

All the games with tons of horizontal interrupt scrolling look great doing it (Coryoon, Air Zonk, Dead Moon, etc.) but it's no great technical feat.  In that same vein, the games that use line scrolling (like SFII' CE's floors) or sine wave effects (like the lv2 boss background in Sinistron) are always crowd pleasers.  All of these effects are essentially acheived the same way; by way of controlling the horizontal interrupt, sometimes on a per-scanline basis.

The "rolling barrell" effect in lv3 of Metamor Jupiter is pretty simple to do but also pretty nice eye candy.  As is the "horizon" effect from Chris Covell's Axelay demo.  They both use the same scanline trick, i believe. 

Also, some of the tricks used in Soldier Blade are pretty impressive.  The overpasses that "parallax" over the city, and the huge tank-like boss that is cleverly comprised of both tiles and sprites.  Not to mention the vertical "metal canyon" that uses faked column-scrolling when the huge crack in the Earth opens up.

The transparency effect in Jackie Chan is also very neat.

The rotating "Gunstar-style" title screen of Chris Covell's Tongueman's Logic is also pretty nice looking.  Makes the average person think, "Woa, the PCE can do THAT?!"

Not to blow my own horn, but I made some pretty neat effects for Xymati that are completely doable on the PCE...

[Keranu]

Another thing I really like is the combination of colors used in LoT on the Dezant level. Also, the desert level in GoT. I found those particular choices to be excellent design from a color perspective.

Totally agree with both of those. In fact, the desert level (Crown) in Gate of Thunder was what really inspired me to play that game ever since I saw it in one of those Duo promo videos. Of course being the dork that I am, I like to pretend that level was a tribute to Insector X .

[Digi.k]

BTW are those real vector graphics at the intro of space invaders Fukkatsu No Hi ?? because I love them even tho it's very short

[Black Tiger]

BTW are those real vector graphics at the intro of space invaders Fukkatsu No Hi ?? because I love them even tho it's very short

A hardcore vector fan would point out that true vector graphics require a vector screen. I've also wondered if those wire frame animations were done in real-time. I think that I asked about it in an "how'd they that?" thread I started a long time ago, but never got an answer.

[sunteam_paul]

Someone needs to dig deep into the PCE wireframe capabilities. Who knows what the machine could really do if it were pushed?
(hopefully the answer isn't: not much).

[SignOfZeta]

Has anyone ever explained, or even come up with a name for, the weird BG effect that is present in Vasteel's battle scenes? Its also used a lot in the backgrounds of the cinemas in one of the Ranma games.

[Black Tiger]

Someone needs to dig deep into the PCE wireframe capabilities. Who knows what the machine could really do if it were pushed?
(hopefully the answer isn't: not much).

I don't know how taxing wire frame 3D is compared to polygons, but I'm guessing its easier since the former predates the latter for common use. Considering the polygonal stuff that has been done in Genesis and Turbo games, I'm assuming that they should be able to do some decent wire frame stuff.

[ccovell]

Has anyone ever explained, or even come up with a name for, the weird BG effect that is present in Vasteel's battle scenes? Its also used a lot in the backgrounds of the cinemas in one of the Ranma games.

It's still just line scrolling / raster effects, with a simple sine wave horizontally, and stretching / compression vertically.

[TheOldMan]

I don't know how taxing wire frame 3D is compared to polygons...

Wireframes are easier, if you don't mind background wires showing through. It gets a bit harder if you want them erased - at that point, it's not much different from a black-filled polygon.

I'm assuming that they should be able to do some decent wire frame stuff.

Possibly, assuming you don't need a high frame rate.
In one test Arkhan and I did (for the vines in junglehunt), we managed to get 5 lines moving before hitting the frame time limit. The problem is that the pce has a 4-plane BG layer, so drawing 1 dot involves 4 read/update/write cycles. Add in the need for floating point math (faked or not), and you can see it's a problem.
Not saying impossible, but it looks like it would take a hell of a lot of optimization to get anything above about 15 fps for more than a dozen or so lines....

[nodtveidt]

Doing wireframe on the PCE isn't necessarily easy but it's not tremendously hard either. It's hard to do it *fast* on a large scale in realtime. It also depends on whether you're doing it on tiles or sprites, as the memory layout is a little different between the two. The PCE doesn't have, as far as I know, any direct bitmap modes, so you need to draw pixels in whichever memory arrangement you're going to use, either tiles or sprites. It's tricky because you have to account for surrounding pixels, which means you're going to have to do some bitwise maths. It can be slow, especially if you're doing multiple colors and especially if you're trying to cover a large area. HuC's standard library has a method of setting up a pseudo-bitmap mode, but it's really just a few high-level functions that manipulate tile memory and these functions are sloooooooow despite being written entirely in assembly.

I would surmise that doing wireframe on a screen composed entirely of sprites would be easier due to the difference in memory model, but that's just an educated guess.

EDIT: And what TheOldMan said.

[Arkhan]

I fiddledicked with doing 3D wireframe stuff on the PCE one time (tried drawing the standard Teapot using the dataset, and fixing it all to a 2D plane).

It went poorly.  The lack of a bitmapped mode, coupled with the 6502ness, and HuC, made it a daunting task.   Drawing lines and junk on a sprite/tile based system is pretty mentaltarded.

Also, I am talking a proper teapot wireframe, including only showing what should be visible. 

If you want a better idea of how herp to the derp it will all turn out, check out the line-based C64 games.  It goes a little like that.

I bet if I molested it enough, I could get the teapot working good and maybe even shade it or at least fill the thing in...

but the practicality of it doesn't exist.  After you're done maiming the CPU drawing the thing, you'll have no juice left to do anything useful.  its not really worth even doing.  Prerender the crap as sprites.

As for the Vasteel effect:

The technical term I use is "wigglejiggle"

[TheOldMan]

I would surmise that doing wireframe on a screen composed entirely of sprites would be easier

Easier, yes. But a bit slower. (And you have to fight the line limit with sprites).

There are differences between sprites and tiles; but except for a slight difference in the memory layout, they are pretty close.
It turns out that it's actually faster to use tiles than sprites. Why? Because when you are using tiles, the color planes are 'paired'; there are two sets of bits next to each other in memory for the tiles. This allows you to increment to get to the next plane of the pair. With sprites, the planes are at a fixed offset from each other (32 bytes, I -think-. Don't yell if I got it wrong, bonknauts). So, to go from one plane to another, you have to do an add, which takes longer . Of course, you still have to do 1 addition when you move to the next plane pair using tiles, but that's better than 3.

Yes, this is seriously true. The time for setting 1 dot on an overhead map using sprites is actually longer than doing the same thing using fixed tiles. Unrolling the plane loop and using an increment saved about 6 cycles per dot. All the other code was exactly the same (we started with sprites). That was enough of a difference to stop frame timeouts when we updated the overhead map (which had 8 dots to be turned off, and turned on again in another spot).

[Arkhan]

The difference being, Sprites let you get some transparency!  Vines drawn in the background would result in alot of effort to make nice backgrounds.
 

[spenoza]

Well now, didn't Gunboat and some air combat game use simple polygons? If you can do simple polygons you should be able to do simple wireframes.