Sub Hunter now available!

[ervin]

Well, I use CRTC &0C, &0D and &05 registers for smooth scrolling. And if you use a screen split, then you can realize parallax scrolling (Subhunter, 1943, Shadow of the beast demo). For what should you use the stack?
 
Stack it good to put sprites in the screen RAM, ok? But you're talking about scrolling.

The CRTC registers are beyond my abilities unfortunately. 
It's always interesting learning other techniques for such things though - thanks for the ideas.

[robcfg]

I can only say GOOD JOB!


It´s great to see new games with such quality.


Keep up the good work!

[ukmarkh]

So my crappy vid has finally been removed... maybe it's time I did a better one 

Just finished Sub Hunter, started playing at 16:00 and finished it about an hour ago. Good game and I've put a review up of it on my blog. Be careful though as I've included a screen shot of the last level and don't wanna spoil it for anyone.

[Axelay]

Ah, forgot to say last night, thanks for holding off on the long play video Xyphoe.

Gripes:
-no spot FX
-bloody difficult
-expensive! But I think I'll order both versions, it's kind of compulsive...

The spot FX were sacrificed because I didn't know how much memory there'd be.  In the end there was going to be enough space for them but T&J offered additional music instead and I happily accepted!    Having the new music in the bonus round helped to break up the sound track from the other levels.  In the C64 original the title music was used on some in-game levels, but this wasnt an option in my version really, partly because it was 50hz on the title screen while the game required 25hz music, but mostly because the title music is compressed when the game is running.  So it was kind of about trying to do one thing, the music, "right" by adding something to break it up, rather than squeeze in some possibly sparse effects and end up doing two things to a minimum.  Of course the "right" balance is down to personal preference too.  Sorry, seems to have turned into a lecture there! 

Ooh yes, that stack source code would be tremendous!
As you may know, I'm a big fan of stack (ab)use as well. It's the only way I know of to get a giant Savage moving smoothly around the screen!
 
Also, did you find Exomizer difficult to use?
It's something that may come in very handy for my game, but I've no idea how to use it. 

Original code for testing the concept attached, though I'm afraid the line by line commenting stops when my code starts  .  No problems using Exomizer, um, I think it was from cpcrulez I downloaded it, and it comes with instructions.  I'll have to check that was where I got it though.


As to TFMs question of "why" use the stack, well, mainly because it was an interesting idea.

[arnoldemu]

You used the stack for scrolling? Hmm. Wouldn't it be better to change the CRTC registers to realize the paralax scrolling? Or do I (looks like...) miss the point??

This would be possible, but drawing the sprites would be a headache because you would need to clip them for each scrolling part.

[arnoldemu]

So my crappy vid has finally been removed... maybe it's time I did a better one 

I removed it only because the static part had the text that disrespected the cpc 
A new video would be good.

[redbox]

As to TFMs question of "why" use the stack, well, mainly because it was an interesting idea.

You did it in software...?!  Amazing stuff.

[Optimus]

Wow! I remember when we were looking at Shadow of the Beast preview from Overflow and all we were thinking is if it could be used in a game to be put down that this is a demo and there is a lot of memory used and line syncing and a single sprite rendering code is running in parts between the syncing lines, etc, etc.


And then here it is! Is it 50 or 25 fps? I'd guess now 25 since you said the music had to also be 25hz, but anyways that doesn't show up, it's very smooth. I'd also guess 25 because I am surprised it's pure software, I have seen the posted code and I understand the technique of course and I know with a lot of consecutive PUSH to the videoram it's not possible to fill the entire CPC screen in 50hz but it is at 25hz (also not the entire 16k screen is filled in the game so there is time for additional sprites and still keep a decent speed). Also, the scrolling graphics tile on X very fast, so one can has PUSH HL/DE/BC/few more registers and have a repeatitive pattern scrolling in software. Cool!


It's funny to see it's all software, funny to hear it's even a 64k game. This is utterly impressive!
The game is not hard too, there are many different types of gameplay across the level and one just has to be careful to manuever quickly and precisely (I lost at first place at level 6, too early but it's just first time, one can become a pro and move further quite easilly).


It's great to see games showing up the capabilities of the CPC and it's even a good paradigm shift to show that scrolling can be done so well with just software rendering.

[ervin]

Original code for testing the concept attached, though I'm afraid the line by line commenting stops when my code starts     .  No problems using Exomizer, um, I think it was from cpcrulez I   downloaded it, and it comes with instructions.  I'll have to check that   was where I got it though.

 
  Fantastic, thanks for that. The code does indeed look very interesting.

[Nich]

Hands up who's pre-ordered a copy?

Me!

And Mark and Viddi too!

I've pre-ordered my copy as well!

Like everyone else who has posted on this thread, I also agree that this is a technically amazing game. The speed and smoothness of the parallax scrolling is incredible!

[TFM]

As to TFMs question of "why" use the stack, well, mainly because it was an interesting idea.

Software Scrolling    That makes your game even much more impressive.
 
Compared to the c64 version, I guess you completely had to rewrite it, do all sounds and gfx new. Or could you use "parts" of the c64 game?
 
Amazing work in incredible short time 

[TFM]

This would be possible, but drawing the sprites would be a headache because you would need to clip them for each scrolling part.

Yes right, but only few are moving actually fast. And with some "math" some will "swimm" as quick as the background. Having said this... the problem of splitting sprites between different scroll blocks (different speed) doesn't make it more easy, but I guess the scrolling itself would save a lot of time... Hmm... wished to have more time.... Wonderful game that :-)))

[Xyphoe]

Wow! At 1am views for my Sub Hunter vid were 290, and by 7am it had jumped another 100 to 390!

And it's made it onto the AtariAge forums again like R-Type - http://www.atariage.com/forums/topic/177261-sub-hunter-on-c64-now-ported-to-cpc-when-a8-version/

I like this persons quote on a possible A8 conversion -

"it looks like doable... at least the parallax could be improved..."

Hmmm! I don't think so or how they're expecting to improve(??) it!
Don't be bitter chaps!

[robcfg]

Well, the 8-bit Atari computers could do nice hardware scrolling, so a nice Atari version of Sub-hunter is perfectly doable.


I don't know if it would be better than the CPC version, but nice at least! 

[TMR]

Well, the 8-bit Atari computers could do nice hardware scrolling, so a nice Atari version of Sub-hunter is perfectly doable.

The hardware can do nice parallax with relative ease, but putting the sprites for something like Sub Hunter over the top of that is very likely to be an issue. The large sharks are about 24 pixels wide if memory serves and that's bigger than the entire A8 sprite hardware can manage on a scanline (four players and four missiles is 40 pixels, but they have to pair up to generate the colour so it's 20 if you want multi colour objects) - that means using software sprites (or preferably software with hardware sprites underlaid to give more colour) and the same issues about rendering across the zones apply - extra processing for different parts of the play area required in the rendering code.

[norecess]

Whatever which forums we are, when a game/production gets released, it always ends with technical discussion


So, I will get back to the roots : CONGRATULATIONS AXELAY (and friends ) for the game, it's marvelous !!

[EgoTrip]

This game is really good. Its great to see stuff that really does show off what the CPC is capable of. Puts the competition to shame for sure!

[Xifos]

Smooth software scrollings on the cpc !
At 25 hz ?
Amazing, great...
Axelay, does it mean we could have a new version of shadow of the beast at the same frame rate ?

[ukmarkh]

Chaps, I've updated my review of Sub Hunter. Please take a look, rate it and leave a comment if you like.
 
http://classicreplay.blogspot.com/2011/02/sub-hunter-amstrad-cpc-review.html#more
 
I've also heard a rumour that someone is working on a driving game for the CPC... will update as soon as I know more.

[jbaudrand]

very funny game. amazing technical feature, entertaining musics.
 
  what else?
 

[Devilmarkus]

Indeed!
Nice game for the CPC.
The technic is great (parallax scrolling) and the gameplay is interesting.

Thumbs up!

[Axelay]

Wow, what an amazing response!  Thank you all 

And then here it is! Is it 50 or 25 fps?

It's great to see games showing up the capabilities of the CPC and it's even a good paradigm shift to show that scrolling can be done so well with just software rendering.

Yes, 25fps.  I guess it is still worth remembering that using repeated blocks has it's limitations, but still, I previously wouldn't have considered software scrolling up to the task of 25fps in any meaningful way before, so it has been a learning exercise for me as well to try out this technique.

Compared to the c64 version, I guess you completely had to rewrite it, do all sounds and gfx new. Or could you use "parts" of the c64 game?
 

Primarily the graphics have been taken from the C64.  Most have been reworked to have a little additional colour, but the alterations were reasonably modest.  Some sprites had to be made a touch smaller, as my sprite size is 12x18 rather than the C64's 12x21 (I believe), and some sprites also got reduced to 11 pixels wide so they could have preshifted frames.

Axelay, does it mean we could have a new version of shadow of the beast at the same frame rate ?

Heh, well, this technique might well be able to be applied to the linear scrolling sections of SotB with some simplifications to that games backgrounds, but I'm not sure it would help much with the 8 way scrolling sections.   

[GFXOR]

It is a really good game. I hardly take time to play games, but this time was an exception. There is a very good finition, as usual in your prods.

Thank you for this game.

[mr_lou]

I also have to give my applause to this, yet another superb creation by Axelay. 
It's clear from initial loading time that it smells of professionalism. 

Very impressive MODE 1 scene where the sub goes down below surface.

Must admit, the gameplay in the game isn't the most interesting one to me. But that's not your fault of course, since you didn't invent the game as such. But it sure is a great port!

My favorite game is still Dead on Time, due to its complexity I think. Sub Hunter is more straight-forward. (There has to be something for everyone  ).

But once again, really great work. I've really glad to see that you're keeping yourself active. I hope you'll go on and produce more games for the CPC in that quality.

[Optimus]

Just a curious question. I know it could be a design decision taken from the C64 version. Why the scrolling from right to left?

Well, I am used to it now but I know other people who are curious about this design decision. Someone asked me if it was a technical limitation but I think both on CPC and C64 you can scroll both ways with the same ease. And we are used in left to right shoot em ups always, maybe it's the first time I played in the opposite way, so it seems strange to many people.

Do you know?