Scorpion Engine

[earok]

Latest experimental update:

- Mouse control is fixed to camera (essentially like the camera fixed movement).
- New "camera warp" option which instantly snaps camera from one side of the level to the other, taking all of the actors with it (mostly for infinite scrolling games).
- New racing demo (still a lot of work to be done on this, the UI isn't functional yet etc)

I was a little disappointed that I didn't manage to make that camera warp as seamless as I had intended. While the camera will snap instantly when doing a vertical movement, when doing a horizontal movement it still needs to do a full screen redraw (due to corkscrew scrolling) and thus introduces a frame skip or two on slower Amigas. (While the demo is vertically scrolling, it snaps left/right to switch to different road sections).

I might be able to solve that issue in future, maybe by blitting the entire buffer up or down to take into account the corkscrew scroll - but in any case, I intend to rewrite the top down racer demo anyway so that the tiles are regenerated on the fly. (and thus horizontally warping the camera won't be needed)

[earok]

Latest experimental update:

- Added Control#_MouseX and Control#_MouseY variables. The mouse movement type no longer uses VAR4/VAR5 for holding the screen relative mouse position, those are stored in those new variables.
- Removed ECSBorderBlank variable. Replaced with a Bplcon3 variable to give you full advanced control of that entire register (say, if you want to put sprites in borders, like in the above image, you'd do something like Bplcon3 = Bplcon3 + 2).
- Fixed bug reported by @Acidbottle CPU Wave didn't seem to be working as expected, in particular leaving an axis with a blank acceleration was meant to have the actor moving at a constant speed, not for them to hover in place.
- Fixed bug where changing blocks on the first frame of a loaded level could cause visual corruption.
- Improved safety for changing a whole bunch of blocks in a single frame - previously changing more than 64 onscreen tiles on a single frame could cause a crash, now there's no limit but it may trigger a full screen refresh if there's a lot changed at once.

[earok]

Latest check in:

Basically just reworked strings a bit, partly for the Mega Drive platform (now if you "quit" on a Mega Drive game, it'll print the quit string) but also for saving memory on the Amiga platform - I've reduced the string buffer by 9KB (!) and will probably trim it down a little more in future.

[earok]

https://cdn.discordapp.com/attachmen...345552/out.mp4

Latest check in:

- Major updates for the Scorpion Mega Drive output, it's still not yet viable for a game but many of the sample games will run at least in part (though there's known crashes I need to deal with). The above video was filmed with the Fusion Megadrive emulator. I'm hoping it won't be too long before, for example, Amigo the Fox can be converted almost entirely.

- Fix for issue reported by gleegum wherein animated blocks beyond a certain X position of the level wouldn't animate.

[skyzoo73]

i can't download the latest experimental, is the file corrupted ?

[earok]

@skyzoo it seems to be okay at my side? Do you use git to download experimental or directly via https://github.com/earok/scorpion-ed...heads/main.zip ?

In any case, I'm about to do an update anyway:

---



Latest experimental brings a handful of Mega Drive fixes:

- Fixed issue causing an instant crash in BlastEm! (Amusingly, this was because of Blitz Basic's linked list libraries attempting to disable the Amiga interrupts).
- Fixed issues with actors being rendered outside of the screen.
- Actor recycling should be working now.
- Fixed invisible animations.
- Fixed crash with Set Animation.

The state of progress is Amigo the Fox level 1 is playable start to end, though with a whole lot of caveats and glitches (namely that neither blocks nor events are working).

[earok]

Latest update:

Amiga improvements:
* Render Mode, Sprite Type and Multiplex settings can be set per frame rather than per animation. The point of this is you may (possibly) want to change the sprite palette across different frames of an animation, or use a sprite on some frames and a bob on others.

Mega Drive improvements:
* Blocks are working, including animations.
* Foreground implemented, including the ability to put Actors in front of the foreground by setting the Actor's Z value to greater than 1000. (For both tiles and sprites, this relies on the Mega Drive "priority" setting).
* Ability to set the palette line per sprite in an animation.
* Misc bug fixes, including a crash when attempting to trigger an attack on an actor that doesn't have an animation set.

[earok]

Latest experimental update:

Amiga improvements:
* Various bug fixes, in particular to do with sprite glitches.

Mega Drive improvements:
* Fixed bug where "invisible" blocks were wiping out the background tiles.
* Actors added with templates should be working, this is not tested.
* CPU_Path working.

Cross platform improvements:
* Bug reported by McCheeseBob, patrol and pursuit types were not working.

---

Audio is pretty much going to be the only part of Scorpion Engine that isn't similar on both platforms. I'm likely to use the MDSSRV sound library for the Mega Drive output, but given MML is (from what I understand) an entirely different paradigm to Tracker audio, there may be quite a learning curve for Protracker users to be able to bring their songs across.

---

Did a second daily update:

Mega Drive improvements:
* Fixed M68K alignment issue causing crash, and other crashes.
* Events Implemented.
* Panels wider than 256 pixels display in 320 wide mode, even if 256 is selected as the project X Resolution.
* Fade in / fade out.
* Prevent sprite from being clipped if too high or too far to the left on the screen.
* Fixes for sudden camera movements.

Cross platform improvements:
* Recycling is a bit less aggressive - actors have to be a little further away from the screen before they'll be frozen into the recycle state.

[earok]

Latest experimental update:

Been mostly focusing on streamlining input, it was bit of a mess and it needed to be tidied up before I can add button press events to the Mega drive output, but as part of that I've brought in a few improvements to the Amiga side.


Amiga improvements:

- "KeyboardRawCode" variable tells you the current key pressed/released.

https://whdload.de/docs/en/rawkey.html has an excellent list of Amiga KeyCodes in Hex format, to have a condition run on F1 pressed you could do:

if keyboardrawcode = 0x50
;I pressed F1
endif


Cross platform improvements:

- New Control#_Button contain the button state for the entire controller (previously, reading the CD32 exclusive buttons could only be done as an event during gameplay, now it can be done in any codeblock even when there's no level loaded). I'll make a codeblock at some point with the values to use for BITTST for testing if a particular button is down, but for now, the values are:

0 = Fire 1 / CD32 Red / Mega Drive B
1 = Fire 2 / CD32 Blue / Mega Drive C
2 = CD32 Play / Mega Drive A
3 = CD32 Reverse / Mega Drive Start
4 = CD32 Forward
5 = CD32 Green
6 = CD32 Yellow

(Note no support for six button Mega Drive pad - yet.)

- Panels expecting a button press can be dismissed with any gamepad button.


---

Did another quick update, I might have accidentally left the Mega Drive output in a broken state. Also sprites larger than 32x32 are working on Mega Drive now.

[earok]

Amiga improvements:

- Fix for bug where tiles wouldn't animate beyond a certain X position (related to previously reported issue where animated blocks would have the same problem).


Mega Drive improvements:

- Added support for animated tiles (currently excluding 'onanimframe' event, which I think nobody uses on animated tiles anyway, and the ability to change a tile's solid/platform states, which should come in future).

For memory reasons I've currently clamped this to 16 animations max in a level. I'll likely increase that in future but (unlike the Amiga output) there's going to be some hard limit on the number of animations you can have.

- Added support for setting the palette on a tile. Note that for maximum flexibility, you can do this individually for every 8x8 corner of a tile.

- Added support for setting the palette on a block. As per tiles, the palette can be set differently in all four 8x8 quadrants.

---

Emergency update:

Amiga improvements:

- Fix for keyboard and joystick event handling bug causing a crash.
- Fix for bug where the quit was showing a number rather than the actual message.
- Fix for similar bug for debug mode.

Mega Drive improvements:

- Hitting the reset button does a full memory wipe. While not doing that might have been useful for "X-Men" like chicanery, supporting it is probably more trouble than it's worth (especially since the Nomad and possibly other Mega Drive variants don't feature the reset button at all).
- Panels don't autogenerate palettes like they used to, they use the palette as defined in the image. It'll work out the appropriate palette line automatically.

[domkid]

Rick Dangerous Enhanced version on #Commodore #Amiga #CD32 / 1200 / Mini is finally out !
https://z-team.itch.io/rick-dangerous-amiga

[zzbylu]

A great game!
[ Show youtube player ]

[Aladin]

Thanks domkid

[earok]

Congratulations DomKid!

---



Been a few days since I've done an experimental update, but this one is a major. On the Mega Drive platform, massive progress has been made on stability and panels, though there's been a few universal updates for bugs affecting the Amiga side too.

The almost complete (excluding audio) Mega Drive build of Elf Spirit Hunters is included.

Mega Drive improvements:

- A LOT of stablity fixes.
- Partial support for most panel element and option settings, as can be seen in the screenshot we can have talkpads, number elements, counters and bars.
- Fixed bug wherein attempting to load or save on Mega Drive would crash. It still isn't supported, but it'll flag a load or save operation as failed, so you at least won't need to change your Amiga code to compensate for that.
- BlastEm, KEGA Fusion and GENS have buttons added for launching ROM.
- Added support for PAL 240 tall mode (if Y Resolution is set > 224).
- Fix for bug where level "On Timer" event wasn't triggering.
- Minor fixes with blocks (in particular, ones that didn't have a tile ID set wouldn't show on the map).
- SetColor commands working.
- A block that doesn't cover all four quadrants will not completely wipe out the background tile.
- Error given if the Y Resolution is an invalid value on Mega Drive (224 or 240 are the only valid ones).

Universal improvements:

- Fixed bug where the camera position would be reset to 0x0 before the level was fully unloaded (possibly triggering "out of screen" events before the next level was loaded)
- Completely replaced Blitz list commands with new ASM (based on the AmiBlitz 3 "fast" versions of those commands). This should yield slightly better performance all around.
- Fixes for CPU wave, in particular the wave movement stopping when colliding against a wall.
- Error given (at run time) if the map isn't as tall as the Y Resolution.
- "IsMegaDrive" and "IsAmiga" constants can be used to write conditions that are specifically for one or either of those platforms.

[earok]

Latest experimental update is a fairly substantial one.

Amiga improvements:
- Added horizontal scrolling OCS demo based on Ansimuz' Forest of Illusion art - https://ansimuz.itch.io/sunnyland-forest-of-illusion

Mega Drive improvements:
- Sound effects are implemented via the MDSDRV! There's also an "import" function that creates stand in MML wrappers around WAV files. Since all of the sound in Elf Spirit Hunters was effects only (no tracker music) I've included the latest version of that. I'll post a video explaining it all in a little while.
- Memory is properly blanked on startup (so if the memory is in a random state, it'll clean house before the splash screen is loaded).
- Counter divisions (for games like Zelda where a heart could be divided into multiple quadrants) property is working.

Universal improvements:
- Compile time error if a level is not as wide as the resolution.
- Image edit buttons for Fire Indicator and Choice Indicator (if a talkpad is used).
- Some improvements for parallax handling when doing a large and sudden camera movement.
- The "repeat delay" that determined when a sound could be repeated is set manually rather than automatically generated based on the sound length etc (eg, previously it was impossible to repeat a sound while the old sound was still playing, now you have full control over how often a sound can be repeated). This also takes into account the logic/output speeds for doing separate 25hz/50hz builds.


Edit: Video on Mega Drive audio in Scorpion Engine.

[ Show youtube player ]

[TCD]

Originally Posted by earok

That looks like Castle of Illusion++

[acidbottle]

indeed it is, Domkid did a demo using these assets a while back, with Mickey in it running around!

Great work on the MD front @earok. Is great Scorpion is going multiplatform, will hopefully get a few more folk involved

[captain]

Hi, I've posted this elsewhere, but realised that might be the right place. I'm working on an AGA game with a copper sky, but the sky colors gets heavily downgraded. Does anyone know which settings I need to apply, so that the copper sky appears smooth (24 bit)..? I'm using a 32x256 RGB png file in Scorpion Engine 2023 version.

It looks like the copper sky is being downgraded to 16 colors no matter which settings i apply...

[earok]

@TCD Ansimuz is one of my favorite Pixel artists, along with the BitBeamCannon team and Surt. They've done a few Mickey Mouse related asset packs as well as the art that is used in the "Gothicvania" demo.

Cheers @AcidBottle! I'm hoping it also brings Mega Drive users into the Amiga community.

@Captain AGA copper skies is indeed not supported right now. The main issue is that it takes four copper moves instead of one to do a 24 bit color change, which means it can't be done on index 0 unless border blank is used (which doesn't look good on a real monitor, example from the Turrican AGA project) or the colors stretch out past the graphics to the overscan edges.

If one or the other of those caveats is acceptable, I could look at implementing it again.

---

Two minor fixes for Mega Drive to experimental:

* Fixed bug wherein it would crash on BlastEm if the map height was below 16 tiles
* Fixed bug reported by DomKid where blank tiles quadrants would overwrite the palette lines of opaque tile quadrants below

[TCD]

Originally Posted by earok

@TCD Ansimuz is one of my favorite Pixel artists, along with the BitBeamCannon team and Surt. They've done a few Mickey Mouse related asset packs as well as the art that is used in the "Gothicvania" demo.

Just had a quick look on their website and it is indeed excellent work Looking forward to any update on that one!