Scorpion Engine

[earok]

@TCD I'm not sure if I'll do any more on it, but I wouldn't be surprised if DomKid does


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Latest experimental -

Amiga improvements:
- Backported slightly more optimal animated tile routine from Mega Drive port to Amiga.

Mega Drive improvements:
- Support for second player. Three-eight player support might come in future but that's a very low priority right now.
- Fixed bug where levels with multiple tile animations would be broken.
- Patterns are loaded with DMA transfers (with handling for any transfers that cross the 128KB threshold), also MDSSRV is configured with 100 bytes of DMA protection.
- Added support for camera "warp" function (as such, the vertical car demo should work on Mega Drive with some tweaking).
- Block and tile data is implode crunched (Slightly smaller ROM files).
- Some fixes for talkpad handling
- Slight tweak to scrolling for 240 tall mode

Universal improvements:
- New "control bits" codeblock contains the constants for all Amiga/CD32 and Mega Drive control buttons (excluding MD six button pad)
- Panels can be specified whether they are top, bottom or "fullscreen middle" panels. This isn't strictly enforced (eg, you can still load a "top panel" on the bottom if you wish), it's mostly because there's a plan to extend the panel system for use on things that aren't, strictly speaking, panels (eg, parallax backgrounds).
- As the "talkpad on bottom" setting is redundant, it's been removed.

[earok]

Latest experimental:

Amiga improvements:

- Added new "pause" default codeblock which will wait until the user presses the P key before resuming gameplay. Later on this will be expanded to support the CD32 Play button and the Mega Drive start button.


Mega Drive improvements:

- Some fixes for talkpad.
- Fix for bug where fullscreen element would blink on load.
- Added support for animated options.
- Play sound command should work with the trigger attack sound and trigger jump sound.


Universal improvements:

- Added ability to open/edit Option Images in editor.
- Some optimisations for panels (in particular, when two panel elements overlap, it only does the "clear" restore once rather than twice.)
- Destroyed actors no longer trigger a collision on the frame that they're destroyed.
- "Option move cooldown" is exposed to codeblocks. By default, it takes 25 frames before the option on a panel can be moved by a joystick held in one direction, this can be increased or decreased if need be.
- Bug fix with CPU_Wave type (specifically bug with setting move direction to upleft/up/upright)

[earok]

Latest experimental update is mostly to try and make the Mega Drive side a little more stable, performant and less flickery by shunting most of the drawing operations to the VBlank, though there's a couple of general editor improvements too.

(I do want to apologise that there hasn't been a lot in the way of the Amiga side lately, the current state of things is that the Mega Drive side is *far* behind the Amiga side in terms of capability so there's a lot of catch up to do).

Mega Drive improvements:

- Fixed potential bug where animated blocks could continue animating even when they're well outside of the display area.
- Fix for bug where fading in a panel would crash the game.
- Tile scrolling is in the Vertical blank.
- Sprites are set during Vertical blank (using DMA).
- Tiles are animated in the Vertical blank (using DMA).
- Blocks are updated in the Vertical blank.
- Bug fixes for DMA transfers.
- Limited support for a top panel and the middle panel simultaneously (or the bottom panel and the middle panel). Note that a top AND bottom panel simultaneously isn't supported because of Mega Drive limitations.

Universal improvements:

- Added ability to open the counter and bar images from within the editor.

[pixie]

Originally Posted by earok

Latest experimental update is a fairly substantial one.

Amiga improvements:
- Added horizontal scrolling OCS demo based on Ansimuz' Forest of Illusion art -

Is this on Amiga? Would it be possible to use copper to extend the detail in trees, grass, terrain, etc... ?

[earok]

@pixie It's on the OCS Amiga, should be fine on A500 other than a frame skip when the map loops around. It might be possible to use copper trickery to extend the detail.



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Latest experimental:

Amiga improvements:

- Fixed bug reported by @Azatotb where the parallax import wouldn't always display an error about which lines have too many colors (I believe this has been a long standing issue, that may have been reported before, but I hadn't really dug too deeply into it until now).

Mega Drive improvements:

- Fixed bug reported by @DomKid where full screen panels wouldn't properly be unloaded (and thus gameplay wasn't actually possible).
- Fixed bug where scroll routine would attempt to draw out of bound tiles (crashing BlastEm!)
- General tidy ups relating to panel rendering.

Universal improvements:

- Some minor tidyups related to serialisation of data files.

[captain]

@earok, i have a question regarding Scorpion Engine. I'm working on a game, and would like to make the computer controlled actors react to either events or blocks. I want the computer controlled actor (enemy) to be destroyed when touching a certain tile/block/event. As long as the actor is a player, it works fine, but with CPU controlled actor, I've had no luck. The CPU actor simply doesn't react to blocks or events. Hope you can help!

[captain]

@earok, I managed to make tit work by changing the CPU actor type to Projectile. Not really ideal, but it works

[earok]

Originally Posted by captain

@earok, I managed to make tit work by changing the CPU actor type to Projectile. Not really ideal, but it works

Apologies for the slow response!

That is the solution - projectile is maybe not the perfect name, but in Scorpion it essentially means "special type of actor that can collide with other actors and blocks". Collision detection can be relatively slow which is why actors, by default, don't do it against other actors or blocks.

They have been used for things that aren't literally projectiles (UltraNarwhall came up with the idea of flagging regular enemies as Projectiles so that they could collide with invisible blocks that tell them to turn around)

[captain]

Earok, thanks for your answer! The idea of making enemies turn around with blocks is definately something I'll look into. And btw, thanks for making all of this possible, Scorpion Engine is a fantastic tool breeding new life into our Amigas

[earok]

Thanks @Captain, I really appreciate the kind words!

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I attempted to make an Arkanoid clone in Scorpion live on Twitch. Thanks to ClassicGamer76 for the art.

Part 1 wasn't perfect (a little too ambitious for a short stream I think, also being live meant that I wasn't able to think too deeply about solving complicated issues), but Part 2 will come sometime and should solve the problems that were left unfinished.

[ Show youtube player ]

[earok]

Latest experimental check in:


Amiga improvements:

- Fixed bug to do with rendering the Bar element
- Space bar can be used to dismiss static panels (same as Fire button)
- The "Pause" default codeblock upgraded to support the CD32 Play button
- Commands using CD32 buttons were broken, they should work as expected now


Mega Drive improvements:

- Rendering is changed a bit so that blocks are on the foreground layer and tiles are on the background layer - meaning that there's no longer "black" in the blank area of a block.
- Various fixes for panels. In general they should be a little less glitchy and less likely to have "transparent" areas that show the area underneath.
- Added the ability to cancel a sound effect (note - this may be reworked to be able to cancel audio on MDSDRV priorities 0-3 individually rather than just on priority 0, which all MD sounds are currently played through).


Universal improvements:

- Fixed some bugs that popped up on the Arkanoid stream to do with setting an angle when setting speed.
- Merged "Camera Position / Camera Position Center" commands (a tickbox determines whether the offset is from the center or the top left).
- Animation directions are intelligently autofilled - no need to manually set all directions.
- Animation directions can be individually turned off, eg in a Zelda-like game you may want it so the player character has no diagonal animations (previously you'd leave a direction as blank to do this, you now just need to untick the Enable Direction box for the direction. This also removes the direction from the list of animations). Some movement types have these turned off automatically, eg there's no diagonal directions for CPU path.

[earok]

Latest experimental update:

Mega Drive improvements:

- Major improvements for audio, in particular MML files can be flagged as music, and loaded via the Play Music command. There's still a few things I need to fix so far as pausing/resuming, volume etc is concerned. Also note that the "scale" of volume may be quite different between platforms, so you may need to write specific code for Amiga and Mega Drive for cross platform projects.
- Compiler improvement for smaller cartridges, the "base" project patterns are kept separate from the level patterns.
- Tidy up on map tab, all Amiga specific functions are hidden.


Universal improvements:

- Volume is out of 256 (rather than 64). On Amiga at least, it still rounds to 64, but on other platforms there may be a larger number of distinct volume levels (Mega Drive has 128 for example, future platforms like Neo Geo or Jaguar may support more).
- Fixed bug where loading music at the same time as a full screen panel wouldn't actually trigger the music.
- Ability to enable or disable a layer of tiles for individual platforms (eg, if you wanted to have an additional layer of detail tiles for AGA that isn't enabled for OCS, or maybe some objects that's only on Mega Drive or Amiga, you can do that). When you open a map in tiled, and select a layer, you should see the name of the currently selected platform on the left, and be able to untick from there.
- Panel drop downs only display the relevant panels (eg, if your command is to select a bottom panel, it'll only show the list of bottom panels).

[captain]

@earok, I have another question. I noticed, that an actor can be slightly off the screen without going 'offscreen'. I would like to know if there is any way to increase this value, so that the actor has to be even further away from the player before 'going offscreen'? The easy solution is of course setting the actor to 'never recycle' but i'd prefer a more economic solution :-) Hope you can help!

[acidbottle]

the buffer value on the main project tab I think.

[captain]

@acidbottle, thanks, I tried it now but unfortunately that did not change anything...

[earok]

Originally Posted by captain

@earok, I have another question. I noticed, that an actor can be slightly off the screen without going 'offscreen'. I would like to know if there is any way to increase this value, so that the actor has to be even further away from the player before 'going offscreen'? The easy solution is of course setting the actor to 'never recycle' but i'd prefer a more economic solution :-) Hope you can help!

Apologies, I missed this message - try something like decreasing the SpawnArea_X by 16 and increasing the SpawnArea_Width by 32 (or double or triple those values). (This will mean that actors will be spawned slightly further outside the screen, but it should also mean that actors can move further from the center of the screen without recycling).

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Latest experimental:

Amiga improvements:

- Resolved bug where a keyboard command could be triggered multiple times in a row, if the keyboard command also loaded a level or a panel.


Mega Drive improvements:

- Parallax! It's implemented very differently to the Amiga side, though I do want to implement something like it in future for Amiga for dual playfield (and to replace the AGA parallax used in Gothicvania). Basically you'd create a new panel with the slot set to "Mega Drive Parallax", set the scrolling speed, and then assign that panel to the map in the map tab. Not well tested, but sizes up to 512x256 should be okay.

This is one of the last major milestones left before Mega Drive will be a viable platform for development in Scorpion.


Universal improvements:

- Resolved bugs relating to the loading of top or bottom panels.

[captain]

@earok, again thanks for your help, the SpawnArea_Width did the trick!

[earok]

Thanks @captain, glad it worked!

Looking forward to seeing what you're working on.

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Latest experimental:

Amiga improvements:

- Bug reported by Lemming880, invisible blocks weren't honoring the OnAnimFrame setting.
- Added ability to change the color in a parallax background, provided that it's only a single color through the entire parallax image (you can't change a color in a gradient - yet). The Bullet Hell demo has been updated to include blinking red lights as an example. A side effect of this is the copper is slightly more lightweight, and if there's no gradient, the parallax should fade in with everything else.
- Largest mod file is listed in the build log. If you really want to squeeze out some chip ram, looking at the single largest mod file would be a good place to start (trimming down the second largest won't save any memory since Scorpion only allocates enough memory to contain the largest mod.)
- Sounds that are (likely) unused are listed in the build log.
- New render mode - "Shadow". Basically the opposite of highlight as it uses the bottom color on the palette rather than the top color (usually black). Depending on your parallax setup, this may make actors appear to be invisible or "part of the background", or cut through the tileset to the parallax behind.


Mega Drive improvements:

- Added support for "priorities" (also known as "request slots"), which allow for multiple sounds to be played back simultaneously. Priorities 0-2 are for SFX (3 is reserved for music). For example - if you have a sound on channel F (PCM1) as priority 0, and a sound on channel K (PCM2) as priority 1, those two sounds will "mix" rather than one cancelling the other. If you have two sounds on the same channel, the one with the lower priority number will be played (which is to say, SFX using the same channel as background music will always override the background music).
- Also added the ability to cancel sound on any "priority".
- Control Events (for being able to trigger code blocks from button combinations) have been added.

[earok]

The latest experimental update brings another major milestone needed for Mega Drive development.

All animations can now be "streamed", and are streamed by default (this can still be individually disabled to squeeze a little more performance out). What this essentially means is that sprite patterns are loaded from the cartridge to the video memory at real time, allowing there to be vastly more than 64KB of sprite animations.

Before today, most Scorpion games couldn't be ported to Mega Drive, now at least in theory it will be possible for nearly all of them.

This was the last major milestone that needed to be crossed before I felt confident enough to declare that - the experimental Scorpion Engine now officially supports Mega Drive and Genesis development, albeit in an "early access" state with bugs and inefficiencies. I believe it is the first such "game creation engine" to exist for Mega Drive, and almost certainly the first that also supports Amiga development.

I'll be going on stream later, maybe about 3-4 hours - https://twitch.tv/earok - to do a bunch of Mega Drive tests and development, see how many of my projects I can get to run to some degree on Mega Drive, make a few notes of things I need to add/fix and so on.

[UltraNarwhal]

Very impressive Mega Drive development

Did notice something on real MD hardware (not on emulators).Scorpion splash screen rolls in 60hz (not 50hz) due to being more than 224 lines high.

Tested by making a 240 high panel display in-game, resized panel to 224 high and works fine at 60hz