Emerald Dash levelsets in the Emerald Mine Club collection not properly playable

[Ryz]

Heya folks,

I recently got back in the kick of Boulder Dash-like games as of late, and one of things that I wanted to bring up is the Emerald Dash levelsets unable to be played normally in Rocks'n'Diamonds through the the Emerald Mine engine. I wasn't sure if this should be under the 'Bug Reports' section, but I feel it's needed since the engine lacks the specific things needed for the Emerald Dash levelsets to play properly, which is what if Emerald Mine has the properties of the Boulder Dash game object logic? Gems being able to harm enemies, amoeba turning into gems if trapped, amoeba turning into rocks if it grew too much, and those special dummy players that if got harmed would also apply to the actual player. Since the Boulder Dash engine has been released, why not address this?

If you go to this link on the search query of 'Emerald Dash' for the YouTube channel, petsasjim1, you'll find some recordings of how they are played, which looks really fascinating.

Some examples of YouTube videos, timestamped:

• https://youtu.be/kYtO1eNyLbc?t=69 - Gems hurting the butterflies, 9 gems that are worth 1 point from that butterfly explosion and no gem worth 3 points, and amoeba being turned into gems...even though they can grow into dirt. This is while playing Emerald Dash 14, level 80.
• https://youtu.be/5IvDQmuo28g?t=51 - Unusual amoeba behavior, seeing the gem dropped into the magic wall makes all the amoeba tiles into gems? This occurs on Emerald Dash 11, level 00.
• https://youtu.be/QL78ckC_2gQ?t=321 - No such thing as Amoeba Drops since it's a Emerald Mine-specific feature, no, this is a Boulder Dash-style Amoeba growth. This happens on Emerald Dash 12, level 03.
• https://youtu.be/QL78ckC_2gQ?t=398 - Amoeba growing too much and all of them becoming boulders instead of gems. This also occurs on Emerald Dash, level 03.
• https://youtu.be/iZ3suOHsktA?t=107 - Dummy player sightings! Couldn't seem to find the dummy players being harmed at the moment. This instance is sighted on Emerald Dash 5, level 00.

The curious thing if this is addressed is how would this be implemented in terms of detecting those particular levelsets that play differently from regular Emerald Mine levelsets? Like a sub-engine within the Emerald Mine engine, as an option in the level editor?

EDIT: Edited the post to include the levelset and level name in each of the listed bulletpoints in the event the YouTube videos might have vanished.

[ncrecc]

for what it's worth this is also an issue on emeraldmines.net, which uses the same EM engine as RnD: http://emeraldmines.net/play/src/dev.html?disk=99/14

[Holger]

Hi RAP, nice to hear from you again!

And with a great topic! I always wondered about the title screens of the Emerad Dash series:

emerald_dash_1_title.gif (14.06 KiB) Viewed 2333 times

All things it describes are not supported by the "normal" EM/EMC game engine used by the many EMC disks (or ADFs, when playing in an Amiga emulator), so apparently it is an "exclusive" version of the standard EM/EMC game engine with C64 Boulder Dash modifications. Indeed, this is all not supported by the EM engine in R'n'D.

But I think it could easily be! You have already listed the main differences very well, and playing the original ADFs in emulation should make it fairly easy to check those differences.

The curious thing if this is addressed is how would this be implemented in terms of detecting those particular levelsets that play differently from regular Emerald Mine levelsets? Like a sub-engine within the Emerald Mine engine, as an option in the level editor?

When creating new R'n'D levels using the EM engine, this could indeed be made configurable by a new checkbox to enable those special engine modifications. For existing, old EMC level sets (as part of the EMC collection for R'n'D, which are converted from the original ADF files), the original, native EM/EMC level file format is used. To automatically use those EM engine modifications for BD behavior, I would either have to look for some differences in the level format that indicate that a modified engine has to be used, or add an explicit flag to the "levelinfo.conf" file for all affected level sets (which will only enable the changes when playing with a new game engine version, so existing tapes for thiose level sets (for those levels which are solvable even with vanilla EM/EMC behavior) would still work).

for what it's worth this is also an issue on emeraldmines.net, which uses the same EM engine as RnD: http://emeraldmines.net/play/src/dev.html?disk=99/14

That's true. And -- at least for me -- the browser based version of the engine seems to run with double speed, which makes all those levels quite hard to play.

[Holger]

P.S.: Especially the "dummy player" behavior (if killed, player gets killed, too) seems to be interesting -- the game element used for this seems to be the "spring bumper", so finding Emerald Dash levels that may use this game element with different properties might be easy by checking all those levels in the R'n'D level editor for this specific game element...

[Ryz]

Watching more of the YouTube videos, there's some interesting instances of using elements from Emerald Mine within the Emerald Dash levelsets, some within the levels themselves, but most from level 00:

• https://youtu.be/XN9o5PtKxSs?t=605 - Emerald Dash 16, level 01: Acid pool and the associated acid pool tub walls, I wonder if it was in the original levelsets before it got converted, or was there like an acid element in a custom engine or version of Boulder Dash?
• https://youtu.be/9gvkOcxZ5VA?t=162 - Emerald Dash 28, level 00: Keys and doors? That's definitely more Emerald Mine than Boulder Dash stuff!
• https://youtu.be/9gvkOcxZ5VA?t=185 - Emerald Dash 28, level 00: Wha? Magic balls? Using the player character art as the magic ball to spawn those Spaceship-equivalent enemies?
• https://youtu.be/9gvkOcxZ5VA?t=193 - Emerald Dash 28, level 00: Yam yams as well? They 've not been being smashed yet, but the iconic movement is still retained!
• https://youtu.be/9gvkOcxZ5VA?t=202 - Emerald Dash 28, level 00: Even dynamite? Again, Hasn't been used yet, but they're collectible!
• https://youtu.be/pjrPCTKZAao?t=265 - Emerald Dash 31, level 00: Balloons and even the wind direction tile?

Like, really interesting, especially since it's like at the latter half of the whole collection of Emerald Dash, which, I'm surprised there isn't any more Emerald Mine and Boulder Dash levelset hybrids, and the thing is, these Emerald Dash levelsets were the last of the collection in the Emerald Mine Club before things slowed to a trickle and stopped, which again, makes me wonder where all those people involved in the scene nowadays, notably since the organization and the website has long since been gone.

And more sightings of Boulder Dash functionality, beyond the visuals:

• https://youtu.be/XN9o5PtKxSs?t=665 - Emerald Dash 16, level 01: Magic wall changes between boulders and gems, not sequentially like boulder to emerald to diamond and then back to boulder like how it was handled in Emerald Mine.
• https://youtu.be/9gvkOcxZ5VA?t=518 - Emerald Dash 28, level 03: A more clearer instance of the dummy player in action, with the player accidentally revealing the path towards it for the Bug-equivalent enemy to go into it, causing level loss, with the player exploding in a unique explosion radius.
• https://youtu.be/NQqBDvGaVlo?t=309 - Emerald Dash 22, level 01: Curiously, the bugs still retain the chain explosions from Emerald Mine, which definitely wasn't a thing in Boulder Dash.
• https://youtu.be/mmGvA6w0mKo?t=171 - Emerald Dash 04, level 00: Oh, I guess the dummy players don't really die from rocks falling down onto them, or are these magic balls in disguise?
• https://youtu.be/ovssONrPL6s?t=114 - Emerald Dash 20, level 80: Quicksand? Or are these like the slime one from the second Boulder Dash game but it's blue and not green like the amoeba? I think those were randomized whether the rocks fall through, this acts more like Emerald Mine's take of it.

I edited my main post to include the levelset and level number in case the YouTube videos in the unlikely event would've vanished.

Yeah, it would be really neat if these particular set of levelsets would be properly playable, and which again, it would be wild to mix the two stuff together and make a brand new levelset out from this and not relegate it to being Boulder Dash conversion levelsets. This would've been more difficult to document if it weren't for the snapshot videos from that YouTube channel.

[Holger]

I think I have added all required differences for playing the many "Emerald Dash" level sets to the native Emerald Mine game engine now, just as you have described them (only the screen flashing when the amoeba turns to diamonds is not implemented yet, and I think it would be better to use this effect to indicate that the exit door is open, just like Boulder Dash did it).

All these changes will be available with the next R'n'D version, hopefully soon (but it may also be possible that it will still take some time, as I am just in the middle of some improvements for playing Diamond Caves levels).

Thanks a lot for taking the time to describe all these changes, and link to videos that demonstrate them -- this was really very helpful!

If you should find some more changes, please let me know! (For example, I wonder what happens if the "voodoo player" will meet other enemies like yam yams or robots -- currently it is only killed by bugs and tanks (space ships), as I could not find any level where both yam yams or robots and voodoo players are on the playfield.)

[Ryz]

The only thing I can think of extensive testing of the tweaked objects specifically for Emerald Dash with the original objects that were remain untouched is let's say get the final Emerald Dash levelset, which is Emerald Dash 35, and have a random level, like level 0, and modify that level in some way, and try to play it on the Amiga. Additionally, the modified engine should be the exact same from the first to thirty-five, right?

As I looked at this forum topic, I decided to poke the Emerald Dash levelsets by checking it on Rocks'n'Diamonds 4.4.1.3 that would warrant some additional pointers for increased compatibility:

• Emerald Dash 33, level 01: What is this sorcery? Wraparound? There's a gem instead of the outer border of the level, and a dirt tile also instead of a steel wall.
• Emerald Dash 29, level 58: So, II know there's wraparound left to right in Emerald Mine Club levelsets, but I'm not sure if it extends to going up and down, but if so, there's an instance that wraparound up and down is needed to solve this level properly!
• Emerald Dash 27, level 00: Wait, the springs can kill bugs in a similar manner as robots? The bugs are positioned in a way that just having the springs just being dropped on top of them wouldn't be possible. This really needs some testing!
• Emerald Dash 23, level 44: Huh? Horizontal wraparound might work a bit differently from the expected wraparound? Like it goes the same lining instead of having to wraparound by one tile off?

...And some observations (which may or may not point towards having to do some increased compatibility):

• Emerald Dash 22, level 00: What? It's possible for a magic wheel to be initially activated without the player's input? How? I deleted the specific spinning magic wheel out of curiosity, but the robots keep going to that position. Could this be part of the editor? You already did it with the various Boulder Dash engine elements in various differing states.
• Emerald Dash 32, level 62: I hope these Spaceships would've been smashed by the gems since it's in the modified engine, because if not, trouble's a brewing.
• Emerald Dash 32, level 64: This looks more like a normal Emerald Mine level?
• Emerald Dash 29, level 26: An example of a level extending beyond the usual border limits, those amount of boulders at the top of the level. Also, bombs!
• Emerald Dash 24, level 05: Why is there a lonely tile of amoeba at the top side of the level? Is there something special about it?
• Emerald Dash 23, level 20: ...I'm not too sure what's going on here, entirely surrounded by boulders, but they would've wraparound vertically?
• Emerald Dash 04, level 00: ...It doesn't look like dummy players can die from falling boulders? Otherwise this level would be impossible to finish.

There's probably more that I might've missed, and worked backwards, as you can see from the levelset numbers decreasing, but there's a lot more weirdness than I expected from these levelsets.

[ncrecc]

• Emerald Dash 04, level 00: ...It doesn't look like dummy players can die from falling boulders? Otherwise this level would be impossible to finish.

for the record this is consistent with how dummy players work in boulder dash (they only kill the player if an enemy is adjacent to them)