Pick Axe Pete

[+johnnywc]

Hello all,

 

On recommendation from PacManPlus, I've been playing some Pick Axe Pete for the O2 and was wondering how (and if) it could be faithfully converted to the 2600. For those not familiar with the game, here is a screenshot:

 

 

Gameplay is fairly simple: You control Pete, you run left/right, climb ladders, jump and duck. Object is to get the most points by:

 

1) Jumping or ducking over rocks

2) Collecting a pick axe

3) Collecting a key

4) Smashing rocks with the pick axe

5) Exiting a level through one of the 3 doors once key is collected

 

Anyway, for a simple game there is a lot going on:

 

- asymetrical floors

- lots o' rocks

- ladders (max 1 on the screen at once)

- Pete

- pick axe

- key

- 3 spinning doors

 

A quick analysis of a screen shot shows:

 

- floors are 3 scanlines

- spaces between floors are 21 scanlines

- there are 7 floors = 7 * (3+21) = 168 scanlines needed for the game screen, leaving 32 for the score display (assuming 200 scanlines)

- all objects are 2LK resolution, but I believe move at 1LK resolution

- floor layout is dynamic (changes from screen to screen)

 

Anyway, I was thinking:

 

P0: Pete

P1: Key, Axe, Rock

M0: ladder?

M1: Rock?

PF: floors

BL: doors (alternating size to simulate spinning)

 

Objects

 

Doors

 

The doors change colors during the level; a PF color switch (if there is time) would allow the door to be a different color than the border (needing 12 cycles assuming the colors are stored in RAM - colorMaze and colorDoor). Door spinning is simulated by changing the BL width and position.

 

Ladder

 

Using an 8-pixel width missile (M0) could draw the ladder. Disadvantage is that it would be the same color as Pete (not white).

 

Pete

 

Always drawn using P0, always having priority over other objects so no flicker on main character.

 

Axe

 

Always drawn using P1.

 

Key

 

Always drawn using P1. I believe that the Key & Axe are never on the screen at the same time (the key does not appear when Pete has the axe, and the axe does not appear if the key is on the screen).

 

Rocks

 

Displayed primarily using P1, P0 if available. I would also like to try to use M1 if possible, allowing 3 rocks to be displayed in a zone without flicker. Would have to come up with at least 2 good animations of rocks spinning using M1 for this to work.

 

Kernel

 

The floors would be drawn with 4 writes to the PF registers, setting PF0 to a constant $80. This would take 32 cycles, leaving 44 to draw P0, P1 and possibly M1, although only in 2LK resolution.

 

The space between floors would need to draw P0, P1, possibly M1, the BL and M0 (no PF here). Again, all can be drawn in 2LK resolution.

 

Anyway, it seems possible and could be fun to play. Any thoughts are appreciated.

 

Thanks,

Edited October 6, 2008 by johnnywc

[+Nathan Strum]

Any recommended Odyssey 2 emulators on the Mac?

[kirin jensen]

I'm not sure the 2600 could do even a moderately faithful version of Pick Axe Pete. The reasons are many and varied, but an obvious example is the random creation of a 'hole' in the floor of the mine every time you go through a door. The accumulation of holes changes the movement of rocks considerably from level to level, especially further on the game.

 

Each rock moves independently, which again might pose specific problems for 2600. In general, I suspect that any version of Pick Axe Pete that gets made for the 2600 would have a similar look, but seriously simplified and predictable gameplay.

Edited October 7, 2008 by kirin jensen

[LS_Dracon]

Any recommended Odyssey 2 emulators on the Mac?

 

I found this :

 

http://www.bannister.org/software/o2em.htm

 

Require Mac OS X 10.4 or later.

Edited October 7, 2008 by LS_Dracon

[+johnnywc]

I'm not sure the 2600 could do even a moderately faithful version of Pick Axe Pete.

 

Thanks for the feedback. Although there is a lot going on, I'm pretty sure a decent 2600 version could be made with very little sacrifices.

 

The reasons are many and varied, but an obvious example is the random creation of a 'hole' in the floor of the mine every time you go through a door. The accumulation of holes changes the movement of rocks considerably from level to level, especially further on the game.

 

Agreed. My thought here would be a similar approach that I used in Lady Bug, storing the different floor patterns in ROM. The bulk of the work would be setting up the pointers prior to a level and logic to add a hole after each level, but I think it could be done. The movement of the rocks would be controlled by the layout of the floors.

 

Each rock moves independently, which again might pose specific problems for 2600. In general, I suspect that any version of Pick Axe Pete that gets made for the 2600 would have a similar look, but seriously simplified and predictable gameplay.

 

Hmmm... I just played a game and counted a max of 5 rocks on the screen at any one time. Certainly a lot of objects, but they could be represented in RAM using 5 bytes each (X, Y, horizontal direction, vertical direction, speed), maybe even less with some packing.

 

I'll do a quick analysis of the RAM usage and see if there's enough to maintain the state of all the objects plus the floor and doors:

 

- need to store the patterns for 6 floors. Since all floor patterns can be stored in ROM, you would only have to use 2 bytes per floor, pointing to a set of 4 PF data (PF1L, PF2L, PF2R, PF1R). Total = 12 bytes

- Pick Axe Pete: X, Y coordinates, and state variables for jumping, ducking, etc. estimate 6 bytes

- Axe or Key (both are never on the screen at once): X, Y, state, other... estimate 4 bytes

- Rocks: max 5; X, Y, H, V, state/speed estimate 5*5 = 25 bytes

- Doors: max 3; color, state (spinning, size), estimate 3*2 = 6 bytes

- Score: 2 bytes + highscore 2 bytes = 4 bytes

 

Total: 57 bytes, which leaves about 70 bytes for all of the graphic pointers, flicker management and object reuse. I'll start a proof-of-concept and see what I can come up with.

 

Thanks,

[+thegoldenband]

My grasp of the technical fine points of both systems is very limited, but I just wanted to say that this is a fine idea, and I suspect that a good version should be entirely possible. I look forward to seeing the results of your work.

 

(Another great Odyssey 2 game I'd love to see ported is Loony/Looney Balloon, though I think I'm the only one who likes it!)

[kirin jensen]

You know what the architecture of the 2600 is capable of better then I by a long shot, johnnywc - as Ladybug amply proves.

 

Still, I've rarely seen anything in terms of movement on the 2600 that approaches the later levels of Pick Axe Pete(or any level of Attack of the Time Lord, or UFO) with the exception of Gyruss.

 

Good luck.

[+johnnywc]

You know what the architecture of the 2600 is capable of better then I by a long shot, johnnywc - as Ladybug amply proves.

 

Still, I've rarely seen anything in terms of movement on the 2600 that approaches the later levels of Pick Axe Pete(or any level of Attack of the Time Lord, or UFO) with the exception of Gyruss.

 

Hmmm - I'll have to admit I'm not the best at Pick Axe Pete and can only get around 400 points. Does the max rock count exceed 5 as the levels progress?

 

Good luck.

 

Thanks - sounds like I'll need it!

[Devin]

I have never played the game myself. However, perhaps the ball can be used to render the holes in the floor. The background can be set to the red color and the ball (black in this case) can be moved at will between floors.

[+johnnywc]

I have never played the game myself. However, perhaps the ball can be used to render the holes in the floor. The background can be set to the red color and the ball (black in this case) can be moved at will between floors.

 

Hi Devin,

 

Thx for the suggestion - unfortunately using the ball won't work here as: (1) the holes can be larger than 8 pixels wide and (2) there can be multiple holes per floor. The good news is that I don't think it's going to be a huge issue; I should have time to do 4 PF writes (keep PF0 constant) and draw P0 or P1 (2LK) and M1.

 

I'm a little rusty with my 2600 programming (it's been about a year and a half) but I hope to have a working kernel soon.

 

BTW - GREAT JOB on K.O. Cruiser! Can't wait for that one to be on cart!

[RickO2]

Hmmm - I'll have to admit I'm not the best at Pick Axe Pete and can only get around 400 points. Does the max rock count exceed 5 as the levels progress?

 

It never exceeds 5. As you progress more "holes" appear in the floor and the rocks speed up and begin bouncing making it difficult to time you jump or duck under it. On the Odyssey2 you have an option of picking the floor layout to start (0-9). I'm not sure if this is possible with the Atari.

 

Pick Axe Pete is one of my Favorite O2 games.

 

Good Luck!

[kirin jensen]

Hmmm - I'll have to admit I'm not the best at Pick Axe Pete and can only get around 400 points. Does the max rock count exceed 5 as the levels progress?

 

It never exceeds 5. As you progress more "holes" appear in the floor and the rocks speed up and begin bouncing making it difficult to time you jump or duck under it. On the Odyssey2 you have an option of picking the floor layout to start (0-9). I'm not sure if this is possible with the Atari.

 

Pick Axe Pete is one of my Favorite O2 games.

 

Good Luck!

 

Yup, that's the thing. After 600 points or so, the rocks are all over the place - even though there are only five at one time. By the way there are actually two sets of rocks with different properties. The initial setup, by the way, should be no problem on the 2600: that's what the Game Select switch is for.

[+johnnywc]

Hmmm - I'll have to admit I'm not the best at Pick Axe Pete and can only get around 400 points. Does the max rock count exceed 5 as the levels progress?

 

It never exceeds 5. As you progress more "holes" appear in the floor and the rocks speed up and begin bouncing making it difficult to time you jump or duck under it. On the Odyssey2 you have an option of picking the floor layout to start (0-9). I'm not sure if this is possible with the Atari.

 

Pick Axe Pete is one of my Favorite O2 games.

 

Good Luck!

 

Thanks for the info - glad to hear a max of 5 rocks appear. I am working on a scheme that will allow more "holes" to appear in the floor as the levels progress. Also, having different starting layouts will be pretty simple as long as I have enough ROM space (which is usually not a problem with Atari games anymore).

 

 

Yup, that's the thing. After 600 points or so, the rocks are all over the place - even though there are only five at one time. By the way there are actually two sets of rocks with different properties. The initial setup, by the way, should be no problem on the 2600: that's what the Game Select switch is for.

 

I'll need to keep practicing to reach 600 - any tips? I usually stay low and wait for other pick axes to appear to get points by smashing the rocks. When things get too hectic, I'll try to catch a key as it moves to the top.

 

I have noticed the two different types of rocks - some seem to move in a more erratic pattern than the others (I notice some even move up). I should be able to model the behavior.

 

I have made some progress and hopefully will post a BIN soon.

 

Thanks for the help!

[Recycled]

This should be interesting.

 

A great game.

[newcoleco]

Based on the great review on Youtube from the king, I also have the feeling that this original game should be done for the Atari2600 fans.

[kirin jensen]

Hmmm - I'll have to admit I'm not the best at Pick Axe Pete and can only get around 400 points. Does the max rock count exceed 5 as the levels progress?

 

It never exceeds 5. As you progress more "holes" appear in the floor and the rocks speed up and begin bouncing making it difficult to time you jump or duck under it. On the Odyssey2 you have an option of picking the floor layout to start (0-9). I'm not sure if this is possible with the Atari.

 

Pick Axe Pete is one of my Favorite O2 games.

 

Good Luck!

 

Thanks for the info - glad to hear a max of 5 rocks appear. I am working on a scheme that will allow more "holes" to appear in the floor as the levels progress. Also, having different starting layouts will be pretty simple as long as I have enough ROM space (which is usually not a problem with Atari games anymore).

 

 

Yup, that's the thing. After 600 points or so, the rocks are all over the place - even though there are only five at one time. By the way there are actually two sets of rocks with different properties. The initial setup, by the way, should be no problem on the 2600: that's what the Game Select switch is for.

 

I'll need to keep practicing to reach 600 - any tips? I usually stay low and wait for other pick axes to appear to get points by smashing the rocks. When things get too hectic, I'll try to catch a key as it moves to the top.

 

I have noticed the two different types of rocks - some seem to move in a more erratic pattern than the others (I notice some even move up). I should be able to model the behavior.

 

I have made some progress and hopefully will post a BIN soon.

 

Thanks for the help!

 

The main things to remember:

 

You score the most points for grabbing a key and going through a door - 10 for the key and 20 for the door. accordingly, grabbing a key is the most point-effective tactic. This means heading for the top, usually the left side.

 

Once you have the key, you can stick around and grab a pick axe, but it's not necessary or recommended. Just do it if the opportunity presents itself.

 

Always jump towards the door once you have the key. That way, if a rock comes through you'll either spin and go through the door(rather than simply being bowled over) or jump the rock and make an extra point as you go through.

 

Keep track of how many rocks there are at any time. You''l be better prepared to move if you know whether there are five rocks on the screen and where they are. Be ready for the next collision.

 

Improvise. You're never dead until you're dead. Half the fun of this game is surviving nearly impossible situations.

 

Learn to duck as well as jump. It will save you many times over.

 

Watch for patterns in the rocks' movement you can exploit as the holes appear. Some will make it a great deal easier to predict where collisions will occur.

 

Waiting judiciously works better than running to grab a key or an axe. Let it come near you and avoid the rocks in the meantime.

 

On the top floor(left hand side), once you have the key jump the next rock to come out the door(and again after it hits the wall), then follow it to the door - jumping at the last moment. The rock will collide with any rocks coming toward you clearing your path and possibly giving you a new axe in the process.

 

I usually get between 800-1000, occasionally scoring in the 1700-1800 territory, so I hope this advice yields you similar results.

 

Remember: Playing Pick Axe Pete means never having to hit the Reset button

[+Nathan Strum]

For the life of me, I can't get this to work in O2EM on OS X. I can load the cart, choose a game and start it, but the controls don't respond (although the keyboard does, since I can change the letters at the bottom of the screen). Pete just stands there and dies. I've configured Emulator Enhancer to use the Stelladaptor for joystick input, and still nothing. Any suggestions?

Edited October 22, 2008 by Nathan Strum

[kirin jensen]

For the life of me, I can't get this to work in O2EM on OS X. I can load the cart, choose a game and start it, but the controls don't respond (although the keyboard does, since I can change the letters at the bottom of the screen). Pete just stands there and dies. I've configured Emulator Enhancer to use the Stelladaptor for joystick input, and still nothing. Any suggestions?

Stupid question time: are you using the right or left joystick? Pick Axe Pete usess the left on an actual O2.

[+thegoldenband]

For the life of me, I can't get this to work in O2EM on OS X. I can load the cart, choose a game and start it, but the controls don't respond (although the keyboard does, since I can change the letters at the bottom of the screen). Pete just stands there and dies. I've configured Emulator Enhancer to use the Stelladaptor for joystick input, and still nothing. Any suggestions?

Stupid question time: are you using the right or left joystick? Pick Axe Pete usess the left on an actual O2.

 

I had the exact same problem, with the exact same cure: "Swap Joysticks" in the "Emulator" menu. Don't feel too foolish, though; something about the Mac port of O2EM is less than user-friendly -- for one, there's no keyboard config panel, or none that I can find, at least.

Edited October 22, 2008 by thegoldenband

[+Nathan Strum]

I had the exact same problem, with the exact same cure: "Swap Joysticks" in the "Emulator" menu.

Thanks - that did the trick.

 

Pick Axe Pete certainly seems doable on the 2600. It'll require some flicker, but it doesn't seem out of the realm of possibility. Robert M had a good game that was pretty similar in many regards on Stella's Stocking last year: Elf Dash.

Edited October 23, 2008 by Nathan Strum

[Robert M]

I would say that a 2600 port is doable with the following assumptions.

 

1. All game objects flicker at 30 Hz.

2. Rocks colliding to form gold should instead change shape without a color change (a crystal?)

3. No more than 4 rocks are allowed per floor at a time.

4. The kernel supports skewing M0 and M1 every line pair to make pseudo sprites.

 

Object allocations.

 

Even frame

P0 = Pete

P1 = rock (recycled every floor as needed)

M0 = Axe?

M1 = rock 2

 

Odd Frames

P0 = key or spare axe

P1 = rock 3 (recycled every floor as needed)

M0 = Door (recycled on 3 floors)

M1 = rock 4

 

Ladders and floors are all PF graphics.

Edited November 2, 2008 by Robert M

[kirin jensen]

3. No more than 4 rocks are allowed per floor at a time.

 

Um. I'm guessing you played this once or twice in emulation and didn't get past the 200-300 point level.

 

By 400-600 points, enough of the mine has vanished that rocks are bouncing between floors in all sorts of patterns - each rock independently of the other. It's one of the things that makes gameplay on the later levels so exciting and unique. The rocks are all over the place by the 1000-point level.

[Robert M]

3. No more than 4 rocks are allowed per floor at a time.

 

Um. I'm guessing you played this once or twice in emulation and didn't get past the 200-300 point level.

 

By 400-600 points, enough of the mine has vanished that rocks are bouncing between floors in all sorts of patterns - each rock independently of the other. It's one of the things that makes gameplay on the later levels so exciting and unique. The rocks are all over the place by the 1000-point level.

 

So rotate the allocation of rocks to screen objects when all 5 occupy the same horizontal band. They flicker at 24 Hz. Big whoop.

[supercat]

So rotate the allocation of rocks to screen objects when all 5 occupy the same horizontal band. They flicker at 24 Hz. Big whoop.

 

Or force rocks to bounce vertically if they would otherwise enter a zone which already has four. I don't think limiting zones to four rocks should pose any particular problem, especially if rocks can occasionally have a random bounce when they reach zone boundaries anyway.

[kirin jensen]

3. No more than 4 rocks are allowed per floor at a time.

 

Um. I'm guessing you played this once or twice in emulation and didn't get past the 200-300 point level.

 

By 400-600 points, enough of the mine has vanished that rocks are bouncing between floors in all sorts of patterns - each rock independently of the other. It's one of the things that makes gameplay on the later levels so exciting and unique. The rocks are all over the place by the 1000-point level.

 

So rotate the allocation of rocks to screen objects when all 5 occupy the same horizontal band. They flicker at 24 Hz. Big whoop.

Um, yeah. BIG whoop. Take a little while and actually play through to the 500-600 point level. Never even mind the 1000 point level, where most of the mine is gone. What you're talking about is a serious misunderstanding of the play mechanics, and what you offer as a solution is a significant and serious alteration of the play mechanics.