Ludum Dare 31 — December 5th-8th, 2014 — Theme: Entire Game on One Screen

Back to Browse Entries

Behind The Screen - Thanks Ralph Baer

by psychopsam - Jam Entry

[EDIT Final jam entry update to fix a bug with the player score 2 being detected which now works leading you to the first vertical blank period- however not much of a game - will finish game and link here as Post Jam game so you can play the final intended version if I had more time - you can keep the game going however if you want to try by redrawing the bats so the ball stays in play just for fun. Later this will count.]

Here’s my jam entry so far. It’s called “Behind The Screen” and is in tribute to the late Ralph Baer (“Father of Video Games”). You get requests from the game such as “Draw Player1″ or “Add 1 to Player 1 Score” down the bottom of the screen at the DOS prompt – you need to react to it – do what you are requested to do.
This all happens between a refresh of the raster beam – using the timer at the top. The unseen players the other side of the screen are trying to play Pong and you are the computer. You have a pixel budget which diminishes over time. You need to draw pixels to make the paddles (or redraw the score) and then when a request such as “Move Player 1 Up” comes up in the DOS prompt, you spend your pixels on adding one to the top and removing one from the bottom of a paddle.
When the VSync happens the player is none the wiser and it looks like their paddle moves up the screen. At the refresh of the screen the ball moves one pixel. If you start stuffing up i.e dont draw the paddle in time or don’t update the score the player’s pain increases until they rage quit because of the “stupid game!!!!”.
To aide you is PixelMan who races around the screen turning pixels on and off for you. Not sure this is actually fun to play right now, but only time will tell.

What you can do.

1. Draw player bat 1

2. Draw player bat 2

3. Draw the score 1

4. Draw the score 2.

5. Ball will bounce - just finding that bug now. (DONE)

TODO (post jam)

5. Detect edge of screen and update scores - so tell player to redraw scores.

6. End game when a screen player reaches 10

7. End game when (you) the actual player stuffs up too many times and annoys the other players.

Downloads and Links




TriSquare says ...
Dec 9, 2014 @ 2:20am

Your Game is very Cool :) The Green hurts my eyes though.

psychopsam says ...
Dec 9, 2014 @ 3:07am

Thanks. Please try it again since I fixed the bounce bug.

panda says ...
Dec 9, 2014 @ 3:13am

Awesome idea, fits the theme perfectly! It's too bad that the game stops after we've drawn 0-0, since the score doesn't change.

psychopsam says ...
Dec 9, 2014 @ 3:15am

thanks panda - yep just ran out of time. I'll finish it though and post a link up as a final (not for judging though) After that I'll change the game to Space Invaders - yes! Draw each spacer invader - one.... at.... a.. time!!!!

GrabenGroup says ...
Dec 10, 2014 @ 11:48am

very cool concept!!! but needs a little bit more work i think...

jhice says ...
Dec 10, 2014 @ 11:52am

4 stars for innovation and theme ;) Request for score not appeared when "ball" went out of the screen ?

psychopsam says ...
Dec 10, 2014 @ 5:33pm

thanks guys - yep it needs those extra features but i ran out of time. I will put up a non-judgable build in the next couple of days to add the completed feature set.

RadStar says ...
Dec 11, 2014 @ 9:49am

original gameplay, but the goal behind the game is not really clear...

Dec 11, 2014 @ 11:38pm

nice one :þ

srakowski says ...
Dec 11, 2014 @ 11:48pm

I love the aesthetic! The idea is really good and fits so elegantly with the theme. Well done!

OFF says ...
Dec 12, 2014 @ 11:34am

The main idea is really nuts but amazing, the main issue is that it's actually quickly repetitive. The idea would be really fun with a plateformer for exemple and sprite instead of pixel.
The game is also badly explain, i had to look to a screenshot to understand where draw the player but whe it's became clear the game became almost strategic.
Nice idea, and good execution.

MintArcade says ...
Dec 12, 2014 @ 9:47pm

Awesome. This is great game. Theme implementation and the use of "original green" - what win for me.

Shampop says ...
Dec 14, 2014 @ 7:12pm

Idea is fun. Just a little incomplete, i think. And you should maybe put some goal. But i had fun !

Kabukky says ...
Dec 25, 2014 @ 5:56am

Great use of the theme and great esthetics!
As others have said, there is a need for more features - but you can't really complain about that looking at the time restrictions of LD.

Dec 28, 2014 @ 11:11pm

This is an interesting baseline for something, but right now it doesn't quite feel like a game yet. I like the glowy greenscreen effect though.

You must sign in to comment.

TEAMS: Teams entering the Jam should pick a single representative to submit your game, or create a team specific account you can share. We currently do not support Team Voting, but sharing an account and together playing and rating games is acceptable.

NOT LOGGED IN?: If you get a message about not being logged in, even though you are, it’s because your web browser cached the non-logged in page. You can fix this by either refreshing your cache or clearing your cache. CTRL+F5 in many browsers. Chrome is a bit more work. Press F12 to enable Developer Mode, then you can right click on the refresh button and select “Empty Cache and Hard Reload”. This option is unavailable if you are not in Developer Mode.

PORTS: Ports to other platforms can be done after the deadline. That said, the sooner you finish your port, the sooner people can play your game, improving your chances of placing in the final results. For best results, provide a Web version of your game, or a Windows version with no dependencies. Also be sure to rate about 20 games to improve your visibility.

MY GAME DOESN’T SHOW UP: If you can’t find your game, it’s usually because the URL to your downloads are missing ‘http://‘. Fix your URLs ( and you will show up. Alternatively, if you just posted it, wait a minute. The cache may not have refreshed yet.

MY GAME CRASHES, IS UNBEATABLE, OR I MADE A TYPO: We allow you to fix crash or win condition bugs after the deadline (in a sense, like “porting” to support more players). We also allow “typo” bugs. I.e. A true that should have been a false, a word that should have been a different word, very tiny changes that you would have caught if you had more sleep. We leave this open to interpretation, but generally speaking your game should be identical to the game you submitted. No new features, just things you messed up last minute. Typos.

[cache: storing page]