atari2600land's Blog

I misread the title on this topic as D(Z) Jay and thought you had begun a fan game about him.

Hey! That's me jumping on the platform!!!

Chris, why do you say it's not simple to add random platforms appear at different Y positions?

 

As I remember the original Doodle Jump game, the platform placement was not random, but an actual level map. For a vintage console, it may be easier to randomly place them, since creating a large map may take too much memory. So here's how I would do it:

• Have a timer ticking every few frames
• On every tick decide whether you should place a platform or not. Maybe a 20% chance or something low like that.
• Select a random length from "short," "medium," "long"
• Select a random position on the X axis
• Draw a new platform of the selected length at the selected X position on the top row of the screen
• On every tick, move the platform down one row on the Y axis.
• If the platform reached the bottom, clear it.
• Do this for every platform you can create simultaneously.

 

You then detect collisions only when the jumper is on its downward trajectory.

 

The original is a bit more subtle, but something like that will do for an vintage retro console.

 

It doesn't seem like a big problem, although I must admit I do not know the limitations of the Oddessy2.

 

Good luck!

-dZ.

Does the Odyssey^2 have a frame buffer similar to e.g. the Intellivision, or is it based on raster beam graphics like e.g. the Atari 2600? I would imagine generating random values for X and Y not being too hard, but perhaps placing the platforms at those random positions would be more troublesome depending on how the graphics are generated and displayed.

What I meant by placing Y values for the platforms was having them scroll continuously down. I tried to do this for a few hours but ended in failure. So I have a new idea for the game: Delete the platform you just jumped on and place it elsewhere on the screen. I can do Y values with this easily. Although I had trouble with X because the random number generator on the Odyssey 2 doesn't work very well. But I found a workaround.

But... Isn't "scrolling" the platforms continuously down the same as erasing them and drawing them below? Except that the Y coordinate is incremental (decremental?) instead of random.