Bouncing ball within a bouncing frame

[MarkTheStrange]

This was a challenge on the Facebook C64/C128 programmers group:

Create a sprite with a frame. Bounce a pixel within the sprite's frame. Bounce the sprite on the screen.

I thought an X16 version would be a fun task. The challenge was specifically to do it entirely in BASIC on the C64 using an expanded sprite (double-width, double-height) in a program with the smallest memory footprint (my X16 version takes up 244 bytes, but you get to stare at a screen doing nothing for many seconds while it initializes the sprite bitmap dynamically).

Since a square sprite makes for a boring bounce along a line between opposite corners, I made the ball bounce within a 48x42 rectangle inside the 64x64 sprite (to match an expanded sprite on the C64).

Screenshot 2025-02-19 at 17.14.51.png (69.17 KiB) Viewed 933 times

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[ahenry3068]

This was a challenge on the Facebook C64/C128 programmers group:

Create a sprite with a frame. Bounce a pixel within the sprite's frame. Bounce the sprite on the screen.

I thought an X16 version would be a fun task. The challenge was specifically to do it entirely in BASIC on the C64 using an expanded sprite (double-width, double-height) in a program with the smallest memory footprint (my X16 version takes up 244 bytes, but you get to stare at a screen doing nothing for many seconds while it initializes the sprite bitmap dynamically).

Since a square sprite makes for a boring bounce along a line between opposite corners, I made the ball bounce within a 48x42 rectangle inside the 64x64 sprite (to match an expanded sprite on the C64). Screenshot 2025-02-19 at 17.14.51.png

Try It Now!

Had to do my Own version . I DID NOT even look at Mark's code.

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[MarkTheStrange]

Had to do my Own version .
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Well, that's much fancier. Change the frame to a gilded picture frame and it will fit right in.

[ahenry3068]

Had to do my Own version .
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Well, that's much fancier. Change the frame to a gilded picture frame and it will fit right in.

That's doable... I will see.

[kelli217]

Looks like Robin saw the challenge too. [yt]https://www.youtube.com/watch?v=zwTA7xi0QD0[/yt]

[ahenry3068]

Added some interaction between the ball & the box.

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[desertfish]

There's some weird physics going on with the ball though. It changes course sometimes even when it is not actually touching the sides of the box.

[ahenry3068]

There's some weird physics going on with the ball though. It changes course sometimes even when it is not actually touching the sides of the box.

Well this is Not real physics
But REAL PHYSICS would eventually stop the animation with friction !!!!

I thinks this looks a bit more Realistic to the Eye.

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