jetpac.nes/src/enemies.s, branch main

Add sound effects

2026-04-13T14:34:11Z

Signed-off-by: Miquel Sabaté Solà

Try to initialize enemies on unique Y coordinates

2026-03-22T14:17:24Z

That is, our PRNG algorithm is so stupid that sometimes it cycles into the same value multiple times. While play testing, sometimes we were so unlucky that we got all enemies on the same Y screen coordinate. As funny as these situations can be, this shouldn't happen, so I have introduced an (awesomely named) function that makes a harder effort at finding a unique random number. Signed-off-by: Miquel Sabaté Solà

Rename init_x() to init_enemy_x()

2026-03-11T22:41:08Z

This is just a minor fix for an overstep from commit 270d60d58d3e ("Rename scoped variables without being redundant"). Signed-off-by: Miquel Sabaté Solà

Apply a correction on enemy movement for PAL

2026-03-11T22:36:48Z

We cannot just "inc"/"dec" for enemy movement, but we have to apply an overstep on PAL every 5 frames in order to be equivalent to the NTSC version. This has been abstracted away on a macro that just does "inc"/"dec" on NTSC, but does this proper "adc"/"sbc" instructions with a helper memory region which is updated every 5 frames. Signed-off-by: Miquel Sabaté Solà

Move some variables into another memory region

2026-03-06T23:44:28Z

The zp_player_tile_* variables fit perfectly with the space that is left in the $0x memory region. This allows for a more contiguous space (e.g. on $Cx) for other elements to come (e.g. items). Signed-off-by: Miquel Sabaté Solà

Ramp up the revive counter for enemies

2026-03-06T23:08:05Z

This way it feels more like a swarm of enemies and you don't have any resting time. Signed-off-by: Miquel Sabaté Solà

Fix documentation error on the 'chase' algorithm

2026-03-06T23:04:37Z

Signed-off-by: Miquel Sabaté Solà

Bump up to 4 enemies per screen

2026-03-06T22:51:57Z

This is more similar to the original game, and it's a bit more fun. In order to do so some variables had to move into another memory page, but that's fine as we have plenty. Signed-off-by: Miquel Sabaté Solà

Make more things operate on SIZEOF_POOL_ITEM

2026-03-06T22:43:26Z

Out of consistency, let's use it, and this way experimenting with the amount of enemies per screen won't be as painful. Signed-off-by: Miquel Sabaté Solà

Convert enemy vs bullet collision into a loop

2026-03-06T22:40:02Z

The fact that unrolling the loop was easier or faster was a plain lie from my lazyness. Convert it into a proper loop just so we can experiment with adding more enemies in one screen. Signed-off-by: Miquel Sabaté Solà