Hi everyone — this is my first post here, so I hope this is the right category.
I make a bullet-pattern engine for RPG Maker MZ. MZ has battle systems of every
flavour, but almost nothing for real-time bullets, so I built one: a single-file,
dependency-free plugin that turns ordinary events into danmaku bosses, ranged
ARPG combat and dodge sections.
What it does
- 8 trajectory modes — spiral, sine, homing, boomerang, orbit, accelerate,
decelerate, jitter — plus a move script hook if you want your own - Bullets that actually hit events: tile match + collider overlap, with an
optional SAT collision mode. This is the part that removes the “point-blank
miss” problem you get from tile-only detection. - Hit-rate control from event-page comments: HitRate[n] / HitCondition[script] /
MissEventPageId[n] / AlwaysHitBulletName:x — Chinese equivalents work too
(命中率[n] / 命中条件[脚本] / 未命中触发事件页id[n] / 必命中弹幕名称:x) - Target filtering — by event name, by notetag, or “nearest damageable target”,
so homing bullets do not chase unkillable scenery - Thrown grenades — parabolic arc, two-stage detonation, rebounds that read the
surface they hit (walls block horizontal travel only, so a high arc clears low
walls), and arc height in tiles - RPG-style explosions — area damage, common events, animations
- 5 presets ship built in (straight, boomerang, homing, thrown, enemy bullet),
5 plugin commands (fire / fireAt / clear / toggleHitbox / listPresets)
Trying it
There is a free Lite edition on the plugin page — same engine, all 8
trajectory modes, no time limit. The only caps are 40 bullets on screen, 3
presets and 2 entries per offset group. Pro lifts the caps and adds a commercial
licence.
Installation is: drop the .js into js/plugins, enable it in the Plugin Manager,
put your bullet sprites in img/b_barrages/. The download also includes two
ready-to-run sample projects (one English, one Chinese) so you can see the
presets wired into real events.
A note on AI: the engine itself — collision, hit-rate binding, ricochet,
grenades, explosions, the preset system — is hand-written. AI was used for a
performance-optimisation pass and for drafting/translating the English
documentation. No AI-generated graphics or audio are included, and nothing is
generated at runtime.
Feedback is very welcome, especially from anyone wiring this into an existing
action battle system — target filtering and the hit-rate comments are the two
places where I would most like to hear how they behave in a real project.
Plugin page (free Lite edition): https://zhang03.itch.io/jiankes-bullet-pattern-system