https://github.com/luomu/bulletml
BML plugin for Construct
https://github.com/luomu/bulletml
Last synced: about 2 months ago
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BML plugin for Construct
- Host: GitHub
- URL: https://github.com/luomu/bulletml
- Owner: Luomu
- Created: 2010-05-26T18:38:06.000Z (about 15 years ago)
- Default Branch: master
- Last Pushed: 2010-08-17T19:03:33.000Z (almost 15 years ago)
- Last Synced: 2025-03-26T10:36:26.778Z (2 months ago)
- Language: C
- Homepage:
- Size: 273 KB
- Stars: 6
- Watchers: 1
- Forks: 0
- Open Issues: 2
-
Metadata Files:
- Readme: README
Awesome Lists containing this project
README
BulletML Construct plugin -- Release 1.02
Download plugin:
http://paahdin.com/projects/bulletml/BulletML-1.02.zip
Source code:
http://github.com/Luomu/BulletML
Demo game:
http://paahdin.com/projects/bulletml/demo
* What is BulletML?
Bullet Markup Language is an XML-based system for describing bullet
barrages in shoot 'em up games. It is designed by the prolific
shooting game author Kenta Cho.
http://www.asahi-net.or.jp/~cs8k-cyu/index_e.html
The BulletML page can be found at
http://www.asahi-net.or.jp/~cs8k-cyu/bulletml/index_e.html.
Here's an example:
90
This script fires one bullet at angle 90, default speed. Not terribly
useful yet. Here's a more complex example:
0
150
100
$rand * 360
200 + $rank * 200
50
This script fires a slow-moving bullet that in turn spawns 100 other
bullets at 50ms intervals, in random directions. The speed of these
bullets depends on the difficulty level (rank).
Check the demo game for a variety of patterns.
* About this plugin
This plugins adds a BulletML object that can read and play BulletML
files. It is a bit like the existing particle system object; you can
have multiple emitters and each object manages its own bullets.
While any bullet pattern could be created with events, describing them
with external files is more reusable and they can be modified without
changing the .cap.
* Appearance
You can either let the emitter render the bullets (just like a particle
system) by setting a texture or you can replace the bullets with
Sprite objects.
* Collisions
If you are not using Sprites as bullets this object has its own collision
condition. All collisions are bullet point against object bounding box.
Arcade shoot 'em up games usually use hidden hitboxes that are smaller
than the player craft.
Bullets are destroyed when they collide with an object.
* Directions, targeting
(absolute directions) When script type is "vertical" 0 is right and 90
down. With "horizontal" 0 is up and 90 right.
If you want the bullets to fly in the direction the emitter is
pointing, use "relative" direction and angle 0.
When no direction is specified, BulletML spec assumes "aim" is assumed;
bullet flies to the x,y coordinate set by "Set target position" action.
* Lifetime
Bullets are destroyed when they collide, exit the screen (toggleable),
their associated Sprite is destroyed or a set number of milliseconds is
exceeded.
If you Destroy the emitter, all its associated bullets vanish. This is a
technical limitation, but not too tricky to work around.
* Units
Speeds are pixels per second, time units are milliseconds. The BML spec
treats time values as frames for some reason but this wouldn't be very
useful when frame rate can be anything from tens to hundreds.
Separate multiplier values are provided for speeds and time values.
* Learning BulletML
Reading just the reference is not very good for learning the capabilities
of this system. Check out the demo game, this Java-based demo applet
http://www.asahi-net.or.jp/~cs8k-cyu/bulletml/bulletml_applet_e.html or
download some of Kenta Cho's games - many of them contain BulletML files
you can take apart.