roadmap.txt

Ideas of how to implement collision events and other trigger events

The ColliderComponent maintains a hit area and a list of callbacks.

During the update process, a collision manager tests for collisions between collidable objects,
namely between ColliderComponent's.

When a collision is detected, both collider components are notified by calling a method on each.

The method takes a parameter to tell the collider which object it collided with.

The collider keeps a list of these collision notifications.

After all collisions have been performed, the colliders will then call each function from its 
list of callbacks, passing themselves and the other collider.

This will implement an event/listener system to inform entities about collisions.  An entity
may simply be interested in collisions between its own collider and another, or it may be an
entity that looks at collisions between other entities.

Using this collision event system, a Trigger may be implemented which changes its state according
to whether or not the player is overlapping some hit_area.  That trigger can then alert its own
set of listeners, decoupling the events in the level from its actual source.  For example, an 
elevator may be activated by an up/down signal, and the source of that signal could be a trigger
that goes off based on a collision.  Or, the trigger may be based on a button press.  Or, a 
trigger may made that goes off when an enemy is dead, or the player is in a certain part of map.

Other types of colliders may be based on proximity.

===========================

Level objects

Level is a Scene subclass.

Factory methods to:

Create background and foreground scenery layers from tmx file.

The tmx file would basically be a format to specify the contents of the level.

A dictionary of the format:

{
'entity': Entity,
'sprite': SpriteComponent
...
}

could be used to create entities and components from a simple text file.

Or factor that out into another module which creates those entities and builds a Level from
the text file that uses the factory methods of Level.  Hard to say how to implement that without
more work on the entities and components themselves.

=============================

MapCollider optimization

Select 0

L3 1

R3 2

START 3

UP 4

RIGHT 5

LEFT 6 ?

LEFT 7 ?

L2 8

R2 9

L1 10

R1 11

TRIANGLE 12

CIRCLE 13

EntityManager API improvement

add method:
    
    entities_with(Position, Velocity, ..., Sprite)
    
    which returns a list of dictionaries with the format:
    
    {
        id: e_id,
        pos: pos_instance,
        vel: vel_instance,
        ...,
        sprite: sprite_instance    
    }

entities_with will return none if no matches could be made, and only returns the components
for an entity that has all of the components given.