#+title: Section 04 - Lesson 03 | Physics 2D Nodes
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* Links
- [[../../toc.org][TOC - Godot Notes]]
- [[https://www.udemy.com/course/jumpstart-to-2d-game-development-godot-4-for-beginners/learn/lecture/45069801#overview][S04:L45.03 - video]]

* Notes

** overview
*** assets
1. sprite sheet plane, 3 figures
2. pipe and laser site
3. some backgrounds for parallax effect

*** scenes
1. main game scene
2. plane sceen
3. pipes scene (2 pipes)
4. laser scene

*** approach
- make the basic game scene
- make a plance scene
- code plane movement
- build the pipe / laser / pipes scene
- setup the scrolling logic
- setup collishions and plane death
- create the main screen and setup navigation
- add game over
- add scoring with high score saving
- parallax background

*** plane scene
- falls with gravity
- press a key to jump or fly
- collides with laser, pipes, floor, ceiling
- animated propellor

** physics
*** overview
- gravity
- collisions
- movement
- forces
- impulse
  - get hit by a rocket

*** physics 2D nodes
#+attr_html: :class two-column-definitions
| node type        | definition                                                                                                                      |
|------------------+---------------------------------------------------------------------------------------------------------------------------------|
| StaticBody2D     | Physics body for 2D physics which is static or moves only by script.  Useful for floor and walls.                               |
| CharacterBody2D  | Specialized 2D physics body node for characters moved by script                                                                 |
| AnimatableBody2D | Physics body for 2D physics which moves only by script or animation.  Useful for moving platforms and doors                     |
| RigidBody2D      | Physics body which is moved by 2D physics simulation.  Useful for objects that have gravity and can be pushed by other objects. |

**** StaticBody2D
- wall, rock, ceiling floor, platform in the middle of the level
- designed not to move
- things will bounce or stick to it depending on what your physics is

**** CharacterBody2D
- think platform character
- set the velocities

**** AnimatableBody2D
- inherits from StaticBody2D
- getting a StaticBody and a Character to move together is a pain and buggy

**** RigidBody2D
- tennis ball
- rocket fired

*** how they interact
- interact with other Physics2D nodes
- we DO NOT control the position, the physics engine does
- we supply velocity / force
- physics engine calculates where we go and what our speed / position is