vectron

simple vector-based game engine, made with node-sdl

the engine itself runs on 128x128 resolution, but rescales to fit current window

basic usage

node index.js path, where path is the path to the app file

if no path is specified, it will default to apps/demo.js

api reference

apps run at 50 FPS by default, that can be changed by setting __FRAMERATE and including in the export

```
class Vector
```
- basic line segment object
- ```
constructor(Number x1,Number y1,Number x2,Number y2): Vector
```
- Vector.prototype.draw()
  - Renders a white line segment from (x1,y1) to (x2,y2)
  - A line segment is only rendered for 1 frame
- Vector.intersect(Vector v1,Vector v2)
  - Checks if v1 intersects with v2
- Vector.isBetween(Vector v1, {x: Number, y: Number})
  - Checks if point (x,y) is part of v1
- Vector.isEdgeTouching(Vector v1, Vector v2)
  - Checks if any of both edges from v1 touch any point from v2
- Vector.(add/sub/mul/div)(Vector v1, Vector v2)
  - Adds, subtracts, multiplies or divide v1 by v2
```
keydown(String key): Boolean
```
- Checks if that key is pressed. Keys from node-sdl

events

every single event gets runs with this set to {Vector,keydown}, so both Vector and keydown are only accessible from inside the functions

```
start()
```
- This function only runs once, at the start of the execution of the app
```
update(dt)
```
- This function executes every frame of the app, with a deltaTime argument
```
fixedupdate(fdt)
```
- This function executes with a constant framerate, regardless of the current window framerate, with a fixedDeltaTime argument
```
end()
```
- This function executes before the current window closes (great for destroying Speaker instances)

example app

//generates lines randomly scattered around the screen

const __FRAMERATE = 50

const start=()=>{}
const end=()=>{}
const fixedupdate=()=>{}

function update(){
    const r=()=>Math.floor(Math.random()*128)
    const v = new this.Vector(r(),r(),r(),r())
    console.log(v)
    v.draw()
}

module.exports={start,end,fixedupdate,update,__FRAMERATE}