mirror of
https://github.com/jiojciojsioe3/a3cjroijsiojiorj.git
synced 2024-11-15 23:41:50 +08:00
68 lines
1.3 KiB
JavaScript
68 lines
1.3 KiB
JavaScript
|
class CanvasCache{
|
||
|
|
constructor(w, h, scale){
|
||
|
|
this.canvas = document.createElement("canvas")
|
||
|
|
this.ctx = this.canvas.getContext("2d")
|
||
|
|
this.map = new Map()
|
||
|
|
if(w){
|
||
|
|
this.resize(w, h, scale)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
resize(w, h, scale){
|
||
|
|
this.map.clear()
|
||
|
|
this.scale = scale
|
||
|
|
this.x = 0
|
||
|
|
this.y = 0
|
||
|
|
this.w = w
|
||
|
|
this.h = h
|
||
|
|
this.lastW = 0
|
||
|
|
this.lastH = 0
|
||
|
|
this.canvas.width = this.w * this.scale
|
||
|
|
this.canvas.height = this.h * this.scale
|
||
|
|
this.ctx.scale(this.scale, this.scale)
|
||
|
|
}
|
||
|
|
get(config, callback){
|
||
|
|
var img = this.map.get(config.id)
|
||
|
|
var saved = false
|
||
|
|
if(!img){
|
||
|
|
var w = config.w
|
||
|
|
var h = config.h
|
||
|
|
this.x += this.lastW + 1
|
||
|
|
if(this.x + w > this.w){
|
||
|
|
this.x = 0
|
||
|
|
this.y += this.lastH + 1
|
||
|
|
}
|
||
|
|
this.lastW = w
|
||
|
|
this.lastH = Math.max(this.lastH, h)
|
||
|
|
img = {
|
||
|
|
x: this.x,
|
||
|
|
y: this.y,
|
||
|
|
w: w,
|
||
|
|
h: h
|
||
|
|
}
|
||
|
|
this.map.set(config.id, img)
|
||
|
|
|
||
|
|
saved = true
|
||
|
|
this.ctx.save()
|
||
|
|
this.ctx.translate(img.x |0, img.y |0)
|
||
|
|
this.ctx.beginPath()
|
||
|
|
this.ctx.rect(0, 0, img.w |0, img.h |0)
|
||
|
|
this.ctx.clip()
|
||
|
|
|
||
|
|
callback(this.ctx)
|
||
|
|
}
|
||
|
|
var z = this.scale
|
||
|
|
config.ctx.drawImage(this.canvas,
|
||
|
|
img.x * z |0, img.y * z |0, img.w * z |0, img.h * z |0,
|
||
|
|
config.x |0, config.y |0, config.w |0, config.h |0
|
||
|
|
)
|
||
|
|
if(saved){
|
||
|
|
this.ctx.restore()
|
||
|
|
}
|
||
|
|
}
|
||
|
|
clean(){
|
||
|
|
delete this.map
|
||
|
|
delete this.ctx
|
||
|
|
delete this.canvas
|
||
|
|
}
|
||
|
|
}
|