piano小程序添加synthNote功能预设

assets/scene_app/piano.lua

@@ -13,6 +13,40 @@ local inst,offset,release
 local instList={'organ_wave','square_wave','saw_wave','complex_wave','stairs_wave','spectral_wave'}
 local presets={}
 
+local scrollSpeed=620
+local disappearDist=-800
+presets.synthNote={}
+---@return Techmino.Piano.Object
+function presets.synthNote.newNote()
+    return {
+        len=0,
+        free=false,
+        _type='synthNote',
+        _update=function(self,dt)
+            local dSize=dt*scrollSpeed
+            self.y=self.y-dSize
+            if self.free then
+                return self.y+self.len<disappearDist
+            else
+                self.len=self.len+dSize
+            end
+        end,
+        _draw=function(self)
+            gc_setColor(self.color)
+            gc_rect('fill',self.x,self.y,self.w,self.len,10)
+        end,
+    }
+end
+function presets.synthNote.press(key)
+    key.note=presets.synthNote.newNote()
+    TABLE.update(key.note,{x=key.x,y=key.y,w=key.w,color=key.fillC})
+    ins(objPool,key.note)
+end
+function presets.synthNote.release(key)
+    key.note.free=true
+    key.note=nil
+end
+
 ---@class Techmino.Piano.Object
 ---@field _type string
 ---@field _update fun(dt:number):any