transition 过渡

transition

类型: MethodDeclaration

所属类: CommandFunctionList

定义位置: command.ts

描述

过渡

参数

参数名	类型	描述	默认值
\{variable, start, end, easingId, duration, commands\}	`{
variable: VariableGetter
start: number | VariableGetter
end: number | VariableGetter
easingId: string
duration: number | VariableGetter
commands: CommandDataList
}`	-	-

返回值

类型: CommandFunction \| null

源代码

位置: 第 3989 行

protected transition({variable, start, end, easingId, duration, commands}: {
    variable: VariableGetter
    start: number | VariableGetter
    end: number | VariableGetter
    easingId: string
    duration: number | VariableGetter
    commands: CommandDataList
  }): CommandFunction | null {
    if (commands.length === 0) {
      return null
    }
    const context = Command.stack.get()
    const nextCommands = context.commands
    const nextIndex = context.index + 1
    const getStart = Command.compileNumber(start)
    const getEnd = Command.compileNumber(end)
    const getDuration = Command.compileNumber(duration)
    const setNumber = Command.compileVariable(variable, Attribute.NUMBER_SET)
    const setVariable: CommandFunction = () => {
      const transition = CurrentEvent.transitions![0]
      transition.elapsed -= CurrentEvent.timer!.duration
      const {start, end, duration} = transition
      const easing = Easing.get(easingId)
      const time = easing.get(transition.elapsed / duration)
      const value = start * (1 - time) + end * time
      setNumber(value)
      return true
    }
    const checkLoopCond = () => {
      const {elapsed, duration} = CurrentEvent.transitions![0]
      if (elapsed < duration) {
        CommandIndex = 0
        return CurrentEvent.wait(0)
      } else {
        CurrentEvent.transitions!.shift()
        CommandList = nextCommands
        CommandIndex = nextIndex
        return true
      }
    }
    const loopCommands = Command.compile([setVariable, ...commands] as CommandDataList, checkLoopCond)
    return () => {
      const duration = getDuration()
      if (duration > 0) {
        if (!CurrentEvent.transitions) {
          CurrentEvent.transitions = []
        }
        CurrentEvent.transitions.unshift({
          elapsed: 0,
          start: getStart(),
          end: getEnd(),
          duration: duration,
        })
        const timer = CurrentEvent.getTimer()
        timer.duration = 0
        CommandList = loopCommands
        CommandIndex = 0
      }
      return true
    }
  }

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文档生成时间：2025/7/7 12:07:06