add animation

game/animation.lua

@@ -0,0 +1,80 @@
+local hazel = require "hazel"
+
+---@class Animation
+local _M = {}
+
+---@class Frame
+---@field row number
+---@field col number
+---@field time number
+
+---@param tilesheet Texture
+---@param frames table<Frame>
+function _M.CreateAnimation(tilesheet, frames)
+    local o = {tilesheet = tilesheet, frames = frames, index = 1, counter = 0, isPlaying = false}
+    setmetatable(o, {__index = _M})
+    return o
+end
+
+---@param self Animation
+function _M.Play(self)
+    self.isPlaying = true
+end
+
+---@param self Animation
+function _M.Stop(self)
+    self.isPlaying = false
+    self.index = 1
+    self.counter = 0
+end
+
+---@param self Animation
+function _M.Pause(self)
+    self.isPlaying = false
+end
+
+function _M.GetCurFrame(self)
+    if self.index > #self.frames then
+        return self.frames[#self.frames]
+    else
+        return self.frames[self.index]
+    end
+end
+
+function _M.GetTilesheet(self)
+    return self.tilesheet
+end
+
+---@param self Animation
+function _M.Rewind(self)
+    self.index = 0
+    self.counter = 0
+end
+
+---@param self Animation
+function _M.IsPlaying(self)
+    return self.isPlaying
+end
+
+---@param self Animation
+function _M.Update(self)
+    if not self.frames or not self:IsPlaying() then
+        return
+    end
+    if self.index > #self.frames then
+        self:Pause()
+    end
+
+    self.counter = self.counter + hazel.Time.GetElapseTime()
+    ---@type Frame
+    local curFrame = self.frames[self.index]
+    if not curFrame then
+        return
+    end
+    if self.counter >= curFrame.time then
+        self.counter = self.counter - curFrame.time
+        self.index = self.index + 1
+    end
+end
+
+return _M