突进残影：一步跨出去的那条影子

mir8-dash

function gameActor:Dash(dist, dirSign)
    if self._dashT and self._dashT > 0 then return end
    self._dashT = 0.18
    self._dashV = dist / 0.18                        -- 突进速度
    self._dashDir = dirSign                          -- 1 右 -1 左
    self._ghosts = {}
end

function gameActor:UpdateDash(dt)
    if not self._dashT or self._dashT <= 0 then return end
    self._dashT = self._dashT - dt

    local nx = self._x + self._dashDir * self._dashV * dt
    if not scene:IsBlocked(nx, self._y) then         -- 突进也认墙
        self._x = nx
    end
    table.insert(self._ghosts, {                     -- 沿途快照
        x = self._x, y = self._y, dir = self._dir,
        frame = self._frame, alpha = 0.55
    })

    local target = scene:FindTargetInLine(self._x, self._y, self._dashDir, 46)
    if target then
        target:Knockback(self._dashDir, 260)         -- 沿突进方向顶飞
        self._dashT = 0                              -- 撞停
    end
end

function gameActor:DrawGhosts()                      -- 残影画在本体之下
    for i = #self._ghosts, 1, -1 do
        local g = self._ghosts[i]
        g.alpha = g.alpha - 0.04
        if g.alpha <= 0 then table.remove(self._ghosts, i)
        else self:DrawFrameAt(g.x, g.y, g.dir, g.frame, g.alpha) end
    end
end