冰壶对决：一壶定音

fx-curling

local Curling = {}
local KEY = { FRICTION = 0.55, MIN_SPD = 6, R = 15 }

function Stone.Step(s, dt)
    if s.stopped then return end
    local sp = math.sqrt(s.vx * s.vx + s.vy * s.vy)
    if sp <= KEY.MIN_SPD then
        s.vx, s.vy = 0, 0
        s.stopped = true
        SL:PlayFxAt("stone_stop", s.x, s.y)
        return
    end
    s.x = s.x + s.vx * dt
    s.y = s.y + s.vy * dt
    -- 指数摩擦: 速度按比例衰减, 滑行轨迹是平滑的减速曲线
    s.vx = s.vx * (1 - dt * KEY.FRICTION)
    s.vy = s.vy * (1 - dt * KEY.FRICTION)
    -- 冰屑尾迹
    if math.random() < dt * 20 then
        SL:PlayFxAt("ice_dust", s.x - s.vx * 0.06, s.y - s.vy * 0.06)
    end
    -- 壶间碰撞: 沿法线传递动量
    for _, o in ipairs(SL:GetValue("stones")) do
        if o ~= s and not o.stopped == false then
            local dx, dy = o.x - s.x, o.y - s.y
            local d2 = dx * dx + dy * dy
            if d2 < (KEY.R * 2) ^ 2 and d2 > 0.01 then
                local d = math.sqrt(d2)
                local nx, ny = dx / d, dy / d
                local dot = s.vx * nx + s.vy * ny
                if dot > 0 then
                    o.vx = o.vx + dot * nx * 1.4
                    o.vy = o.vy + dot * ny * 1.4
                    o.stopped = false
                    s.vx = s.vx - dot * nx * 0.7
                    s.vy = s.vy - dot * ny * 0.7
                    SL:PlaySfx("stone_clash")
                end
            end
        end
    end
end

function Curling.Judge()
    -- 全部停稳后: 离圆心最近且在营垒内者胜
    local best, bd = nil, 1e9
    for _, s in ipairs(SL:GetValue("stones")) do
        local d = math.sqrt((s.x - SL:GetValue("houseX")) ^ 2
                          + (s.y - SL:GetValue("houseY")) ^ 2)
        if d < SL:GetValue("houseR") and d < bd then
            bd = d; best = s
        end
    end
    if best then SL:ShowSystemTips(best.color == "blue" and "我方领先" or "对方领先") end
end

return Curling