Lua扇形判定：技能范围的距离加角度双条件

local function inSector(actor, tx, ty)
    local dx, dy = tx - 200, ty - 200
    return dx * dx + dy * dy <= 15 * 15   -- 只判距离，身后也命中
end

local function inSector(cx, cy, face, tx, ty)
    local dx, dy = tx - cx, ty - cy
    if dx * dx + dy * dy > 15 * 15 then return false end
    local ang = math.abs(math.atan(dy, dx) - face)
    if ang > math.pi then ang = 2 * math.pi - ang end
    return ang <= math.pi / 4      -- 半张角45度
end
sendmsg(actor, 1, "扇形命中："
    .. tostring(inSector(200, 200, 0, 210, 204)))