Monday, October 25, 2010

Open-source camp battle has begun


Recently, the software industry's largest companies have aside your traditional moves, take the initiative to open-source camp shook olive branch.

JavaOne Conference, held in the near future the opening ceremony, Sun's president announced that the company's open source technology strategy, and officially released the Java System Application Server Platform Edition of open source.

July 4, Oracle announced that, as a commitment to Java developers, the company will be free and open to all developers Oracle JDeveloper 10g. In addition, Oracle is planning to take the lead in Eclipse Foundation open source community in the implementation of JavaServer Faces (JSF) interface.

BEA has announced a package will be developed to support the industry's first comprehensive framework for all major open source J2EE application environment, this series of new tools will allow developers to one or more of the industry's leading open source Java framework for the preparation of procedures and can easily develop their application deployment in the BEA mixed application server.

IBM's approach is more direct, the acquisition of Gluecode this open source application server products, the commitment to continue to adhere to the product's open source policy, to become the entry-level enterprise application server products.

The performance of vendors are said to open-source camp is good, not because they want to change their strategy, but open-source represents a powerful application behind the power, can only follow this power, or will not, either .

A survey shows that the world's top 2,000 companies in more than 70% of the use of one or more open source frameworks - as many as 28% of companies in the development environment used more than one application server.

Open source products, users are proliferating, many enterprises are currently using open source products, such as Cisco and Intel that even large companies are also users of open source products, also conceivable that some of the cost is very sensitive to small enterprises will be more inclined to use open source products to build the initial IT infrastructure.

A few years later, with the growth of these enterprises, will face the problem of product improvement, then the use of open source a good experience during the establishment of these companies have chosen to become a commercial-grade software products important basis. More importantly, with the growing open-source camp, the camp had a number of major application projects, and thus there will be a number of important processes and tools are open source Java, and on these procedures and tools support the expansion of its product is undoubtedly a good way to influence. A few years later, the software license sales of software vendors no longer the main income, but if there is enough influence and voice, not afraid of no user. So the question now is how to compete for the greatest support to the open source camp.






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Tuesday, October 19, 2010

Seven types of IP congestion control algorithm needs to be improved


Network congestion caused by DDoS attacks, malicious hosts controlled by the machine caused by a large number of puppets, not in the traditional sense of the end to end congestion, we can only control the router, or IP-based congestion control to achieve. The current mainstream of seven IP congestion control algorithms are needed to improve before they can be used effectively to prevent DDoS attacks.

Distributed Denial of Service DDoS (Distributed Denial of Service) attack is regarded as the greatest threat facing the Internet is one.

There are some common methods of DDoS attacks and defense mechanisms, including: prevention by modifying the configuration and protocol attacks, the source of the reverse lookup attack, attack detection and filtering, distributed attack detection and filtering (Host / router side) and so on.

DDoS attacks and network congestion

Generate the root causes of network congestion to the network is to provide the load over the network, storage and processing power, increase the performance of invalid packets, packet delay increases with the loss, and decreased quality of service. If at this time can not take effective detection and control methods, will lead to congestion has been increasing, and even cause system crashes, under normal circumstances the formation of the three direct causes of network congestion is:

鈼?router memory space. Need some input data stream with an output port, if the entry rate is greater than the export rate, it will build in the port queue. If you do not have enough storage space, data packets will be dropped, especially on the burst data stream. Increase storage space on the surface seems to be able to resolve this contradiction, but according to Nagel's research, if the router has unlimited storage capacity, the congestion will only become worse.

鈼?the relative lack of bandwidth capacity. Intuitively, when the data input bandwidth greater than the total output bandwidth, the network will form a low-bandwidth bottleneck link Office, network congestion occurs, relevant information that may refer to Shannon theory.

鈼?processor processing capability is weak. If the router's CPU cache in the implementation of the queue, update the routing tables and other operations, the processing speed can not keep up high-speed link will result in congestion. Similarly, low-speed links for high-speed processors will also have congestion.

These are the early Internet network congestion in the three main reasons. This, TCP congestion control gives a good solution. In practice, if all end users are complying with or compatible TCP congestion control mechanism, network congestion can be well controlled. However, when network congestion caused by DDoS attacks when, TCP window-based congestion control mechanism which can not be resolved. The reason is the congestion caused by attacks from malicious hosts send a large number of data caused not only these hosts will not be completed under the TCP congestion control mechanism for coordination of work, or even itself may contain a forged source address, to increase the amount of data sent, increase the number of connections and other attacks. In this case, the DDoS attack network congestion caused by the router must be processed, it is only IP-based congestion control to achieve.

Note that, DDoS attacks on network congestion caused by the above analysis is different from the ordinary case, there are substantial differences between them. In contrast, DDoS attack caused by congestion, often attacking the data packet size, arrival time, and many other aspects of the protocol type has some relevance, it is a distributed denial of service determined by its own characteristics. Ordinary case of network congestion, the data is not controlled by multiple attackers sent, and therefore does not have the similar correlation of. Congestion caused by attacks carried out protection, we should first find the correlation between, on the basis of traditional congestion control mechanism is introduced and refined in order to be efficient and accurate detection and control.

Seven mainstream IP congestion control algorithm and evaluation

According to the principle and mechanism of DDoS attacks, mechanisms of protection of the ability to do evaluation should be reference to the following criteria: condition 1, whether the feature according to certain rules setting; second condition, whether in accordance with certain rules to distinguish between the data flowing through ; conditions for three different types of data packets, it can provide different priority services. If a congestion control mechanism to meet these three conditions, we basically have a protective DDoS attacks.

The following will give a brief analysis of the current number of mainstream IP congestion control algorithm and its protection evaluation of the feasibility of DDoS attacks:

鈼?FIFO FIFO (First In First Out)

Traditional FIFO strategy is currently the most widely used Internet as a service model. Its biggest advantage is ease of implementation, but is essentially a FIFO "to end" (Drop-tail) of the algorithm, so when unexpected data arrives prone to the phenomenon of packet loss, the fair is poor, on the upper the TCP fast recovery and lower efficiency.

Evaluation criteria were known, the algorithm does not meet either condition, too simple and lack of intelligence, can not for the DDoS attack protection.

鈼?Random Early Detection RED (Random Early Detection)

RED algorithm is a certain probability into the router discards the packet. RED's early design idea is to avoid the continuous drop of the same connection packet, thereby enhancing the throughput of the connection. Packet loss rate through the assessment, RED can get better at the connection between fairness, strong adaptability to the unexpected business. RED also some disadvantages, such as may cause network instability, and select the appropriate configuration parameters is not an easy task. In recent years, researchers have proposed many improved RED algorithm, these algorithms are to some extent, from different aspects to improve the performance of RED.

Evaluation criteria were known, this method is not protective effect of DDoS attacks, because the idea is the assessed packet loss rate, normal business and attack data "too fair" and could not be differentiated, enabling a large number of normal business in the attack occurs can not be service.

鈼?Explicit Congestion Notification Algorithms in ECN (Explicit Congestion Notification)

The first two congestion control algorithms are adopted to tell the end of the system packet loss, network congestion has occurred. The Explicit Congestion Notification Algorithm congestion prompted by a clear (RFC2481) to implement congestion control, on the one-time effect of large-volume data transmission ideal, but there are certain requirements on the delay.

The algorithm embedded in the source side packet ECN, a router based on network conditions set by the CE (Congestion Experienced) bit. Source termination received feedback from the network to come back home this CE-bit data packet, it will then send the packet marked as dropped packets. ECN's advantage does not require retransmission timeout, not dependent on the coarse-grained TCP timer, so there is some delay in the applications required better performance. On this basis, also proposed another improved algorithm, it by adjusting the size of congestion window CWND, to correct a long RTT of TCP connection error, to improve the sharing of bottleneck bandwidth fairness.

Evaluation criteria were known, this method is not protective effect of DDoS attacks, because no signatures to identify and distinguish the functions, when the attack occurred less intelligence.

鈼?fair queuing algorithm FQ (Fair Queuing)

FQ algorithm in the routers for each output line queues have built one. When a line is idle, the router back and forth to scan all queues, each team in turn will send the first package. FQ bandwidth independent of packet size distribution, services began almost simultaneously in the queue. Therefore, in the case of statistical multiplexing without the expense of providing additional equity, and end to end congestion control mechanisms can be better coordinated. The disadvantage is that to achieve them are complex and require line of each data stream, and each stream of state statistics, packet classification and packet scheduling overhead and so on.

Evaluation criteria were known, this method is not protective effect of DDoS attacks, because the same ECN Act.


鈼?weighted fair queuing algorithms WFQ (Weighted Fair Queuing)

Weighted fair queuing algorithm is FQ Algorithm. According to different data streams of different bandwidth requirements, queue for each queue cache resource allocation by applying the weighting to increase the adaptability of FQ on the different applications, the algorithm there are other improved algorithm.

Evaluation criteria were known, the method can be used for protection by improved DDoS attack idea is first to detect and classify attacks, and then import the data according to attack the data, normal data, were queuing up three types of suspicious data processing, data directly on the attack discarded, while data on suspicious and normal to give a certain weight, to provide different quality of service. Good performance in the router to handle the case of ability, or even a more complex and intelligent processing strategies, such as multi-priority queue.

鈼?weighted random early detection WRED (Weighted Random Early Detection)

Is the random early detection combined with priority queuing, this combination provides a high-priority packet priority communication services capabilities. When an interface congestion began to appear, it selectively discard lower-priority group, rather than simply randomly dropping packets.

Evaluation criteria were known, the method can be used for protection by improved DDoS attacks, ideas and WFQ similar, they all meet the conditions of the three evaluation criteria, should be increased to improve the conditions and terms of a second set.

鈼?custom queuing

Custom queuing is allowed to have a minimum bandwidth and latency requirements of different applications sharing the network designed. Custom queuing for the distribution of different protocols with different queue space and queue a revolving manner, when a specific protocol data stream is allocated a larger queue space, also received a higher priority services, custom queuing priority queue more than fair. Custom queuing can guarantee that each particular type of communication can be fixed bandwidth, while in the case of link tension and avoid the data stream attempt to limit the amount beyond the possibility of pre-allocation.

Evaluation criteria were known, the method can be used for protection by improved DDoS attacks, are used in resource allocation and priorities for different businesses weighted to improve ideas and WFQ and WRED similar.

7 Ways addition to the above, there are other ways. If the FQ and the RED algorithm to combine Flow RED algorithm, it will cache into several queues, then each data stream using RED algorithm, simulation results show the fairness of its good; and if the core stateless fair queuing algorithms CSFQ (Core-Stateless Fair Queuing) border routers in the network to perform data flow management, and in the core does not do much more.

Can be seen, the protective ability of these algorithms, there are big differences between any of them need to improve before they can be effectively used to control DDoS attacks caused by network congestion.






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Tuesday, October 12, 2010

Let the spirit soar your football career


2006 World Cup in Germany will pull heavy curtain, 32 princes Sabre-rattling, determined to win. Running, cheering, shouting, competitive ... ... There is no weak, here refused to mediocrity! The spirit of football is full of charm us is fresh, strong, is forging ahead, passion, hard work ... ...

Workplace football spirit soar

World Cup's influence, sometimes not only because of football, it may be more because of a team, a player who saw a force, a state of mind, and spirit to our shock Let us admire.

Hard achievements dream

Football there is passive, there is a low profile, there is no love publicity, but by no means weak! German football stressed the strong reason, even if only the last second game, they will not give up, fight more than, more than offensive; Italy, and perhaps always a step away from success, yet they have no pain and regret, he brought people more are in the dark see the light; Korean arena everybody roam, struggling to scramble, indomitable, they are calm and stable no matter win or lose, for them, the struggle is an invaluable asset.

姣嬪焊澶氳█锛屽湪鑱屽満涓紝杩涘彇涓庢嫾鎼忎篃鏄瘡涓汉蹇呬笉鍙己鐨勬綔璐ㄣ?姣斿鍥介檯鎶曡祫閾惰涓氾紝鏈鐢熸渶鍒濆紑濮嬬殑骞磋柂鍦?.5涓囩編鍏?5涓囩編鍏冧箣闂达紝钁d簨鎬荤粡鐞嗙殑鍩烘湰骞磋柂閮界淮鎸佸湪20涓囩編鍏冧互涓娿?浣嗗浗闄呯煡鍚嶆姇琛岀殑鍒嗘瀽甯堟瘡澶╁伐浣滄椂闂撮暱杈?4-18涓皬鏃躲?涓旀姇璧勯摱琛岃幏鍙栦汉鎵嶄竴鏄鏂版墜杈瑰共杈瑰锛岃嚜宸变簤鍙栨満浼氾紝鍍忔父娉充竴鏍凤紝娓稿緱鍑烘潵灏卞嚭鏉ワ紝娓镐笉鍑烘潵灏辨饭姝伙紱鍙︿竴涓垯鏄寲浜恒?杩欎釜琛屼笟闇?绮惧姏鍏呮矝銆佺儹鎯呭悜涓娿?瀛﹁瘑涓板瘜涓庨珮搴﹁嚜寰嬶紝甯傚満绔炰簤寮傚父娈嬮叿銆傚綋鎴戜滑鎰熷徆鐫?粬浠殑楂樿柂銆佷笓涓氥?绮惧共銆佹笂鍗氫箣鏃讹紝鍙浘鎯宠繃鑷繁鐨勪粯鍑哄張鏈夊灏戯紵

鍏跺疄鑱屽満涓婅浜洪儊闂风殑淇℃伅鏈夊緢澶氾紝2006骞村叡鏈?13涓囧ぇ瀛︽瘯涓氱敓瑕佸氨涓氾紱鍑犱釜鏄?amp;quot;杩囧姵姝?amp;quot;鑱屼笟鍙堥甯冿紱绻侀噸鐨勫伐浣滃帇鍔涳紱闅惧鐨勫悓浜嬪叧绯烩?鈥︺?灞傚嚭涓嶇┓鐨勯棶棰樹技涔庢?鏄瘮璁╀汉鎰夊揩鐨勪簨鎯呭锛屼絾鍚屾椂鎬绘湁閭d箞涓?儴鍒嗕汉锛屼粬浠粠鏉ユ病鏈夋秷鏋佸Ε鍗忥紝浠庢潵涓嶈偗杞绘槗鏈嶈緭锛屼粬浠Н鏋佷富鍔ㄣ?涔愯鍚戜笂銆佸叏鍔涙嫾鎼忥紝浠栦滑涔熻浼氭湁鐘硅鲍锛屼絾鍐充笉浼氭斁寮冨姫鍔涖?

鍥㈤槦 閾搁?浼犲

瓒崇悆鏈韩璁╀汉蹇箰锛岃?鍥㈤槦绮剧鍒欐槸瓒崇悆鐨勭伒榄傘?浠讳綍涓?満姣旇禌锛屽鏋滄病鏈変竴涓洟闃熺殑鎵撴嫾锛屽啀浼樼鐨勯槦鍛樹篃闅炬姷鍔叉晫銆傚痉鍥借冻鐞冧竴鍚戜互鍥㈤槦绮剧鑰岃憲鍚嶃?鑽峰叞鐨勫叏鏀诲叏瀹堛?闃挎牴寤风殑閽㈤搧涔嬪笀銆傚洟闃熺簿绁炴鏄冻鐞冪湡姝g殑绮鹃珦鎵?湪銆?br />
鍏跺疄锛屽浜庝竴涓洟闃熻?瑷?紝鏈?嵄闄╃殑浜嬫儏鑾繃浜庡唴閮ㄤ笉鍜岋紝鍐呴儴鍥㈢粨锛屽畾鑳芥敾鏃犱笉鍏嬶紝鍐呴儴涓嶅拰锛屽繀鐒惰閿愭皵鍙楁崯锛屼笉鎴樿?灞堜汉涔嬪叺銆傚洟闃熸棦闇?浼樼鐨勬垚鍛樺啿閿嬮櫡闃碉紝涔熼渶瑕佸崜瓒婄殑棰嗗杩愮甯峰箘銆傛煶浼犲織鏈?垵璁╂潹鍏冨簡鍒嗙鑱旀兂锛岃?閮负鍒嗙绁炲窞鏁扮爜鍙互璇存槸鎴愬姛鐨勭鐞嗘渚嬶紝鑰岀墰鏍圭敓绂诲紑浼婂埄鍒涚珛钂欑墰锛屽浼婂埄鑰岃█鍦ㄧ鐞嗕笂灏变笉瓒崇О閬撱?

瑙勫垯 鎻愬崌瑙勬牸

瓒崇悆姣旇禌涓紝瀵逛簬鍦哄湴銆佹椂闂淬?浜烘暟銆佽澶囥?瑁佸垽鍛樸?璁¤儨鏂规硶绛夌瓑閮芥湁涓ユ牸鐨勮瀹氾紝鎵嶄娇瓒崇悆姣旇禌澧炲己浜嗗緢澶氱珵鎶??鍜屽叕骞虫?锛岄槦鍛樿涪鐨勭棝蹇紝澶у鐪嬬殑寮?績锛岃儨鍑虹殑浜哄績瀹夌悊寰楋紝娣樻卑鐨勪汉鍙f湇蹇冩湇銆?br />
浜嬫湁鍙负涓庝笉鍙负锛屾墍浠ヨ閬靛惊娓告垙瑙勫垯銆傝冻鐞冨満涓庤亴鍦猴紝铏界劧鐜涓嶅悓锛岃韩浠戒笉鍚岋紝浣嗘父鎴忚鍒欏嵈鏈夌浉鍚屼箣澶勩?姣斿鍥㈤槦绮剧锛涙瘮濡傚悰瀛愮埍璐?鍙栦箣鏈夐亾锛涙瘮濡傝鍠勪簬涓庝汉娌熼?锛涙瘮濡傛垝楠勬垝韬侊紝鎻愰珮鑷韩绱犺川锛涙瘮濡傝闅忔椂鎺ュ彈鏂扮殑鎸戞垬锛涙瘮濡傝鏈夋竻鏅扮殑鐩爣锛屽苟涓庝粬浜哄垎浜祫婧愨?鈥﹀鏋滆兘澶熸噦寰楄繖浜涙父鎴忚鍒欙紝鑱屽満鎵撴嫾灏变細鏇村寮?績锛岃?灏戝緢澶氭?鎵嶄笉閬囩殑鎶辨?銆?br />
绔炰簤 瓒呰秺"绾㈡捣"

鏈変汉璇?amp;quot;鍦ㄥ拰骞冲勾浠o紝瓒崇悆灏辨槸涓?満鎴樹簤"锛岃冻鐞冩湁鎴樻湳銆侀樀褰?鍥㈤槦鈥︹?鏇存湁鍥芥皯鐨勬敮鎸侊紝鍏跺奖鍝嶅姏鐪熸槸涓嶅彲灏忚銆備絾濡傛灉涓?釜鐞冮槦瓒冲寮哄ぇ锛屽畠灏嗕笉浼氬悜鑷韩涔嬪鐨勪换浣曚汉瀵绘眰瀵规墜銆傚反瑗夸汉瀵硅冻鐞冪殑鐑埍璁╀汉闄堕唹锛屾敾鍔胯冻鐞冦?鑹烘湳瓒崇悆銆佹宸磋冻鐞冿紝宸磋タ闃熺殑鐞冨憳鎬绘槸鎵嶅崕妯孩婵?儏鍥涘皠锛屼粬浠弽澶嶈繘鏀诲拰琛ㄦ紨锛屾牴鏈毦浠ュ仠鎵嬨?瀵逛簬浠栦滑鑰岃█锛屾瘮璧涘氨鏄〃婕旓紝瓒崇悆灏辨槸蹇箰锛屽嵆浣垮湪绔炰簤涓篃鑳戒繚鎸佽垶韫堣埇鐨勯鏍硷紝鏃犳嫎鏃犳潫銆佽嚜鐢卞鏀俱?

宸磋タ浜虹殑鎴愬姛婧愪簬瀵硅冻鐞冪殑鐑埍锛屼絾涓嶆槸瀵规煇涓珵浜夊鎵嬬殑鍏虫敞锛屾?鎯宠嚧鍔涗簬鍑昏触瀵规墜锛屽洜涓哄叾鐙殬锛屾敞瀹氶毦浠ユ垚鍔燂紝鍦ㄨ亴鍦轰腑灏ゅ叾濡傛銆傘?钃濇捣鎴樼暐銆嬫寚鍑猴紝"鎯冲湪绔炰簤涓眰鑳滐紝鍞竴鐨勫姙娉曞氨鏄笉瑕佸彧椤剧潃鎵撹触瀵规墜"锛屼笉瑕佸彧鎶婄洰鍏夋斁鍦ㄧ幇瀛樼殑浜т笟杩欑墖"绾㈡捣"閲岋紝鑰屾槸榧撳姳浼佷笟瑕佸媷浜庤埅鍚戞湭鐭ョ殑甯傚満绌洪棿锛屽彂鎺樼洰鍓嶄粛鐒剁湅涓嶅埌鐨勪骇涓氾紝浜﹀嵆鍟嗘満鏃犻檺鐨?amp;quot;钃濇捣".澶氬叧娉ㄧ珵浜夊鎵嬶紝涓嶅澶氬叧娉ㄨ嚜宸卞拰鏇村箍闃旂殑甯傚満锛屽叾瀹為珮鎴愰暱鍏徃鍙姳璐瑰緢灏戠殑娉ㄦ剰鍔涘湪绱х洴鎴栨墦璐ュ鎵嬶紝浠栦滑鍙嶈?浼氶?杩囦环鍊煎垱鏂帮紝璇曠潃璁╃珵浜夊鎵嬪彉寰楁棤瓒宠交閲嶃?

鎴愬姛 鏉ヨ嚜琛屽姩

涓栫晫鏉繕娌℃湁寮?锛屽痉鍥界墿鐞嗗瀹舵墭鍏板氨鏍规嵁涓?釜鐗╃悊瀛︽ā鍨嬭绠楀緱鍑虹粨璁猴紝寰峰浗闃熷皢鏈?6.8锛呯殑鏈轰細澶哄緱涓栫晫鏉紱鑰岃嫳鍥藉コ鐜嬩篃瀵广?娉版櫎澹姤銆嬭〃绀猴紝濡傛灉璐濆厠姹夊甯﹂鐨勮嫳鏍煎叞瓒崇悆闃熻兘澶熷ず鍐狅紝濂瑰皢鍦ㄧ櫧閲戞眽瀹鐞冨憳浠枬鑼讹紱娉曞浗闃熷湪闃垮皵鍗戞柉灞辫繘琛岄泦璁紝涓绘暀缁冩壃瑷?湁淇″績甯﹂鐞冮槦闂叆鍐宠禌鈥︹?鍏跺疄姣忎釜闃熷憳閮芥湁璧㈠緱鑳滃埄鐨勬鏈涳紝浠栦滑鐨勭洰鏍囬兘鐬勫噯鐫?-澶у姏绁炴澂銆?br />
鑰屽湪鑱屽満涓紝瀵规垚鍔熺殑杩芥眰鍏跺疄涔熸槸鍊煎緱鎺ㄥ磭鐨勪簨鎯咃紝浣嗚鍔ㄦ洿涓洪噸瑕併?瀵逛簬涓汉锛屼竴瀹氳鏈夎嚜宸辩殑鐩爣涓庤鍒掞紝浣犵幇鍦ㄥ湪鍝紵浣犺鍒颁粈涔堝湴鏂癸紵鎬庢牱鎵嶈兘鍒拌揪閭i噷锛熶綘鐜板湪璇ュ仛浠?箞锛熸湁浜嗙洰鏍囦笌琛屽姩锛屼釜浜烘墠涓嶈嚦浜庤糠澶辨柟鍚戙?鑰屼綔涓轰竴涓洟闃燂紝鍙湁鐩爣娓呮櫚锛屾姝ュ彲琛岋紝鎵嶈兘璋冨姩闃熷憳婵?儏锛屾洿澶氫汉鎰挎剰涓哄洟闃熻?鎴樸?

杩欑绉嶈冻鐞冪簿绁烇紝浠夸經鏈夊姏鐨勫憪鍠婁笌鐕冪儳鐨勬縺鎯咃紝鐢辫繙鑰岃繎锛岃鎴戜滑鍦ㄤ技涔庢贩娌岀殑鑱屽満涓彉鐨勬竻閱掋?鍙樼殑鐫挎櫤銆佸彉鐨勬湁鍔涖?






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Monday, October 11, 2010

Getting Started with Corel Draw 10 (4) hands to create vector graphics (1)


After the previous explanation, I believe we already know of several functional modules CorelDRAW, and now with the use of previous knowledge to create their own vector graphics it!

Let's look at renderings, is a reflection in the water of the city night. Production need to use the main tools: rectangle tool, circle tool, polygon tool, interactive tools to reconcile.



First, draw the city's buildings

Figure with Rectangle tool to draw a few boxes of different sizes, select them, through the Arrange -> Align & Distribute dialog transferred out of alignment distribution, select the Botton (the bottom of the alignment), confirmed, the right Click the center of these objects control points inside the pop-up menu select the Group (Group) to enable them to always together.



The next drawing of the building windows, steps slightly more complicated, but it is a key part of the work, please watch carefully the presentation:
A tool to draw a small rectangular box;
2 mouse to move the center of the rectangle, the direction will become a cross-type, click the left mouse button and hold down the Ctrl key, then turn right drag the small box to the right place, then do not release the left mouse button , press the right mouse button, the cursor will turn into an arrow with the +, release the hand, a level of alignment with the original box the box will be copied out.
3 Select the interactive reconciliation tool, click the box to the left, following the left mouse button drag to the right of the box, the box 20, like first touch was "reconciled" out.
420 ideographic too much to reconcile in the property column enter the number of which 4, press Enter, you draw 4 squares of the harmonic.
5 Right-points in the second box, inside the pop-up menu choose Break Blend Group Apart (dispersed harmonic group).
6 again, right-click the second box, inside the pop-up menu select Group (group).
7 Repeat step 2, copy the line in the box below
8 Repeat step 3, interaction in the two groups to reconcile the use of grid to generate a square matrix.



Note: The above operation looks a bit to find people to feel not mind, now look at some explanations related to

On the Ctrl key:

Drag the object while holding down the Ctrl key, the object is bound into either move up or down, or move around, but not both simultaneously move in both directions.
Rotate the object while holding down the Ctrl key, rotate will be fixed at 15 degree increments of rotation, in the Tools-> Options-> Edit-> Constrain Angle 15 degrees on the default to be modified.
Change when the object size, size will be integer multiples of the scale.
When creating graphics 鎸夌潃 Ctrl key to create a working graphics, such as square, are round (instead of ordinary rectangular and oval)
Using the Interactive Fountain Fill (interactive gradient fill) hold down the Ctrl key when, filling the angle will be 15 degree increments.
Select an object (the object then appears around the control handle 8), hold down the Ctrl key, the control handle relative to the direction of dragging a control handle, you can create objects in horizontal, vertical and 45 degree mirror.
Step 2 complex on mouse operations:

Drag an object and click before releasing the left-right, it will copy an object, another with a small + sign on the keyboard can also copy an object.

On the "beaten to reconcile group":

Harmonic generated by using two objects, can be seen as a special relationship with associated groups, the group which all objects are the source and destination object shape, color, location control, can not be independent. When we do not need this kind of restraint when you can use the "broken up reconciliation group" to make ordinary objects into groups.

Note: Harmonic group does not include source and destination object

About Group (Group) interaction reconcile:

Harmonic can be used for group interaction, the above step 6 is to reconcile before the group, the source and destination object group up, then talk to another group to interact reconcile.

Are coupled to each one building windows, and group together all the windows, and finally get this results:










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