【正文】 mely creating more realistic results。可行的概念方法 有很多 。三維服裝 會(huì) 利 用 某種方式轉(zhuǎn)化為 二維 樣板并標(biāo)明 實(shí)現(xiàn)所需的最后形式 的 結(jié)構(gòu)細(xì)節(jié)。然而，現(xiàn)代CAD 系統(tǒng) 包含了 許多分析工具， 可以 協(xié)助設(shè)計(jì)人員優(yōu)化設(shè)計(jì)或 對 他們的設(shè)計(jì) 進(jìn)行 功能測試。這種系統(tǒng)已 證明 對 制造服裝的企業(yè)非常有效 ，他們?yōu)橛写罅控浳锒?必須從 顧客處 核實(shí)設(shè)計(jì) 的 大型零售機(jī)構(gòu) 生產(chǎn)。 仍然存在著三個(gè)計(jì)算機(jī) 輔助設(shè)計(jì) 很少 涉及 或沒有取得成功的領(lǐng)域。 這些領(lǐng)域 發(fā)展緩慢 導(dǎo)致 了企 業(yè) 無法真正采用計(jì)算機(jī)集成方法設(shè)計(jì)和制造 服裝 。 他們通常把 設(shè)計(jì) 畫在紙上 ， 表達(dá) 服裝 的視覺效果 。這種情況的主要限制有兩個(gè)方面。 3 計(jì)算機(jī)集成方法 這里提出的方法在圖 2 中表示了出來 。下文將詳細(xì)介紹這些因素。 增 加在這些困難 上的 是 服裝在穿著時(shí)的復(fù)雜形狀變化 。 CAD 系統(tǒng)使用 的 技術(shù) （ 如各種形式的雙三次曲面 ） 一定要 能夠準(zhǔn)確地 表現(xiàn)織物懸垂的 形狀， 而不是讓設(shè)計(jì)師完成這些工作 。例如，如果 選中了 兩個(gè)毗鄰的小組件 ，那么系統(tǒng)應(yīng)當(dāng)詢問它們應(yīng)當(dāng)怎樣被連接。首先，它提供了一個(gè)三維框架， 在這個(gè)框架中，樣板 的關(guān)系才能 通過 服裝組成 被 充分 確 定。然而， 這些努力幾乎沒有結(jié)果 ，因?yàn)?二維樣板的生成需要 一個(gè)完整的 3D模型 。 根據(jù)這一劃分， 展開過程中 合體部分和懸垂部分被分開對待 .另一個(gè)重要 因素是 織物的材料特性 。 有人研究過 ， 三維模型轉(zhuǎn)變?yōu)槎S的 平坦算法。 制約機(jī)制，如肩帶，拉鏈。這是一個(gè)非常困難 的要求大量計(jì)算的過程 。 能夠用來準(zhǔn)確描述 材料 特性的參數(shù)是： 經(jīng)紗的方向拉伸應(yīng)變能量不變 ， Ksu；緯線方向拉伸應(yīng)變能量 不變， Ksv；裁剪 應(yīng)變能量不變 ， Kr；平面彎曲 能量不變 ，Kb；由織物單位質(zhì)量產(chǎn)生的潛在能量， Kg。 這個(gè)問題可以通過在 上述清單 中另加入一個(gè)能量部件解決 ， 它可以糾正與模特重合的樣板節(jié)點(diǎn) 。 表現(xiàn)的方法和關(guān)閉它的方法對形成樣板的最終形狀 是很重要的。 以下是 兩個(gè)實(shí)例。在這一階段，表面由多邊形網(wǎng)格 展現(xiàn)出來 。然后 平坦進(jìn)程 開始， 以獲取二維 樣板 。這 個(gè)過程 始于最初三維 樣板 圖 3（ a）， 盡量減少 二維平坦 面料轉(zhuǎn)化為 目前的三維形狀 時(shí)需要的總能量 。 圖 4. 第二個(gè)例子 在圖 4（ a）－（ d）中被展示 。 在展平過程中，省道上的節(jié)點(diǎn)被雙重化，這樣省道才能形成 。設(shè)計(jì)界面 、平展技術(shù) 和懸垂性已被 認(rèn)為是阻礙技術(shù)發(fā)展的主要困難 。 Garment design。 ● an accurate drape engine. For an integrated manufacturing approach to be successful, all three of these difficult elements must be adequately acplished. These elements will now be considered in more detail. . Design interface The design function in the garment industry is a creative and artistic process pared with the equivalent engineering function. So any design system, which is offered to designers, must not be perceived as restraining creative talent or constraining artistic flair. However, designers do operate within certain parameters in terms of cost and functionality of the final product. Superimposed on these difficulties is the plex and amorphous nature of the shape of the garment when worn. Precisely what shape should the designer attempt to convey to a puter system via the design interface? The approach proposed here is to provide the designer with an initial design interface that will enable a full 3D specification of the garment to be specification must be capable of providing an accurate surface description in areas where fit is important, the garment is in close proximity with the underlying mannequin. Such surface descriptions must be capable of specification using existing mathematical techniques using a suitable interface. However, it would be inappropriate for a designer to describe the 3D geometry taken up by areas of the garment where the fabric drapes. Current CAD systems would certainly be able to accurately represent these draped shapes using techniques such as the many forms of bicubic surfaces [1], but it would be unreasonable to expect a designer to tediously specify such ,in order to accurately predict or visualise the shape taken up by the garment, the designer would have to have a very prehensive knowledge of the fabric the purposes of the design interface, it is proposed that representations such as that shown in Fig. 3(a) would be acceptable for initial garment specification asa stylised formwhich would be capable of incorporating all of the constructional detail necessary for manufacture. While notbeingan attempt toaccurately simulatethe 3D appearance of the garment at this point, the design interface should embody functionality to implicitly define all other aspects of the garment specification. For instance, if two abutting panel pieces are defined then there should follow a requirement to nominate how these panels are to be fabric types should be defined for all panels. In effect, this stage should define all of the parameters for a subsequent drape simulation to proceed. The 3D surface representation of the garment displayed at this stage has two important roles. Firstly, it provides a 3Dframework within which panel relationships can be fully defined in terms of the garment position. Also it provides a reasonable starting point for drape ,panel nodes which are used to define a panel will have a triple representation as follows. 1. As a node in the initial 3D stylised panel. 2. As a node on the 2D flattening of the panel. 3. As a node in the drape simulation of the panel. . Pattern flattening Some attempts have been made to provide software to generate 2D patterns for garments [2,3]. However, these have met with limited success because of the prerequisite that a full 3D specification must previously exist in order for a 2D pattern to be ,there has to be an intelligent examination of the garment specification to establish how critical the pattern flattening process should be in conforming to the original 3D surface. The authors propose that the garment specification should be intelligently partitioned into fit and drape areas. The primary indicator of whether an area of a garment is in either of these two categories is the offset with respect to underlying mannequin and the degree to which the garment is forced to be constrained to this offset. Depending on this partitioning, the flattening process would flatten fitted areas differently from draped areas. Another influential factor would be the material characteristics of the fabric involved. This is made more difficult by the anisotropic nature of most fabrics due to their woven or knitted construction. Finally, it is important that 2D flattening specifications do not simply consist of a 2D needs to be a full interior