【正文】 Table The name of the table that contains the data to analyze. When specifying SQL table names, use fully qualified table names, that is, the owner of the table, followed by a period (.), followed by the table name. Key Column The name of the theme table column to use as the primary key. The default is the key column that you specified on the Data Sources tab. Note that if the spatial data for the layer es from a SDF, the 。 Chapter 4: Working with Map Layers in Autodesk MapGuide Author 25 Figure : Theme Setting dialog box. 下表類出了在 Theme Setting 對(duì)話框中的每一個(gè)設(shè)置： Data Source SQL 數(shù)據(jù)源的名字，以此 MapGuide Server 可以生成主題。在 Theme Setting 對(duì)話框中可以定義主題應(yīng)用。 主題顯示 Theme 部分是用來生成或改變?cè)诋?dāng)前地圖圖層上特征的顯示主題，例如，對(duì)于一個(gè)零售商店位置的點(diǎn)圖層來說，典型的主題就是用不同的符號(hào)來顯示不同類型的零售商店。此對(duì)話框的其余部分決定著圖層在比例范圍內(nèi)時(shí)如何顯示在地圖窗口中的。如圖 。 Map Server URL 指定 MapGuide 服務(wù)器中能夠提供數(shù)據(jù)的完整 URL。這個(gè)控件只有在選中了 Link To Secondary Table 單選框后才生效。這可以使用戶只要單擊某個(gè)特征就可以跳到一個(gè)網(wǎng)夜上去。這個(gè)控件只有在選中了 Link To Secondary Table 單選框后才生效。要生成多行地圖提示，可以在兩個(gè)字段名中間加入換行符（ \n）， chr(10) 或任 何 ASCII 代碼。 Name Column 指定包含每個(gè)地圖特征名的字段。 Name Source 指定是否從特征表或從第二表格中獲得特征名。 Select Secondary Table 單擊此按鈕可以選擇第二表格。第二表格也許會(huì)包含 lookup 表格或者用來過濾空間信息（例如土地應(yīng)用和人口）的字段。 Map Server URL 指定 MapGuide 服務(wù)器中能夠提供數(shù)據(jù)的完整 URL?？梢灾付ㄏ旅骖愋偷娜我庖粋€(gè)作為關(guān)鍵字段的類型： String, Integer, Small Integer, Float, Double, Date, Time, Timestamp, Boolean, Unsigned Integer, Unsigned Small Integer, Numeric 或者 Decimal。如果是通過瀏覽按鈕輸入的字段名， Autodesk MapGuide Author 會(huì)自動(dòng)確定類型。 Key Column 指定包含每個(gè)地圖特征關(guān)鍵字段的名字。 Data Source 指定 SDP 數(shù)據(jù)源的名字。 下表列出的是 SDP Data Source 選項(xiàng)卡中的功能： Draw Features From 指定包含正在應(yīng)用圖層中特征的數(shù)據(jù)源的類型，或者是空間數(shù)據(jù)提供者（ SDP）數(shù)據(jù)源，或者是 OLE DB 數(shù)據(jù)源。進(jìn)入瀏覽界面后，就可以按 Refresh 按Chapter 4: Working with Map Layers in Autodesk MapGuide Author 22 鈕來刷新在 Autodesk MapGuide Server 上的文件列表或數(shù)據(jù)源。 Features that are created with data from a SQL table are linked to attribute data records in the SQL table through their feature keys. Features that are created with data from a SDF can also be linked to attribute data records in a SQL table and the internal keys are shown. A feature key is used to link to the correct record in the SQL table. Autodesk MapGuide Author 在數(shù)據(jù)源部分（以及在其它的對(duì)話框中）提供了瀏覽按鈕 來使用戶可以快速地確定預(yù)先完成的設(shè)置，例如已經(jīng)建立的數(shù)據(jù)源，特征表格，關(guān)鍵字段名，等等。 political boundaries, etc.). Autodesk MapGuide Author also enables you to prioritize map layers. Layers are drawn in order of increasing priority. For instance, the layer with the lowest priority is drawn first, the next higher priority is drawn next, and so on until the layer with the highest priority is drawn last, on top of all other layers. This is reflected in the legend, where the layer with the lowest priority is at the bottom of the list, and the layer with the highest priority is at the top of the list. Layer priorities range in value from 0 to 100, and can include decimal values, thus enabling you to easily add new layers to a map between existing layers. Data Sources The Data Sources tab enables you to specify or change the source of the data being represented in MapGuide (Figure ). Figure Map Layer Properties dialog box: SDP Data Sources tab 每一個(gè)地圖特征都有一個(gè)名字，一個(gè)唯一的 key 值，有時(shí)還有一個(gè) URL 連接，可以用來連接到 Web 上的另一個(gè)地圖或文檔。 Map layers and Display Ranges can be set. By making a map layer selectable, the client can interact with the map by creating reports or by using another feature of Autodesk MapGuide. Autodesk MapGuide Author enables you to make map layers dynamic or static. When a map layer is dynamic, layer data is downloaded from the Autodesk MapGuide Server on demand. Only layer attributes (color, style, symbol, etc.), not data, are stored in the Map Window File (MWF), thus minimizing its size. Dynamic layers are most appropriate for medium to large data sets that may change over time. When a map layer is static, a snapshot copy of the layer for the entire map window is taken from the Autodesk MapGuide Server and embedded in the MWF. However, if the map39。數(shù)目越大圖層的優(yōu)先級(jí)越高。而靜態(tài)的圖層會(huì)下載該圖層的所有數(shù)據(jù)，并把數(shù)據(jù)嵌入到MWF 文件中。 (2) 要生成地圖特征的報(bào)告。 General 在 General 選項(xiàng)卡上，可以改變所選圖層的名字、可見性、類型、優(yōu)先級(jí)、可選性和在 MapGuide Viewer 圖例中的可見性。 ? 生成并修改主題圖層。 ? 生成具有下面屬性的圖層：點(diǎn)，多段線，多邊形，文本和光柵。 Each layer will symbolize a different feature type, and you will explore the features available in Autodesk MapGuide Author for controlling how layer features are displayed on the map. Objectives After pleting this chapter, you will be able to: ? 在 Autodesk MapGuide Author Preferences 中建立一個(gè)默認(rèn)的地圖服務(wù)器 URL 地址。默認(rèn)的情況下，用來描述地圖特征的數(shù)據(jù)是不會(huì)保存在 MWF 文件中的，但是數(shù)據(jù)的是由 Autodesk MapGuide 服務(wù)器的安 全性設(shè)置來維護(hù)的。 ? 地圖窗口的中心和尺寸設(shè)置是將要在客戶端顯示的地圖數(shù)據(jù)的范圍和極限。 Chapter 4: Working with Map Layers in Autodesk MapGuide Author 17 ? 每一個(gè) MWF 文件都具有全局的屬性，包括：地圖名、背景顏色、尺寸和應(yīng)用的坐標(biāo)系統(tǒng)等。 13. 應(yīng)用 Zoom 和 Pan 命調(diào)整地圖到更好的位置 ，然后用 Take Center and Size from Current Zoom 按鈕來再一次設(shè)置地圖。單擊 Change 按鈕來打開 Change Map Window Coordinate System 對(duì)話框。通過此項(xiàng)操作就可以從單前的視圖中捕獲到緯度、精度、寬度和高度值。 單擊 OK，這是注意這個(gè)名字現(xiàn)在顯示在 Autodesk MapGuide Author 的標(biāo)題欄上。還可以用 Zoom 和 Pan 命令來調(diào)整當(dāng) 前的視區(qū)。 6. 把地圖區(qū)域定位在亞洲。 4. 雙擊 World Countries 圖層打開 Map Layer Properties 對(duì)話框 , 然后單擊 Data Sources 選項(xiàng)卡 (Figure ). 設(shè)置 Map server URL，可以通過改變 文件的此設(shè)置來一次性改變圖層的 URL 設(shè)置。s curved surface and drawing them on a flat map. Map projections refer to the techniques cartographers and mathematicians have devised over the centuries to depict all or part of a threedimensional, roughly spherical surface (like the earth) on a twodimensional, flat surface (like this page) with minimal distortion. Traditionally, cartographers did not routinely change from one projection to another, largely because of the plex mathematical calculations required. However, with the advent of digital mapping, changing projections has bee both essential and easier. It is important to annotate all maps with the projection and related parameters of a digitized map. This information is required for calculations with global coordinate systems. Chapter 4: Working with Map Layers in Autodesk MapGuide Author 15