The Component tab appears in the Info pane when the focus is on an opened window. It displays information relevant to that component, such as the projection (coordinate system), for the active window and for the active layer within that window. Clicking on a component shown in the Component tab will switch to that component in the Project pane.
The upper part of the pane reports information for the active window, such as a map window. The lower part of the pane reports information for the active layer in that window. The information displayed will vary with the type of component. For example, the Component pane for images will show the size of the image in pixels and also the size of each individual pixel in the units of measure used by the coordinate system for that image.
Coordinate systems are reported in black color text if the coordinate system has already been correctly assigned, or in red color text if the initial coordinate system has not yet been assigned. The records number reports the total number of records in the drawing (objects) or image (tiles).
Move to Previous / Move to Next - Click to pick the previous record or the next record. Will be enabled if an object or record has been picked with an Alt-click, and normally used mainly with the Values tab or the Coordinates tab. This is useful for data sets where records are in order. When records are not ordered in a table, as usually is the case in enterprise class databases, these buttons will be used mainly to step through relatively small selections, with the
Selected - Move only within selected records. When enabled (only possible if there is a selection), constrains Previous and Next motion to the previous selected record or to the next selected record.
Go - Go to the current object or record in the opened window.
Coordinate System Picker - Manage the coordinate system. Coordinate systems are reported in black color text if the coordinate system has already been correctly assigned, or in red color text if the initial coordinate system has not yet been assigned.
Description - Open the Description dialog to enable entering or editing a description.
Press to apply any changes, such as changes in the Description.
Illustrations in this topic may be reduced in size to allow more compact documentation display. Undocked panes can be resized to be larger or smaller, but not as small as the smallest illustrations that may appear.
When a map has the focus the Component tab will report projection information for the map as well as for the active layer within that map. In the illustration below the buildings layer is the active layer in the map.
The tab displays the active layer component, the table used by that component, the geometry field or tile field used, and the spatial index used. The number of records reported will report the number of rows in the source table (including those with NULLs for the geometry or tile field). The Info pane will report the text field used for labels.
Tech tip: Clicking on any component shown in the Component display will highlight that component in the Project pane opening folders as necessary in the Project pane to show the component.
When a drawing has the focus the Component tab will report projection information for the drawing as well as for the active layer within that drawing, if the drawing has more than one layer. When a drawing window has only one layer, the same component is reported in both the upper and lower parts of the pane.
The number of records reported for a drawing is the number of objects, since each object is one record in the drawing's table.
When a table has the focus the Component tab will report the number of records in the table.
When an image has the focus the Component tab will report projection information for the image as well as for the active layer within that image, if the image has more than one layer.
The Component pane for images will show the size of the image in pixels and also the size of each individual pixel in the units of measure used by the coordinate system for that image.
The number of records in an image is the number of tiles. The info pane will provide the size in pixels for each tile as well as the data type for each pixel. A Tile size of 128x128 means each tile is 128 pixels wide by 128 pixels high, for a total of 16,284 pixels per tile. A data type of float32 indicates each pixel has one channel, that is, only one value per pixel with a float32 data type used for the value. A three channel image will have an x3 data type, such as uint8x3, where each of the three values per pixel is a uint8 data type.
When the focus is on a text component such as a Comments, Location, Query, or Script component, the Info pane will report the number of lines of text. For scripts, the Info pane will report the language used by the script.
When a layout has the focus the Component tab will report the page size of the layout as well as the description.
See the Layouts: Info Pane topic for many examples.
The Component tab in the Info pane is our primary interface for seeing and changing projections, that is, the coordinate systems assigned to components, and to edit those coordinate systems. In Manifold, the terms projection and coordinate system are synonyms and are used interchangeably. The Component tab tells us at a glance the coordinate system (projection) used by a component, and it also tells us at a glance if that coordinate system has not yet been correctly assigned.
When a format or data source has specified the coordinate system to use, Manifold displays the coordinate system in black color. If the coordinate system is shown in red color, that tells us the coordinate system has not been correctly assigned. In that case, we must click the coordinate system picker button and choose Assign Initial Coordinate System to assign the coordinate system that should be used.
Black projection name - Indicates the coordinate system has been assigned. Modern GIS formats will automatically specify the coordinate system to be used when we import a drawing or image from such a format. They will appear in the right places in maps with other layers, we can re-project them if we like and so on.
Red projection name - Indicates the coordinate system must be manually assigned before that data can be used. Older GIS formats or non-spatial formats, such as CAD formats, often will not correctly specify the coordinate system used by their data. In such cases, the default coordinate system, WGS 84 / Pseudo-Mercator (EPSG:3857) will be assigned as a placeholder, and red text is a warning that the correct coordinate system must be assigned before any further use of the data.
We use the Component tab for three key activities involving coordinate systems:
Assign Initial Coordinate System - If a component is imported from a format that fails to specify the coordinate system it should use, we must do so manually. Until we assign the initial coordinate system to use, the Component tab will use red text for the read-out. Once we assign the initial coordinate system the read-out will switch to black text. This command should only be used once, immediately after initial import or linking of a component. For a step-by-step illustrated example using the Assign Initial Coordinate System command, see the Example: Assign Initial Coordinate System topic.
Repair Initial Coordinate System - If people and software never made mistakes we would not need this option. Sometimes a component is imported from a format that incorrectly specifies the coordinate system it should use, and we must manually change that initial setting to the correct coordinate system. At other times, we might have used Assign Initial Coordinate System to specify the initial setting, but we made a mistake and specified the wrong projection. This option allows us to repair such errors by specifying the correct initial coordinate system.
Reproject Component - This is the routine command we use to re-project data into whatever projection we want. Suppose, for example, we import data that is in Latitude / Longitude format but we want it to be in pseudo-Mercator or some other coordinate system. This option allows us to re-project the data to the new coordinate system.
To assign, repair, or change a projection, click on the coordinate picker button.
The Component tab provides room for a text Description for the context component. The description can contain whatever text we want, edited by clicking the [...] browse button. Adding text using the browse button will cause the description text to appear.
If we start with a component that has no description, we can press the browse button to pop open an editing window. We enter the description desired and then press OK.
The new description appears in the Info pane. Descriptions in the Info pane will be word-wrapped to fit into the available width of the pane.
The text is in the Description property for the component, which we can create and edit manually in the Properties dialog for that component (right-click the component in the Project pane and choose Properties).
Like all properties for components, the Description property appears in the mfd_meta table, seen above and selected for emphasis. We can manipulate descriptions in the mfd_meta table by manually editing the table, or editing the table programmatically or using SQL.
When a component has a Description, hovering the mouse over that component will show the first line of the description as a tool tip.
When working with undocked panes, if we have the Info pane sized to minimum width, there may not be enough horizontal room to display the full numbers and units of the Pixel size values.
For example, in the illustration above the pixel size numbers for an image imported from ECW are not exactly 0.5 by 0.5, apparently because the image was at some point reprojected into the coordinate system now being used, which resulted in a slight change in pixel size.
Seeing the full numbers is easy: we simply widen the pane by dragging the right border of the pane to make it wider.
The result provides plenty of room to see the full numbers, as well as the units of measure used, in this case a custom value for US feet.
Clicking on a component shown in the Component tab will highlight that component in the Project pane, opening folders as necessary in the Project pane to show the component.
Info Pane: Values
Info Pane: Coordinates
Info Pane: Style
Info Pane: Related
Info Pane: Pixels
Info Pane: Position
Info Pane and Images
Layouts: Info Pane
User Interface Basics
Assign Initial Coordinate System
Repair Initial Coordinate System
Example: Edit Coordinates While Creating an Object - When creating an object in a map using a tool such as Create Area, right in the middle of the process we can edit coordinates in the Info pane Coordinates tab. This example shows the step by step process.
Example: Edit Attributes and Move a Point - We look at the attributes for a point in a drawing layer and edit one of the attributes using a more expanded Edit dialog. We then move the point to a new location. Easy!
Example: Edit Attributes, Larger Text, IME for Asian Languages - A tour showing how to edit attributes in a drawing using the Info pane Values tab and the expanded Edit dialog, including advanced Unicode facilities and use of the built in Input Method Editor (IME) to input text in Japanese language.
Example: Assign Initial Coordinate System - Use the Info pane to manually assign an initial coordinate system when importing from a format that does not specify the coordinate system.
Example: Change Projection of an Image - Use the Reproject Component command to change the projection of an image, raster data showing terrain elevations in a region of Florida, from Latitude / Longitude to Orthographic centered on Florida.
Example: Create Parcels from Traverse Files - Traverse files using ESRI traverse file format are widely used by surveyors and government organizations in the US to define parcels and lines by describing a sequence of directions, distances and curves from a starting point. Manifold automatically handles both tangent and non-tangent curves in ESRI traverse file format as well as the full variety of options used to specify angles, distances and curves. This video shows how it's easy to create a parcel from a traverse file.