mpax5.0比mapx4.51多了些什么功能？

Layer Packing: Packing the data contained in a layer will remove deleted records and will rebuild the index and graphics files. To implement this feature, two methods have been added to the Layer object.They are:

Layer.Pack method (Layer object)
Layer.SupportsPack method (Layer object)

Save Layer as native MapInfo table with .mdb data file: When creating a new table, MapX offers a choice between MapInfo Native and MS Access format. Additionally, you have the choice of which version of Access MDB MapX creates.
A new permanent table can be created by specifying a LayerInfo.Type (see TableStorageType & AccessVersion on the parameter table of LayerInfo Object under miLayerInfoTypeNewTable).

Cache Performance Improvements for Remote Database connectivity: Enhancements to MapX抯 caching ability have been made by expanding the Cache parameter of the LayerInfo object, the addition of three new objects and three methods connecting them to the Layer object. Specifically, the Cache dataset is used to cache records from a remote database dataset to prevent return trips the remote database server for data that MapX recently fetched. Previously in MapX, the cache maintained one MBR constraint for each layer. Now, a user/programmer has the ability to dictate what is allowed to be stored in cache, how much is stored, and when it should be removed. Please refer to the following for more specific information:

LayerInfo Object
BoundsConstraint object
FeaturesConstraint object
AllFeaturesConstraint object
Layer.CreateBoundsConstraint method (Layer Object)
Layer.CreateFeaturesConstraint method (Layer Object)
Layer.CreateAllFeaturesConstraint method (Layer Object)

Double Stereographic Projection: For Double Stereographic projection the ellipsoidal data is first mapped conformally on a conformal sphere. Then, a second conformal mapping of the spherical data to the plane completes the process. This projection is used for Prince Edward Island and New Brunswick in Canada. Please refer to, Summary of Parameters Used by Coordinate Systems.

Dynamic Selection for Radius and Rectangle Selection Tools: In the Map object, you will find a new property called Map.DynamicSelectionSupport property (Map object). Previously in MapX, when you dragged your selected tool cursor and released the mouse button, MapX highlighted all objects within the rubber band circle you drew. With Dynamic selection mode turned on, you can select objects as you are dragging the mouse (i.e. without having to release the mouse buttons so you can see your selection with out having actually made it). This mode is optional and will be enabled by setting this boolean property to true or false. It will affect only rectangle and radius selection tools.

Labeling Enhancements: Previously in MapX, a programmer had control over labels on a per layer basis, but not on an individual label basis. Until now, there was no ability to customize the appearance and content of individual labels. With the addition of the Label object and collection, the LabelChanged Event, AND two new properties in the LabelProperties object, MapInfo has extended this functionality to MapX programmers.

MapX programmers can also allow users to edit labels manually with the MapX Select tool. The Map.EditableLabels property controls whether the user can select and move labels with the stock select tool. (see Map.EditableLabels property (Map object)

The new features are:

LabelProperties.LabelPartialObjects property (LabelProperties object): The PartialSegment property has been deprecated (but will be supported for backward compatibility) and replaced with the new property, LabelProperties.LabelPartialObjects. Its behavior applies to all map objects (with the exception of points) rather than just polylines. Therefore, if two dimensional GeoObjects are being labeled but their centroids are outside the map, MapX will still label them. The behavior is the same when labelling polylines.

LabelProperties.LabelAlong property (LabelProperties object): The LabelAlong property replaces the old Parallel property, which we still support but have deprecated to a hidden property. The parallel property dictated whether labels on lines and polylines are not rotated or are drawn at the same angle as the line or polyline segment to which they are anchored. With the LabelAlong property, you may indicate that the label will follow the contour of what it is labeling if the object being labeled is a polyline. LabelAlong has three states, represented by constants. (See LabelAlongConstants). For objects other than polylines, if the property is set to miLabelAlongMultiSegment, the property is ignored (i.e., for point and region objects). For line objects, if the property is set to miLabelAlongMultiSegment, automatic labels are drawn as if the property is set to miLabelAlongParallel.

Label object and Labels collection: There is a new object accessed through the Layer object (see the new property Layer.Labels property (Layer object)) that represents a collection of labels.The collection is the set of labels that are currently drawn AND those that were edited either through the user interface or programatically. Please refer to the properties associated with the Label object.
LabelChanged Event: MapX fires this event whenever a label is about to be modified, hidden (labels cannot really be deleted), marked as hidden, or unhidden. The MapX programmer has the opportunity to prevent the operation by setting the EnableDefault value to False.

Military Grid Reference System: MapX now includes the ability to convert to and from MGRFS using the following methods of the Map object.

Map.MilitraryGridReferenceFromPoint method (Map object)
Map.MilitaryGridReferenceToPointV method (Map object)
Map.MilitaryGridReferenceToPoint method (Map object)

Snap to Node: When this feature is enabled, if there are any nodes present in the rectangle around the current mouse position, the feature snaps to the closest node to the centroid of the rectangle and draws cross hair. This mode can be turned on under all tools. Please refer to the following new Map object properties and method:

Map.SnapToNodeSupport property (Map object)
Map.SnapTolerance property (Map object)

JPEG2000 support: This Raster format has been added to this list of Raster formats MapX supports.

Unicode Support: MapX is now a unicode application.

Mutipoint and Collection objects: MapInfo has added support for two new GeoObject types in MapX 5.0 - Multipoint and Collection objects. A Multipoint is a single object consisting of a number of points. The Multipoint object corresponds to a single record in a table and all the points within the object have the same symbol. A Collection object consists of a number of objects that have been combined into a single object. The Collection object may contain a mixture of points, polylines, and polygons.

Six new Feature object properties were added for Multipoint and Collection objects in order to support these new GeoObject types:

Feature.HasMultipoint property (Feature object)
Feature.HasPolyline property (Feature object)
Feature.HasRegion property (Feature object)
Feature.Multipoint property (Feature object)
Feature.Polyline property (Feature object)
Feature.Region property (Feature object)

FeatureFactory object now has two new methods:

FeatureFactory.CreateMultipoint method (FeatureFactory object)
FeatureFactory.CreateCollectionFeature method (FeatureFactory object)

Label Thematics Support: This feature allows a MapX developer to add themes to a layer dataset to modify the layer抯 label display characteristics (i.e. a label抯 textual style). Please refer to Label Thematics for additional information and ThemeTypeConstants for the new enumerated constant values.

Coordinate System Updates: Five additional coordinate systems have been added to MapX. (See Summary of Parameters Used by Coordinate Systems) The new projections are:

Mercator Regional
Polyconic
Cassini - Soldner
*Azimuthal Equidistant (now, all origin latitudes)
*Lambert Azimuthal Equal-Area (now, all origin latitudes)

Please refer to the CoordSysTypeConstants for the new enumerated constant values.

Note: *The Azimuthal Equidistant and Lambert Azimuthal Equal-Area projection existed previously in MapX, but with only with pole aspects.

Oracle Call Interface(OCI) Data Source Support: MapX can use OCI to retrieve data from an Oracle data source. You need to specify the connection string and the SQL string to execute by using the OCIQueryInfo Object.

For additional information, see OCIQueryInfo object.

Points and Parts Performance Optimization: With the addition of three additional methods of the Points collection, MapX developers can quickly derive the XY coordinates of any given point. These methods and their corresponding pages in the developer guide are:

Points.GetXY method (Points collection)
Points.X method (Points collection)
Points.Y method (Points collection)
Points.GetXYV method (Points collection)

State Object: This allows you to save the current state of an item, such as an object or variable, so that you can restore the item back to that state at a later time. You can save and restore MapX objects or variables (e.g. a String or Boolean.)

For additional information, see State Object.

Grid and Raster Handlers: MapX includes support for additional raster and grid file formats.

These raster formats include:

MrSID (*.sid) from Lizard Tech
ECW (*.ecw) from ER Mapper
Vertical Mapper Continuous Grids (*.grd) from Northwood Technologies
Vertical Mapper Classified Grids (*.grc) from Northwood Technologies

Grid formats include:

USGS DEM (*.dem)
GTOPO30 (*.dem)
DTED (*.dt0, *.dt1, *.dt2)
Vertical Mapper Continuous Grids (*.grd) from Marconie (Formarly Northwood)

These raster and grid handlers provide support for displaying files in additional formats. These handlers are in addition to the existing handlers that have been included in previous versions.

Translucent Rasters Images: A translucent image can be seen through. This allows raster images to be placed on top of other layers, while the underlying layers are still partially visible. MapXtreme supports translucency for raster tables that have translucency enabled using MapInfo Professional 6.5.