Provides access to members that control Display Transformation.

#### Product Availability

#### When To Use

Use **IDisplayTransformation** for converting coordinates between real-world and device space and back. To prepare a transform for use, follow these steps:

- Set the full map extent with the Bounds property
- Set the visible map extent (zoom rectangle) with the VisibleBounds property
- Set the output area of the device using the DeviceFrame property
- Set the resolution of the output device using the Resolution property

The transform is based on the ratio between the VisibleBounds and the DeviceFrame. Normally the DeviceFrame is simply the full extent of the device with the origin equal to 0,0.

The transform object calculates the FittedBounds automatically and this is the visible map extent adjusted to fit the device.

#### Members

Description |
||
---|---|---|

Bounds | Full extent in world coordinates. | |

ConstrainedBounds | Intersection of Bounds and VisibleBounds. | |

DeviceFrame | Visible extent in device coordinates. | |

FittedBounds | Device frame in world coordinates. | |

FromMapPoint | Calculates device coordinates corresponding to the map point. | |

FromPoints | Calculates a map distance corresponding to a point (1/72) distance. | |

ReferenceScale | Reference scale for computing scaled symbol sizes. | |

Resolution | Resolution of the device in dots (pixels) per inch. | |

Rotation | Rotation angle in degrees. | |

ScaleRatio | Scale between FittedBounds and DeviceFrame. | |

SpatialReference | Current spatial reference. | |

SuppressEvents | Indicates if transformation object suppresses events. | |

ToMapPoint | Calculates a point in map coordinates corresponding to the device point. | |

ToPoints | Calculates a distance in points (1/72 inch) corresponding to the map distance. | |

TransformCoords | Transforms a set of points or measurements from device to world space or vice versa. Use the flags specified by esriDisplayTransformEnum. | |

TransformMeasuresFF | Transforms floating point measures to floating point measures (or do the inverse). | |

TransformMeasuresFI | Transforms floating point measures to integer measures (or do the inverse). | |

TransformMeasuresIF | Transforms integer measures to floating point measures (or do the inverse). | |

TransformMeasuresII | Transforms integer measures to integer measures (or do the inverse). | |

TransformPointsFF | Transforms floating point points to floating point points (or do the inverse). | |

TransformPointsFI | Transforms floating point points to integer points (or do the inverse). | |

TransformPointsIF | Transforms integer points to floating point points (or do the inverse). | |

TransformPointsII | Transforms integer points to integer points (or do the inverse). | |

TransformRect | Transforms a rectangle from device to world space or vice versa. Use the flags specified by esriDisplayTransformEnum. | |

Units | Units used by world coordinates. | |

VisibleBounds | Visible extent in world coordinates. | |

ZoomResolution | Indicates if resolution is tied to visible bounds. If true, zooming in magnifies contents (i.e., zoom in on page). |

#### Inherited Interfaces

Interfaces | Description |
---|---|

ITransformation | Provides access to members that apply a function (or its inverse) to a set of points or measures. The suffix of each method indicates the type of parameters operated on. |

#### CoClasses that implement IDisplayTransformation

CoClasses and Classes | Description |
---|---|

DisplayTransformation | Display transformation class for converting from world to device units. |

#### Remarks

Obtain an **IDisplayTransformation **reference to the **DisplayTransformation** object from **IDisplay::DisplayTransformation**. Because **IScreenDisplay** inherits from **IDisplay**, you can also use **IScreenDisplay::DisplayTransformation**.

Each DisplayTransformation manages a coordinate system object such as a **GeographicCoordinateSystem** or **ProjectedCoordinateSystem**. Obtain a reference to the display's coordinate system object using **IDisplayTransformation::SpatialReference**.

The **DisplayTransformation **of a **PageLayout **object does not have a spatial reference and translates between device units and page units.