Understanding the layer draw order in 3D
The order in which layers are drawn directly impacts which data is shown when two or more layers occupy the same 3D space. You need to be aware of the layer drawing priority when creating a 3D view to ensure that the most appropriate data is shown. For example, you will probably want a high-resolution aerial photograph to be rendered with a higher priority than a low-resolution satellite image.
The drawing priority of layers becomes particularly important in these circumstances:
- When using partial transparency
- Multiple layers sharing the same 3D location
- Multiple layers draped on the same surface
In ArcMap, the layer draw order begins at the bottom of the table of contents and moves upward. A layer at the top of the table of contents will therefore obscure any layers below it. This methodology has been partially transferred into ArcGlobe but is not true for all layer types and is not applicable at all in ArcScene.
Draped layers in ArcGlobe are the most similar to ArcMap. These layers use their relative position within the Draped category of the table of contents to define their draw order. As with ArcMap, layers are drawn from the bottom of the list to the top, so layers higher in the list will obscure those below them. Layers should be reordered within the Draped category to adjust their drawing priority. When new draped data is added to ArcGlobe, the application will attempt to automatically place the new layer into the best location within the Draped category.
Floating layers in ArcGlobe have their drawing order based on their position relative to the globe surface, which has a representative draw order position of 0. Floating layers that are above the surface should have a positive drawing priority value, such as +1. Floating layers below the surface should have a negative drawing priority value, such as -1. The absolute value of the drawing priority should reflect the relative position of the floating layer from the surface of the globe.
In ArcScene, both floating layers and draped layers use a drawing priority layer property to define their draw order. The value can range between 1 and 10, where 1 is the highest drawing priority. If two or more layers share the same 3D space, the layer with a drawing priority of 1 will obscure the layers with a drawing priority of 2 or higher.
Learn more about layer drawing priority in ArcGlobe
Learn more about layer drawing priority in ArcScene