The Surface Properties Dialog can be accessed by selecting a Surface (in a Photograph , 3D Viewer or Surface Table) and using the “Properties of Selected” tool, the “Properties of Selected…” item on the ribbon toolbar’s View Tab, or the right-click menu item “Properties of Selected…”.
The dialog will display information from one or more Surfaces. If the information is the same for all selected items, then the information will appear in the dialog. If the information differs then the field in the dialog will be blank or will be a shaded check box. Even if multiple Surfaces are selected a property value can still be modified. When the Apply or OK button is pressed, all the selected items will be changed to that value. The number in brackets shows how many objects have been selected..
All Surfaces have these properties:
• a unique identifier number called an ID – you can renumber your surfaces using the Renumber Dialog,
• a “smoothed” flag – when set the surface will appear smooth shaded in the 3D Viewer (and some export formats),
• a “Compute 3D shape” flag – when set the surface will be computed in 3D (if possible). Default is on. Uncheck this to stop a surface from having a 3D representation without getting rid of its defining objects, etc.
• a Material, and
• a Layer.
All surfaces except Silhouettes also have these properties
• a “double-sided” flag – when set the Surface will be visible from both sides in the 3D Viewer (and in some export formats),
• Four extend percentages (displayed in the Extend property), and
• Trim/hole settings (displayed in the Trim & holes property).
Path & Triangle:
• a “shape calculation” setting – when set to “Triangulation based” the Surface will be calculated using planar triangulation, when set to “NURBS based” the Surface will calculate as a NURBS Surface.
• A “smoothing group” – an integer value between 0 and 255 the defines which group this path surface belongs too. All path surfaces (which includes triangles (which are 3 sided paths)) in the same smoothing group and share an edge are smooth shaded in the 3d Viewer. Some export formats (notably 3DS and OBJ) also support smoothing groups. A smoothing group of 0 means this surface belongs to no group and hence is not smoothed against any other surface.
• Path Surface’s can optionally acquire their textures based on the mark’s position in a photo as opposed to the projected position. The “Material texture location” buttons on the Path Surface Properties section controls this. Using the mark’s location allows you to ‘tweak’ some cases where the projected location does not match the image exactly. (E.g. bits of sky mapping to the peak of a roof). This setting only applies to path surfaces defined by marked points and not to path surfaces defined by curves or edges.
Lofts:
• a “closed” flag – when set the Surface will start and end at the same object.
Revolutions:
• a “Degrees of Revolution” setting. Controls how far around the axis of revolution the surface should go.
Silhouettes:
• a “silhouette calculated using” setting – when set to “Polygons” the Surface will be calculated using polygons, when set to “NURBS” the Surface will calculate using NURBS. The NURBS form is slower but more accurate.
• silhouettes have a tolerance setting which controls the silhouette surface intersection algorithm. Increasing the tolerance results in a simpler but more robust silhouette surface.
• silhouettes have an optional user name.
Fit NURBS Surface to selected points:
• Max Spans U and V – Controls how well the surface fits to a set of points.
Properties of surfaces can be viewed using several features in the PhotoModeler user interface, including the Properties of Selected Dialog, Properties Pane, Surface Table and the Status Bars. Also note that the Measurements Pane shows various data about one or more selected surfaces.