Graph IDE ► 3D Data Graphics ► Volume
A Volume is a sequence of density values (from 0 to 1) that are mapped to colors via a color mapping with each density appearing as a cube on a regular 3D grid. The number of density values must be equal to the grid specifications (number of x, y, z cells). The figure below shows examples of 3D volume graphics.
Standard Operations
To create a volume bring forward the Graphic Selector, click the volume factory cell and then mouse down on a Graphic View and drag the cursor to another point. The initial and final cursor locations define the boundary of a predefined volume graphic.
The normal way to modify the density of a volume is through the volume's Inspector Editor's data entry field. That field accepts a whitespace sequence of density values. The number of density values must be equal to the grid specifications (number of x, y, z cells).
For information on entering data points see Export And Import Data: Raw Data Points. The Volume conforms to the Color Map standards where the color map gradient is one of:
| Color Mapping Type (Applies to Markers Only) | |
| No Color Map | IGNORE: This has limited applicability. The color map is off. This makes most sense while just drawing the stroke so that only the trajectory appears. |
| False Color | IGNORE: This has limited applicability. The color is mapped from arbitrary independent values. Because there is no way to specify another independent value set this UI implementation maps from the z-values of the data. Programs can map from another basis. |
| Density-Value | The color is mapped from the density-value of the data points. |
| Distance | IGNORE: This has limited applicability. The color is mapped from a value related by the distance of the data point to the viewer. The distance is normalized so that the nearest and farthest points of data define the distance extremum. |
Data Editor
The Data Editor for the Point Map is shown below.
Table
Apply : Once the grid values have been entered then click the Apply button to redefine the grid.
Table controls are described in the Tables section.
The rows represent density of a particular cell and must be a value between zero and one.
Grid Values
The data table does not specify grid parameters, it only specifies amplitude values. That is because a volume map is on a regular grid. A regular grid is defined by the nine values described below.
Dimension : The number of cells in the x, y and z dimension, aka: The dimensions of the matrix of values. The product of x, y and z dimensions should equal the number of rows in the table.
Minimum : The x, y and z minimum of the grid.
Maximum : The x, y and z maximum of the grid.
Graphics Editor
The Graphics Editor for the Point Map is shown below.
Common Controls
Controls common to all graphics are described in the Graphics section.
Color Map Attributes
The color map is further described in the Color Map section.
Graph : Shows a graph of the color map.
Function : Select this to set the color map function. Typically it is set to linear.
Start Color : Defines the start Color of the color map.
End Color : Defines the end Color of the color map.
Number : Defines the number of samples in the color map.
Solid Attributes
Volume Draw State : If checked then the volume is drawn.
Fill Color : Defines the fill Color for the volume. This is normally overridden by the Color Map.
Grid Attributes
Grid attributes are controlled by the normal stroke controls defined in the Graphics section.
Fill Editor
The Fill Editor for the 3D Volume graphic is shown below.
Fill attributes is a false color table of RGBA components, one for each cell. These can be overridden by the Color Interpretation setting and that setting must be False Color Map in order for the elements of this table to take effect.
Table
Table controls are described in the Tables section.
The rows represent a segment color values. While in Atomic mode, the cell represents a rgba value and while in component mode the cell represents either single r, g, b and a. Hence, in atomic mode there is one column while in component mode there are four columns.
Note that if the Data sequence is changed then the Fill sequence will not change.