| Shading Options Plane Shading Other Settings Isolating Areas Using the Clip Box Point cloud shading options are accessed under the Point Cloud | Shader tab of the Settings box.
The following options are available:
Show RGB Sets the global RGB filter. Switching this option off prevents any RGB data being shown. Show Intensity Sets the global Intensity filter. Switching this option off prevents any Intensity data being shown. Blending This effects the display of point clouds where both Intensity and RGB data for points are available. Showing both
values blends the two shading models. This may be used to enhance the visual quality of the data. Intensity Ramp Sets the colour ramp that is used to display intensity values. Brightness Sets the offset for the intensity values. This is analogous to brightness in a greyscale image. Contrast Sets the range over which the intensity values are distributed or scaled. This is analogous to contrast in a greyscale image. Point Cloud Lighting If checked applies lighting to point clouds. This can greatly enhance the clarity of the data showing detail that is otherwise hidden. Lighting is only enabled for point clouds with Normal data. This data is either imported from the source file or
generated on import. see Importing Point Clouds for more information on generating normals. The Point Cloud Lighting option requires support for the ARB Vertex Shader extension in your graphics hardware. Material Quality This option only affects points when lighting is in use and determines the specular and diffuse quality of the material being used. This feature is named 'Height Shading' in version 1.5-1.52.
Point cloud plane shading options are accessed under the Point Cloud | PlaneShader tab of the Settings box.
Plane shading shades points according to their distance from a plane. By default the Z plane is used. This is very useful
for visualising aerial LIDAR data, especially when intensity or RGB values are not available. New in version 1.55 is the
ability to use X or Y planes or define a custom plane.
The following options are available:
Distance This is the distance over which the entire colour ramp is stretched Offset The height at which shading starts. The shade value (0->1.0) is calculated as (z-offset Fit to Data Fits the Distance and Offset parameters to the point cloud data extents Axis The normal of the shading plane ie the direction in which the shader operates. This can be set to X, Y or Z
or an arbitrary vector. To set the plane on a 'face' of points:
This can be useful to bring out detail in surfaces with gentle relief. Edge Determines the behaviour of the shader beyond the shading range that is offset > z >
offset + distance or 0 > shade value > 1.0 Repeat The ramp is repeated Clamp The ramp is clamped to the edge value so all values > 1 are
clamped to 1 and all values < 0 are clamped to 0. Black A black value is assigned to points outside the range. Ramp Sets the shading colour ramp. Note that this lists all the available ramps although
some are not very useful for plane shading. General Tab
Memory Usage This determines the amount of available memory that Pointools should use. This setting is best left unchanged for
optimum performance. If you want Pointools to use less memory change this value by small amounts until you have
freed the required amount of memory. Delayed Channel Loading Point clouds consist of a number of channels: Geometry, Intensity, RGB Colour and Normals. Often a subset of these
channels are required for rendering the points depending on the settings in use. This option delays loading of unused
channels until they are required. As a consequence general loading is quicker but changing display options may
require loading of additional channels and so is slower. The option is off by default. Display Tab
Dynamic View Options
Minimum Output % Sets the minimum percent of the entire point cloud data set to be drawn during dynamic navigation. This overrides
the frame rate reduction. Setting high values will significantly improve the quality of the view whilst navigating but
at the expense of the frame rate. Front Bias Sets a bias to point closer to the viewer when reducing the view during navigation. This is most suitable for views of
objects viewed from the exterior where the points closest to the viewer are most often those of interest. Conversely
this option will not work well when viewing objects from inside. This option is off by default. Adaptive Point Size During navigation Pointools adaptively reducing the point density in different areas of the point cloud to suit the
current view. The Adaptive Point Size option compensates for density reduction by increasing the point size. This
results in a much fuller view whilst navigating. This option is off by default. Static View Options
Static View Reduction Optimizer Pointools optimizes the display of static views by calculating an optimum amount of data to display for different
parts of the point cloud data. This percentage value influences the aggressiveness of the optimizer. Higher values
result in faster display but may start to drop out some detail. If you find that detail is being dropped out of the static view, reduce the optimizer value. If you are viewing large amounts of data, increase this value until the reduction becomes apparent. This can
dramatically improve performance and reduce memory usage. Note that this is not a simple linear reduction of the amount of data on screen but an adjustment of localised density
estimation to adapt this estimation to different scenarios. Point Size Sets the point display size. This can also be set from the toolbar or by using the keyboard shortcuts 1-5. Scanner Display If scanner locations of the point cloud data are known these can be displayed in the viewport
in one of the following ways: None Does not display scanners. Axis Scanners are displayed as an 1m oriented axis. Point Scanner are displayed as a 10 pixel point. When viewing large or complex point cloud scenes it can be helpful to isolated the area (or volume) of interest.
Pointools enables this via the editable clip box tools.
The clip toolbar contains all icons for the clip box commands.
Editing the Clipbox
To edit the clipping box position and size:
Use the Extents button to reset the clip box to the extents of the data.
Disappearing Data
When importing different data sets be sure to check if clipping is active as it is
possible to leave clipping active from a previous data set. If you import a new data set
you may not see any data in the viewport because the data is clipped out entirely.
Section Viewer
The section view tool provides a convenient way to move a thin clip box to view a sections through the data. The
section viewer will use the the box axis with the shortest dimension to move through.
To activate the section viewer select Section viewer from the clip box dialog or the clipping toolbar. This opens the
section viewer options with the following controls:
The slider The slider sets the position of the box along its shortest axis. Mark Sets the extent of the slider range. The left Mark option indicates the lower end of the range. Nudge >> Nudges the section box in the positive direction. Nudge << Nudges the section box in the negative direction. Hide Box Hides the box, this does not effect the clipping which is set independently. Show Box Shows the box, this does not effect the clipping which is set independently. Hardware Support
The clip box utilises the ARB Vertex Shader extension to OpenGL. Whilst support for this is commonly available on
most graphics cards you may need to update your graphics driver to enable this feature.
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