<< Click to Display Table of Contents >> Navigation:  Ground Modelling > Analysis & Colour mapping > Z value

Purposes

1.To provide a graphical representation of the Z values in a model when typical output may be thought of as "colour filled contours".

2.With a difference model created by menu item Ground Modelling, Volumes the Z values represent amounts of cut and fill. You can present the cut and fill depths as a coloured map (isopachytes) and also report the cut and fill volumes based on depths.

3.When a visibility model has been output by menu item Ground Modelling, ZTV the Z values normally relate to how many targets are visible and results may now be presented with user defined colours. From KTF version 8.5812 onwards a ZTV Target filter option is also available with visibility models.

4.To draw a horizontal water surface or flood area defined by specific water level.

 

 

Operation

Select the model and the dialogue appears. Note the range of Z values in the model – these may be actual existing or design levels, cut and fill amounts or relate to the number of ZTV targets.

 

Choose the colour definition method :-

 CAD colours to select from the CAD Colour Index (colour by numbers as above). Each band is drawn on its own layer.

 or

 True colours to use the far greater range and produce "smoother and more subtle" results.

 

 

CAD colours

Add    

To individually add a new colour band by entering start and end Z values and assigning layer and colour.

 

Auto    

To assign bands automatically. Overwrite the defaults if required. Start and end Z values are rounded to the nearest metre with colour numbers starting at 10 and incrementing at intervals of 10.

 

Transform    

To modify the elevation bands. The Divide Z range automatically option enables a "favourite" colour banding that was saved in a .ele file to be expanded or reduced over the vertical range. The Start Z and interval settings enable modifications to the start or lowest Z value and interval. To reverse automatic banding enter the highest Z value as the lowest Z value in the dialogue and interval of -1.000 for example.

 

Edit    

To edit a highlighted colour band.

 

Delete    

To remove highlighted colour band from the list.

 

Clear    

To remove all bands in list.

 

Open    

To read colour banding from an existing .ele file.

 

Save as    

To write colour banding to a .ele file.

 

True colours

Add    

To select start colour and set the span or range. Default is to divide the vertical range into 128 steps but this can be changed by the slider and "fine tuned" with the keyboard left and right arrow keys. For a cut and fill presentation good results may be achieved by setting three or four steps from the lowest fill value (rounded down to a suitable value) for the Bottom Z up to 0.000 and then click the Add... button to set contrasting colours with three or four steps from 0.000 to the Top Z (rounded up to a suitable value).

Select... to fix the start colour and user the sliders to achieve your choice of colours.

Layer... to fix the layer for the colour mapping.

<-Previous and Next-> buttons enable to control what "set" you work on.

 

Edit    

To edit elevation bands.

 

Clear    

To remove all bands.

 

Open    

To read the true colour banding from an existing .caf file.

 

Save as    

To write colour banding to a .caf file.

 

 

 

Output settings

Draw Solids    

Suitable for 2D plan presentation.

 

Draw 3D Faces

Suitable for 3D views.

 

Draw Polylgons (for hatching)

This option is only available for models created with Gridding. Draws closed 2D polylines for each Z value band.

 

Zoom extents

To easily see all the colour mapping when drawn.

 

Volumes

This option is available only for Differencial Models. Calculates the cut and fill volumes for each Z value band. After calculating use the Report file... button to write the report file as below :-

Cut depths              Volume            Area

0.000    to    0.500    41.0%  786        1855    

0.500    to    1.000    27.0%  518        1206    

1.000    to    1.500    18.2%  348        894      

1.500    to    2.000    10.1%  194        539      

2.000    to    2.500     3.3%  63         231      

2.500    to    3.000     0.3%  6          41      

 

Fill depths             Volume            Area

0.000    to    0.500    47.4%  930        2070    

0.500    to    1.000    28.0%  548        1543    

1.000    to    1.500    12.0%  235        693      

1.500    to    2.000     8.0%  156        374      

2.000    to    2.500     4.4%  86         252      

2.500    to    3.000     0.3%  6          63      

 

Decimals

Number of decimals in volume values. With very small amounts it is handy to have more accurate values than whole cubic metres.

 

Z Projection

True Z values    

Outputs represent actual Z values in the model.

 

Upper limit(s) e.g. water  

Typical use is when just one elevation band has been defined in CAD colours (e.g. as blue) to define a flood or water level and the output Solids or 3D Faces will show all areas at or below the upper Z value in the band (the lower level should be 0.000 or less if some levels in the site are close to sea level for example). If this setting is applied to the whole band set then the result if output as 3D Faces and rendered produces a terraced effect.

 

Flat surface (0.000)    

To draw Solids or 3D Faces at 0.000 elevation (2D output).

 

Drape on 2nd model

To lay over or project the colour analysis results onto a 2nd model. This is useful for presenting cut and fill or ZVI result colour mapping onto what would typically be the original survey ground model. Output should be set to 3D Faces.

 

Calculate and Draw

Click to calculate the bands and draw as Solids or 3D Faces.

The areas for each colour band are displayed in the dialogue if using CAD colours.

 

Report file...

To write a report file following the above calculation.

 

Colour Key

To provide a key to the colour and Z value relationship. Note that where there are more than one "sets" of true colours the keys need to be drawn separately and in the cut and fill example below they have been repositioned.

 

 

 

Filter by Targets

When a post KTF V8.5812 visibility model is selected an additional option to filter the colour banding by selected Targets. This enables to present the visibility of the western side of the project with different colour than eastern side's visibility for example.  

 

Select the Target(s) you want to include in colour banding and proceed normally. Only the areas where Receptor can see the selected Target(s) will be coloured.