Advanced steps with Simple Geo Chris Theis Overview

Advanced steps with Simple. Geo Chris Theis

Overview Different visualization modes Geometry sections Visualization of biasing Volume & mass calculation Replicas Measures, Precision & geometry sharing

Visualization Biasing Volume & mass calculation Different visualization modes Typical problem – visualizing the “inside” of objects while preserving the full appearance of the surrounding structure Solution: 1. ) Define the material (e. g. concrete) transparent but this would render all concrete structures transparent 2. ) Use “X-ray” or “Edge ray” properties 3

Visualization Biasing Volume & mass calculation Different visualization modes 1. Select the body you would like to make transparent 2. In the “Viz attributes” section on the right of your screen choose either “X-ray mode” or “Edge-Ray mode” X-ray Edge-ray * The gradient background can be enabled via the menu “View Settings…” ** Always enable “Gouraud shading” for high quality plots (“View Shading…”)

Visualization Biasing Volume & mass calculation Different visualization modes Sketched contours (shaded) Sketched contours (non-shaded) “Hand drawn” contours

Visualization Biasing Volume & mass calculation Different visualization modes “Hand drawn” contours are user configurable via the menu “View Settings” dialog Frequency & amplitude = level of jittering Edge overrun => 0 = no over-drawn edges frequency = 0. 05 amplitude =0. 0004 edge overrun => 0. 1 frequency = 0. 005 amplitude =0. 0004 edge overrun => 0. 3 * Decreasing the frequency and the amplitude + enabling of anti-aliasing (“view” menu) yields thicker, chalk-like lines.

Visualization Biasing Volume & mass calculation Different visualization modes – interactive shadows Enabling shadows via the “View” Shadows menu enhances the depth of an image No shadows Hard shadows Soft shadows will be only available in SG versions > 4. 2 They can be configured via the “View” “Settings” dialog. Soft shadows More samples = nicer penumbra but longer calculation times (more powerful GFX card)

Visualization Biasing Volume & mass calculation Different visualization modes – CAD template Auto. CAD 2 D DXF files can be loaded as templates to be super-imposed with the 3 D geometry allows for comparing the CSG model to a technical drawing. (SG version > 4. 2!) 1. ) Select “CAD 2 D template” “Load” file 2. ) Select projection (XY, YZ, etc. ), unit and scaling factor in the dialog that pops up 3. ) Configure the display of the drawing in terms of position, rotation, axis dependent scaling, line styles Hint: The CAD template can be moved interactively by selecting the menu “CAD 2 D template” “Move CAD template”. It will be moved in the current work plane and by pressing Shift it can be moved perpendicularly

Visualization Biasing Volume & mass calculation Different visualization modes – CAD template

Visualization Biasing Volume & mass calculation Different visualization modes – rendering into images SG versions > 4. 2 support interactive rendering of geometries & also Da. Vis 3 D results into images.

Visualization Biasing Volume & mass calculation Different visualization modes – voxel geometries Da. Vis 3 D can be used to display cuts through voxel geometries. Since the end of 2010 it is possible to directly load FLUKA binary voxel geometry files. The colors are user configurable (see manual).

Visualization Biasing Volume & mass calculation Visualization of importance biasing Geometric importance biasing settings can be visualized by coloring their contours according to their importance. Allows for checking for erroneous discontinuities 1. ) Select “View Shading Render importance” 2. ) Set the importance range, number of colors as well as the color scheme.

Visualization Biasing Geometry sections Volume & mass calculation For better understanding we would like to “cut out” a part of the geometry or create a full section with a plane. 13

Visualization Biasing Geometry sections Volume & mass calculation l Create a body which will be used as a section body (cookie cutter) and place it at the correct position. l Select this body and choose from the menu “Edit Create section of whole geometry”. This will modify the whole geometry in order to subtract the respective body! The file extension is changed to “. sec. dat” to avoid mistaking this geometry, which is intended for visualization only, with an ordinary one that can be exported for simulations. 14

Visualization Biasing Geometry sections Volume & mass calculation Note: The parameters of the section body (size, position) can be changed even after it has been subtracted. All changes will be propagated immediately to the rest of the geometry. It is also possible to remove the section body from some regions in order to exclude them from being sliced. 15

Visualization Biasing Volume & mass calculation Biasing Task: Splitting of one body/region into several sub-regions for importance biasing 1. ) Select the body/region 2. ) From the (context) menu choose “Biasing wizard Splitting wizard” 3. ) Set the number of sub-regions, the dimension in splitting direction (=distance of the splitting planes) & splitting direction 4. ) Press okay full region description will be created automatically

Visualization Biasing Task: Creation of concentric, encapsulated structures 1. ) Select the body (only box, cylinder or sphere!) 2. ) From the (context) menu choose “Biasing wizard Concentric regions” 3. ) Set the geometry modification parameters Optionally the importances can be applied as well e. g. : entering 1. 4 would apply 1. 4 to the first region, 1. 4^2 to the second, 1. 4^3 to the third etc…. 4. ) Press okay full region description will be created automatically Volume & mass calculation

Visualization Biasing Volume & mass calculation What is the volume & the mass of this object? Select the object & from the context menu (right click) choose “Volume & mass calculation”

Replicas To create a complex geometry which contains several cloned replicas of one prototype as a full geometry instead of a virtual lattice copy one can use Simple. Geo’s replica function. 1. ) Create a prototype, e. g. , of a magnet 2. ) Do NOT include any surrounding regions with the exception of a box which contains your whole prototype. This facilitates the integration in the final geometry. 3. ) Save this prototype to a file. 4. ) Open the final geometry and choose “File Merge”. Select the file containing the prototype. 5. ) In the following dialog answer “Yes” to keep the prototype grouped.

Replicas 6. ) In the CSG tree you will find the prototype as a group named “Root”. You can change this name according to your preference. 7. ) Select the grouped prototype and modify its position parameters to place it correctly. 8. ) Subtract the container box of the prototype from its surrounding volume (etc. the surrounding air) 9. ) Create a replica of the grouped prototype (Ctrl + C) a fully independent clone will be created with independent body primitives. Move this replica to its final position by changing its position parameters. Repeat step 8 and continue as often as you would like. ATTENTION: The new regions/bodies will carry unique names based on the original names + suffix. Some codes like FLUKA have a limit of 8 -10 characters for names!! Thus, one might have to manually adapt these names if they become too long. For codes like PHITS this does not pose a problem as Simple. Geo’s exporter automatically converts names to numbers. NOTE: Please read also the “Create replicas” section in the manual for further information.

Replicas Measures 2 D/3 D Precision

Replicas Measures 2 D/3 D Precision Measures (2 D/3 D) What are the dimensions of this object? You can measure dimensions/distances in 2 D or in 3 D but you need to pay attention to the following constraints: 2 D: - Distances/measures can be defined freely without any dependence on the geometry - Results are only meaningful if the measures are placed in parallel and not in perspective view. the view should be aligned to the axis-system of the geometry (use F 1, F 2, F 3 keys, etc…) 3 D: - Distances can be measured independently of the perspective - as the screen/mouse are 2 D devices the third coordinate for the start/end of the measure has to be obtained from a list of known points bound to geometry vertices

Replicas Measures 2 D/3 D Precision Measures (2 D) 1. ) Press F 10 or select. This will automatically change into the parallel projection mode. 2. ) Choose the most suitable perspective (F 1, F 2, F 3 etc…) 3. ) Click once on your geometry to define the starting point. While moving the mouse the actual distance w. r. t. start will be shown next to the cursor. 4. ) Click again to define the end point. 5. ) Press Esc to remove all measures from the screen. Try also to automatically obtain horizontal & vertical measures. The number of displayed digits can be configured via the menu “View Settings”.

Replicas Measures 2 D/3 D Measures 3 D 1. ) Click on 2. ) All vertices will be marked with green points. The size of the points can be changed via “View Settings” in the field “Snap/Debugpoint size”. 3. ) Click on the first vertex to define the starting point. 4. ) Click on another vertex to define the end point. Precision

Replicas Measures 2 D/3 D Precision • Internally SG uses full double precision for calculations. However, by default only 2 digits, which equals for example 1/100 cm for FLUKA, will be used in the property view. • You can enter more digits but they will be rounded to 2 in the view for display but not internally for geometry creation! • The FLUKA, PHITS & MCNP(X) export filters usually use 2 digits with some exception like arbitrary planes which require higher accuracy. • It is possible to increase the number of digits that are displayed as well as exported. Via the menu “View Settings” you can open a dialog and request a larger number in the field “Number of property digits”. Note: A larger number of digits does not always reflect higher accuracy! We are dealing with binary floating point arithmetic!! Currently only the export modules for FLUKA & PHITS support a configurable number of digits.

Mail/Copy/Paste Sharing geometries/images l Mailing of geometries or images is supported directly from within Simple. Geo. Just select “File Send” and “Geometry” or “Image”. This will send either the full geometry (incl. the material database) or the currently rendered image to a mail recipient. l Images can be transferred directly from Simple. Geo to other applications like Word etc. For this purpose two options are available: n n Copy the full image to the clipboard (Ctrl + Alt + P or via the “Edit” menu) Copy region of the image to the clipboard (Ctrl + Alt + R or via the “Edit” menu) In this case the user can define the copied region by dragging a rectangle over the screen.

Thank you for your attention Website: www. cern. ch/theis/simplegeo Author: Christian. Theis {at} cern. ch 27