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| 2 | G4RayTracer version 1.0 (29/Jan/00) |
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| 3 | |
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| 4 | 1. Introduction |
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| 5 | |
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| 6 | G4RayTracer is a "ray tracing" package which uses Geant4 kernel mechanism |
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| 7 | of tracking/navigation. It visualizes any kinds of solids that Geant4 |
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| 8 | kernel can navigate. |
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| 9 | |
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| 10 | 2. Building a library |
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| 11 | |
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| 12 | G4RayTracer is one of visualization driver which Geant4 supports. To build |
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| 13 | a library of G4RayTracer (library name G4RayTracer), set an environment |
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| 14 | variable G4VIS_BUILD_RAYTRACER_DRIVER. |
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| 15 | |
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| 16 | $ setenv G4VIS_BUILD_RAYTRACER_DRIVER 1 |
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| 17 | |
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| 18 | 3. Using G4RayTracer |
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| 19 | |
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| 20 | To use G4RayTracer, set an environment variable G4VIS_USE_RAYTRACER. |
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| 21 | |
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| 22 | $ setenv G4VIS_USE_RAYTRACER 1 |
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| 23 | |
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| 24 | Also, G4RayTracer has to be registored to the user's concrete VisManager. |
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| 25 | Refer an example given in |
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| 26 | geant4/source/visualization/management/include/MyVisManager.cc. |
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| 27 | |
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| 28 | 4. Notes |
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| 29 | |
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| 30 | a) G4RayTracer generates JPEG file(s). To visualize these files, use your |
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| 31 | local program such as NetScape or xview, etc. |
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| 32 | |
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| 33 | b) The eye position must be inside of the defined world volume. If you want |
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| 34 | to draw your detector setup from very far position, you need to enlarge |
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| 35 | your world volume. |
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| 36 | |
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| 37 | c) G4RayTracer ignores volumes without G4VisAttributes, volumes which are |
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| 38 | set as "forced wire frame", and volumes which are set as "invisible". |
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| 39 | |
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| 40 | d) In case you get unexpected figure, check |
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| 41 | d.1) eye position and target position are properly set, |
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| 42 | d.2) light direction is properly set (note light direction is from |
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| 43 | illumination light source to the objects), |
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| 44 | d.3) span angle (given by angle for 100 pixels) is reasonable, |
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| 45 | d.4) there is no surrounding volume(s) without transparency. |
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| 46 | |
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| 47 | e) G4RayTracer can be executed ONLY AT "Idle" state. |
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| 48 | |
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| 49 | 5. Basic UI commands |
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| 50 | |
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| 51 | a) /vis/rayTracer/eyePosition x y z unit |
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| 52 | eye position |
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| 53 | |
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| 54 | b) /vis/rayTracer/target x y z unit |
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| 55 | target position |
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| 56 | in default it is set to the origine |
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| 57 | |
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| 58 | c) /vis/rayTracer/lightDirection ex ey ez |
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| 59 | vector of the illuminating light (need not to be a unit vector) |
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| 60 | note light direction is from illumination light source to the objects |
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| 61 | |
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| 62 | d) /vis/rayTracer/column nColumn |
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| 63 | number of holizontal pixels |
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| 64 | in default 640 pixels |
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| 65 | |
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| 66 | e) /vis/rayTracer/row nRow |
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| 67 | number of virtical pixels |
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| 68 | in default 640 pixels |
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| 69 | |
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| 70 | f) /vis/rayTracer/span angle unit |
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| 71 | angle for 100 pixels |
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| 72 | in default 5 degree |
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| 73 | |
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| 74 | g) /vis/rayTracer/trace fileName |
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| 75 | execution of G4RayTracer |
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| 76 | "fileName" is the out put JPEG file name |
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| 77 | in default "g4RayTracer.jpeg" |
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| 78 | NOTE THAT THIS COMMAND IS AVAILABLE ONLY AT IDLE STATE |
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| 79 | |
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| 80 | |
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| 82 | |
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