| Routine ID: XINT002 | |
|---|---|
| Author(s): | Submitted: 15.06.84 |
| Origin: Same | Revised: 20.03.94 |
GEANT specific commands.
Clipping commands. The hidden line removal technique is necessary to visualize properly very complex detectors. At the same time, it can be useful to visualize the inner elements of a detector in detail. For this purpose, the commands menu CVOL has been developed: these commands allow subtractions (via boolean operation) of given shapes from any part of the detector, therefore showing its inner contents. It is possible to clip each different volume by means of a different shape (BOX , TUBE, CONE, SPHE are available). If '*' is given as the name of the volume to be clipped, all volumes are clipped by the given shape. A volume can be clipped at most twice (even by different shapes); if a volume is explicitely clipped twice, the '*' will not act on it anymore. Giving '.' as the name of the volume to be clipped will reset the clipping.
BOX cnnv [ xmin xmax ymin ymax zmin zmax ]
| CNNVC Name of volume to be clipped D='* 'XMINR Lower limit of the Shape X coordinate D=-10000.XMAXR Upper limit of the Shape X coordinate D=-9999.YMINR Lower limit of the Shape Y coordinate D=-10000.YMAXR Upper limit of the Shape Y coordinate D=-9999.ZMINR Lower limit of the Shape Z coordinate D=-10000.ZMAXR Upper limit of the Shape Z coordinate D=-9999. |
This command performs a boolean subtraction between the volume CNVV and a box placed in the MARS according the values of the given coordinates. See also CVOL. The following commands will clip by a box, with a vertex at the origin, the volume specified by NAME (a valid string for the NAME of the volume can be found using the DTREE command).
EXAMPLE -
dopt hide on
satt * seen -2
draw NAME 40 40 0 10 10 .01 .01
next
box NAME 0 1000 0 1000 0 1000
draw NAME 40 40 0 10 10 .01 .01
box .
TUBE cnvv [ rmax zdem xmed ymed zmed ]
| CNVVC Name of volume to be clipped D='* 'RMAXR External radius of tube D=0.1ZDEMR Half length of tube axis D=0.1XMEDR Center X coordinate D=-10000.YMEDR Center Y coordinate D=-10000.ZMEDR Center Z coordinate D=-10000. |
This command performs a boolean subtraction between the volume CNVV and a tube; the tube has the given parameters and is placed in the MARS according the given coordinates of its center. See also CVOL. The following commands will clip, by a tube, positioned according to the given parameters, the volume specified by NAME (a valid string for the NAME of the volume can be found using the DTREE command).
EXAMPLE -
dopt hide on
satt * seen -2
draw NAME 40 40 0 10 10 .01 .01
next
tube * 500 1000 500 0 0
draw NAME 40 40 0 10 10 .01 .01
box .
CONE cnvv [ rmax1 rmax2 zdem xmed ymed zmed ]
| CNVVC Name of volume to be clipped D='* 'RMAX1R Min external radius D=0.1RMAX2R Max external radius D=0.1ZDEMR Half length of cone axis D=0.1XMEDR Center X coordinate D=-10000.YMEDR Center Y coordinate D=-10000.ZMEDR Center Z coordinate D=-10000. |
This command performs a boolean subtraction between the volume CNVV and a cone; the cone has the given parameters and is placed in the MARS according to the given coordinates of its center. See also CVOL. The following commands will clip by a cone, positioned according the given parameters, the volume specified by NAME (a valid string for the NAME of the volume can be found using the DTREE command).
EXAMPLE -
dopt hide on
satt * seen -2
draw NAME 40 40 0 10 10 .01 .01
next
cone * 1 750 1000 0 0 1000
draw NAME 40 40 0 10 10 .01 .01
box .
SPHE cnvv [ rmax xmed ymed zmed ]
| CNVVC Name of volume to be clipped D='* 'RMAXR External radius of sphere D=0.1XMEDR Center X coordinate D=-10000.YMEDR Center Y coordinate D=-10000.ZMEDR Center Z coordinate D=-10000. |
This command performs a boolean subtraction between the volume CNVV and a sphere; the sphere has the given parameters and is placed in the MARS according to the given coordinates of its center. See also CVOL. The following commands clip by a sphere, positioned according to the given parameters, the volume specified by NAME (a valid string for the NAME of the volume can be found using the DTREE command). EXAMPLE -
dopt hide on
satt * seen -2
draw NAME 40 40 0 10 10 .01 .01
next
sphe * 500 0 0 500
draw NAME 40 40 0 10 10 .01 .01
box .
VALCUT xcut ycut zcut
| XCUTRx coordinate of cutted value D=0.YCUTRy coordinate of cutted value D=0.ZCUTRz coordinate of cutted value D=0. |
It allows the cutting in the ray-tracing. All the volumes are cutted from XCUT to +BIG along the x axis, from YCUT to +BIG along the y axis and from ZCUT to +BIG along the z axis.
Drawing commands. These commands allow the visualization in several ways of the volumes defined in the geometrical data structure. It is possible to draw the logical tree of volumes belonging to the detector (DTREE), to show their geometrical specification (DSPEC,DFSPC), to draw them and their cut views (DRAW, DCUT). Moreover, it is possible to execute these commands when the hidden line removal option is activated; in this case, the volumes can be also either translated in the space (SHIFT), or clipped by boolean operation (CVOL). In addition, it is possible to fill the surfaces of the volumes with solid colours when the shading option (SHAD) is activated. Several tools (ZOOM, LENS) have been developed to zoom detailed parts of the detectors or to scan physical events as well. Finally, the command MOVE will allow the rotation, translation and zooming on real time parts of the detectors or tracks and hits of a simulated event. Ray-tracing commands. In case the command (DOPT RAYT ON) is executed, the drawing is performed by the Geant ray-tracing; automatically, the color is assigned according to the tracking medium of each volume and the volumes with a density lower/equal than the air are considered transparent; if the option (USER) is set (ON) (again via the command (DOPT)), the user can set color and visibility for the desired volumes via the command (SATT), as usual, relatively to the attributes (COLO) and (SEEN). The resolution can be set via the command (SATT * FILL VALUE), where (VALUE) is the ratio between the number of pixels drawn and 20 (user coordinates). Parallel view and perspective view are possible (DOPT PROJ PARA/PERS); in the first case, we assume that the first mother volume of the tree is a box with dimensions 10000 X 10000 X 10000 cm and the view point (infinetely far) is 5000 cm far from the origin along the Z axis of the user coordinates; in the second case, the distance between the observer and the origin of the world reference system is set in cm by the command (PERSP NAME VALUE); grand-angle or telescopic effects can be achieved changing the scale factors in the command (DRAW). When the final picture does not occupy the full window, mapping the space before tracing can speed up the drawing, but can also produce less precise results; values from 1 to 4 are allowed in the command (DOPT MAPP VALUE), the mapping being more precise for increasing (VALUE); for (VALUE = 0) no mapping is performed (therefore max precision and lowest speed). The command (VALCUT) allows the cutting of the detector by three planes ortogonal to the x,y,z axis. The attribute (LSTY) can be set by the command SATT for any desired volume and can assume values from 0 to 7; it determines the different light processing to be performed for different materials: 0 = dark-matt, 1 = bright-matt, 2 = plastic, 3 = ceramic, 4 = rough-metals, 5 = shiny-metals, 6 = glass, 7 = mirror. The detector is assumed to be in the dark, the ambient light luminosity is 0.2 for each basic hue (the saturation is 0.9) and the observer is assumed to have a light source (therefore he will produce parallel light in the case of parallel view and point-like-source light in the case of perspective view).