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root/radiance/ray/src/util/trad.hlp
Revision: 2.5
Committed: Sun Nov 6 09:39:09 1994 UTC (29 years, 4 months ago) by greg
Branch: MAIN
Changes since 2.4: +2 -6 lines
Log Message:
removed small statement about slow help restart

File Contents

# Content
1 $Id$
2
3 This help file is associated with the trad interface to the Radiance
4 rad(1) program. Trad consists of trad.wsh and one do_*.tcl file for
5 each screen. There are currently seven such screens: Action, File,
6 Options, Results, Scene, Views and Zone.
7
8 .Trad.Intro
9
10 Trad is a graphical user interface (GUI) to the
11 rad(1) program, which controls the operation of the basic
12 Radiance scene compiling, rendering and picture filtering programs.
13 Trad also includes links to a few utilities for displaying and
14 converting results, but most of what it does can be done by editing a
15 small text file, called the "rad input file".
16 Scene creation still requires the use of a text or graphical editor,
17 or translation from some external CAD format.
18
19 Trad interaction is broken into seven screens.
20 Each screen is accessed by pressing its associated radio
21 button along the right-hand side of the main window.
22 If trad is started with no file name, the File screen is displayed,
23 and you must pick a valid rad input file before any other screen may
24 be accessed.
25 If a name is given for a file that doesn't exist, trad goes to the
26 Scene screen and prompts you to enter the names of one or more
27 Radiance scene description files.
28 If a rad input file exists already, trad determines if there are
29 renderings still to be done or if everything is finished.
30 If there is still work to be done, trad opens first with the Action
31 screen.
32 If all renderings are complete and up-to-date, trad opens right to
33 Results screen.
34
35 For additional guidance on Radiance in general, consult the Radiance
36 Tutorial, Reference Manual, and man pages.
37 In particular, it is a good idea to read through the rad(1) man page
38 before using this interface.
39
40 To find out how to get more help, press the "Next" button to the
41 right.
42
43 .Trad.Help
44
45 If you have specific questions about trad, search through the
46 category and topic menus on this help window, or press and release
47 the left mouse button while holding the control key over the object of
48 curiosity in the main trad window.
49 (In general, only active windows are given help file links -- click
50 on these rather than the text labels.)
51 Additional search capabilities are available over all topics using
52 the "Grep" button.
53
54 For help on the help facility itself, Control-click on the problem
55 help widget or on the window title in the upper right corner for
56 more general information.
57 (To get back to trad-specific help, press the "HELP" button in the
58 main trad window or Control-click on a trad widget.)
59
60 .Trad.Messages
61
62 Informative messages, commands executed by rad, and errors
63 appear in the message window at the bottom of the trad frame.
64 Growing the trad window means growing this message window, and
65 not much else.
66 This is not really necessary, since the window will be grown
67 automatically if the message requires it.
68
69 Serious errors will be accompanied by the sounding of the bell.
70
71 .Trad.Quit
72
73 To quit the trad application, press the "Quit" button at any time.
74 If you have made changes to the rad input variables, you will be
75 asked prior to program exit if you want to save your changes first.
76
77 Any batch process running in the background will continue to run,
78 and the associated error messages will be viewable by
79 trad later when you open the same rad input file.
80
81 .File.Intro
82
83 This button selects the trad File screen, which allows rad input
84 files to be loaded and saved, and new files to be created.
85
86 .File.Load
87
88 This button loads the selected file into trad.
89 If the current file has been changed and these changes have not been
90 saved, you will be given first the opportunity to save your changes.
91
92 The actual load operation may take several seconds or even minutes,
93 depending on the status of the rendering process.
94 This is because the rad program itself is used to interpret the
95 input file, and if there is no up-to-date octree associated with the
96 file, it is necessary to run getbbox on the entire scene
97 before the variable values can be set.
98 It is possible to eliminate this delay in future loads by going to
99 the Action screen and running oconv.
100
101 If the opened file has read-only mode set (see chmod(1)), then the
102 "Read Only" check box will be lit.
103 Unchecking this box means that it will be possible to save the file
104 later, though the actual mode on the file will not be changed until
105 it is saved.
106 Loading a writable file always clears the "Read Only" check box.
107
108 If an error is encountered while trying to load the file, a message
109 will be printed in the box at the bottom.
110
111 .File.Save
112
113 The "Save" button in the File screen saves any changes to the
114 current file.
115 This information is saved in the original file by default, but may
116 be saved in another file by entering a new name in the "File" field.
117 If this new file already exists, a dialogue box will ask if you really
118 want to overwrite it.
119 If the file name is different than the original
120 one loaded, the "Read Only" check box will be ignored.
121
122 .File.New
123
124 The "New" button clears all rad variables in preparation for
125 writing a new rad input file.
126 If the file selected already exists, a warning box will ask if you
127 really want to ignore the previous file contents.
128 If you agree, then no warning will be given when the file is later
129 overwritten.
130
131 .File.ReadOnly
132
133 The "Read Only" check box permits you to indicate that the opened
134 file should not be overwritten.
135 This box will be checked automatically if the permissions on the
136 edited file do not allow writing by the user.
137 If the box is subsequently unchecked, trad will attempt to change
138 permissions and write to the file when a save is requested.
139 If this fails, an error message will indicate the problem.
140
141 .Scene.Intro
142
143 This button selects the trad Scene screen.
144 On this screen, you may enter the octree file and the scene files
145 that go into it, as well as any mkillum or other files on which the
146 scene depends.
147 These files are generally produced by hand in a text editor or by
148 conversion from an external CAD format, such as DXF.
149 (See the Radiance Reference Manual and Radiance Tutorial for details on the
150 information contained in these files.)
151
152 To enter a file of a particular type, press the corresponding button
153 to get a dialogue box that allows you to pick existing files from any
154 directory.
155
156 Use the "Discard" button to remove one or more files from a specific
157 list.
158 The actual file is untouched.
159
160 .Scene.Octree
161
162 The "Octree" entry in the Scene screen names the octree file to be
163 compiled by oconv from the materials and scene files.
164 (See the oconv(1) man page for more details.)
165
166 If make(1) is being used to build the octree, you should leave all
167 other windows on this screen empty.
168 The octree can still be rebuilt from trad by pressing the "oconv"
169 or "Force" buttons on the Action screen, but normally it is
170 expected to be current.
171 In particular, an unsupported octree must exist before loading
172 a rad input file on which it depends.
173
174 The default octree name is the root name from the render input file
175 plus ".oct".
176 If mkillum is being used (i.e. one or more illum files is given),
177 then two additional octrees will be created, named the same except
178 for an additional "0" or "1" immediately before the file suffix
179 (normally ".oct").
180
181 To delete the named octree, and therefore force the scene to be
182 recompiled and all the pictures to be rerendered, use the "Delete"
183 button next to the octree window.
184
185 .Scene.OctDelete
186
187 The "Delete" button next to the octree window removes the named
188 octree from the filesystem, forcing the scene to be later recompiled
189 and all the pictures to be rerendered (if desired).
190 This is appropriate if you add or remove materials, scene or illum
191 files from one or more lists, or make some change to a materials file
192 that requires the octree to be rebuilt (such as adding or removing
193 individual materials).
194
195 Verification is required before the octree will be deleted.
196
197 You can achieve the same effect as manually removing the octree by
198 pressing the "Force" button on the scene compilation section
199 of the Action screen.
200 (See the "Force" topic under the "Action" help category for more
201 information.)
202
203 .Scene.Materials
204
205 Materials files generally contain Radiance material descriptions
206 only, not geometry.
207 The purpose of listing them separately is so that minor changes to
208 material parameters will not force the octree to be rebuilt,
209 incurring an additional delay that is unnecessary.
210
211 The "Materials" button is used to add materials files to the list.
212 A dialogue box appears when you press this button and allows you to
213 select files to be included.
214 Each new selection is added to the end of the materials list.
215 The default matching pattern for material files is "*.mat".
216 This may of course be reassigned within the file selection window.
217
218 The list box showing the current materials may be edited in three
219 ways besides the dialogue for adding files.
220 First, entries may be removed from the list
221 using the "Discard" button.
222 Second, entries may be moved within the box by selecting them with
223 the left mouse button and clicking the middle mouse button over the
224 entry you wish to place the selected items above.
225 If you wish to put the selected items at the very end of the list,
226 click the middle mouse button below the last entry.
227 Third, entries may be moved from other windows by
228 selecting them and pressing the middle button.
229 This works for the list boxes on this screen as well as selections
230 in other windows on the display.
231
232 The order of materials files is usually unimportant, but sometimes
233 there are definitions in later files that depend on prerequisites in
234 earlier files.
235 An example of this is a window illum source that depends on a sky
236 description file, which must appear before it.
237 The order of files shown in the list is the order they will be given
238 to oconv and therefore to the rendering programs.
239
240 .Scene.Illum
241
242 Illum files are Radiance scene descriptions that contain surfaces
243 to be converted into illum sources by mkillum(1).
244 Please consult the manual page for mkillum and understand the
245 Radiance Tutorial before using this box, since these files differ slightly
246 from standard Radiance scene descriptions.
247
248 The "Illum" button is used to add illum files to the list.
249 A dialogue box appears when you press this button and allows you to
250 select files to be included.
251 Each new selection is added to the end of the illum list.
252 The default matching pattern for material files is "*.rad".
253 This may of course be reassigned within the file selection window.
254
255 The list box showing the current illum files may be edited in three
256 ways besides the dialogue for adding files.
257 First, entries may be removed from the list
258 using the "Discard" button.
259 Second, entries may be moved within the box by selecting them with
260 the left mouse button and clicking the middle mouse button over the
261 entry you wish to place the selected items above.
262 If you wish to put the selected items at the very end of the list,
263 click the middle mouse button below the last entry.
264 Third, entries may be moved from other windows by
265 selecting them and pressing the middle button.
266 This works for the list boxes on this screen as well as selections
267 in other windows on the display.
268
269 .Scene.Scene
270
271 Scene files give the geometry and (perhaps) some of the materials
272 used in a particular Radiance model.
273 These files are given to oconv(1) in the order specified.
274 The ordering of files is usually not important, unless some later
275 files use materials or other modifiers defined in earlier files.
276
277 The "Scene" button is used to add scene files to the list.
278 A dialogue box appears when you press this button and allows you to
279 select files to be included.
280 Each new selection is added to the end of the scene list.
281 The default matching pattern for material files is "*.rad".
282 This may of course be reassigned within the file selection window.
283
284 The list box showing the current scene files may be edited in three
285 ways besides the dialogue for adding files.
286 First, entries may be removed from the list
287 using the "Discard" button.
288 Second, entries may be moved within the box by selecting them with
289 the left mouse button and clicking the middle mouse button over the
290 entry you wish to place the selected items above.
291 If you wish to put the selected items at the very end of the list,
292 click the middle mouse button below the last entry.
293 Third, entries may be moved from other windows by
294 selecting them and pressing the middle button.
295 This works for the list boxes on this screen as well as selections
296 in other windows on the display.
297
298 .Scene.Objects
299
300 Object files are files on which the given octree depends, but which
301 are not included directly on the oconv command line.
302 If any of these files is modified, then it is assumed that the
303 octree must be rebuilt.
304
305 To automatically determine which files in the working directory
306 affect the octree, press the "Auto" button just below the "Objects"
307 button.
308 Note that this will only add files to the object list.
309 If you wish to completely replace what is already there, you must
310 therefore select all the files and use the "Discard" button before
311 pressing "Auto".
312
313 .Scene.Discard
314
315 The "Discard" button removes the selected file names from a list.
316 The actual files are untouched, of course.
317 (Some care should be taken here, since there is no undo
318 function associated with this window other than reloading the
319 original information with the "Revert" button.)
320
321 .Scene.Edit
322
323 Use the "Edit" button to open a text editor on the selected file(s).
324 This is a convenient way to look at and change the contents of the
325 Radiance input files.
326
327 .Scene.Copy
328
329 The "Copy" button may be used to selectively copy the scene file
330 information from another rad input file.
331 Specifically, the variables "OCTREE, materials, illum, scene and
332 objects" will be read in to replace the current values.
333
334 All other variables will be unaffected.
335
336 .Scene.Revert
337
338 The "Revert" button is a convenient way to revert to the original
339 values in the rad input file.
340 Only the variables on the Scene screen will be affected, but any changes
341 to these variables since the last save will be lost.
342
343 .Zone.Intro
344
345 This button selects the trad Zone screen.
346 On this screen, the user should enter the maximum and minimum
347 coordinates of the zone of interest for this set of renderings.
348 This zone need not correspond exactly to any interior or exterior
349 walls, as it is used primarily to set rendering parameters and
350 standard viewpoints.
351
352 An interior zone means that standard viewpoints will be selected
353 from the inside of this box.
354 An exterior zone means that standard viewpoints will be selected
355 from the outside of this box.
356 The default zone is an exterior one computed from the bounding box
357 of the entire scene.
358 (Note that this is not usually desirable.)
359
360 In addition to the ZONE variable, this screen offers the ability
361 to set four other rad variables that are generally associated with a
362 particular scene and a particular zone.
363 These are the rad DETAIL, INDIRECT, VARIABILITY and EXPOSURE
364 variables.
365 For more information on these topics, use the Topic menu or consult
366 the rad manual page.
367
368 .Zone.Type
369
370 There are two types of zones understood by rad, "Interior" and
371 "Exterior".
372 An interior zone is indicated when renderings generally take place
373 inside a specified 3-d box.
374 A typical example might be a single room or auditorium.
375 An exterior zone is indicated when renderings generally take place
376 outside a specified 3-d box, which is the focus of attention.
377 A typical example might be a building exterior or a single object,
378 such as a chair.
379
380 .Zone.Zone
381
382 A zone is specified by six real numbers, corresponding to the world
383 coordinates of the box's corners.
384 Zone boxes are always axis-aligned, therefore one need only specify
385 the minimum and maximum X, Y, and Z coordinates.
386
387 The exact values of these coordinates is not terribly important, as
388 they are only used to guide the setting of certain rendering
389 parameters and standard view positions.
390 It does not matter for instance whether the values lie on the inside
391 or the outside of walls, or if there are non-rectilinear geometries
392 defining the space perimeter.
393 In fact, the whole space may not even be aligned with the X, Y, and Z
394 axes, and a very approximate box may be given.
395 In this case, the standard views may not be very intelligent or
396 useful, but the rendering parameters will still be satisfactory so
397 long as the overall size of the given box is close to the overall
398 size of the space.
399
400 The Zone entry windows may be manipulated in the following ways.
401 Control-U clears the current window.
402 Control-V pastes the contents of the current selection at the
403 insertion point.
404 Return moves the focus to the next window in the chain.
405
406 .Zone.Detail
407
408 The "Detail" setting indicates the relative level
409 of geometric detail in this zone.
410 If the zone is empty except for a few large pieces of furniture, a
411 "Low" setting is indicated.
412 (For an exterior zone, low detail would mean that the object is
413 relatively simple.)
414 If the zone contains a usual amount of furniture and clutter, a
415 "Medium" setting is appropriate.
416 If the zone contains a great many small objects or protrusions, a
417 setting of "High" is indicated.
418
419 This variable is used by rad to set rendering parameters that are
420 affected by the sizes of objects relative to the overall size of the
421 space.
422
423 .Zone.Indirect
424
425 The "Indirect" setting indicates how important indirect illumination
426 is in this space.
427 A setting of "0" means that most light falls directly on visible
428 surfaces, and this setting can be used in most cases.
429 A setting of "1" means that most objects are not directly
430 illuminated by light sources, but receive light only after it has
431 bounced once off some other surface, such as the ceiling.
432 Likewise, a setting of "2" means that light must reflect twice off
433 other surfaces before reaching most objects of interest.
434
435 Keep in mind that the rendering calculation increases substantially
436 with each increment to this variable, so it is a good idea to use
437 the smallest reasonable value.
438
439 .Zone.Variability
440
441 The "Variability" setting gives a qualitative indication of how
442 light varies in magnitude over surfaces in this zone.
443 In a typical direct or indirect lighting situation, this variable
444 would be set to "Low", indicating that light is fairly uniform
445 throughout the space.
446 If there are some areas that are much better lit than others, such
447 as desks with powerful tasks lights in a room with dimmer ambient
448 lighting, a "Medium" setting is appropriate.
449 If there is direct sunlight entering the room, casting bright
450 patches on some surfaces and not others, then a setting of "High" is
451 indicated.
452
453 Note that this variable speaks to the magnitude of light variations
454 more than the patterns of light.
455 It may well be that the light is casting interesting patterns such
456 as scallops on the walls or something, but as long as the variations
457 in brightness are less than an order of magnitude or so, it is a low
458 variability situation.
459 The high variability
460 example given above of direct sun entering a space corresponds to a
461 a variation in brightness of about three orders of magnitude, or
462 1,000 to 1!
463
464 .Zone.Exposure
465
466 The "Exposure" setting gives the multiplier between the initial
467 radiance values at each pixel (in watts/steradian/meter^2) to the
468 display pixel values (in the range of 0-1, where 0 is black and 1 is
469 the maximum monitor output).
470 This setting also determines the average "ambient level," which is
471 an important parameter for rendering accuracy.
472
473 There are two basic ways to compute the exposure value.
474 The first is by trial and error, where the value is adjusted up and
475 down within rview using the "e = value" command.
476 Though it sounds flaky, this is the most reliable way to set the
477 exposure (and ambient level) in general lighting situations.
478
479 The second method is using a zonal cavity approximation.
480 For this, you must estimate the total light flux entering the zone
481 from light sources and windows, and the total illuminated area.
482 (This applies to interior zones, only. For exterior zones, use the
483 value suggested by gensky in its output.)
484 In addition, you must approximate the area-weighted average
485 reflectance of the illuminated surfaces.
486 The formula then for the exposure multiplier using this information
487 is: pi*tot_area*(1-avg_refl)/(2*tot_flux*avg_refl)
488 where pi is 3.1416, tot_area is given in square meters and
489 tot_flux is given in watts.
490 (Divide total lumens by 179 lumens/watt to get watts.)
491
492 The exposure value may either be given as a positive real value, or
493 as a real value preceeded by a '+' or '-' indicating a positive or
494 negative number of f-stops (powers of two) from the original value.
495
496 If no exposure is given, pfilt will automatically compute the
497 average for each image, and a default ambient level of 10 will be
498 used for exterior zones and 0.01 for interior zones.
499
500 .Zone.Copy
501
502 The "Copy" button on the Zone screen takes all values for this
503 screen from another rad input file, replacing the current values.
504 Specifically, the rad variables "ZONE, DETAIL, INDIRECT,
505 VARIABILITY and EXPOSURE" will be copied from the named file.
506
507 All other variables will be left untouched.
508
509 .Zone.Revert
510
511 The "Revert" button is a convenient way to revert to the original
512 values in the rad input file.
513 Only the variables on the Zone screen will be affected, but any changes
514 to these variables since the last save will be lost.
515
516 .Views.Intro
517
518 This button selects the trad Views screen.
519 This screen provides a means of setting the multi-valued
520 "view" variable.
521 Each view setting is listed by name, or by number if no name has
522 been assigned.
523 To add a new view, enter a unique name and specify the view
524 options,
525 then press the "Add" or "Set Default" button.
526 If a view with the same name already exists, it is unconditionally
527 overwritten.
528 To modify a particular view, simply select it, change its name
529 and/or parameters, and press the "Change" button.
530 To remove an unwanted view, select it and press the "Delete" button.
531 To undo this action, simply press the "Add" button again.
532
533 The first view in the list is the default given to rview during
534 interactive rendering, and is the first view rendered in a batch run.
535 To change the default view, select the newly desired view and press
536 the "Set Default" button.
537 This button also acts like the "Add" button inasmuch as a new view
538 may be entered and this button will add it and make it the default
539 at the same time.
540
541 The Views screen also allows the standard view up vector to be
542 changed, as well as the root picture name and the output resolution.
543
544 .Views.List
545
546 The list box on the far left of the Views screen shows the
547 currently defined view names.
548 Clicking on any of these with the left mouse button shows the view
549 parameters and allows the view to be edited.
550
551 To change the name or options, edit the "Name" or "Options"
552 entry and click on the "Change" button.
553
554 Use the "Add" button to add a new view, which may be modified from
555 an old one by changing the name and options.
556
557 Use the "Delete" button to delete the selected view from the list.
558
559 Views are listed in the order in which they appear in
560 the rad input file.
561
562 The standard view is "X" is used if no views are specified.
563
564 .Views.Name
565
566 Each view has a unique name, which may be chosen at the user's
567 discretion or taken from a list of standard views, described below.
568 An invented name should be kept as short as possible, since it is
569 added to the picture file name along with the standard ".pic" suffix.
570
571 The standard views are specified by strings of the form
572 "[Xx]?[Yy]?[Zz]?[vlah]?".
573 (That is, an optional upper or lower case X followed by an optional
574 upper or lower case Y followed by an optional upper or lower case Z
575 followed by an optional lower case V, L, A or H.)
576 The letters indicate the desired view position, where upper case "X"
577 means maximum X, lower case "y" means minimum Y and so on.
578 The final letter is the view type, where 'v' is perspective (the
579 default), 'l' is parallel, 'a' is angular fisheye, and 'h' is
580 hemispherical fisheye.
581 A perspective view from maximum X, minimum Y would be "Xy" or
582 "Xyv".
583 A parallel view from maximum Z would be "Zl".
584 If "ZONE" is an interior zone, the standard views will
585 be inside the perimeter.
586 If it is an exterior zone, the standard views will be outside.
587 Note that the standard views are best used as starting points,
588 and additional arguments may be given after the
589 identifier to modify a standard view to suit a particular model.
590
591 .Views.Options
592
593 The "Options" entry window is where the Radiance view
594 corresponding to the selected name is given.
595 If the view is one of the standard names (described in the "Views
596 Name" section), then the options are truly optional, and will
597 modify the standard view.
598 Otherwise, it is usually necessary to specify a set of options to
599 define a view.
600
601 The simplest view specification is of the form "-vf viewfile", where
602 "viewfile" is a file created with the rview "view" command, or a
603 Radiance picture.
604 This method of naming views, although convenient, is not the best
605 since it is difficult to know exactly where such a view is by
606 seeing only its file name.
607 Also, the file may change or be moved or removed, and then the view
608 may be different than expected or gone altogether.
609
610 To add view options selected from another X11 window, select the
611 text from another window in the normal fashion, use the left mouse
612 button to click on the insertion point in the options string, then
613 use Control-V to insert the text at that point.
614 For convenience, the middle mouse button has been made
615 equivalent to Control-V in this window, but it is not the normal
616 interaction mode for trad.
617
618 Consult the rpict(1) manual page for a full description of the various
619 view options, all of which begin with "-v".
620 Just briefly, the "-vt?" option sets the view type, where "?" is
621 replaced by one of the letters "v, l, a or h", corresponding to
622 perspective, parallel, angular and hemispherical fisheye, respectively.
623 The "-vp x y z" option sets the view position (eyepoint), where "x y z"
624 is replaced by the position in 3-space.
625 The "-vd xd yd zd" option sets the view direction, where "xd yd zd"
626 is a vector pointing in the desired direction.
627 (To compute this direction from a "look-at" point, simply subtract
628 the eyepoint from the look-at point. Vector normalization is
629 unnecessary.)
630 The "-vh horiz" and "-vv vert" options set the horizontal and
631 vertical view sizes, respectively.
632 For perspective views, these correspond to full camera angles in
633 degrees.
634 For parallel views (using the "-vtl" option), they correspond to
635 image plane size in world coordinates.
636 The lesser used "-vu xd yd zd", "-vs vs" and "-vl vl" options
637 will not be discussed here.
638
639 The order of the view options is irrelevant, unless the same option
640 is given twice, in which case the last one is used.
641 Trad does not check the syntax of the view options strings, so be
642 careful!
643 In particular, make sure that each option and each argument has a
644 space between it and whatever follows.
645
646 Hitting return in the "Options" window is equivalent to pressing the
647 "Add" button followed by the "Clear" button.
648
649 .Views.Add
650
651 The view "Add" button takes the currently defined view given by the
652 "Name" and "Options" windows and appends it to the list of views.
653 If another view by the same name exists, it is removed first.
654
655 Since the view is added to the end of the "Views" list, the "Add"
656 button is a convenient way to move views to a lower-priority
657 position.
658 Simply select the view you wish to be last and press "Add".
659
660 To add a view as the first (i.e. the default) view instead of the
661 last, use the "Set Default" button.
662
663 .Views.Change
664
665 The view "Change" button deletes the currently selected view and
666 adds the currently defined view in its place, changing the name
667 and/or view options in the process.
668
669 .Views.Delete
670
671 The view "Delete" button removes the currently selected view from
672 the view list.
673
674 To undo this action, simply press the "Add" button immediately
675 afterwards, while the deleted view is still present in the edit
676 window.
677
678 .Views.Clear
679
680 The "Clear" button simply clears the "Name" and "Options" windows
681 for the convenience of entering a new view.
682 It has no effect on the rad input variables.
683
684 Note that Control-U will always clear an entry box whose cursor is
685 active.
686
687 .Views.Default
688
689 The "Set Default" button may be used to make the selected view the
690 default view for rendering.
691 This simply moves the view to the top of the list in the rad input file.
692 The default view will be the one normally rendered by rview when rad
693 is started interactively, and is the first view rendered in a batch
694 process.
695
696 A new view may be added as the default view by pressing the "Set
697 Default" button rather than the "Add" button.
698 It is never necessary to press both.
699
700 If the selected view is already the default, this button will be
701 disabled and will read "Is Default" instead of "Set Default".
702
703 .Views.Up
704
705 The standard view up vector may be set to the positive X axis (+X),
706 the positive Y axis (+Y), the positive Z axis (+Z), the negative
707 X axis (-X), the negative Y axis (-Y), or the negative Z axis (-Z).
708
709 This setting may always be overriden by the "-vu xd yd zd" option,
710 and will be altered for a particular view if it happens to be
711 parallel to the view direction.
712
713 .Views.Picture
714
715 The root picture file name is given in the "Picture" entry window.
716 To this will be added an underscore, followed by the name of
717 the particular view being rendered, followed by the ".pic" suffix.
718
719 To render pictures into a different directory than the one
720 containing the rad input file, simply precede the file name by a
721 relative or absolute directory.
722 (Do not use the tilde shorthand for home directories,
723 as it is not guaranteed to work on all systems.)
724
725 The default picture name is the root name of the rad input file.
726
727 .Views.Resolution
728
729 The final picture resolution is set in the "Resolution" entry
730 window.
731 The first entry is the X resolution (in pixels), and the second
732 (optional) entry is the Y resolution.
733 If there is only one entry, the maximum X and Y resolution will be
734 equal.
735 If a third entry is given, it is taken as the aspect ratio of the
736 destination pixels.
737 A number greater than one means that the pixels on the destination
738 device are taller than they are wide (and therefore there are more
739 of them horizontally than vertically spanning a like distance), and
740 a number less than one means the opposite.
741 An aspect ratio of zero means that the exact given X and Y
742 dimensions are to be honored, whatever the resulting pixel ratio.
743 Normally, either the X or the Y resolution is reduced as necessary
744 to maintain a specific pixel aspect ratio (1 by default).
745
746 The default value for this variable is "512".
747
748 .Views.Copy
749
750 The "Copy" button in the Views screen permits those variables
751 represented on this screen to be copied from another rad input file.
752 Specifically, the affected variables are "view, UP, PICTURE, and
753 RESOLUTION".
754
755 The original values will be lost, and all other variables will be
756 untouched.
757
758 .Views.Revert
759
760 The "Revert" button is a convenient way to revert to the original
761 values in the rad input file.
762 Only the variables on the Views screen will be affected, but any changes
763 to these variables since the last save will be lost.
764
765 .Options.Intro
766
767 This button selects the trad Options screen.
768 This screen allows the setting of various options for
769 controlling the rendering process.
770 The most general option is rendering "Quality", which determines the
771 overall accuracy and beauty of the pictures produced.
772 A separate "Penumbras" option indicates the importance of soft
773 shadows in this scene.
774 The "Ambfile" variable allows you to specify a file for sharing
775 ambient files between runs, and it is recommended that you set
776 this variable for high quality renderings.
777 The "Optfile" variable allows you to specify a separate file for
778 storing rendering options, which reduces the size of the command
779 line and makes it easier to run programs such as rtrace(1).
780 The "Report" variable may be used to specify a time interval (in
781 minutes) between progress reports.
782
783 Other windows allow the user to customize the options to oconv(1),
784 mkillum(1), rview(1) and rpict(1), and pfilt(1).
785
786 .Options.Quality
787
788 The "Quality" setting affects the overall accuracy and beauty of the
789 renderings produced.
790
791 A "Low" setting is appropriate for quick checks of scene geometry and
792 crude lighting studies.
793 No interreflection calculation will take place, regardless of the
794 setting of the "INDIRECT" variable, and other options are tuned for
795 speed over accuracy.
796 The computed picture size will exactly equal the final picture
797 size, thus some aliasing may be apparent.
798
799 A "Medium" quality setting is most often used for draft renderings, as
800 it provides a good balance between rendering time and accuracy.
801 The number of interreflections calculated will be equal to the
802 setting of the "INDIRECT" variable.
803 The computed picture size will be twice the final size, for a modest
804 degree of anti-aliasing.
805
806 A "High" quality setting is usually reserved for final renderings.
807 The number of interreflections computed will equal the value of the
808 "INDIRECT" variable plus one, to guarantee accuracy.
809 The computed picture size will be three times the final size, so
810 aliasing artifacts should be negligible.
811
812 When increasing the value of the "Quality" setting, it is usually a
813 good idea to delete the old "Ambfile", if there is one.
814 (See the "AmbDelete" topic under the current help category for
815 details.)
816
817 .Options.Penumbras
818
819 The "Penumbras" setting determines whether or not Radiance will
820 make a special effort to generate soft shadows from area light sources.
821 Since this is a potentially expensive calculation, penumbras should
822 only be switched "On" when they are really needed.
823
824 Leaving this setting "Off" does not mean that area light sources
825 will be treated as points.
826 It only means that some accuracy and possibly some smoothness
827 will be traded for speed in the shadow calculations.
828
829 .Options.Ambfile
830
831 The "Ambfile" is the file used to store Radiance ambient values for
832 later reuse in other renderings.
833 This can greatly reduce the time required to generate multiple
834 views, as well as improve the quality of a single view whenever
835 interreflections are computed.
836
837 It is strongly recommended that the user set this variable, especially
838 when the "QUALITY" variable is set to "High".
839 The usual convention is to use the root name of the rad input file,
840 followed with the ".amb" suffix.
841 It is generally not a good idea to share ambient files between
842 different zones, as the placement and accuracy of these values will
843 vary according to the location and characteristics of each zone.
844
845 .Options.AmbDelete
846
847 The "Delete" button next to the "Ambfile" window on the Options
848 screens allows you to remove the named ambient file.
849 This is usually done when a change to one or more rad variables
850 casts doubt on the accuracy of the values stored in this file.
851 In particular, increases in the variables, "DETAIL, INDIRECT,
852 VARIABILITY, EXPOSURE or QUALITY" generally invalidate this file.
853
854 If the ambient file is not empty, you will be asked to verify this
855 operation since the values may represent a significant computational
856 effort.
857
858 .Options.Optfile
859
860 The "Optfile" setting assigns a file to hold rendering options,
861 which may be a convenience when these options are reused for
862 rtrace(1) or rpiece(1), or manual invocations of rview or rpict.
863 Using an options file also reduces the size of the command line,
864 making it a little easier on the eye.
865
866 To assure that the "Optfile" contents are up-to-date, you should press
867 the "oconv" or "Script" button on the Action screen.
868
869 .Options.Report
870
871 The "Report" setting indicates the time interval (in minutes)
872 between rpict progress reports.
873 Normally, rpict runs silently, but it is often nice to know how far
874 a given rendering has progressed.
875 Normally, progress reports and errors during batch renderings
876 are sent to the error file given by the root of the rad input
877 file name followed by the ".err" suffix.
878 (See the "Errors" topic under the "Action" screen category.)
879 If you wish these reports and errors to be directed to a different
880 file, follow the time interval by a space and a file name.
881
882 No setting on this variable means do not report rendering progress.
883 A zero setting means the same thing, and may be used when a
884 separate error file is desired but progress reports are not.
885
886 .Options.Oconv
887
888 The "oconv opts" window may be used to specify any additional
889 options to the oconv(1) command used to compile the scene
890 description.
891
892 In particular, the "-f" option for creating a "frozen" octree may
893 speed rendering start-up substantially, although it makes it
894 impossible to change even material properties without
895 recompiling the scene again.
896 (The "-f" option is technically incompatible with naming
897 "materials" files on the Scene screen.)
898
899 If oconv generates a "set overflow" error, it may mean that the "-r
900 res" option is needed to increase the octree resolution.
901 See the oconv(1) man page for details.
902
903 The "-i octree" option should be used with extreme caution, as incremental
904 building of octrees is not very well supported by rad.
905 You may do it this way if you specify the input octree as one of the
906 "Objects" files on the Scene screen, but it is preferable to use the
907 UNIX make(1) utility to incrementally build the octree instead, and
908 indicate this by not specifying any illum or scene files.
909
910 .Options.Mkillum
911
912 The "mkillum opts" window may be used to specify options to the
913 mkillum(1) command, whose options are actually passed to rtrace(1).
914 These options apply only if there are one or more "Illum" files
915 named on the Scene screen.
916
917 It is very important to set mkillum options sensibly,
918 since rad does not have the intelligence to do it for you.
919
920 .Options.Render
921
922 The "render opts" window is used to specify additional options to
923 the rview(1) and rpict(1) rendering programs.
924 Most of the important parameters are computed by rad, so this
925 window is usually used to override specific parameters or to give
926 additional information, such as which materials to exclude from the
927 interreflection calculation.
928
929 .Options.Pfilt
930
931 The "pfilt opts" window is used to specify additional options to
932 the pfilt(1) picture filtering program.
933
934 Note that the "-e expval", "-x xres" and "-y yres" options are
935 already dictated by the settings of the "EXPOSURE" and "RESOLUTION"
936 variables, and should therefore be used with caution.
937
938 Also note that the setting of some pfilt options require a
939 two-pass filtering process, rather than the default single pass.
940 If no "EXPOSURE" setting is given, this is not a problem, but if a
941 value for the "EXPOSURE" variable is set as recommended, then it is
942 necessary to manually specify the "-2" option to pfilt, followed by
943 an exposure that undoes the "EXPOSURE" setting.
944 An equivalent workaround is to unset the EXPOSURE variable and
945 manually set the render option "-av V V V", where "V" is equal to
946 0.5/old_EXPOSURE.
947
948 .Options.Copy
949
950 The "Copy" button in the Options screen permits those variables
951 represented on this screen to be copied from another rad input file.
952 Specifically, the affected variables are "QUALITY, PENUMBRAS,
953 AMBFILE, OPTFILE, REPORT, oconv, mkillum, render and pfilt".
954
955 The original values will be lost, and all other variables will be
956 untouched.
957
958 .Options.Revert
959
960 The "Revert" button is a convenient way to revert to the original values
961 in the rad input file.
962 Only the variables on the Options screen will be affected, but any changes
963 to these variables since the last save will be lost.
964
965 .Action.Intro
966
967 This button selects the trad Action screen.
968 This screen is where the actual Radiance programs are
969 run, usually via rad(1).
970 The top row of buttons is used to update the octree following a
971 change to one or more input files.
972 The "rview" button starts an interactive rendering in the
973 foreground.
974 The next set of buttons provides for the control of a batch
975 rendering process, taking place in the background.
976 Finally, the bottom set of buttons allows you to preview what would
977 happen during a batch rendering, or (equivalently) make a script of
978 UNIX commands for later execution.
979
980 When the Action screen is first brought up, the message window
981 displays the current status of any batch rendering process.
982 The status must either be "No batch rendering in progress," which
983 means that as far as trad can tell a batch rendering was never
984 started, "Batch rendering stopped," meaning that there is no current
985 process but at least some views have not been rendered or are
986 out-of-date, or "Batch rendering finished," meaning that everything
987 is done.
988
989 .Action.Oconv
990
991 The "oconv" button on the Action screen may be used to manually
992 compile the scene description and bring the octree up to date.
993 It is normally not necessary to use this button, since the octree
994 will be rebuilt if appropriate prior to rendering.
995 However, if the octree is maintained by make(1) rather than rad, or
996 the octree was never created and you want trad to start a little
997 faster next time, or you just need the octree for some reason other
998 than rendering, this is the button for you.
999
1000 If you have made changes to the rad variables or the Radiance
1001 material files that invalidate the current octree or renderings but
1002 would not automatically rebuild the octree because the scene files
1003 themselves were not changed, it may be wise to use the "Force"
1004 button.
1005 In contrast, if you have made some insignificant changes to the
1006 scene files that should not make any difference to the octree or the
1007 renderings, you may want to use the "Touch" button.
1008
1009 Pressing the "oconv" button also updates the contents of the
1010 "Optfile" if one is given on the Options screen.
1011 This may be useful for computing rendering parameters for rtrace(1)
1012 or rpiece(1).
1013
1014 .Action.Force
1015
1016 The "Force" button on the Action screen
1017 causes the octree to be unconditionally rebuilt,
1018 by removing it first.
1019 This will also require all pictures to be rerendered, so only use
1020 this button if it is really necessary, i.e. if you have made
1021 some important changes to the rad
1022 variables on the Scene, Zone or Options screens, but have not
1023 changed any scene file on which the octree depends.
1024
1025 If the octree itself should not be affected by these changes, only
1026 the renderings, you may delete the faulty picture files instead from
1027 the Results screen and the ambient file (if it exists) from the
1028 Options screen.
1029
1030 .Action.Touch
1031
1032 The "Touch" button on the Action screen
1033 should be used when some insignificant change has
1034 been made to the Radiance input files, which might otherwise cause
1035 the octree to be rebuilt and the picture files to be rerendered.
1036
1037 Care should be exercised in using this button since you may have
1038 made a change that really does affect the octree in an important
1039 way.
1040 Even something as seemingly trivial as deleting an unused material
1041 will cause an unfrozen octree to become invalid and unusable.
1042
1043 Therefore, if you know the octree should be rebuilt, but you do not
1044 want to cause any of the currently rendered pictures to be redone,
1045 press the "oconv" button to bring the octree up to date, followed
1046 by the "Touch" button.
1047 (This will still cause the ambient file to be removed,
1048 unfortunately.)
1049
1050 .Action.Rview
1051
1052 The "rview" button on the Action screen starts an interactive
1053 rendering for the selected view, indicated by the menu button
1054 just to the right.
1055 Other views may be accessed within rview using the "L name"
1056 command, and new views can be added with the "V name"
1057 command.
1058 (See the rview(1) man page and the "View" topic in the current
1059 help category for more information.)
1060
1061 If the octree is out-of-date, it will be rebuilt before rendering
1062 begins.
1063
1064 .Action.View
1065
1066 The Action screen contains two menus for selecting views.
1067 The top menu, next to the "rview" button, sets the view to start
1068 with in rview, and is selected from the current view list.
1069 The second view menu, next to the "Start" button for batch
1070 rendering, selects the view or views to render in batch mode.
1071 If the special entry "ALL" is selected, then every view in the
1072 current list will be rendered if it hasn't been already.
1073
1074 The batch rendering view menu also selects the view or views
1075 to use in producing a script during a dry run.
1076
1077 .Action.Start
1078
1079 The "Start" button for batch rendering on the Action screen
1080 initiates a rad rendering process in the background using the
1081 selected view or views shown on the menu button to the right.
1082
1083 If any of the rad variables have been changed since the
1084 file was last saved, you will first be asked if you wish to save
1085 your changes before starting a background process.
1086 If you discard these changes, then the batch rendering will be
1087 conducted using the previously saved values.
1088
1089 Once a background process is going, the "Start" button is
1090 disabled, and rendering progress can be monitored by checking
1091 the error file periodically.
1092 (This file is named by the root of the rad input file followed by
1093 ".err".)
1094 When a batch process is started or already running, this button
1095 will be disabled.
1096
1097 The background process can be killed during this or later
1098 invocations of trad using the "Kill" button.
1099
1100 .Action.Kill
1101
1102 The batch rendering "Kill" button kills the
1103 background process started earlier with the "Start" button.
1104 The rad process id is taken from the first line of the error file,
1105 and this process and all its children are killed when the
1106 button is pressed.
1107
1108 So long as there is an ambient file specified in the Options
1109 screen, no data is lost by killing and restarting a batch
1110 rendering, though some new startup costs will be incurred.
1111
1112 The "Kill" button is disabled if no running batch process is
1113 detected.
1114
1115 .Action.CheckErr
1116
1117 Pressing the "Check errors" button
1118 displays the contents of the batch rendering error file, named
1119 by the root of the current rad input file followed by the ".err"
1120 suffix.
1121 This file will contain the command lines executed by rad so far,
1122 and may or may not contain additional progress reports from
1123 rpict, depending on the initial setting of the "REPORT" variable.
1124
1125 If no error file exists, this button will be disabled.
1126
1127 .Action.Script
1128
1129 The dry run "Script" button runs rad with the
1130 "-n" option so that you may see the commands that would be
1131 executed during a batch run without actually executing them.
1132 If a file is named in the window next to this button, the output
1133 will simply be written to that file.
1134 If no file is named, a temporary file is created and an editor
1135 window is opened on it.
1136
1137 Producing a dry run also writes the "Optfile" if one is specified
1138 on the Options screen.
1139 This may be useful for computing rendering parameters for rtrace(1)
1140 or rpiece(1).
1141
1142 The view or views are selected by the same menu used for
1143 batch rendering.
1144 (See the "View" topic under the current help category for more
1145 information.)
1146
1147 .Action.Edit
1148
1149 The dry run "Edit" button is used to edit the named script file
1150 created by pressing the "Script" button.
1151 If no file is named, this button is ineffective.
1152
1153 .Action.Delete
1154
1155 The "Delete" button removes the named script file, created by the
1156 "Script" button.
1157 If no file is named, or the named file does not exist, this button has
1158 no effect.
1159
1160 .Results.Intro
1161
1162 This button selects the trad Results screen.
1163 This screen permits rendered pictures to be displayed,
1164 converted to other image formats, and printed.
1165 Only finished pictures may be converted or printed, but
1166 incomplete pictures (i.e. aborted renderings or renderings in
1167 progress) may be displayed interactively.
1168
1169 The left-hand window shows a list of completed views, and the
1170 right-hand window shows views that have been started but not
1171 finished.
1172 Note that other views may not even be started, thus may not
1173 appear in either list.
1174 Also, just because a view appears on the Results screen, it does
1175 not mean that view is up-to-date with respect to the Radiance
1176 input files.
1177 (The best way currently to tell which pictures are out-of-date
1178 is to press the "Script" button on the Action screen and examine
1179 the output.)
1180
1181 .Results.Finished
1182
1183 The "Finished views" list box on the Results screen shows those
1184 renderings which have completed, whether or not they are up-to-date
1185 with respect to the Radiance input files.
1186 Select pictures in this box for display, conversion to other image
1187 formats, and/or printing.
1188 Selected pictures may also be deleted with the "Delete" button.
1189
1190 To select one or more pictures from this box, click the left mouse
1191 button on a view name, and drag it up or down to select multiple
1192 views.
1193 Shift-click also allows views to be added to the selection.
1194
1195 .Results.Unfinished
1196
1197 The "Unfinished views" list box on the Results screen shows those
1198 renderings which have not yet completed.
1199 These partial pictures may or may not be out-of-date
1200 with respect to the Radiance input files.
1201 Select pictures in this box for display or deletion.
1202 It is not possible to convert or print an unfinished picture.
1203
1204 To select one or more pictures from this box, click the left mouse
1205 button on a view name, and drag it up or down to select multiple
1206 views.
1207 Shift-click also allows views to be added to the selection.
1208
1209 .Results.Rescan
1210
1211 The "Rescan" button on the Results screen is used to update the
1212 finished and unfinished view lists, in case one or more pictures
1213 has completed since the Results screen was brought up.
1214
1215 .Results.Delete
1216
1217 The "Delete" button on the Results screen is used to remove the
1218 selected picture files from the filesystem.
1219 Verification is required before any action is taken.
1220
1221 .Results.Display
1222
1223 The "Display" button on the Results screen may be used to display
1224 the selected images using ximage(1) or any other Radiance picture
1225 display program.
1226
1227 The current display command is shown in the adjacent command window,
1228 and may be customized if necessary.
1229 (See the "DispCommand" topic in the current help category for
1230 details.)
1231
1232 .Results.DispCommand
1233
1234 The current display command in the Results screen determines how
1235 finished and unfinished Radiance pictures will be displayed.
1236 This command contains two variable fields.
1237 The first field is a signed integer, indicated by the "%+d" format.
1238 The second field is a string, indicated by the "%s" format.
1239 Both fields must appear in any display command used, and must be in
1240 this order on the command line.
1241 The first field is used to adjust the exposure of an unfinished
1242 picture, and the second field is the file name.
1243 The rest of the command is arbitrary, so long as it is understood by
1244 the system.
1245
1246 The default command is "ximage -e %+d %s >& /dev/null &", which
1247 executes ximage in the background and sends any output (including
1248 error messages) to the null device.
1249 If you don't wish ximage to run in the background, you may remove
1250 the last part of the command (" >& /dev/null &").
1251
1252 .Results.Convert
1253
1254 The "Convert" button on the Results screen converts the selected
1255 pictures to the format indicated on the menu button to the right.
1256 (See the "ConvType" topic under the current help category for
1257 details.)
1258
1259 Each finished picture is converted to the selected format and given
1260 the name indicated by the adjacent window labeled "File".
1261 (See the "ConvFile" topic under the current help category for
1262 details.)
1263
1264 .Results.ConvType
1265
1266 The image type button on the Results screen determines the
1267 destination format for converted Radiance pictures.
1268 You may choose from the list that pops up when you press this
1269 button.
1270 Often, a given format may have more than one subtype.
1271 In general, 8-bit means 8-bit color with a lookup table,
1272 B&W means 8-bit greyscale with no lookup, and 24-bit means 24-bit
1273 true color.
1274
1275 The file suffix is determined by the basic conversion type, but may
1276 be changed along with the rest of the name by editing the file name
1277 window.
1278 (See the "ConvFile" topic under the current help category for
1279 details.)
1280
1281 .Results.ConvFile
1282
1283 The image conversion file name window on the Results screen should contain
1284 a single "%s" format field, which will be replaced by the view name
1285 being converted.
1286
1287 The default name is the same as the value of the rad "PICTURE"
1288 variable, followed by a suffix appropriate to the selected file type.
1289
1290 .Results.Print
1291
1292 The "Print" button on the Results screen executes the given
1293 system command to print one copy each of the selected picture(s).
1294 This button does not work on unfinished pictures.
1295
1296 The actual command used for printing may be edited in the adjacent
1297 window.
1298 (See the "PrintCommand" topic under the current help category for
1299 details.)
1300
1301 .Results.PrintCommand
1302
1303 The print command window on the Results screen contains the system
1304 command to use in printing out finished Radiance pictures.
1305 The "%s" format field, which must appear somewhere in the command,
1306 is replaced by the selected Radiance picture file name(s).
1307
1308 The default command is "ra_ps %s | lpr", which converts the Radiance
1309 picture to a black and white PostScript file and sends it to the lpr
1310 print spooler.
1311 If your printer does not understand PostScript, or your system does
1312 not support lpr, this command must obviously be changed.