PICTURE IT
README File
April 1994


This CADKEY README.PIC  file contains information about Picture It that 
became available after the manuals went to press. 

Picture It is a utility that is not a modeling tool, but rather a 
modeling aid.


OPERATING RESTRICTIONS

Picture It can run up to seven times slower on the UNIX platform than it 
does in DOS.

Processing models with over 1500 entities is not recommended because of 
extremely lengthy processing times.

Picture It does not understand, and therefore cannot render, the solids 
primitives generated by the SP.CDX utility.


PART PREPARATION

Lines must connect to end points and end points must be connected by lines. 
This is important when using polylines and splines.

Recognition of two-connected geometry is haphazard. If you don't like the 
result convert it to three-connected geometry.

Picture It will not automatically mesh a three-sided boundary. If you mesh 
it yourself the results may still be unsatisfactory. The best course is to 
make the three-sided boundary into a four-sided boundary.

Beware of two-connect situations, they are everywhere and must be modeled 
specifically for Picture It. This is covered in detail in the CADKEY Picture 
It Manual.

Picture It will not recognize FastSurf surfaces in any display model.


CONTROLLING STARTUP

If the Picture It toolbar is not visible when you exit CADKEY, then it will 
not be visible when CADKEY is restarted. Picture It remembers whether it 
was active or not and assumes the same configuration when restarted.


LEVELS

Mask Level - The Mask Level is ignored by Picture It. It will temporarily 
set it to 0 when doing its work, and restore its value when done. Any 
geometry that is displayed it will be recognized and rendered.

Level 256 - Picture It uses level 256 as a scratch level when printing and 
when performing filled renderings. Geometry on level 256 may be affected.


RENDERING

Some designs are rendered wrong, giving the appearance of the inside of the 
part. This will be fixed in a future release.

If you find that a rendering is corrupted by "tracks" left behind by the 
cursor, render with the cursor moved out of the render area.

When Arc Seg and Object Mask are not set properly a correctly modeled part 
can render incorrectly, not at all, or greatly lengthen processing time.

0 Perspective is no distortion in a rendering's perspective; 100 is the 
maximum distortion. The greater the Perspective value, the greater the 
perspective distortion.

Picture It will assign a level descriptor to any saved rendering. It will 
overwrite previous level descriptors.

If you are having a problem selecting an entity after processing press the 
Regen button in the status area. If the problem still exists save your part 
and reload it.


Hidden Rendering

Use of gray lines in a model will make the hidden line representation 
difficult to understand because hidden lines appear in gray. 

Pop Throughs - Sometimes a line that should be hidden in a Hidden rendering 
will be visible. You can save to a level and remove the extra line by hand.

Note that Perspective only applies to Hidden and Dashed renderings.


Dashed Rendering

Pop Throughs - Sometimes a line that should be hidden in a Dashed rendering 
will be visible. You can save to a level and remove the extra line by hand.

Note that Perspective only applies to Hidden and Dashed renderings.


Filled Rendering

The palette used during a Filled Rendering is different from that used by 
CADKEY.  A close match will result if red, green, blue, cyan, magenta, 
and white are selected for the filled colors.  

When filled rendering is used, polygons on level 256 can be deleted.

Filled renderings will not look the same after you press RETURN. [Ctrl]-[R] 
will redraw the wire-frame model.

If you save a Filled rendering Picture It changes your palette. Use FILES, 
CDE, EXECUTE and select pi_default_palette to correct the palette.


Smooth Rendering

Smooth renderings will not look the same after you press RETURN. [Ctrl]-[R] 
will redraw the wire-frame model.


Orphan Rendering

If you select Orphans from the Render menu and there are no orphans, pop-up 
box appears to let you know. 

An orphan in Picture It, Rev. 2.0 is the same as unrecognized geometry in 
Picture It, Rev. 1.0.


MASS PROPERTIES

The dynamic Mass Property information may be incorrect.

Totals in Mass Properties: Area, Volume, and Mass are totaled in the 
Mass Properties output file. They will be available on the screen in a 
future relase.

If two objects share a common boundry, the Mass Property calculation may 
be wrong.

The Mass Properties calculation requires three- or four-sided polygons.  
If Poly Vert is set to some value greater than 3, existing boundaries will
be split until the constraint is met.  This automatic split also happens
before polygons are written to an SLA file.


ESCAPE TO QUIT

ESC is only observed when it is safe to stop processing. Which means that 
ESC may not take effect immediately and when recognised it may only cause 
the current step in the processing to be skipped.  Repeated ESCapes may 
be needed.


CYLINDERS

The cylinder idiom can only be constructed using closed circles, conics, and
splines.  The down-connect in the cylinder will be treated as a straight
line and must be at an end point.


Error Messages: SNH

Some error messages end with the three letters, SNH, meaning "Should Never 
Happen". This message indicates that your part has some feature which was 
not anticipated or probable. Such a part file is useful for development since 
it can be used as a test case to experiment with and expand the range of 
solvable graphs. If you get a SNH error, please submit the part file with a 
defect report to CADKEY.


POLYGON INPUT

Direct input of polygons, formerly called "literal poylygons" is no 
longer supported. 


SPACEBALL

Picture It is aware of the Spaceball. If you have a rendering on the screen, 
and the prompt that gives the options to Print, Save or Continue is visible,
then manipulating the Spaceball produces a new view followed by a rendering 
in the new view.

To use the Spaceball with Picture It, you must load the Picture It CDE after
loading the Spaceball CDE.

SLIDE FUNCTION

The slide function is not available while Picture It is processing or 
displaying a menu or prompt.


BIRDS EYE AND WORMS EYE

Picture It disables the Display List while it is processing, so Birds Eye 
and Worms Eye are not available at that time.


