Object Type:
xvar
Description:
Object for displaying numerical values graphically. Xvar
is
subclassed from pix and can only be displayed in coredraw
subclasses.
The following parameters of the graphical display can be
used to display values in xvar:
1. Color
2-4. x,y and z offsets
5. Coordinates (morphing)
6. Line thickness. *
7. Text color *
8. Text
9. Minigraph. *
10. Surface *
11. Contour *
* Not yet available.
While these parameters can in principle be used to
simultaneously display 9 independent parameters, in practice
it gets rather confusing if more than 2 or 3 are used at a
time.
Values are specified either through messages or by directly
setting the 'values' array in the xvar. At this time 5 such
messages are permitted (VAL1, VAL2, VAL3, VAL4, VAL5).
The color_val, xoffset_val, morph_val etc.
fields are used to bind the message number to the specified
display variable. Thus setting color_val to 1 means that
message VAL1 will be used to control the color of the xvar pix.
By default all _vals are set to 0, which disables them.
The xvar pix displays values (except text and minigraph) by linear
interpolation. Every xvar has at least two child elements of class
xshape, named shape[0], shape[1], etc. These shapes determine the
extreme points for the linear interpolation. Therefore if shape[0]
has foreground color 0, and shape[1] has color 10, the range of
colors displayed would be interpolated between 0 and 10. Likewise,
if shape[0] displays a tall thin rectangle, and shape[1] a short
wide rectangle, the shapes displayed would be 'morphed' between
these two extremes. Of course, to get these effects one would have
to set the color_val and morph_val to the appropriate values.
In addition to the shapes themselves, three arrays are used to
specify
how the xvar does interpolation. As already mentioned, the 'values'
array specifies the actual values to be displayed. 'value_min'
contains the values that correspond to the lower end of the
interpolated range. Thus if value[0] was equal to value_min[0],
the parameter displayed would correspond to shape[0]. Likewise,
value_max contains the upper end of the interpolated range.
One can have multiple xshapes. In this case the interpolation
first decides which pair of shapes to use. In this version, each
pair
of shapes handles an equal range between value_min and value_max.
Having selected the appropriate pair of shapes,
the algorithm then proceeds as outlined above.
The 'text' option simply prints out the floating point value of the
appropriate message. The 'minigraph' option (which will be
implemented one of these days) displays a little graph of the
value, without any optional extras like axes.
By default, the xvar object is created along with two child shapes,
shape[0] and shape[1]. The default shapes are squares, shape[0]
being
a small one with color 0 and shape[1] a big (1x1) square in color
63.
The child shapes can have parameters set in the usual ways, but are
not displayed independently of the xvar pix. For the technically
minded, this is because their pixflags have been set to
visible_not.
Note on 'morphing': Morphing in the xvar pix is simply linear
interpolation between corresponding points. When one shape has a
different number of points from the other, then the algorithm
assumes that the missing points are [0,0,0] and does interpolation
accordingly. This may lead to peculiar effects, so usually one
uses the same number of points in all xshapes.
Author:
Upi Bhalla Caltech Dec 93
---------------------------------------------------------------------------ELEMENT PARAMETERS
DataStructure:
xvar_type [in src/Xodus/draw/xvar_struct.h
Size:
Depends on number of associated shapes.
?
Fields:
fg
Foreground color of var.
script
Script operation(s) to perform on a mouse
click. The script calls of the var are only made
if the draw determines that the var is the nearest
to the event and if the event occurred within the
bounding region of the var.
tx
Transposition distance in the x dimension. The
var is transposed (ie, displaced, offset) by this
amount.
ty
Transposition in y.
tz
Transposition in z.
pixflags
Set of flags specifying visibility,
refreshes, mouse sensitivity and many other options.
Use the 'pixflags' utility function to find out more.
varmode
Specifies the mode of operation of the xvar. Can be
one of:
shape - Does interpolation between shapes
graph - draws a minigraph (Not yet implemented)
surface - Draws a plane in 3-d, specified by 3
points in space (not yet implemented)
contour - Draws contour lines for a plane in 3-d. NYI.
colorview - Backwards compatibility hack. Uses 'shape'
mode to display boxes of different color.
boxview - Backwards compatibility hack. Uses 'shape'
mode to display boxes of different sizes.
colorboxview - Backwards compatibility hack. Default
varmode. Uses 'shape' mode to display VAL1
using both the morph and color modes for
a box.
fillboxview - Backwards compatibility hack. Uses 'shape'
mode to display filled boxes of different sizes.
value_min 1-d array with lower limits for shape parameters.
value_max 1-d array with upper limits for shape parameters.
values
1-d array with display values.
color_val Specifies message to use for color
display values. 0=disabled is default.
If you wish to cause var to change colors,
use color_val.
morph_val Specifies message to use for morphing.
If you wish to have the var change
shape, use morph_val.
xoffset_val Specifies message to use for xoffset.
If you wish to cause a var to
bounce around on the screen,
use the offset_vals.
yoffset_val Specifies message to use for yoffset.
zoffset_val Specifies message to use for zoffset.
text_val
Specifies message whose value should
be printed out.
textcolor_val
Specifies message which determines
the color of the text.
linethickness_val Specifies message determining the
line thickness used in the var.
sizescale Rescales all the shapes. The default
shapes have a size of 1.
--------------------------------------------------------------------------SIMULATION PARAMETERS
Function:
XVar [in src/Xodus/draw/xvar.c]
Classes:
gadget output
Actions:
PROCESS: Redo interpolation and display.
RESET:
Required when changing child xshapes.
CREATE: Automatically creates 2 child xshapes.
XUPDATE: update internal fields when
displayed widget is changed.
B1DOWN:
Invoked when mouse Button 1 is pressed.
B2DOWN:
Invoked when mouse Button 2 is pressed.
B3DOWN:
Invoked when mouse Button 3 is pressed.
ANYBDOWN: Invoked when any mouse button is pressed.
B1DOUBLE: Invoked on a double click on mouse button 1.
B2DOUBLE: Invoked on a double click on mouse button 2.
B3DOUBLE: Invoked on a double click on mouse button 3.
XOCOMMAND: an action that can invoke the functions
in the 'script' field
XODROP: Called when a another pix is dropped onto this one.
XODRAG: Called when the mouse is clicked on this pix, and
the mouse moves while the mouse button is held down.
XOWASDROPPED: Called after this pix has been dropped onto
another one.
Messages:
VAL2
VAL3
VAL4
VAL5
COORDS x y z
VAL1 data
data
data
data
data
All messages can contain values for any display parameter.
--------------------------------------------------------------------------Notes:
Can only be displayed in a coredraw widget subclass.
The xvar performs the interpolation between shapes and
redraws them on every clock tick.
Example:
See also:
xview, xshape