propertySetter {rgl}

R Documentation

Write HTML/Javascript code to control a WebGL display.

Description

propertySlider writes out HTML code to control WebGL displays on the same page via a slider; par3dinterpSetter and propertySetter return Javascript code to be used in HTML controls.

Usage

propertySlider(setter = propertySetter,
             minS = min(param), maxS = max(param), step = 1, init = minS, 
	     labels = displayVals(sliderVals), 
	     id = basename(tempfile("input")), name = id,
	     outputid = paste0(id, "text"),
	     ...) 
	     
propertySetter(values, entries, properties, objids, prefixes = "",
               param = seq_len(NROW(values)), interp = TRUE, digits = 7) 
               
par3dinterpSetter(fn, from, to, steps, subscene, omitConstant = TRUE, ...)

Arguments

setter	A function to write Javascript code, or its output, or a list containing several of these.
minS, maxS, step, init	Slider values to be displayed.
labels	Labels to display for each slider value. The defaults are calculated using internal variables. If NULL, no labels will be shown.
id	The id of the input control that will be generated.
name	The name of the input control that will be generated.
outputid	The id of the output control that will display the slider value, or NULL for none.
...	See Details below.
values	An array of values; rows correspond to slider positions.
entries, properties, objids, prefixes	Vectors describing the columns of values. See the details below.
param	Parameter values corresponding to each row of values.
interp	Whether to interpolate values. If FALSE, the Javascript function will expect non-negative integer values.
digits	How many significant digits to emit in the Javascript code.
fn	A function returned from par3dinterp.
from, to, steps	Values where fn should be evaluated.
subscene	Which subscene's properties should be modified?
omitConstant	If TRUE, do not set values that are constant across the range.

Details

The ... parameters to propertySlider will be passed to setter if the latter is a function, otherwise ignored.

The ... parameters to par3dinterpSetter will be passed to propertySetter.

propertySetter is a low-level general purpose function for modifying properties of objects in the scene. It is mainly for internal use. propertySlider uses it to generate Javascript for a slider control to manipulate those properties. par3dinterpSetter uses it to set parameters corresponding to values produced by the result of par3dinterp.

The rows of the values matrix correspond to different settings for numeric properties. The columns are values to insert into those properties.

Argument entries gives the numeric (zero based) index into the Javascript property named by properties, for the object id objids, in the display with prefix prefixes. All of these may be vectors, corresponding to the columns of values. All but entries will be recycled to the appropriate length; its length needs to match the number of columns in values.

There are two modes for determining the values to substitute. In the simplest mode (interp = FALSE in propertySetter), each row of values corresponds to a location for the slider, and the values are simply copied into place. This requires that param, min, max and step take on their default values.

In other cases, linear interpolation is used between successive rows of values, with extrapolation outside the range of param repeating the first or last row. param should then contain the values that correspond to exact rows.

In both cases, param must be a strictly increasing vector.

Value

propertySlider prints the full code to generate the control, and returns the id of the control that was generated.

propertySetter returns a single element character vector containing the Javascript source for a function to set the appropriate properties. It does not assign the function to a variable or include any of the HTML wrapper text that propertySlider adds.

The character vector has class "propertySetter", and an attribute named "env" which gives access to the local environment where it was created, so for example attr(value, "env")$prefixes will give access to the prefixes argument if value was produced by "propertySetter".

Author(s)

Duncan Murdoch

See Also

writeWebGL. clipplaneSlider makes use of propertySlider.

ageSetter can be used as the setter argument to propertySlider to modify objects according to a linear (age) scale.

Examples

# Just the setter function
cat(propertySetter(1:4, entries = 12, properties = "values", objids = 13))

# A 4-position slider
propertySlider(values = 1:4, entries = 12, properties = "values", objids = 13, interp = FALSE)

# A 10-position slider interpolating the 4-position slider
propertySlider(values = 1:4, entries = 12, properties = "values", objids = 13,
               step = (4-1)/9)
               
# The userMatrix interpolation from example(play3d)
M <- r3dDefaults$userMatrix
fn <- par3dinterp(time = (0:2)*0.75, userMatrix = list(M,
                                     rotate3d(M, pi/2, 1, 0, 0),
                                     rotate3d(M, pi/2, 0, 1, 0) ) )
cat(par3dinterpSetter(fn, 0, 3, steps=10))

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