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tdstrs

Sets the values defining a selected rendering style (for use with selected TDPACK routines).

Available in version 4.3.1 and later.

Prototype

	procedure tdstrs (
		render_index    [1] : integer,  
		bot_fill_index1 [1] : integer,  
		bot_fill_index2 [1] : integer,  
		top_fill_index1 [1] : integer,  
		top_fill_index2 [1] : integer,  
		bot_line_index  [1] : integer,  
		top_line_index  [1] : integer,  
		draw_edge       [1] : integer,  
		udist           [1] : float,    
		vdist           [1] : float,    
		wdist           [1] : float     
	)

Arguments

render_index

An input integer scalar specifying the index of the rendering style to be changed. See the low-level "Rendering-Style Arrays" section for descriptions of the internal parameters defining the rendering styles.

bot_fill_index1
bot_fill_index2

Color indices specifying a range of colors to be used for the "bottom" side of a surface (where function values are less than the value on the surface).

If bot_fill_index1 is negative, filling of triangles seen from the "bottom" is turned off. If bot_fill_index1 is zero or greater, but bot_fill_index2 is less than or equal to it, the color with index bot_fill_index1 is used. If bot_fill_index1 is zero or greater and bot_fill_index2 is greater than bot_fill_index1, then a range of color indices is specified; colors near the beginning of that range are used for triangles that are nearly perpendicular to the line of sight, while colors near the end of that range are used for triangles more nearly parallel to the line of sight. (Normally, one should make triangles perpendicular to the line of sight lighter than those parallel to the line of sight.)

top_fill_index1
top_fill_index2

Color indices specifying a range of colors to be used for the "top" side of a surface (where function values are greater than the value on the surface).

If top_fill_index1 is negative, filling of triangles seen from the "top" is turned off. If top_fill_index1 is zero or greater, but top_fill_index2 is less than or equal to it, the color with index top_fill_index1 is used. If top_fill_index1 is zero or greater and top_fill_index2 is greater than top_fill_index1, then a range of color indices is specified; colors near the beginning of that range are used for triangles that are nearly perpendicular to the line of sight, while colors near the end of that range are used for triangles more nearly parallel to the line of sight. (Normally, one should make triangles perpendicular to the line of sight lighter than those parallel to the line of sight.)

bot_line_index
top_line_index

Color indices specifying colors to be used for lines drawn on the "bottom" or "top" side of a surface. If either one is set to a negative value, the drawing of those lines is turned off.

draw_edge

A flag, which if set to non-zero, turns on the drawing of the edges of the individual triangles into which surfaces have been decomposed.

udist
vdist
wdist

Float scalars representing the distances between slices in the U, V, and W directions, respectively. If a given value is zero, the associated slice lines are not drawn.

Description

This routine is part of the low-level TDPACK package, which is a group of Fortran and C callable routines for projecting objects from a 3-dimensional coordinate system having U, V, and W axes to a 2-dimensional projection plane having X and Y axes and/or for drawing the projections of those objects. This can be referred to somewhat loosely as "drawing objects in three dimensions".

Please see the documentation on TDSTRS for a full description of this procedure.

Examples

The following code produces a sample 3D scatter plot:

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"

; 
; Function for generating random data.
;
function dsrnd1(ifrst,nextn)
begin
  MPLIER = 16807
  MODLUS = 2147483647
  MOBYMP = 127773
  MOMDMP = 2836
  JSEED  = 123456789

  if (ifrst .eq. 0) then
    nextn = JSEED
    ifrst = 1
  end if

  hvlue = nextn / MOBYMP
  lvlue = nextn % MOBYMP
  testv = MPLIER*lvlue - MOMDMP*hvlue

  if (testv .gt. 0) then
    nextn = testv
  else
    nextn = testv + MODLUS
 end if

  return((1.*nextn)/(1.*MODLUS))
end


begin
 N       = 1331
 NEAREST =  500
 MTRI    = 150000
 FARTHER = N - NEAREST

;
; Create our input and work arrays.
;
  x = new(N,float)
  y = new(N,float)
  z = new(N,float)
  rtri = new((/MTRI,10/),float)
  rtwk = new((/MTRI,2/),float)

;
; Fill up the dummy input arrays.
;
  ifrst = 0
  nextn = 0
  do i = 0,N-1
    x(i) = dsrnd1(ifrst,nextn)    
    y(i) = dsrnd1(ifrst,nextn)
    z(i) = dsrnd1(ifrst,nextn)    
  end do

;
;  Specify the reference point from which we want to find the NEAREST
;  nearest points.
;
  px = 0.5
  py = 0.5
  pz = 0.5

  wks = gsn_open_wks("ps","scatter")  

;
; Set some TDPACK parameters and initialize. These four are viewport
; specifiers.
;
  tdsetp("VPB", 0.09)
  tdsetp("VPT", 0.99)
  tdsetp("VPL", 0.11)
  tdsetp("VPR", 1.00)

  tdinit((/4.6, 3.0, 3.3/), (/0.5, 0.5, 0.5/), (/0.5, 0.5, 2.7/), 0.)

;
;  Set up some colors using the standard TDPACK entry for that.
;
  tdclrs(wks, 1, 0., 0.8, 8, 37, 8)

;
;  Define style indices for shades of gray, green, and red.
;
  tdstrs(1,  8, 37,   8,  37, 1, 1, 0, 0.05, 0.05, 0.)
  tdstrs(3,  8, 37,  68,  97, 1, 1, 0, 0.05, 0.05, 0.)
  tdstrs(4,  8, 37,  98, 127, 1, 1, 0, 0.05, 0.05, 0.)

;
;  Store the indices of the nearest points in npts and the complement
;  of that set (with respect to the entire input dataset) in mpts.
;
  npts = new(NEAREST,integer)
  mpts = new(FARTHER,integer)

  npts(0) = shgetnp(px,py,pz,x,y,z,0)
  do i=2,N
    if (i .le. NEAREST) then
      npts(i-1) = shgetnp(px,py,pz,x,y,z,1)
    else
      mpts(i-1-NEAREST) = shgetnp(px,py,pz,x,y,z,1)
    end if
  end do

;
;  Plot the near points in green.
;
  ntri = 0
  dotsize = 0.02
  do i = 0, NEAREST-1
    tdmtri(-5, (/x(npts(i)-1), y(npts(i)-1), z(npts(i)-1)/), dotsize, \
           rtri, ntri, 4, (/0.,0.,0./),(/1.,1.,1./))
  end do

;
;  Plot the farther points in gray.
;
  do i = 0, FARTHER-1
    tdmtri(-5, (/x(mpts(i)), y(mpts(i)), z(mpts(i))/), dotsize, \
           rtri, ntri, 1, (/0.,0.,0./),(/1.,1.,1./));
  end do

;
;  Mark the reference point in red.
;
  tdmtri(-5,(/px,py,pz/),1.2*dotsize,rtri,ntri,3,(/0.,0.,0./),(/1.,1.,1./))

;
;  Order and draw triangles.
;
  itwk = tdotri(rtri, ntri, rtwk, 0)
  tddtri(wks,rtri, ntri, itwk)

;
;  Draw a box around the perimeter.
;
  tdgrds(wks,(/0., 1., 0./), (/1., 0., 1./), (/-1., -1., -1./),11,0)
  tdgrds(wks,(/0., 1., 0./), (/1., 0., 1./), (/-1., -1., -1./),11,1)

  frame(wks)

end

Also see examples 3, 4, and 5 on the three-dimensional graphics applications page.

tdstrs

Prototype

Arguments

Description

See Also

Examples