CG


center of gravity

animate
coe
fac
illum          image
matrix
secx          secy
traj
vertex          vol
See also

CG animate

CG animate vol(id)

        Returns the last 3 positions of the volume id (if yes dynamic)).

CG coe

CG(p1,p2, ...)coe(c1,c2,...)

        Returns the centroide of points pi=xi,yx,zi with coefficients ci.

CG(p1,p2, ...)coe normal

        Returns the centroide of points pi=xi,yx,zi with normalized coefficients.

CG illum

CG illum image(id)

        Returns the center of gravity of the pixels of the image id.
Options:
illum(r1,v1,b1,r2,v2,b2): returns the center of gravity of pixels color between (R1, G1, B1) and (r2, v2, b2) of the image id.

CG fac

CG fac(f)vol(id)

        Returns the center of gravity of the facet f-number of the volume id.
Options:
matrix ou anc: reflects the transformations of type matrix.

image CG

CG image(id)

       Returns the center of gravity image's id pixels.

Options:
displ(r,v,b)poi(x1,y1,x2,y2)radius(r): a rectangle side r (5default) and color (r,v,b) is displayed at the CG of window (x1,y1,x2,y2).
Without this option a threshold is computed in comparison with the average luminance.
displ(r1,v1,b1,r2,v2,b2)poi(x1,y1,x2,y2): displays the CG of the full image with color (r1,v1,b1) (red default), and the CG of sub images in color (r2,v2,b2) (green default).
CG(n): returne the n*n+1 CG:
       gc=image(id)CG: CG of full image.
       gij=image(id)CG secx(x1,x2)secy(y1,y2): CG of sub image (i,j) i and j in [0,n[.
So:
image(id)CG(2) retourne:
       gc=image(id)CG: CG of full image.
       gbg=image(id)CG secx(0,.5)secy(0,.5): CG of the lower left sub image.
       gbd=image(id)CG secx(.5,1)secy(0,.5): CG of the top left sub image.
       ghg=image(id)CG secx(0,.5)secy(.5,1): CG of the top left sub image.
       ghd=image(id)CG secx(.5,1)secy(.5,1): CG of the top right sub image.
format("f"): according to the format "f":
secx(x1,x2)secy(y1,y2): of window (x1,y1,x2,y2) (origine lower left corner).
normal: normalized coordinates between 0.0 and 1.0.
precision(p): the threshold is around p (0.5 default).

Examples:
CG image(id)
       Reurns the CG of pixels luminance > 0.5 of image id.
CG image(id)precision(.25)
        Returns ethe le CG of pixels luminance > 0.25 of image id.
CG image(id)format("RGB")precision(.2,.4,.6)
        Returns the CG of pixels color > (0.2,0.4,0.6) of image id.

CG matrix

CG matrix vol(id)

        Returns the center of gravity of volume id when transformed by its matrix.

CG secx

CG secx vol(id)

        Returns the centers of gravity of the x sections of volume id.

CG secx(s)vol(id)

        Returns the centers of gravity of the x sections s-number of volume id.
Options:
normal: s is normalized between 0 and 1.

CG secy

CG secy vol(id)

        Returns the centers of gravity of the y sections of volume id.

CG secy(s)vol(id)

        Returns the centers of gravity of the y sections s-number of volume id.
Options:
normal: s is normalized between 0 and 1.

CG traj(id)

        Returns the center of gravity of trajectory id.
Options:

CG vertex

CG vertex(s)obj(id)

        Returns the center of gravity of the vertices s-numbers the object id of type obj.

CG vol

CG vol(id)

        Returns the center of gravity of points referenced in the facets of the volume id.
Options:
abs: returns the center of gravity of all points in the volume id.
anc: returns the center of gravity of poi anc of volume id.
matrix: transformed by the volume id matrix.
vol(id1,id2,...): returns the center of gravity of volumes idi.
coe(c1,c2,...): returns average(sum(ci*(CG vol(idi)))).

See also:

CG(expr)
displ CG (fac) vol