func main() {
// vtk scene
scene := vtk.NewScene()
// setting the scene up
scene.WithPlanes = false
scene.HydroLine = false
scene.AxesLen = 2
// function
r := 1.0 // radius
fcn := func(x []float64) (f, vx, vy, vz float64) {
f = x[0]*x[0] + x[1]*x[1] + x[2]*x[2] - r*r
return
}
// iso-surface object
surface := vtk.NewIsoSurf(fcn)
surface.AddTo(scene) // add surface to scene
// add arrow
arrow := vtk.NewArrow()
arrow.V = []float64{2, 2, 2}
arrow.AddTo(scene) // add arrow to scene
// filename for saving figure on exit
scene.Fnk = "/tmp/example01"
scene.SaveOnExit = true
// add to scene and show in interactive mode
scene.Run()
}
func main() {
// create a new VTK Scene
scn := vtk.NewScene()
scn.Reverse = true // start viewing the negative side of the x-y-z Cartesian system
// parameters
M := 1.0 // slope of line in p-q graph
pt := 0.0 // tensile p
a0 := 0.8 // size of surface
// limits and divisions for grid generation
pqth := []float64{pt, a0, 0, M * a0, 0, 360}
ndiv := []int{21, 21, 41}
// cone symbolising the Drucker-Prager criterion
cone := vtk.NewIsoSurf(func(x []float64) (f, vx, vy, vz float64) {
p, q := calc_p(x), calc_q(x)
f = q - M*p
return
})
cone.Limits = pqth
cone.Ndiv = ndiv
cone.OctRotate = true
cone.GridShowPts = false
cone.Color = []float64{0, 1, 1, 1}
cone.CmapNclrs = 0 // use this to use specified color
cone.AddTo(scn) // remember to add to Scene
// ellipsoid symbolising the Cam-clay yield surface
ellipsoid := vtk.NewIsoSurf(func(x []float64) (f, vx, vy, vz float64) {
p, q := calc_p(x), calc_q(x)
f = q*q + M*M*(p-pt)*(p-a0)
return
})
ellipsoid.Limits = pqth
cone.Ndiv = ndiv
ellipsoid.OctRotate = true
ellipsoid.Color = []float64{1, 1, 0, 0.5}
ellipsoid.CmapNclrs = 0 // use this to use specified color
ellipsoid.AddTo(scn) // remember to add to Scene
// illustrate use of Arrow
arr := vtk.NewArrow() // X0 is equal to origin
arr.V = []float64{-1, -1, -1}
arr.AddTo(scn)
// illustrate use of Sphere
sph := vtk.NewSphere()
sph.Cen = []float64{-a0, -a0, -a0}
sph.R = 0.05
sph.AddTo(scn)
// start interactive mode
scn.SaveOnExit = true
scn.Fnk = "/tmp/gosl/vtk_isosurf01"
scn.Run()
}
func main() {
α := 0.45
κ := 2000.0
SQ3 := math.Sqrt(3.0)
M := 3.0 * SQ3 * α
qy0 := SQ3 * κ
sinφ := 3.0 * M / (M + 6.0)
φrad := math.Asin(sinφ)
φdeg := φrad * 180.0 / math.Pi
cosφ := math.Cos(φrad)
tanφ := math.Tan(φrad)
c := qy0 * tanφ / M
pt := c / tanφ
κ_ := 6.0 * c * cosφ / (SQ3 * (3.0 - sinφ))
io.Pforan("α = %v\n", α)
io.Pforan("κ = %v (%v)\n", κ, κ_)
io.Pforan("φ = %v\n", φdeg)
io.Pforan("c = %v\n", c)
io.Pforan("M = %v\n", M)
io.Pforan("qy0 = %v\n", qy0)
scn := vtk.NewScene()
scn.AxesLen = c * SQ3
pqth := []float64{-pt, pt, 0, pt * M * 1.2, 0, 360}
ndiv := []int{21, 21, 41}
cone1 := vtk.NewIsoSurf(func(x []float64) (f, vx, vy, vz float64) {
I1, sqJ2d := calc_I1(x), calc_sqJ2d(x)
f = sqJ2d - α*I1 - κ
return
})
cone1.Limits = pqth
cone1.Ndiv = ndiv
cone1.OctRotate = true
cone1.GridShowPts = false
cone1.Color = []float64{1, 0, 0, 1.0}
cone1.CmapNclrs = 0
cone1.AddTo(scn)
cone2 := vtk.NewIsoSurf(func(x []float64) (f, vx, vy, vz float64) {
p, q := calc_p(x), calc_q(x)
f = q - M*p - qy0
return
})
cone2.Limits = pqth
cone2.Ndiv = ndiv
cone2.OctRotate = true
cone2.GridShowPts = false
cone2.Color = []float64{0, 0, 1, 0.5}
cone2.ShowWire = true
cone2.CmapNclrs = 0
cone2.AddTo(scn)
arr := vtk.NewArrow()
arr.X0 = []float64{-pt / SQ3, -pt / SQ3, -pt / SQ3}
arr.V = []float64{pt, pt, pt}
arr.Color = []float64{0, 1, 0, 1}
arr.CyliRad = κ / 10
arr.ConeRad = 1.2 * κ / 10
arr.ConePct = 0.5
arr.AddTo(scn)
scn.Run()
}
