func plot_cone(α float64, preservePrev bool) {
nu, nv := 11, 21
l := 1.2
r := math.Tan(α) * l
S, T := utl.MeshGrid2D(0, l, 0, 2.0*PI, nu, nv)
X := la.MatAlloc(nv, nu)
Y := la.MatAlloc(nv, nu)
Z := la.MatAlloc(nv, nu)
u := make([]float64, 3)
v := make([]float64, 3)
L := rot_matrix()
for j := 0; j < nu; j++ {
for i := 0; i < nv; i++ {
u[0] = S[i][j] * r * math.Cos(T[i][j])
u[1] = S[i][j] * r * math.Sin(T[i][j])
u[2] = S[i][j]
la.MatVecMul(v, 1, L, u)
X[i][j], Y[i][j], Z[i][j] = v[0], v[1], v[2]
}
}
pp := 0
if preservePrev {
pp = 1
}
plt.Wireframe(X, Y, Z, io.Sf("color='b', lw=0.5, preservePrev=%d", pp))
}
func plot_convex(level float64, preservePrev bool) {
X, Y := utl.MeshGrid2D(0, 1, 0, 1, NU, NV)
Z := la.MatAlloc(NV, NU)
for j := 0; j < NU; j++ {
for i := 0; i < NV; i++ {
Z[i][j] = level - math.Sqrt(X[i][j]) - math.Sqrt(Y[i][j])
if Z[i][j] < -0.01 {
Z[i][j] = math.NaN()
}
}
}
pp := 0
if preservePrev {
pp = 1
}
plt.Wireframe(X, Y, Z, io.Sf("color='k', lw=0.5, preservePrev=%d", pp))
}
func plot_sphere(preservePrev bool) {
R := 1.0
U, V := utl.MeshGrid2D(0, PI/2.0, 0, PI/2.0, NU, NV)
X, Y, Z := la.MatAlloc(NV, NU), la.MatAlloc(NV, NU), la.MatAlloc(NV, NU)
for j := 0; j < NU; j++ {
for i := 0; i < NV; i++ {
X[i][j] = R * math.Cos(U[i][j]) * math.Sin(V[i][j])
Y[i][j] = R * math.Sin(U[i][j]) * math.Sin(V[i][j])
Z[i][j] = R * math.Cos(V[i][j])
}
}
pp := 0
if preservePrev {
pp = 1
}
plt.Wireframe(X, Y, Z, io.Sf("color='k', lw=0.5, preservePrev=%d", pp))
}
func plot_superquadric(a, b, c float64, preservePrev bool) {
A, B, C := 2.0/a, 2.0/b, 2.0/c
R := 1.0
U, V := utl.MeshGrid2D(0, PI/2.0, 0, PI/2.0, NU, NV)
X, Y, Z := la.MatAlloc(NV, NU), la.MatAlloc(NV, NU), la.MatAlloc(NV, NU)
for j := 0; j < NU; j++ {
for i := 0; i < NV; i++ {
X[i][j] = R * cosX(U[i][j], A) * sinX(V[i][j], A)
Y[i][j] = R * sinX(U[i][j], B) * sinX(V[i][j], B)
Z[i][j] = R * cosX(V[i][j], C)
}
}
pp := 0
if preservePrev {
pp = 1
}
plt.Wireframe(X, Y, Z, io.Sf("color='k', lw=0.5, preservePrev=%d", pp))
}
func plot_plane(preservePrev bool) {
N := []float64{1, 1, 1} // normal
P := []float64{0.5, 0, 0} // point on plane
d := -N[0]*P[0] - N[1]*P[1] - N[2]*P[2]
X, Y := utl.MeshGrid2D(0, 0.5, 0, 0.5, NU, NV)
Z := la.MatAlloc(NV, NU)
for j := 0; j < NU; j++ {
for i := 0; i < NV; i++ {
Z[i][j] = (-d - N[0]*X[i][j] - N[1]*Y[i][j]) / N[2]
if Z[i][j] < -0.01 {
Z[i][j] = math.NaN()
}
}
}
pp := 0
if preservePrev {
pp = 1
}
plt.Wireframe(X, Y, Z, io.Sf("color='k', lw=0.5, preservePrev=%d", pp))
}