From f78ca8404d6835f119a369ec2235e9ae86121a30 Mon Sep 17 00:00:00 2001
From: Peter Corke <peter.i.corke@gmail.com>
Date: Mon, 17 Aug 2026 13:53:33 +1000
Subject: [PATCH 1/3] fix: restore pvplus.py, fix pyvista API drift, drop
 rvcprint from figure scripts

Fixes #20. tools/pvplus.py was a symlink to a path on the reporter's old
machine (/Users/corkep/Dropbox/.../frames.py) that never existed in this
repo or anywhere accessible -- every figures/**/*.py script that did
`import pvplus` was broken for anyone but the original author, and only
by cwd accident even then.

Recovered the file's content (three near-identical copies existed, all
but one line identical) and placed it at RVC3/tools/pvplus.py instead of
bare tools/ or figures/3d/: it's imported by ~40 scripts spread across
figures/3d/ and multiple figures/code/chapterN/ subdirectories, and
RVC3.tools is already a real, declared, pip-installable package -- the
only placement that resolves for every consumer via a normal
`pip install -e .` dev setup, with no PYTHONPATH tweaking needed.

Swapped `import pvplus` -> `from RVC3.tools import pvplus` in all 40
consuming scripts (mechanical, one line each -- every pvplus.xxx(...)
call site is unchanged since the bound name doesn't change). Also fixed
outfile()'s hardcoded personal absolute path to derive from the calling
script's own location -- same class of bug as the original issue, no
reason to reintroduce it.

Testing this surfaced two more real, pre-existing issues:
- pyvista's PolyData.transform() now requires an explicit inplace=
  kwarg (used to default to True) -- added it at all 7 call sites in
  pvplus.py so it actually runs against a current pyvista install.
  Several individual figure scripts have their own local .transform()
  calls with the same issue; left those alone, out of scope here.
- Several scripts import a book-production image-export helper
  (rvcprint) that's either equally broken (bare `import rvcprint` /
  `from rvcprint import outfile`) or just unnecessary for what we're
  testing here. Commented it out (import + the screenshot-path usage)
  in the ~10 pvplus-consuming scripts that referenced it, per
  discussion -- it's book-production plumbing, not needed to exercise
  the actual figure-generation logic.

Adds a `figures` optional-dependency extra (pyvista, vtk, pillow) to
pyproject.toml, since none of this was previously declared anywhere --
`pip install -e ".[figures]"` is now the documented way to get set up
for regenerating book figures.

## Test plan
- All 40 modified scripts pass `py_compile`
- Ran 9 of the pvplus-consuming scripts end-to-end (add_frame, ribbon,
  axis, add_ellipsoid, ellipsoid_3d, add_frame2 all exercised), all
  exit 0
- 3 more (fig2_15.py, fig2_16.py, fig9_17.py in figures/code/) open a
  real on-screen render window since they don't set off_screen=True --
  confirmed rendering correctly by eye, not run to completion
  headlessly
---
 RVC3/tools/pvplus.py                          | 441 ++++++++++++++++++
 figures/3d/fig2_14.py                         |   4 +-
 figures/3d/fig2_16.py                         |   4 +-
 figures/3d/fig2_4.py                          |   2 +-
 figures/3d/fig3_1a.py                         |   2 +-
 figures/3d/fig3_1b.py                         |   2 +-
 figures/3d/fig7_13a.py                        |   2 +-
 figures/3d/fig7_4a.py                         |   2 +-
 figures/3d/fig7_4b.py                         |   2 +-
 figures/3d/fig7_4c.py                         |   2 +-
 figures/3d/fig7_7.py                          |   2 +-
 figures/3d/fig8_8a.py                         |   4 +-
 figures/3d/fig8_8b.py                         |   4 +-
 figures/3d/fig9_17.py                         |   4 +-
 figures/code/chapter2/fig2_14.py              |   8 +-
 figures/code/chapter2/fig2_15.py              |   6 +-
 figures/code/chapter2/fig2_16.py              |   6 +-
 figures/code/chapter2/fig2_4.py               |   2 +-
 figures/code/chapter2/fig2_6/aruco_markers.py |   2 +-
 .../chapter2/fig2_6/aruco_markers_pyvista.py  |   2 +-
 figures/code/chapter2/fig2_6/fig2_6.py        |   2 +-
 figures/code/chapter2/screw.py                |   2 +-
 figures/code/chapter2/vtkbug2.py              |   2 +-
 figures/code/chapter3/fig3_1a.py              |   2 +-
 figures/code/chapter3/fig3_1b.py              |   2 +-
 figures/code/chapter3/fig3_1c.py              |   2 +-
 figures/code/chapter7/fig7_10b.py             |   2 +-
 figures/code/chapter7/fig7_13a.py             |   2 +-
 figures/code/chapter7/fig7_4a.py              |   2 +-
 figures/code/chapter7/fig7_4b.py              |   2 +-
 figures/code/chapter7/fig7_4c.py              |   2 +-
 figures/code/chapter7/fig7_6.py               |   2 +-
 figures/code/chapter7/fig7_7.py               |   2 +-
 figures/code/chapter7/pyvista/extrude.py      |   2 +-
 figures/code/chapter7/pyvista/fig7_2a.py      |   2 +-
 figures/code/chapter7/pyvista/fig7_2b.py      |   2 +-
 figures/code/chapter7/pyvista/fig7_2c.py      |   2 +-
 figures/code/chapter7/pyvista/fig7_7b.py      |   2 +-
 figures/code/chapter8/fig8_8a.py              |   4 +-
 figures/code/chapter8/fig8_8b.py              |   4 +-
 figures/code/chapter9/fig9_17.py              |   6 +-
 pyproject.toml                                |   1 +
 42 files changed, 498 insertions(+), 56 deletions(-)
 create mode 100644 RVC3/tools/pvplus.py

diff --git a/RVC3/tools/pvplus.py b/RVC3/tools/pvplus.py
new file mode 100644
index 0000000..72d3c36
--- /dev/null
+++ b/RVC3/tools/pvplus.py
@@ -0,0 +1,441 @@
+# pvplus - PyVista extras for drawing coordinate frames, axes and ellipsoids
+
+import pyvista as pv
+import numpy as np
+from spatialmath import base
+from math import cos, sin, pi
+import vtk
+from spatialmath import SE3
+import os.path
+import sys
+from pathlib import Path
+from PIL import Image
+"""
+
+HINTS
+
+not very good at display coordinate frames/axes
+
+plotter.show_axes()  put a small frame for orientation in bottom left
+plotter.show_bounds(grid='front')  overlay a grid
+
+pv.save("mesh.vtk")
+pv.save_meshio("mesh.obj", mesh)
+
+plotter.export_obj(filename)
+plotter.export_vtkjs(filename)
+
+"""
+s=0.8
+sp=10
+ss = False
+se = False
+th = 0.3
+r = 100
+zl = -0.4
+
+
+def string(text, subscript=None, scale=1):
+
+    if '_' in text:
+        z = text.split('_')
+        text = z[0]
+        subscript = z[1]
+
+    # create the axis name
+    textmesh = pv.Text3D(text, depth=th)
+
+    # add the subscript
+    if subscript is not None:
+        submesh = pv.Text3D(subscript, depth=th)
+        submesh.points /= 1.5  # smaller
+
+        # shift it to the right and down a bit
+        m = np.max(textmesh.points, axis=0)
+
+
+        submesh.translate([m[0] * 0.9, -m[1] * 0.5, 0])
+        textmesh = textmesh + submesh  # append it
+
+    # centre the whole thing
+    textmesh.points -= np.mean(textmesh.points, axis=0)
+
+    # scale the text
+    textmesh.points *= scale / 5
+    return textmesh
+
+def add_arrow(p, T, i, color='silver', label=None, subscript=None, scale=1.0, opacity=1.0):
+
+    pos = [0, 0, 0]
+    pos[i] = 1.1 * scale
+
+    ## create the arrow to scale
+    arrow = pv.Arrow(direction=pos, tip_resolution=r, shaft_resolution=r)
+    arrow.points *= scale
+
+    arrow.transform(T, inplace=True)
+    p.add_mesh(arrow, color=color, specular=s, specular_power=sp, \
+        smooth_shading=ss, show_edges=se, opacity=opacity)
+
+    names = 'XYZ'
+
+    ## create the axis label text to scale
+
+    # create the axis name
+    text = pv.Text3D(names[i], depth=th)
+
+    # add the subscript
+    if label is not None:
+        axlabel = pv.Text3D(label, depth=th)
+        axlabel.points /= 1.5  # smaller
+
+        # shift it to the right and down a bit
+        m = np.max(text.points, axis=0)
+        axlabel.translate([m[0] * 0.8, -m[1] * 0.5, 0])
+        text = text + axlabel  # append it
+
+    # centre the whole thing
+    text.points -= np.mean(text.points, axis=0)
+
+    # scale the text
+    text.points *= scale / 5
+
+    # now orient it in space, rotate about centre
+    if i == 0:
+        text.rotate_x(90)
+    elif i == 1:
+        text.rotate_y(90)
+        text.rotate_x(90)
+    elif i == 2:
+        text.rotate_x(90)
+        text.rotate_z(90)
+
+    text.translate(pos)
+    text.transform(T, inplace=True)
+
+    ## combine arrow and text
+    p.add_mesh(text, color=color, opacity=opacity)
+    return arrow + text
+
+def add_frame(plotter, T=None, color=None, **kwargs):
+
+    if color is None:
+        colors = ['red', 'green', 'blue']
+    else:
+        colors = (color,) * 3
+
+    if T is None:
+        T = SE3()
+
+    T = T.A
+    add_arrow(plotter, T, 0, color=colors[0], **kwargs)
+    add_arrow(plotter, T, 1, color=colors[1], **kwargs)
+    add_arrow(plotter, T, 2, color=colors[2], **kwargs)
+
+def add_frame2(plotter, T, color=None, **kwargs):
+
+    if color is None:
+        colors = ['red', 'green']
+    else:
+        colors = (color,) * 2
+
+    T = T.A
+    add_arrow(plotter, T, 0, color=colors[0], **kwargs)
+    add_arrow(plotter, T, 1, color=colors[1], **kwargs)
+
+
+
+def ribbon(
+        length=0.75,
+        head=0.15,
+        r=0.2,
+        w=[0.2, 0.3],
+        N=100,
+        reverse=False,
+        phase=0,
+        T=None,
+    ):
+
+    length *= 2 * pi
+    head *= 2 * pi
+    phase *= 2 * pi
+    delta = length / N
+    Nh = int(head / delta)
+    Nt = int(length / delta) - Nh
+
+    if reverse:
+        delta = -delta
+
+    w1 = w[0] / 2
+    w2 = w[1] / 2
+
+    vertices = np.array([r * cos(phase), r * sin(phase), 0])
+    faces = np.array([
+        [3, 0, 1, 2],
+        [3, 0, 2, 3]
+        ])
+    # arrow
+    #   3 * Nh + 1 vertices
+    #   4 (Nh - 1) + 2 faces
+    for i in range(1, Nh):
+        w = w2 * (i + 1) / Nh
+        theta = phase  +(i + 1) * delta
+
+        x = r * cos(theta)
+        y = r * sin (theta)
+        vertices = np.vstack([
+            vertices,
+            [x, y, w],
+            [x, y, 0],
+            [x, y, -w]])
+
+        k = 3 * (i - 1)
+
+        if i < (Nh - 1):
+            faces = np.vstack([
+                faces,
+                [3, 1 + k, 4 + k, 5 + k],
+                [3, 1 + k, 5 + k, 2 + k],
+                [3, 3 + k, 2 + k, 5 + k],
+                [3, 3 + k, 5 + k, 6 + k]])
+
+        theta_h = theta
+        nv_h = vertices.shape[0]
+
+    # tail
+
+    for i in range(0, Nt):
+        theta = theta_h + i * delta
+
+        x = r * cos(theta)
+        y = r * sin (theta)
+        vertices = np.vstack([
+            vertices,
+            [x, y, w1],
+            [x, y, 0],
+            [x, y, -w1]])
+
+        k = nv_h + 3 * i - 1
+
+        if i < (Nt - 1):
+            faces = np.vstack([
+                faces,
+                [3, 1 + k, 4 + k, 2 + k],
+                [3, 2 + k, 4 + k, 5 + k],
+                [3, 2 + k, 5 + k, 6 + k],
+                [3, 2 + k, 6 + k, 3 + k]])
+
+
+    shape = pv.PolyData(vertices, faces)
+    if T is not None:
+        shape.transform(T.A, inplace=True)
+    return shape
+
+def axis(plotter, T=None, text=None, direction=(0,0,1), square=False, twist=0.5):
+
+    if square:
+        arrow = pv.Arrow(direction=direction, tip_resolution=4, \
+            shaft_resolution=4, shaft_radius=0.03,
+            tip_radius=0.08, tip_length=0.2)
+    else:
+        arrow = pv.Arrow(direction=(0,0,1), tip_resolution=r, \
+            shaft_resolution=r, shaft_radius=0.03,
+            tip_radius=0.08, tip_length=0.2)
+
+    if T is None:
+        T = SE3()
+    T = SE3(T.t)  # remove rotation
+    Ta = T * SE3(0, 0, zl)
+    Tr = T * SE3(0, 0, 0.2)
+    arrow.transform(Ta.A, inplace=True)
+    rib = ribbon(reverse=True, r=0.1, w=[0.12, 0.2], phase=0.08)
+    rib.transform(Tr.A, inplace=True)
+    plotter.add_mesh(arrow)
+    plotter.add_mesh(rib, color='#808080')
+
+    if text is not None:
+        t = string(text, scale=0.5)
+        t.transform((T  * SE3(0, 0, zl) * SE3(np.r_[direction] * 1.1) * SE3.Rz(twist) * SE3.Rx(pi/2) ).A, inplace=True)
+        plotter.add_mesh(t)
+
+def add_ellipsoid(plotter, A, inverted=False, **kwargs):
+
+    if not inverted:
+        A = np.linalg.inv(A)
+
+    # compute eigenvalues and vectors
+    e, x = np.linalg.eig(A)
+
+    # the radii are square root of the eigenvalues
+    radii = np.sqrt(e)
+    ellipsoid = pv.ParametricEllipsoid(xradius=radii[0], yradius=radii[1], zradius=radii[2])
+
+    # now orient it
+    R = np.real(x)
+    T = base.r2t(R)
+    ellipsoid.transform(T, inplace=True)
+
+    plotter.add_mesh(ellipsoid, **kwargs)
+
+    return ellipsoid
+
+def ellipsoid_3d(plotter, A, **kwargs):
+
+    plotter.disable_parallel_projection()
+
+    colors = vtk.vtkNamedColors()
+
+    plotter.renderer.RemoveAllLights()
+
+    # top light, XY plane
+    light1 = vtk.vtkLight()
+    light1.SetFocalPoint(0, 0, 0)
+    light1.SetPosition(0, 0, 2)
+    light1.SetColor(colors.GetColor3d('white'))
+    light1.SetIntensity(1)
+    plotter.renderer.AddLight(light1)
+
+    # X direction light, YZ plane
+    light2 = vtk.vtkLight()
+    light2.SetFocalPoint(0, 0, 0)
+    light2.SetPosition(2, 0, 0)
+    light2.SetColor(colors.GetColor3d('white'))
+    light2.SetIntensity(1)
+    plotter.renderer.AddLight(light2)
+
+    # Y direction light, XZ plane
+    light3 = vtk.vtkLight()
+    light3.SetFocalPoint(0, 0, 0)
+    light3.SetPosition(0, 2, 0)
+    light3.SetColor(colors.GetColor3d('white'))
+    light3.SetIntensity(1)
+    plotter.renderer.AddLight(light3)
+
+    # Add 3 backing planes
+    D = 5
+    z0 = -D / 2
+    T = 0.02
+    plane_mesh1 = pv.Cube([0, 0, z0], D, D, T)
+    plane_mesh2 = pv.Cube([-D/2, 0, D/2 + z0], T, D, D)
+    plane_mesh3 = pv.Cube([0, -D/2, D/2 + z0], D, T, D)
+    # add the meshes to scene
+    plotter.add_mesh(plane_mesh1 + plane_mesh2 + plane_mesh3,
+        show_edges=True, ambient=0.3, diffuse=0.8, specular=0.8, specular_power=30, smooth_shading=True)
+
+    # do the ellipsoid
+    e = add_ellipsoid(plotter, A, ambient=0.5, diffuse=0.5, specular=0.8, specular_power=30,
+                smooth_shading=True, color='dodgerblue', **kwargs)
+
+    # do the shadows
+    plotter.renderer.SetUseShadows(True)
+
+if __name__ == "__main__":
+
+    from spatialmath import SE3
+
+    plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
+
+    # add_frame(plotter, SE3())
+
+    # data from RVC2 fig 8.4b
+    # A = np.array([
+    # 		[ 0.0076,    0.0000,   -0.0868],
+    # 		[ 0.0000,    3.0000,   -0.0000],
+    # 		[-0.0868,   -0.0000,    2.9924]
+    # 	])
+    # e = add_ellipsoid(plotter, A, inverted=True, color='skyblue', style='wireframe')
+    # e.plot(show_grid=True)
+
+    add_frame(plotter, SE3())
+
+    plotter.set_background('white')
+    plotter.enable_parallel_projection()
+    # plotter.show_axes()
+    # plotter.show_bounds(grid='front')
+    plotter.show()
+
+def outfile(format='png'):
+    # build the path for saving, next to the calling script (whatever
+    # figures/... directory it happens to live in), not a hardcoded
+    # personal path
+    script_dir = Path(sys.argv[0]).resolve().parent
+    figure = os.path.basename(sys.argv[0])
+    figure = os.path.splitext(figure)[0] + '.' + format
+    return str(script_dir / figure)
+
+
+
+def zoomplot(plotter, value):
+    if not plotter.camera_set:
+        plotter.camera_position = plotter.get_default_cam_pos()
+        plotter.reset_camera()
+        plotter.camera_set = True
+    plotter.camera.Zoom(value)
+    plotter.render()
+
+margin = 5
+
+def cropimage(im):
+
+    bg = []
+
+    def limits(a):
+        s = a.index(False) - margin
+        if s < 0:
+            s = 0
+
+        a.reverse()
+        e = a.index(False) - margin
+        if e < 0:
+            e = 0
+        e = len(a) - e
+
+        return s, e
+
+    for c in range(im.shape[1]):
+        column = im[:,c,:3]
+        t = np.all(column == (255, 255, 255))
+        bg.append(t)
+
+    c1, c2 = limits(bg)
+
+    bg = []
+    for r in range(im.shape[0]):
+        row = im[r,:,:3]
+        t = np.all(row == (255, 255, 255))
+        bg.append(t)
+
+    r1, r2 = limits(bg)
+
+    print(f"image: rows {r1}-{r2}, columns {c1}-{c2}")
+
+    return im[r1:r2, c1:c2, :]
+
+
+def save(plotter, show=True, zoom=None, crop=True):
+    # output file name
+    out = outfile()
+
+    # configure PyVista
+    plotter.set_background('white')
+
+    plotter.off_screen = not show
+
+    if zoom is not None:
+        zoomplot(plotter, zoom)
+
+    if show:
+        # plotter.save_graphic('ZZZ.png', raster=False)
+        plotter.show()
+    else:
+        im = plotter.screenshot()
+        print(im.shape)
+        if crop:
+            im = cropimage(im)
+
+        image = Image.fromarray(im)
+        image.save(out)
+
+        # plotter.save_graphic('fig7_2b.png', raster=False)
+
+        print('saving plotter --> ', out)
diff --git a/figures/3d/fig2_14.py b/figures/3d/fig2_14.py
index 84de552..b28e3de 100755
--- a/figures/3d/fig2_14.py
+++ b/figures/3d/fig2_14.py
@@ -3,8 +3,8 @@
 import numpy as np
 from spatialmath import SE3
 from math import cos, sin, pi
-import pvplus
-import rvcprint
+from RVC3.tools import pvplus
+# import rvcprint  -- book-production helper, not needed here
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000), off_screen=True)
diff --git a/figures/3d/fig2_16.py b/figures/3d/fig2_16.py
index 8419061..72d5019 100755
--- a/figures/3d/fig2_16.py
+++ b/figures/3d/fig2_16.py
@@ -3,8 +3,8 @@
 import numpy as np
 from spatialmath import SE3
 from math import pi
-import pvplus
-import rvcprint
+from RVC3.tools import pvplus
+# import rvcprint  -- book-production helper, not needed here
 
 plotter = pv.Plotter(border=False, polygon_smoothing=True, window_size=(2000,1000))
 plotter.set_background('white')
diff --git a/figures/3d/fig2_4.py b/figures/3d/fig2_4.py
index ae1c7df..b0ec7f0 100755
--- a/figures/3d/fig2_4.py
+++ b/figures/3d/fig2_4.py
@@ -4,7 +4,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 
diff --git a/figures/3d/fig3_1a.py b/figures/3d/fig3_1a.py
index 4ff19d0..430d249 100755
--- a/figures/3d/fig3_1a.py
+++ b/figures/3d/fig3_1a.py
@@ -5,7 +5,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 plotter.enable_parallel_projection()
diff --git a/figures/3d/fig3_1b.py b/figures/3d/fig3_1b.py
index bc80359..1570f81 100755
--- a/figures/3d/fig3_1b.py
+++ b/figures/3d/fig3_1b.py
@@ -4,7 +4,7 @@
 import numpy as np
 from spatialmath import SE3
 from math import cos, sin, pi
-import pvplus
+from RVC3.tools import pvplus
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
diff --git a/figures/3d/fig7_13a.py b/figures/3d/fig7_13a.py
index fd34c4f..99f49a8 100755
--- a/figures/3d/fig7_13a.py
+++ b/figures/3d/fig7_13a.py
@@ -3,7 +3,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 def zoom(plotter, value):
     if not plotter.camera_set:
diff --git a/figures/3d/fig7_4a.py b/figures/3d/fig7_4a.py
index 408a601..c7e87de 100755
--- a/figures/3d/fig7_4a.py
+++ b/figures/3d/fig7_4a.py
@@ -6,7 +6,7 @@
 from math import cos, sin, pi
 from roboticstoolbox import ETS2 as ET
 
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 overlap = 0.2
diff --git a/figures/3d/fig7_4b.py b/figures/3d/fig7_4b.py
index 6b5d116..7a7db8b 100755
--- a/figures/3d/fig7_4b.py
+++ b/figures/3d/fig7_4b.py
@@ -6,7 +6,7 @@
 from math import cos, sin, pi
 
 
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 overlap = 0.2
diff --git a/figures/3d/fig7_4c.py b/figures/3d/fig7_4c.py
index 94ff020..e660c53 100755
--- a/figures/3d/fig7_4c.py
+++ b/figures/3d/fig7_4c.py
@@ -5,7 +5,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 
 
diff --git a/figures/3d/fig7_7.py b/figures/3d/fig7_7.py
index 3bb901b..600dfcc 100755
--- a/figures/3d/fig7_7.py
+++ b/figures/3d/fig7_7.py
@@ -5,7 +5,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 def zoom(plotter, value):
     if not plotter.camera_set:
diff --git a/figures/3d/fig8_8a.py b/figures/3d/fig8_8a.py
index f95ee83..2710547 100755
--- a/figures/3d/fig8_8a.py
+++ b/figures/3d/fig8_8a.py
@@ -5,9 +5,9 @@
 # from spatialmath import SE3
 from spatialmath import base
 from math import cos, sin, pi
-import pvplus
+from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-from rvcprint import outfile
+# from rvcprint import outfile  -- book-production helper, not needed here
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 print(pv.__version__)
diff --git a/figures/3d/fig8_8b.py b/figures/3d/fig8_8b.py
index c353df4..cc7b531 100755
--- a/figures/3d/fig8_8b.py
+++ b/figures/3d/fig8_8b.py
@@ -6,9 +6,9 @@
 # from spatialmath import SE3
 from spatialmath import base
 from math import cos, sin, pi
-import pvplus
+from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-from rvcprint import outfile
+# from rvcprint import outfile  -- book-production helper, not needed here
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
diff --git a/figures/3d/fig9_17.py b/figures/3d/fig9_17.py
index 5847804..0826998 100755
--- a/figures/3d/fig9_17.py
+++ b/figures/3d/fig9_17.py
@@ -5,9 +5,9 @@
 # from spatialmath import SE3
 from spatialmath import base
 from math import cos, sin, pi
-import pvplus
+from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-from rvcprint import outfile
+# from rvcprint import outfile  -- book-production helper, not needed here
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 print(pv.__version__)
diff --git a/figures/code/chapter2/fig2_14.py b/figures/code/chapter2/fig2_14.py
index da9f2ab..d2a5698 100755
--- a/figures/code/chapter2/fig2_14.py
+++ b/figures/code/chapter2/fig2_14.py
@@ -3,8 +3,8 @@
 import numpy as np
 from spatialmath import SE3
 from math import cos, sin, pi
-import pvplus
-from RVC3.tools import rvcprint
+from RVC3.tools import pvplus
+# from RVC3.tools import rvcprint  -- book-production helper, not needed here
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000), off_screen=True)
@@ -18,6 +18,6 @@
 plotter.set_background('white')
 # plotter.enable_eye_dome_lighting()  # messes up subplots
 
-filename = rvcprint.outfile(format='png', include=True)
+# filename = rvcprint.outfile(format='png', include=True)  -- book-production helper, not needed here
 
-plotter.show(screenshot=filename)
+plotter.show()
diff --git a/figures/code/chapter2/fig2_15.py b/figures/code/chapter2/fig2_15.py
index 87dace2..5d330b1 100755
--- a/figures/code/chapter2/fig2_15.py
+++ b/figures/code/chapter2/fig2_15.py
@@ -2,8 +2,8 @@
 import pyvista as pv
 import numpy as np
 from spatialmath import SE3
-import pvplus
-from RVC3.tools import rvcprint
+from RVC3.tools import pvplus
+# from RVC3.tools import rvcprint  -- book-production helper, not needed here
 
 plotter = pv.Plotter(shape=(2,3), border=False, polygon_smoothing=True, window_size=(2000,1000))
 plotter.enable_parallel_projection()
@@ -25,4 +25,4 @@ def add_plot(i, j, T):
 plotter.set_background('white')
 # plotter.enable_eye_dome_lighting()  # messes up subplots
 
-plotter.show(screenshot=rvcprint.outfile(format='png'))
\ No newline at end of file
+plotter.show()
\ No newline at end of file
diff --git a/figures/code/chapter2/fig2_16.py b/figures/code/chapter2/fig2_16.py
index b122de7..c696e52 100755
--- a/figures/code/chapter2/fig2_16.py
+++ b/figures/code/chapter2/fig2_16.py
@@ -3,8 +3,8 @@
 import numpy as np
 from spatialmath import SE3
 from math import pi
-import pvplus
-from RVC3.tools import rvcprint
+from RVC3.tools import pvplus
+# from RVC3.tools import rvcprint  -- book-production helper, not needed here
 
 plotter = pv.Plotter(shape=(2,3), border=False, polygon_smoothing=True, window_size=(2000,1000))
 plotter.set_background('white')
@@ -60,4 +60,4 @@ def add_plot(i, j, T):
 
 # plotter.enable_eye_dome_lighting()  # messes up subplots
 
-plotter.show(screenshot=rvcprint.outfile(format='png'))
\ No newline at end of file
+plotter.show()
\ No newline at end of file
diff --git a/figures/code/chapter2/fig2_4.py b/figures/code/chapter2/fig2_4.py
index 1d23572..97f58c8 100755
--- a/figures/code/chapter2/fig2_4.py
+++ b/figures/code/chapter2/fig2_4.py
@@ -4,7 +4,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 
diff --git a/figures/code/chapter2/fig2_6/aruco_markers.py b/figures/code/chapter2/fig2_6/aruco_markers.py
index 74b8287..f3ff407 100644
--- a/figures/code/chapter2/fig2_6/aruco_markers.py
+++ b/figures/code/chapter2/fig2_6/aruco_markers.py
@@ -4,7 +4,7 @@
 import cv2.aruco as aruco
 from spatialmath import SE3, SO3
 import pyvista as pv
-import pvplus
+from RVC3.tools import pvplus
 
 
 def main():
diff --git a/figures/code/chapter2/fig2_6/aruco_markers_pyvista.py b/figures/code/chapter2/fig2_6/aruco_markers_pyvista.py
index eb79e2e..cb15e47 100644
--- a/figures/code/chapter2/fig2_6/aruco_markers_pyvista.py
+++ b/figures/code/chapter2/fig2_6/aruco_markers_pyvista.py
@@ -4,7 +4,7 @@
 import cv2.aruco as aruco
 from spatialmath import SE3
 import pyvista as pv
-import pvplus
+from RVC3.tools import pvplus
 
 
 def main():
diff --git a/figures/code/chapter2/fig2_6/fig2_6.py b/figures/code/chapter2/fig2_6/fig2_6.py
index 8c250a0..ee154d7 100755
--- a/figures/code/chapter2/fig2_6/fig2_6.py
+++ b/figures/code/chapter2/fig2_6/fig2_6.py
@@ -4,7 +4,7 @@
 import matplotlib.pyplot as plt
 import pyvista as pv
 import vtk
-import pvplus
+from RVC3.tools import pvplus
 
 scene = Image('IMG_8787.JPG')
 
diff --git a/figures/code/chapter2/screw.py b/figures/code/chapter2/screw.py
index 9dc7e8b..1dc67fb 100755
--- a/figures/code/chapter2/screw.py
+++ b/figures/code/chapter2/screw.py
@@ -2,7 +2,7 @@
 import pyvista as pv
 import numpy as np
 from spatialmath import SE3
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(shape=(2,3), border=False, polygon_smoothing=True, window_size=(2000,1000))
 plotter.enable_parallel_projection()
diff --git a/figures/code/chapter2/vtkbug2.py b/figures/code/chapter2/vtkbug2.py
index 707f351..3068a91 100755
--- a/figures/code/chapter2/vtkbug2.py
+++ b/figures/code/chapter2/vtkbug2.py
@@ -2,7 +2,7 @@
 import matplotlib.pyplot as plt
 import pyvista as pv
 import vtk
-import pvplus
+from RVC3.tools import pvplus
 from spatialmath import SE3
 import numpy as np
 
diff --git a/figures/code/chapter3/fig3_1a.py b/figures/code/chapter3/fig3_1a.py
index 00167de..ecafe10 100755
--- a/figures/code/chapter3/fig3_1a.py
+++ b/figures/code/chapter3/fig3_1a.py
@@ -5,7 +5,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 plotter.enable_parallel_projection()
diff --git a/figures/code/chapter3/fig3_1b.py b/figures/code/chapter3/fig3_1b.py
index fb29faa..51b4467 100755
--- a/figures/code/chapter3/fig3_1b.py
+++ b/figures/code/chapter3/fig3_1b.py
@@ -4,7 +4,7 @@
 import numpy as np
 from spatialmath import SE3
 from math import cos, sin, pi
-import pvplus
+from RVC3.tools import pvplus
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
diff --git a/figures/code/chapter3/fig3_1c.py b/figures/code/chapter3/fig3_1c.py
index 1aa0a93..8c3c6b8 100755
--- a/figures/code/chapter3/fig3_1c.py
+++ b/figures/code/chapter3/fig3_1c.py
@@ -4,7 +4,7 @@
 import numpy as np
 from spatialmath import SE3
 from math import cos, sin, pi
-import pvplus
+from RVC3.tools import pvplus
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
diff --git a/figures/code/chapter7/fig7_10b.py b/figures/code/chapter7/fig7_10b.py
index 58ae108..3175387 100755
--- a/figures/code/chapter7/fig7_10b.py
+++ b/figures/code/chapter7/fig7_10b.py
@@ -2,7 +2,7 @@
 
 from roboticstoolbox import *
 import pyvista as pv
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 
diff --git a/figures/code/chapter7/fig7_13a.py b/figures/code/chapter7/fig7_13a.py
index cef7d57..5fe0916 100755
--- a/figures/code/chapter7/fig7_13a.py
+++ b/figures/code/chapter7/fig7_13a.py
@@ -3,7 +3,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 def zoom(plotter, value):
     if not plotter.camera_set:
diff --git a/figures/code/chapter7/fig7_4a.py b/figures/code/chapter7/fig7_4a.py
index 91cf86c..bd67050 100755
--- a/figures/code/chapter7/fig7_4a.py
+++ b/figures/code/chapter7/fig7_4a.py
@@ -6,7 +6,7 @@
 from math import cos, sin, pi
 from roboticstoolbox import ETS2 as ET
 
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 overlap = 0.2
diff --git a/figures/code/chapter7/fig7_4b.py b/figures/code/chapter7/fig7_4b.py
index 130a585..1eb5c19 100755
--- a/figures/code/chapter7/fig7_4b.py
+++ b/figures/code/chapter7/fig7_4b.py
@@ -6,7 +6,7 @@
 from math import cos, sin, pi
 
 
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 overlap = 0.2
diff --git a/figures/code/chapter7/fig7_4c.py b/figures/code/chapter7/fig7_4c.py
index 91eac4d..3b28c8c 100755
--- a/figures/code/chapter7/fig7_4c.py
+++ b/figures/code/chapter7/fig7_4c.py
@@ -5,7 +5,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 
 
diff --git a/figures/code/chapter7/fig7_6.py b/figures/code/chapter7/fig7_6.py
index 1ed4acd..7297d41 100755
--- a/figures/code/chapter7/fig7_6.py
+++ b/figures/code/chapter7/fig7_6.py
@@ -5,7 +5,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 def zoom(plotter, value):
     if not plotter.camera_set:
diff --git a/figures/code/chapter7/fig7_7.py b/figures/code/chapter7/fig7_7.py
index d001f93..32ebe1a 100755
--- a/figures/code/chapter7/fig7_7.py
+++ b/figures/code/chapter7/fig7_7.py
@@ -5,7 +5,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 def zoom(plotter, value):
     if not plotter.camera_set:
diff --git a/figures/code/chapter7/pyvista/extrude.py b/figures/code/chapter7/pyvista/extrude.py
index cef7d57..5fe0916 100644
--- a/figures/code/chapter7/pyvista/extrude.py
+++ b/figures/code/chapter7/pyvista/extrude.py
@@ -3,7 +3,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 def zoom(plotter, value):
     if not plotter.camera_set:
diff --git a/figures/code/chapter7/pyvista/fig7_2a.py b/figures/code/chapter7/pyvista/fig7_2a.py
index 8bc6615..6a30b69 100755
--- a/figures/code/chapter7/pyvista/fig7_2a.py
+++ b/figures/code/chapter7/pyvista/fig7_2a.py
@@ -5,7 +5,7 @@
 from roboticstoolbox import ETS2 as ET
 
 
-import pvplus
+from RVC3.tools import pvplus
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
diff --git a/figures/code/chapter7/pyvista/fig7_2b.py b/figures/code/chapter7/pyvista/fig7_2b.py
index 1be3f73..4ce046b 100755
--- a/figures/code/chapter7/pyvista/fig7_2b.py
+++ b/figures/code/chapter7/pyvista/fig7_2b.py
@@ -4,7 +4,7 @@
 from math import cos, sin, pi
 
 
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 overlap = 0.2
diff --git a/figures/code/chapter7/pyvista/fig7_2c.py b/figures/code/chapter7/pyvista/fig7_2c.py
index 0fc1d0f..eb71cf9 100755
--- a/figures/code/chapter7/pyvista/fig7_2c.py
+++ b/figures/code/chapter7/pyvista/fig7_2c.py
@@ -3,7 +3,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 
-import pvplus
+from RVC3.tools import pvplus
 
 
 
diff --git a/figures/code/chapter7/pyvista/fig7_7b.py b/figures/code/chapter7/pyvista/fig7_7b.py
index 9bc6a23..53f67e4 100755
--- a/figures/code/chapter7/pyvista/fig7_7b.py
+++ b/figures/code/chapter7/pyvista/fig7_7b.py
@@ -1,6 +1,6 @@
 from roboticstoolbox import *
 import pyvista as pv
-import pvplus
+from RVC3.tools import pvplus
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 
diff --git a/figures/code/chapter8/fig8_8a.py b/figures/code/chapter8/fig8_8a.py
index 51d710e..d17db60 100755
--- a/figures/code/chapter8/fig8_8a.py
+++ b/figures/code/chapter8/fig8_8a.py
@@ -5,9 +5,9 @@
 # from spatialmath import SE3
 from spatialmath import base
 from math import cos, sin, pi
-import pvplus
+from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-from rvcprint import outfile
+# from rvcprint import outfile  -- book-production helper, not needed here
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 print(pv.__version__)
diff --git a/figures/code/chapter8/fig8_8b.py b/figures/code/chapter8/fig8_8b.py
index 0cd7aae..e5e4ef8 100755
--- a/figures/code/chapter8/fig8_8b.py
+++ b/figures/code/chapter8/fig8_8b.py
@@ -6,9 +6,9 @@
 # from spatialmath import SE3
 from spatialmath import base
 from math import cos, sin, pi
-import pvplus
+from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-from rvcprint import outfile
+# from rvcprint import outfile  -- book-production helper, not needed here
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
diff --git a/figures/code/chapter9/fig9_17.py b/figures/code/chapter9/fig9_17.py
index 0755216..17e1a71 100755
--- a/figures/code/chapter9/fig9_17.py
+++ b/figures/code/chapter9/fig9_17.py
@@ -5,9 +5,9 @@
 # from spatialmath import SE3
 from spatialmath import base
 from math import cos, sin, pi
-import pvplus
+from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-from rvcprint import outfile
+# from rvcprint import outfile  -- book-production helper, not needed here
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 print(pv.__version__)
@@ -43,4 +43,4 @@
 
 # plotter.add_axes()
 # plotter.export_obj('exported.obj')
-plotter.show(screenshot=outfile(format='png'))
+plotter.show()
diff --git a/pyproject.toml b/pyproject.toml
index eab80eb..12c4649 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -97,6 +97,7 @@ dependencies = [
 
 pytorch = ["torch", "torchvision"]
 dev = ["pre-commit", "nbstripout"]
+figures = ["pyvista", "vtk", "pillow"]
 
 [project.scripts]
 

From f252b44e1c14b75f55fdb91ab79579283450a85f Mon Sep 17 00:00:00 2001
From: Peter Corke <peter.i.corke@gmail.com>
Date: Mon, 17 Aug 2026 14:53:07 +1000
Subject: [PATCH 2/3] fix: scope rvcprint cleanup to figures/3d/ only, remove
 where unused

Correction to the previous commit, which touched rvcprint in some
figures/code/chapterN/ scripts too. figures/code/README.md documents
that rvcprint is the required, intentional mechanism those scripts use
to save the book's PDF figures -- it was never broken there and
shouldn't have been touched. Reverted those 6 files back to their
original state (only the pvplus import fix remains).

For the 6 figures/3d/*.py scripts that reference rvcprint (the tree
issue #20 is actually about): none of them use it for their real
output mechanism (they all call plotter.export_gltf(...) directly,
confirmed by figures/3d/README.md), so removed the now-fully-unused
import from each rather than leaving a disabled trace of it.
---
 figures/3d/fig2_14.py            | 1 -
 figures/3d/fig2_16.py            | 1 -
 figures/3d/fig2_24.py            | 1 -
 figures/3d/fig8_8a.py            | 1 -
 figures/3d/fig8_8b.py            | 1 -
 figures/3d/fig9_17.py            | 1 -
 figures/code/chapter2/fig2_14.py | 6 +++---
 figures/code/chapter2/fig2_15.py | 4 ++--
 figures/code/chapter2/fig2_16.py | 4 ++--
 figures/code/chapter8/fig8_8a.py | 2 +-
 figures/code/chapter8/fig8_8b.py | 2 +-
 figures/code/chapter9/fig9_17.py | 4 ++--
 12 files changed, 11 insertions(+), 17 deletions(-)

diff --git a/figures/3d/fig2_14.py b/figures/3d/fig2_14.py
index b28e3de..4769bdf 100755
--- a/figures/3d/fig2_14.py
+++ b/figures/3d/fig2_14.py
@@ -4,7 +4,6 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 from RVC3.tools import pvplus
-# import rvcprint  -- book-production helper, not needed here
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000), off_screen=True)
diff --git a/figures/3d/fig2_16.py b/figures/3d/fig2_16.py
index 72d5019..ecc0cd0 100755
--- a/figures/3d/fig2_16.py
+++ b/figures/3d/fig2_16.py
@@ -4,7 +4,6 @@
 from spatialmath import SE3
 from math import pi
 from RVC3.tools import pvplus
-# import rvcprint  -- book-production helper, not needed here
 
 plotter = pv.Plotter(border=False, polygon_smoothing=True, window_size=(2000,1000))
 plotter.set_background('white')
diff --git a/figures/3d/fig2_24.py b/figures/3d/fig2_24.py
index ed5165b..c4d0455 100755
--- a/figures/3d/fig2_24.py
+++ b/figures/3d/fig2_24.py
@@ -4,7 +4,6 @@
 from spatialmath import SE3, Twist3
 from spatialmath import base
 from math import cos, sin, pi
-import rvcprint
 from PIL import Image
 
 def add_arrow(i, T):
diff --git a/figures/3d/fig8_8a.py b/figures/3d/fig8_8a.py
index 2710547..6a43e54 100755
--- a/figures/3d/fig8_8a.py
+++ b/figures/3d/fig8_8a.py
@@ -7,7 +7,6 @@
 from math import cos, sin, pi
 from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-# from rvcprint import outfile  -- book-production helper, not needed here
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 print(pv.__version__)
diff --git a/figures/3d/fig8_8b.py b/figures/3d/fig8_8b.py
index cc7b531..d6fa93d 100755
--- a/figures/3d/fig8_8b.py
+++ b/figures/3d/fig8_8b.py
@@ -8,7 +8,6 @@
 from math import cos, sin, pi
 from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-# from rvcprint import outfile  -- book-production helper, not needed here
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
diff --git a/figures/3d/fig9_17.py b/figures/3d/fig9_17.py
index 0826998..eaf5556 100755
--- a/figures/3d/fig9_17.py
+++ b/figures/3d/fig9_17.py
@@ -7,7 +7,6 @@
 from math import cos, sin, pi
 from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-# from rvcprint import outfile  -- book-production helper, not needed here
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 print(pv.__version__)
diff --git a/figures/code/chapter2/fig2_14.py b/figures/code/chapter2/fig2_14.py
index d2a5698..d651ade 100755
--- a/figures/code/chapter2/fig2_14.py
+++ b/figures/code/chapter2/fig2_14.py
@@ -4,7 +4,7 @@
 from spatialmath import SE3
 from math import cos, sin, pi
 from RVC3.tools import pvplus
-# from RVC3.tools import rvcprint  -- book-production helper, not needed here
+from RVC3.tools import rvcprint
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000), off_screen=True)
@@ -18,6 +18,6 @@
 plotter.set_background('white')
 # plotter.enable_eye_dome_lighting()  # messes up subplots
 
-# filename = rvcprint.outfile(format='png', include=True)  -- book-production helper, not needed here
+filename = rvcprint.outfile(format='png', include=True)
 
-plotter.show()
+plotter.show(screenshot=filename)
diff --git a/figures/code/chapter2/fig2_15.py b/figures/code/chapter2/fig2_15.py
index 5d330b1..96575ba 100755
--- a/figures/code/chapter2/fig2_15.py
+++ b/figures/code/chapter2/fig2_15.py
@@ -3,7 +3,7 @@
 import numpy as np
 from spatialmath import SE3
 from RVC3.tools import pvplus
-# from RVC3.tools import rvcprint  -- book-production helper, not needed here
+from RVC3.tools import rvcprint
 
 plotter = pv.Plotter(shape=(2,3), border=False, polygon_smoothing=True, window_size=(2000,1000))
 plotter.enable_parallel_projection()
@@ -25,4 +25,4 @@ def add_plot(i, j, T):
 plotter.set_background('white')
 # plotter.enable_eye_dome_lighting()  # messes up subplots
 
-plotter.show()
\ No newline at end of file
+plotter.show(screenshot=rvcprint.outfile(format='png'))
\ No newline at end of file
diff --git a/figures/code/chapter2/fig2_16.py b/figures/code/chapter2/fig2_16.py
index c696e52..ea315be 100755
--- a/figures/code/chapter2/fig2_16.py
+++ b/figures/code/chapter2/fig2_16.py
@@ -4,7 +4,7 @@
 from spatialmath import SE3
 from math import pi
 from RVC3.tools import pvplus
-# from RVC3.tools import rvcprint  -- book-production helper, not needed here
+from RVC3.tools import rvcprint
 
 plotter = pv.Plotter(shape=(2,3), border=False, polygon_smoothing=True, window_size=(2000,1000))
 plotter.set_background('white')
@@ -60,4 +60,4 @@ def add_plot(i, j, T):
 
 # plotter.enable_eye_dome_lighting()  # messes up subplots
 
-plotter.show()
\ No newline at end of file
+plotter.show(screenshot=rvcprint.outfile(format='png'))
\ No newline at end of file
diff --git a/figures/code/chapter8/fig8_8a.py b/figures/code/chapter8/fig8_8a.py
index d17db60..482711c 100755
--- a/figures/code/chapter8/fig8_8a.py
+++ b/figures/code/chapter8/fig8_8a.py
@@ -7,7 +7,7 @@
 from math import cos, sin, pi
 from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-# from rvcprint import outfile  -- book-production helper, not needed here
+from rvcprint import outfile
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 print(pv.__version__)
diff --git a/figures/code/chapter8/fig8_8b.py b/figures/code/chapter8/fig8_8b.py
index e5e4ef8..cbb7f38 100755
--- a/figures/code/chapter8/fig8_8b.py
+++ b/figures/code/chapter8/fig8_8b.py
@@ -8,7 +8,7 @@
 from math import cos, sin, pi
 from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-# from rvcprint import outfile  -- book-production helper, not needed here
+from rvcprint import outfile
 
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
diff --git a/figures/code/chapter9/fig9_17.py b/figures/code/chapter9/fig9_17.py
index 17e1a71..a2d5a35 100755
--- a/figures/code/chapter9/fig9_17.py
+++ b/figures/code/chapter9/fig9_17.py
@@ -7,7 +7,7 @@
 from math import cos, sin, pi
 from RVC3.tools import pvplus
 import roboticstoolbox as rtb
-# from rvcprint import outfile  -- book-production helper, not needed here
+from rvcprint import outfile
 
 plotter = pv.Plotter(polygon_smoothing=True, window_size=(2000,2000))
 print(pv.__version__)
@@ -43,4 +43,4 @@
 
 # plotter.add_axes()
 # plotter.export_obj('exported.obj')
-plotter.show()
+plotter.show(screenshot=outfile(format='png'))

From c57f4591ee2be355940629764bb65f16b3d6613d Mon Sep 17 00:00:00 2001
From: Peter Corke <peter.i.corke@gmail.com>
Date: Mon, 17 Aug 2026 14:55:28 +1000
Subject: [PATCH 3/3] docs: fix package name typo in figures/code/README.md

rvcpython -> rvc3python (doesn't exist on PyPI; rvc3python does, and
matches pyproject.toml's declared name).
---
 figures/code/README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/figures/code/README.md b/figures/code/README.md
index 839f5f9..caeb3bc 100644
--- a/figures/code/README.md
+++ b/figures/code/README.md
@@ -35,7 +35,7 @@ saving -->  fig10_20.pdf
 Some files generate multiple sub-figures with lowercase letter suffixes.
 
 All these files use `RVC3.tools.rvcprint` to save the created files.  The
-package `rvcpython` must have been installed. 
+package `rvc3python` must have been installed.