fixed arrow_3d incorrect behavior

spb/backends/matplotlib/renderers/arrow2d.py

@@ -11,7 +11,7 @@ class Arrow2DRendererQuivers(MatplotlibRenderer):
 
 def _draw_arrow_2d(renderer, data):
     p, s = renderer.plot, renderer.series
-    xx, yy, uu, vv = data
+    x1, y1, x2, y2 = data
     mpatches = p.matplotlib.patches
 
     arrowstyle = mpatches.ArrowStyle(
@@ -23,7 +23,7 @@ def _draw_arrow_2d(renderer, data):
         color=next(p._cl)
     )
     kw = p.merge({}, pkw, s.rendering_kw)
-    arrow = mpatches.FancyArrowPatch((xx, yy), (uu, vv), **kw)
+    arrow = mpatches.FancyArrowPatch((x1, y1), (x2, y2), **kw)
     p._ax.add_patch(arrow)
 
     if s.show_in_legend:
@@ -36,9 +36,9 @@ def _draw_arrow_2d(renderer, data):
 
 
 def _update_arrow2d(renderer, data, handle):
-    xx, yy, uu, vv = data
+    x1, y1, x2, y2 = data
     arrow = handle[0]
-    arrow.set_positions((xx, yy), (uu, vv))
+    arrow.set_positions((x1, y1), (x2, y2))
 
 
 class Arrow2DRendererFancyArrowPatch(MatplotlibRenderer):

spb/backends/matplotlib/renderers/arrow3d.py

@@ -46,7 +46,8 @@ def do_3d_projection(self, renderer=None):
 
 def _draw_arrow_3d(renderer, data):
     p, s = renderer.plot, renderer.series
-    xx, yy, zz, uu, vv, ww = data
+    x1, y1, z1, x2, y2, z2 = data
+    dx, dy, dz = x2 - x1, y2 - y1, z2 - z1
     mpatches = p.matplotlib.patches
 
     arrowstyle = mpatches.ArrowStyle(
@@ -58,7 +59,7 @@ def _draw_arrow_3d(renderer, data):
         color=next(p._cl)
     )
     kw = p.merge({}, pkw, s.rendering_kw)
-    arrow = Arrow3D(xx, yy, zz, uu, vv, ww, **kw)
+    arrow = Arrow3D(x1, y1, z1, dx, dy, dz, **kw)
     p._ax.add_patch(arrow)
 
     if s.show_in_legend:
@@ -77,10 +78,11 @@ def _update_arrow3d(renderer, data, handle):
     arrow and add a new one.
     """
     p = renderer.plot
-    xx, yy, zz, uu, vv, ww = data
+    x1, y1, z1, x2, y2, z2 = data
+    dx, dy, dz = x2 - x1, y2 - y1, z2 - z1
     handle[0].remove()
     kw = handle[1]
-    arrow = Arrow3D(xx, yy, zz, uu, vv, ww, **kw)
+    arrow = Arrow3D(x1, y1, z1, dx, dy, dz, **kw)
     p._ax.add_patch(arrow)
     handle[0] = arrow
 

spb/series.py

@@ -3695,8 +3695,11 @@ def __init__(self, start, direction, label="", **kwargs):
         self.is_streamlines = kwargs.get("streamlines", False)
 
     def __str__(self):
+        pre = "3D " if self.is_3D else "2D "
+        start = tuple(self.start)
+        end = tuple(s + d for s, d in zip(start, self.direction))
         return self._str_helper(
-            f"2D arrow from {self.start} to {self.direction}"
+            pre + f"arrow from {start} to {end}"
         )
 
     def get_label(self, use_latex=False, wrapper="$%s$"):
@@ -3724,9 +3727,9 @@ def get_data(self):
 
         Returns
         =======
-        x, y : float
+        x1, y1, z1 [optional] : float
             Coordinates of the start position.
-        u, v : float
+        x2, y2, z2 [optional] : float
             Coordinates of the end position.
         """
         np = import_module('numpy')
@@ -3742,8 +3745,8 @@ def get_data(self):
             direction = np.array(
                 [t.evalf(subs=self.params) for t in direction], dtype=float)
 
-        direction += start
-        return self._apply_transform(*start, *direction)
+        end = start + direction
+        return self._apply_transform(*start, *end)
 
 
 class Arrow3DSeries(Arrow2DSeries):
@@ -3765,11 +3768,6 @@ def get_data(self):
         """
         return super().get_data()
 
-    def __str__(self):
-        return self._str_helper(
-            f"3D arrow from {self.start} to {self.direction}"
-        )
-
 
 class GridBase:
     """

tests/backends/test_matplotlib.py

@@ -2423,11 +2423,17 @@ def test_arrow_3d():
     assert len(p.ax.get_legend().legend_handles) == 1
     assert p.ax.get_legend().legend_handles[0].get_label() == "$test$"
     assert p.ax.get_legend().legend_handles[0].get_color() == "r"
+    # only way to test if it renders what it's supposed to
+    assert np.allclose(p.ax.patches[0]._xyz, [1, 2, 3])
+    assert np.allclose(p.ax.patches[0]._dxdydz, [4, 5, 6])
 
     p = make_test_arrow_3d(MB, "test", {"color": "r"}, False)
     p.fig
     assert len(p.ax.patches) == 1
     assert p.ax.get_legend() is None
+    # only way to test if it renders what it's supposed to
+    assert np.allclose(p.ax.patches[0]._xyz, [1, 2, 3])
+    assert np.allclose(p.ax.patches[0]._dxdydz, [4, 5, 6])
 
 
 @pytest.mark.skipif(ct is None, reason="control is not installed")

tests/test_series.py

@@ -4124,14 +4124,17 @@ def test_arrow2dserie(start, direc, label, rkw, sil, params):
     if not params:
         assert s.get_label(False) == (
             "(1.0, 2.0) -> (4.0, 6.0)" if not label else label)
+        assert str(s) == "2D arrow from (1.0, 2.0) to (4.0, 6.0)"
     else:
         assert s.get_label(False) == (
             "(j, k) -> (j + 3, k + 4)" if not label else label)
+        assert str(s) == "interactive 2D arrow from (j, k) to (j + 3, k + 4) and parameters (j, k)"
     assert s.rendering_kw == {} if not rkw else rkw
     assert s.is_interactive == (len(s.params) > 0)
     assert s.params == {} if not params else params
 
 
+
 @pytest.mark.parametrize(
     "start, direc, label, rkw, sil, params",
     [
@@ -4155,9 +4158,11 @@ def test_arrow3dserie(start, direc, label, rkw, sil, params):
     if not params:
         assert s.get_label(False) == (
             "(1.0, 2.0, 3.0) -> (5.0, 7.0, 9.0)" if not label else label)
+        assert str(s) == "3D arrow from (1.0, 2.0, 3.0) to (5.0, 7.0, 9.0)"
     else:
         assert s.get_label(False) == (
             "(j, k, l) -> (j + 4, k + 5, l + 6)" if not label else label)
+        assert str(s) == "interactive 3D arrow from (j, k, l) to (j + 4, k + 5, l + 6) and parameters (j, k, l)"
     assert s.rendering_kw == {} if not rkw else rkw
     assert s.is_interactive == (len(s.params) > 0)
     assert s.params == {} if not params else params