New mobject: ImplicitSurface for implicit 3D surface rendering

example_scenes/basic.py

@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 
-
 from manim import *
+from manim.mobject.three_d.implicit_surface import ImplicitSurface
 
 # To watch one of these scenes, run the following:
 # python --quality m manim -p example_scenes.py SquareToCircle
@@ -176,4 +176,16 @@ def construct(self):
         self.add(grp)
 
 
+class ExampleImplicitSurface(ThreeDScene):
+    def construct(self):
+        self.set_camera_orientation(phi=70 * DEGREES, theta=45 * DEGREES)
+        surface = ImplicitSurface(
+            lambda x, y, z: x**2 + y**2 + z**2 - 1,
+            resolution=30,
+            color=BLUE,
+        )
+        self.add(surface)
+        self.wait()
+
+
 # See many more examples at https://docs.manim.community/en/stable/examples.html

manim/mobject/three_d/implicit_surface.py

@@ -0,0 +1,69 @@
+from __future__ import annotations
+
+import numpy as np
+from skimage import measure
+
+from manim import *
+
+
+class ImplicitSurface(ThreeDVMobject):
+    """Renderiza uma isosuperfície implícita usando Marching Cubes.
+
+    Parameters
+    ----------
+    func : Callable[[float, float, float], float]
+        Função implícita f(x,y,z). A superfície é definida onde f(x,y,z) = isolevel.
+    resolution : int, default=25
+        Número de divisões por eixo.
+    isolevel : float, default=0.0
+        Nível da isosuperfície.
+    x_range, y_range, z_range : list[float], default=[-2, 2]
+        Intervalos de amostragem.
+    color : Color, default=BLUE
+        Cor da superfície.
+    **kwargs
+        Argumentos adicionais para ThreeDVMobject.
+    """
+
+    def __init__(
+        self,
+        func,
+        resolution=25,
+        isolevel=0.0,
+        x_range=[-2, 2],
+        y_range=[-2, 2],
+        z_range=[-2, 2],
+        color=BLUE,
+        **kwargs,
+    ):
+        super().__init__(**kwargs)
+
+        # Gera a grade 3D:
+        x = np.linspace(x_range[0], x_range[1], resolution)
+        y = np.linspace(y_range[0], y_range[1], resolution)
+        z = np.linspace(z_range[0], z_range[1], resolution)
+        X, Y, Z = np.meshgrid(x, y, z, indexing="ij")
+        values = func(X, Y, Z)
+
+        # Extrai a malha:
+        verts, faces, _, _ = measure.marching_cubes(values, level=isolevel)
+
+        # Normaliza para o domínio real:
+        scale_x = (x_range[1] - x_range[0]) / resolution
+        scale_y = (y_range[1] - y_range[0]) / resolution
+        scale_z = (z_range[1] - z_range[0]) / resolution
+        verts = np.array(
+            [
+                [
+                    x_range[0] + v[0] * scale_x,
+                    y_range[0] + v[1] * scale_y,
+                    z_range[0] + v[2] * scale_z,
+                ]
+                for v in verts
+            ]
+        )
+
+        # Constrói os polígonos:
+        for face in faces:
+            tri = [verts[i] for i in face]
+            self.add(Polygon(*tri, color=color, fill_opacity=1))

tests/test_implicit_surface.py

@@ -0,0 +1,12 @@
+from manim import *
+from manim.mobject.three_d.implicit_surface import ImplicitSurface
+
+
+class TestSurfaceScene(ThreeDScene):
+    def construct(self):
+        self.set_camera_orientation(phi=70 * DEGREES, theta=45 * DEGREES)
+        surface = ImplicitSurface(
+            lambda x, y, z, r=0.7: x**2 + y**2 - r**2, resolution=20, color=WHITE
+        )
+        self.add(surface)
+        self.wait()

tests/test_implicit_surface360.py

@@ -0,0 +1,16 @@
+from manim import *
+from manim.mobject.three_d.implicit_surface import ImplicitSurface
+
+
+class TestSurface360(ThreeDScene):
+    def construct(self):
+        self.set_camera_orientation(phi=70 * DEGREES, theta=0)
+
+        surface = ImplicitSurface(
+            lambda x, y, z: x**2 + y**2 + z**2 - 1, resolution=20, color=BLUE
+        )
+        self.add(surface)
+
+        self.begin_ambient_camera_rotation(rate=PI / 4)
+        self.wait(8)
+        self.stop_ambient_camera_rotation()