Adds multiply function to dual_quaternion module.

PiperOrigin-RevId: 379060199

Author: G4G

tensorflow_graphics/geometry/transformation/dual_quaternion.py

@@ -78,5 +78,51 @@ def conjugate(dual_quaternion: type_alias.TensorLike,
                      axis=-1)
 
 
+def multiply(dual_quaternion1: type_alias.TensorLike,
+             dual_quaternion2: type_alias.TensorLike,
+             name: str = "dual_quaternion_multiply"):
+  """Multiplies two dual quaternions.
+
+  Note:
+    In the following, A1 to An are optional batch dimensions.
+
+  Args:
+    dual_quaternion1:  A TensorLike of shape `[A1, ..., An, 8]`, where the last
+      dimension represents a dual quaternion.
+    dual_quaternion2:  A TensorLike of shape `[A1, ..., An, 8]`, where the last
+      dimension represents a dual quaternion.
+    name: A name for this op that defaults to "dual_quaternion_multiply".
+
+  Returns:
+    A tensor of shape `[A1, ..., An, 8]` representing dual quaternions.
+  """
+  with tf.name_scope(name):
+    dual_quaternion1 = tf.convert_to_tensor(value=dual_quaternion1)
+    dual_quaternion2 = tf.convert_to_tensor(value=dual_quaternion2)
+
+    shape.check_static(
+        tensor=dual_quaternion1,
+        tensor_name="dual_quaternion1",
+        has_dim_equals=(-1, 8))
+    shape.check_static(
+        tensor=dual_quaternion2,
+        tensor_name="dual_quaternion2",
+        has_dim_equals=(-1, 8))
+
+    dual_quaternion1_real, dual_quaternion1_dual = tf.split(
+        dual_quaternion1, (4, 4), axis=-1)
+    dual_quaternion2_real, dual_quaternion2_dual = tf.split(
+        dual_quaternion2, (4, 4), axis=-1)
+
+    dual_quaternion_output_real = quaternion.multiply(dual_quaternion1_real,
+                                                      dual_quaternion2_real)
+    dual_quaternion_output_dual = (
+        quaternion.multiply(dual_quaternion1_real, dual_quaternion2_dual) +
+        quaternion.multiply(dual_quaternion1_dual, dual_quaternion2_real))
+
+    return tf.concat((dual_quaternion_output_real, dual_quaternion_output_dual),
+                     axis=-1)
+
+
 # API contains all public functions and classes.
 __all__ = export_api.get_functions_and_classes()

tensorflow_graphics/geometry/transformation/tests/dual_quaternion_test.py

@@ -15,7 +15,7 @@
 
 from absl.testing import flagsaver
 from absl.testing import parameterized
-import tensorflow.compat.v2 as tf
+import tensorflow as tf
 
 from tensorflow_graphics.geometry.transformation import dual_quaternion
 from tensorflow_graphics.geometry.transformation.tests import test_helpers
@@ -29,30 +29,25 @@ class DualQuaternionTest(test_case.TestCase):
       ((None, 8),),
   )
   def test_conjugate_exception_not_raised(self, *shape):
-    """Tests that the shape exceptions of conjugate are not raised."""
     self.assert_exception_is_not_raised(dual_quaternion.conjugate, shape)
 
   @parameterized.parameters(
       ("must have exactly 8 dimensions", (3,)),)
   def test_conjugate_exception_raised(self, error_msg, *shape):
-    """Tests that the shape exceptions are raised."""
     self.assert_exception_is_raised(dual_quaternion.conjugate, error_msg, shape)
 
   @flagsaver.flagsaver(tfg_add_asserts_to_graph=False)
   def test_conjugate_jacobian_preset(self):
-    """Tests the Jacobian of the conjugate function."""
     x_init = test_helpers.generate_preset_test_dual_quaternions()
     self.assert_jacobian_is_correct_fn(dual_quaternion.conjugate, [x_init])
 
   @flagsaver.flagsaver(tfg_add_asserts_to_graph=False)
   def test_conjugate_jacobian_random(self):
-    """Tests the Jacobian of the conjugate function."""
     x_init = test_helpers.generate_random_test_dual_quaternions()
     self.assert_jacobian_is_correct_fn(dual_quaternion.conjugate, [x_init])
 
   @flagsaver.flagsaver(tfg_add_asserts_to_graph=False)
   def test_conjugate_preset(self):
-    """Tests if the conjugate function is providing correct results."""
     x_init = test_helpers.generate_preset_test_dual_quaternions()
     x = tf.convert_to_tensor(value=x_init)
     y = tf.convert_to_tensor(value=x_init)
@@ -68,3 +63,37 @@ def test_conjugate_preset(self):
 
     self.assertAllEqual(x_real, y_real)
     self.assertAllEqual(x_dual, y_dual)
+
+  @parameterized.parameters(
+      ((8,), (8,)),
+      ((None, 8), (None, 8)),
+  )
+  def test_multiply_exception_not_raised(self, *shapes):
+    self.assert_exception_is_not_raised(dual_quaternion.multiply, shapes)
+
+  @parameterized.parameters(
+      ("must have exactly 8 dimensions", (5,), (6,)),
+      ("must have exactly 8 dimensions", (7,), (8,)),
+  )
+  def test_multiply_exception_raised(self, error_msg, *shape):
+    self.assert_exception_is_raised(dual_quaternion.multiply, error_msg, shape)
+
+  @flagsaver.flagsaver(tfg_add_asserts_to_graph=False)
+  def test_multiply_jacobian_preset(self):
+    x_1_init = test_helpers.generate_preset_test_dual_quaternions()
+    x_2_init = test_helpers.generate_preset_test_dual_quaternions()
+
+    self.assert_jacobian_is_correct_fn(dual_quaternion.multiply,
+                                       [x_1_init, x_2_init])
+
+  @flagsaver.flagsaver(tfg_add_asserts_to_graph=False)
+  def test_multiply_jacobian_random(self):
+    x_1_init = test_helpers.generate_random_test_dual_quaternions()
+    x_2_init = test_helpers.generate_random_test_dual_quaternions()
+
+    self.assert_jacobian_is_correct_fn(dual_quaternion.multiply,
+                                       [x_1_init, x_2_init])
+
+
+if __name__ == "__main__":
+  test_case.main()