First motion blending sample implementation.

guillaumeblanc · Apr 23, 2024 · 08bdb67 · 08bdb67
1 parent 9f75da7
commit 08bdb67
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Showing 6 changed files with 561 additions and 25 deletions.
diff --git a/samples/CMakeLists.txt b/samples/CMakeLists.txt
@@ -12,6 +12,7 @@ add_subdirectory(blend)
 add_subdirectory(foot_ik)
 add_subdirectory(look_at)
 add_subdirectory(millipede)
+add_subdirectory(motion_blend)
 add_subdirectory(motion_extraction)
 add_subdirectory(motion_playback)
 add_subdirectory(multithread)

diff --git a/samples/framework/motion_utils.cc b/samples/framework/motion_utils.cc
@@ -103,26 +103,40 @@ bool SampleMotion(const MotionTrack& _tracks, float _ratio,
   return true;
 }
 
+void MotionDeltaAccumulator::Update(const ozz::math::Transform& _delta) {
+  Update(_delta, ozz::math::Quaternion::identity());
+}
+
+void MotionDeltaAccumulator::Update(const ozz::math::Transform& _delta,
+                                    const ozz::math::Quaternion& _rotation) {
+  // Accumulates rotation.
+  rotation_accum_ = Normalize(rotation_accum_ * _rotation);
+
+  // Updates current transform.
+  current.translation = current.translation +
+                        TransformVector(rotation_accum_, _delta.translation);
+  current.rotation = Normalize(current.rotation * _delta.rotation * _rotation);
+}
+void MotionDeltaAccumulator::Teleport(const ozz::math::Transform& _origin) {
+  current = _origin;
+
+  // Resets rotation accumulator.
+  rotation_accum_ = ozz::math::Quaternion::identity();
+}
+
 void MotionAccumulator::Update(const ozz::math::Transform& _new) {
   return Update(_new, ozz::math::Quaternion::identity());
 }
 
 // Accumulates motion deltas (new transform - last).
 void MotionAccumulator::Update(const ozz::math::Transform& _new,
                                const ozz::math::Quaternion& _delta_rotation) {
-  // Accumulates rotation.
-  // Normalizes to avoid accumulating error.
-  rotation_accum_ = Normalize(rotation_accum_ * _delta_rotation);
-
-  // Computes delta translation.
-  const auto delta_p = _new.translation - last.translation;
-  current.translation =
-      current.translation + TransformVector(rotation_accum_, delta_p);
+  // Computes delta.
+  delta.translation = _new.translation - last.translation;
+  delta.rotation = Conjugate(last.rotation) * _new.rotation;
 
-  // Computes delta rotation.
-  // Normalizes to avoid accumulating a denormalization error.
-  const auto delta_r = Conjugate(last.rotation) * _new.rotation;
-  current.rotation = Normalize(current.rotation * delta_r * _delta_rotation);
+  // Updates current transform based on computed delta.
+  MotionDeltaAccumulator::Update(delta, _delta_rotation);
 
   // Next time, delta will be computed from the _new transform.
   last = _new;
@@ -133,11 +147,13 @@ void MotionAccumulator::ResetOrigin(const ozz::math::Transform& _origin) {
 }
 
 void MotionAccumulator::Teleport(const ozz::math::Transform& _origin) {
+  MotionDeltaAccumulator::Teleport(_origin);
+
   // Resets current transform to new _origin
-  current = last = _origin;
+  last = current;
 
-  // Resets rotation accumulator.
-  rotation_accum_ = ozz::math::Quaternion::identity();
+  // No delta between last and current
+  delta = ozz::math::Transform::identity();
 }
 
 bool MotionSampler::Update(const MotionTrack& _motion, float _ratio,
@@ -154,10 +170,12 @@ bool MotionSampler::Update(const MotionTrack& _motion, float _ratio, int _loops,
     // motion done during the loop(s).
 
     // Uses a local accumulator to accumulate motion during loops.
-    MotionAccumulator local_accumulator{last, last};
+    MotionAccumulator local_accumulator;
+    local_accumulator.Teleport(last);
 
     for (; _loops; _loops > 0 ? --_loops : ++_loops) {
-      // Samples motion at loop end (or begin depending on playback direction).
+      // Samples motion at loop end (or begin depending on playback
+      // direction).
       if (!SampleMotion(_motion, _loops > 0 ? 1.f : 0.f, &sample)) {
         return false;
       }

diff --git a/samples/framework/motion_utils.h b/samples/framework/motion_utils.h
@@ -52,18 +52,35 @@ struct MotionTrack {
 // and _track must be non-nullptr.
 bool LoadMotionTrack(const char* _filename, MotionTrack* _track);
 
+struct MotionDeltaAccumulator {
+  void Update(const ozz::math::Transform& _delta);
+
+  void Update(const ozz::math::Transform& _delta,
+              const ozz::math::Quaternion& _rotation);
+
+  // Teleports accumulator to a new transform. This also resets the origin, so
+  // next delta is computed from the new origin.
+  void Teleport(const ozz::math::Transform& _origin);
+
+  // Character's current transform.
+  ozz::math::Transform current = ozz::math::Transform::identity();
+
+  // Accumulated rotation (since last teleport).
+  ozz::math::Quaternion rotation_accum_ = ozz::math::Quaternion::identity();
+};
+
 // Helper object that manages motion accumulation to compute character's
 // transform.
-struct MotionAccumulator {
+struct MotionAccumulator : public MotionDeltaAccumulator {
   //  Accumulates motion delta (new - last) and updates current transform.
   void Update(const ozz::math::Transform& _new);
 
   //  Accumulates motion delta (new - last) and updates current transform.
-  // _delta_rotation is the rotation to pply to deform the path since last
+  // _delta_rotation is the rotation to apply to deform the path since last
   // update. Hence, user is responsible for taking care of applying delta time
   // if he wants to achieve a specific angular speed.
   void Update(const ozz::math::Transform& _new,
-              const ozz::math::Quaternion& _delta_rotation);
+              const ozz::math::Quaternion& _rotation);
 
   // Tells the accumulator that the _new transform is the new origin.
   // This is useful when animation loops, so next delta is computed from the new
@@ -77,11 +94,8 @@ struct MotionAccumulator {
   // Last value sample from the motion track, used to compute delta.
   ozz::math::Transform last = ozz::math::Transform::identity();
 
-  // Character's current transform.
-  ozz::math::Transform current = ozz::math::Transform::identity();
-
-  // Accumulated rotation (since last teleport).
-  ozz::math::Quaternion rotation_accum_ = ozz::math::Quaternion::identity();
+  // Delta transformation between last and current frame.
+  ozz::math::Transform delta = ozz::math::Transform::identity();
 };
 
 // Helper object samples a motion track to update a MotionAccumulator.

diff --git a/samples/motion_blend/CMakeLists.txt b/samples/motion_blend/CMakeLists.txt
@@ -0,0 +1,74 @@
+# Generates sample data
+
+add_custom_command(
+  DEPENDS $<$<BOOL:${ozz_build_fbx}>:BUILD_DATA>
+          "${CMAKE_CURRENT_LIST_DIR}/README.md"
+          "${ozz_media_directory}/bin/pab_skeleton.ozz"
+          "${ozz_media_directory}/bin/pab_walk_no_motion.ozz"
+          "${ozz_media_directory}/bin/pab_jog_no_motion.ozz"
+          "${ozz_media_directory}/bin/pab_jog_no_motion.ozz"
+          "${ozz_media_directory}/bin/pab_walk_motion_track.ozz"
+          "${ozz_media_directory}/bin/pab_jog_motion_track.ozz"
+          "${ozz_media_directory}/bin/pab_jog_motion_track.ozz"
+  OUTPUT  "${CMAKE_CURRENT_BINARY_DIR}/README.md"
+          "${CMAKE_CURRENT_BINARY_DIR}/media/skeleton.ozz"
+          "${CMAKE_CURRENT_BINARY_DIR}/media/animation1.ozz"
+          "${CMAKE_CURRENT_BINARY_DIR}/media/animation2.ozz"
+          "${CMAKE_CURRENT_BINARY_DIR}/media/animation3.ozz"
+          "${CMAKE_CURRENT_BINARY_DIR}/media/motion1.ozz"
+          "${CMAKE_CURRENT_BINARY_DIR}/media/motion2.ozz"
+          "${CMAKE_CURRENT_BINARY_DIR}/media/motion3.ozz"
+  COMMAND ${CMAKE_COMMAND} -E make_directory media
+  COMMAND ${CMAKE_COMMAND} -E copy "${CMAKE_CURRENT_LIST_DIR}/README.md" .
+  COMMAND ${CMAKE_COMMAND} -E copy "${ozz_media_directory}/bin/pab_skeleton.ozz" "./media/skeleton.ozz"
+  COMMAND ${CMAKE_COMMAND} -E copy "${ozz_media_directory}/bin/pab_walk_no_motion.ozz" "./media/animation1.ozz"
+  COMMAND ${CMAKE_COMMAND} -E copy "${ozz_media_directory}/bin/pab_jog_no_motion.ozz" "./media/animation2.ozz"
+  COMMAND ${CMAKE_COMMAND} -E copy "${ozz_media_directory}/bin/pab_run_no_motion.ozz" "./media/animation3.ozz"
+  COMMAND ${CMAKE_COMMAND} -E copy "${ozz_media_directory}/bin/pab_walk_motion_track.ozz" "./media/motion1.ozz"
+  COMMAND ${CMAKE_COMMAND} -E copy "${ozz_media_directory}/bin/pab_jog_motion_track.ozz" "./media/motion2.ozz"
+  COMMAND ${CMAKE_COMMAND} -E copy "${ozz_media_directory}/bin/pab_run_motion_track.ozz" "./media/motion3.ozz"
+  VERBATIM)
+
+# Adds sample executable
+add_executable(sample_motion_blend
+sample_motion_blend.cc
+  "${CMAKE_CURRENT_BINARY_DIR}/README.md"
+  "${CMAKE_CURRENT_BINARY_DIR}/media/skeleton.ozz"
+  "${CMAKE_CURRENT_BINARY_DIR}/media/animation1.ozz"
+  "${CMAKE_CURRENT_BINARY_DIR}/media/animation2.ozz"
+  "${CMAKE_CURRENT_BINARY_DIR}/media/animation3.ozz"
+  "${CMAKE_CURRENT_BINARY_DIR}/media/motion1.ozz"
+  "${CMAKE_CURRENT_BINARY_DIR}/media/motion2.ozz"
+  "${CMAKE_CURRENT_BINARY_DIR}/media/motion3.ozz")
+
+target_link_libraries(sample_motion_blend
+  sample_framework)
+target_copy_shared_libraries(sample_motion_blend)
+
+set_target_properties(sample_motion_blend
+  PROPERTIES FOLDER "samples")
+
+if(EMSCRIPTEN)
+  # Resource files are embedded to the output file with emscripten
+  set_target_properties(sample_motion_blend
+    PROPERTIES LINK_FLAGS "--embed-file media --embed-file README.md")
+
+  install(FILES
+    ${CMAKE_CURRENT_BINARY_DIR}/sample_motion_blend.html
+    ${CMAKE_CURRENT_BINARY_DIR}/sample_motion_blend.js
+    ${CMAKE_CURRENT_BINARY_DIR}/sample_motion_blend.wasm
+    DESTINATION bin/samples/motion_blend)
+else()
+  install(TARGETS sample_motion_blend DESTINATION bin/samples/motion_blend)
+  install(DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/media DESTINATION bin/samples/motion_blend)
+  install(FILES ${CMAKE_CURRENT_BINARY_DIR}/README.md DESTINATION bin/samples/motion_blend)
+endif(EMSCRIPTEN)
+
+add_test(NAME sample_motion_blend COMMAND sample_motion_blend "--max_idle_loops=${ozz_sample_testing_loops}" $<$<BOOL:${ozz_run_tests_headless}>:--norender>)
+add_test(NAME sample_motion_blend_path COMMAND sample_motion_blend "--skeleton=media/skeleton.ozz" "--animation1=media/animation1.ozz" "--animation2=media/animation2.ozz"  "--animation3=media/animation3.ozz" "--max_idle_loops=${ozz_sample_testing_loops}" $<$<BOOL:${ozz_run_tests_headless}>:--norender>)
+add_test(NAME sample_motion_blend_invalid_skeleton_path COMMAND sample_motion_blend "--skeleton=media/bad_skeleton.ozz" $<$<BOOL:${ozz_run_tests_headless}>:--norender>)
+set_tests_properties(sample_motion_blend_invalid_skeleton_path PROPERTIES WILL_FAIL true)
+add_test(NAME sample_motion_blend_invalid_animation_path COMMAND sample_motion_blend "--animation1=media/bad_animation.ozz" $<$<BOOL:${ozz_run_tests_headless}>:--norender>)
+set_tests_properties(sample_motion_blend_invalid_animation_path PROPERTIES WILL_FAIL true)
+add_test(NAME sample_motion_blend_invalid_motion_path COMMAND sample_motion_blend "--motion2=media/bad_animation.ozz" $<$<BOOL:${ozz_run_tests_headless}>:--norender>)
+set_tests_properties(sample_motion_blend_invalid_motion_path PROPERTIES WILL_FAIL true)
diff --git a/samples/motion_blend/README.md b/samples/motion_blend/README.md
@@ -0,0 +1,9 @@
+# Ozz-animation sample: Animation blending
+
+## Description
+
+## Concept
+
+## Sample usage
+
+## Implementation