Added LockTranslationNode.

CMakeLists.txt

@@ -48,6 +48,7 @@ add_library(AnimTestbedCode OBJECT
         src/AnimNodes/AnimSamplerNode.cc
         src/AnimNodes/SpeedScaleNode.cc
         src/AnimNodes/BlendNode.cc
+        src/AnimNodes/LockTranslationNode.cc
         src/AnimationController.cc
         3rdparty/imgui/imgui.cpp
         3rdparty/imgui/imgui_draw.cpp

src/AnimNodes/AnimSamplerNode.cc

@@ -18,9 +18,8 @@ void AnimSamplerNode::SetAnimation(ozz::animation::Animation* animation) {
   m_sampling_cache.Resize(num_joints);
 }
 
-
-
-void AnimSamplerNode::Evaluate(ozz::vector<ozz::math::SoaTransform>* local_matrices) {
+void AnimSamplerNode::Evaluate(
+    ozz::vector<ozz::math::SoaTransform>* local_matrices) {
   ozz::animation::SamplingJob sampling_job;
   sampling_job.animation = m_animation;
   sampling_job.cache = &m_sampling_cache;
@@ -31,29 +30,22 @@ void AnimSamplerNode::Evaluate(ozz::vector<ozz::math::SoaTransform>* local_matri
   }
 }
 
-
-
 void AnimSamplerNode::DrawDebugUi() {
-  std::string node_name = "AnimSamplerNode: " + m_name;
-  if (ImGui::TreeNode(node_name.c_str())) {
-    const SkinnedMesh* skinned_mesh = m_animation_controller->m_skinned_mesh;
-    int anim_count = skinned_mesh->m_animation_names.size();
-    const char* items[255] = {0};
-    int item_current = 0;
-    for (int i = 0; i < anim_count; i++) {
-      items[i] = skinned_mesh->m_animation_names[i].c_str();
-      if (skinned_mesh->m_animations[i] == m_animation) {
-        item_current = i;
-      }
+  const SkinnedMesh* skinned_mesh = m_animation_controller->m_skinned_mesh;
+  int anim_count = skinned_mesh->m_animation_names.size();
+  const char* items[255] = {0};
+  int item_current = 0;
+  for (int i = 0; i < anim_count; i++) {
+    items[i] = skinned_mesh->m_animation_names[i].c_str();
+    if (skinned_mesh->m_animations[i] == m_animation) {
+      item_current = i;
     }
-
-    if (ImGui::Combo("Animation", &item_current, items, anim_count)) {
-      m_animation = skinned_mesh->m_animations[item_current];
-    }
-    ImGui::Checkbox("Override", &m_override_ratio);
-    ImGui::SameLine();
-    ImGui::SliderFloat("Ratio", &m_anim_ratio, 0.f, 1.f);
-
-    ImGui::TreePop();
   }
+
+  if (ImGui::Combo("Animation", &item_current, items, anim_count)) {
+    m_animation = skinned_mesh->m_animations[item_current];
+  }
+  ImGui::Checkbox("Override", &m_override_ratio);
+  ImGui::SameLine();
+  ImGui::SliderFloat("Ratio", &m_anim_ratio, 0.f, 1.f);
 }

src/AnimNodes/BlendNode.cc

@@ -49,14 +49,6 @@ void BlendNode::Evaluate(ozz::vector<ozz::math::SoaTransform>* local_matrices) {
 }
 
 void BlendNode::DrawDebugUi() {
-  std::string node_name = "BlendNode: " + m_name;
-  if (ImGui::TreeNode(node_name.c_str())) {
-    ImGui::Text("Input A:");
-    m_input_A->DrawDebugUi();
-    ImGui::Text("Input B:");
-    m_input_B->DrawDebugUi();
-    ImGui::SliderFloat("Weight", &m_weight, 0.f, 1.f);
-    ImGui::Checkbox("Sync Inputs", &m_sync_inputs);
-    ImGui::TreePop();
-  }
+  ImGui::SliderFloat("Weight", &m_weight, 0.f, 1.f);
+  ImGui::Checkbox("Sync Inputs", &m_sync_inputs);
 }

src/AnimNodes/LockTranslationNode.cc

@@ -0,0 +1,59 @@
+//
+// Created by martin on 16.11.21.
+//
+
+#include "LockTranslationNode.h"
+
+#include <imgui.h>
+#include "ozz/base/maths/soa_transform.h"
+
+void LockTranslationNode::Evaluate(
+    ozz::vector<ozz::math::SoaTransform>* local_matrices) {
+  m_input->Evaluate(local_matrices);
+  ozz::math::SoaFloat3 translation = (*local_matrices)[m_locked_bone_index].translation;
+  float x[4];
+  float y[4];
+  float z[4];
+  _mm_store_ps(x, translation.x);
+  _mm_store_ps(y, translation.y);
+  _mm_store_ps(z, translation.z);
+
+  if (m_lock_x) {
+    x[0] = 0.f;
+  }
+
+  if (m_lock_y) {
+    y[0] = 0.f;
+  }
+
+  if (m_lock_z) {
+    z[0] = 0.f;
+  }
+
+  translation.x = _mm_load_ps(x);
+  translation.y = _mm_load_ps(y);
+  translation.z = _mm_load_ps(z);
+
+  //translation = ozz::math::SoaFloat3::zero();
+//  ozz::math::SetX(translation, 0.f);
+//  ozz::math::SetZ(translation, 0.f);
+   (*local_matrices)[m_locked_bone_index].translation = translation;
+}
+
+void LockTranslationNode::DrawDebugUi() {
+  const ozz::animation::Skeleton& skeleton = m_animation_controller->m_skinned_mesh->m_skeleton;
+  ozz::span<const char* const> joint_names = skeleton.joint_names();
+
+  const char* items[255] = {0};
+  int item_current = 0;
+  for (int i = 0; i < joint_names.size(); i++) {
+    items[i] = joint_names[i];
+  }
+
+  ImGui::Combo("Bone", &m_locked_bone_index, items, joint_names.size());
+  ImGui::Checkbox("Lock X", &m_lock_x);
+  ImGui::Checkbox("Lock Y", &m_lock_y);
+  ImGui::Checkbox("Lock Z", &m_lock_z);
+
+
+}

src/AnimNodes/LockTranslationNode.h

@@ -0,0 +1,52 @@
+//
+// Created by martin on 16.11.21.
+//
+
+#ifndef ANIMTESTBED_LOCKBONES_H
+#define ANIMTESTBED_LOCKBONES_H
+
+#include "../AnimNode.h"
+
+struct LockTranslationNode : public AnimNode {
+  LockTranslationNode(AnimationController* animation_controller)
+      : AnimNode(animation_controller),
+        m_input(nullptr),
+        m_locked_bone_index(0),
+        m_lock_x(false),
+        m_lock_y(false),
+        m_lock_z(false) {}
+
+  virtual ~LockTranslationNode() {}
+
+  AnimNode* m_input;
+  int m_locked_bone_index;
+  bool m_lock_x;
+  bool m_lock_y;
+  bool m_lock_z;
+
+  virtual void Reset() { m_current_time = 0.f; }
+
+  virtual void UpdateIsSynced(bool is_synced) override {
+    m_is_time_synced = is_synced;
+
+    m_input->UpdateIsSynced(m_is_time_synced);
+  }
+
+  virtual void EvalAnimDuration() override {
+    m_anim_duration = m_input->m_anim_duration;
+  }
+
+  virtual void UpdateTime(float dt) { m_input->UpdateTime(dt); }
+
+  virtual void Evaluate(
+      ozz::vector<ozz::math::SoaTransform>* local_matrices) override;
+
+  virtual void GetInputNodes(
+      std::vector<AnimNode*>& input_nodes) const override {
+    input_nodes.push_back(m_input);
+  };
+
+  virtual void DrawDebugUi() override;
+};
+
+#endif  //ANIMTESTBED_LOCKBONES_H

src/AnimNodes/SpeedScaleNode.cc

@@ -7,21 +7,14 @@
 #include <imgui.h>
 
 void SpeedScaleNode::DrawDebugUi() {
-  std::string node_name = "SpeedScaleNode: " + m_name;
-  if (ImGui::TreeNode(node_name.c_str())) {
-    bool is_negative = m_time_scale < 0.f;
-    if (ImGui::Checkbox("Reverse Time", &is_negative)) {
-      m_time_scale = m_time_scale * -1.f;
-    }
-
-    // ensure m_time_scale is positive
-    m_time_scale = m_time_scale * (is_negative ? -1.f : 1.f);
-    ImGui::SliderFloat("Time Scale", &m_time_scale, 0.01f, 5.f);
-    // and back to the original negative or positive sign
-    m_time_scale = m_time_scale * (is_negative ? -1.f : 1.f);
-
-    m_input_node->DrawDebugUi();
-
-    ImGui::TreePop();
+  bool is_negative = m_time_scale < 0.f;
+  if (ImGui::Checkbox("Reverse Time", &is_negative)) {
+    m_time_scale = m_time_scale * -1.f;
   }
+
+  // ensure m_time_scale is positive
+  m_time_scale = m_time_scale * (is_negative ? -1.f : 1.f);
+  ImGui::SliderFloat("Time Scale", &m_time_scale, 0.01f, 5.f);
+  // and back to the original negative or positive sign
+  m_time_scale = m_time_scale * (is_negative ? -1.f : 1.f);
 }

src/AnimationController.cc

@@ -5,7 +5,6 @@
 #include "AnimationController.h"
 
 #include <imgui.h>
-#include <ozz/animation/runtime/blending_job.h>
 #include <ozz/animation/runtime/local_to_model_job.h>
 #include <ozz/animation/runtime/sampling_job.h>
 
@@ -13,6 +12,7 @@
 
 #include "AnimNodes/AnimSamplerNode.h"
 #include "AnimNodes/BlendNode.h"
+#include "AnimNodes/LockTranslationNode.h"
 #include "AnimNodes/SpeedScaleNode.h"
 #include "SkinnedMesh.h"
 
@@ -54,15 +54,18 @@ AnimationController::AnimationController(SkinnedMesh* skinned_mesh)
   speed_node1->m_input_node = blend_node;
   m_anim_nodes.push_back(speed_node1);
 
-  m_output_node = speed_node1;
+  LockTranslationNode* lock_node = new LockTranslationNode(this);
+  lock_node->m_name = "LockNode0";
+  lock_node->m_locked_bone_index = 0;
+  lock_node->m_input = speed_node1;
+
+  m_output_node = lock_node;
 
   UpdateOrderedNodes();
 
   m_output_node->Reset();
 }
 
-
-
 AnimationController::~AnimationController() {
   while (m_anim_nodes.size() > 0) {
     delete m_anim_nodes[m_anim_nodes.size() - 1];
@@ -97,9 +100,7 @@ void AnimationController::UpdateOrderedNodes() {
   }
 }
 
-void AnimationController::UpdateBlendLogic() {
-
-}
+void AnimationController::UpdateBlendLogic() {}
 
 void AnimationController::UpdateTime(float dt) {
   if (m_output_node == nullptr) {
@@ -121,8 +122,6 @@ void AnimationController::UpdateTime(float dt) {
   m_output_node->UpdateTime(dt);
 }
 
-
-
 void AnimationController::Evaluate() {
   if (m_output_node == nullptr) {
     return;
@@ -137,8 +136,6 @@ void AnimationController::Evaluate() {
   ltm_job.Run();
 };
 
-
-
 void AnimationController::DrawDebugUi() {
   ImGui::SetNextWindowSize(ImVec2(500, 300), ImGuiCond_FirstUseEver);
   ImGui::Begin("AnimationController");
@@ -147,46 +144,59 @@ void AnimationController::DrawDebugUi() {
     ResetAnims();
   }
 
-  if (m_output_node && ImGui::TreeNode("Output")) {
-    m_output_node->DrawDebugUi();
+  ImVec2 node_size(200, 100);
+  for (int i = 0; i < m_ordered_nodes.size(); i++) {
+    AnimNode* node = m_ordered_nodes[i];
 
-    ImGui::TreePop();
+    ImGui::SetNextWindowSize(node_size, ImGuiCond_FirstUseEver);
+    ImGui::SetNextWindowPos(
+        ImVec2((m_ordered_nodes.size() - 1 - i) * node_size.x - i * 10, 300),
+        ImGuiCond_FirstUseEver);
+    ImGui::Begin(node->m_name.c_str());
+    node->DrawDebugUi();
+    ImGui::End();
   }
 
-  if (m_output_node && ImGui::TreeNode("Nodes")) {
-    ImGui::Columns(4, "NodeOverview"); // 4-ways, with border
-    ImGui::Separator();
-    ImGui::Text("Name"); ImGui::NextColumn();
-    ImGui::Text("Synced"); ImGui::NextColumn();
-    ImGui::Text("Duration"); ImGui::NextColumn();
-    ImGui::Text("Time"); ImGui::NextColumn();
+  ImGui::Columns(4, "Node States");  // 4-ways, with border
+  ImGui::Separator();
+  ImGui::Text("Name");
+  ImGui::NextColumn();
+  ImGui::Text("Synced");
+  ImGui::NextColumn();
+  ImGui::Text("Duration");
+  ImGui::NextColumn();
+  ImGui::Text("Time");
+  ImGui::NextColumn();
 
-    ImGui::Separator();
-    static int selected = -1;
+  ImGui::Separator();
+  static int selected = -1;
 
-    for (int i = 0; i < m_ordered_nodes.size(); i++) {
-      AnimNode* node = m_ordered_nodes[i];
-      if (ImGui::Selectable(node->m_name.c_str(), selected == i, ImGuiSelectableFlags_SpanAllColumns))
-        selected = i;
-      bool hovered = ImGui::IsItemHovered();
-      ImGui::NextColumn();
+  for (int i = 0; i < m_ordered_nodes.size(); i++) {
+    AnimNode* node = m_ordered_nodes[i];
+    if (ImGui::Selectable(
+            node->m_name.c_str(),
+            selected == i,
+            ImGuiSelectableFlags_SpanAllColumns))
+      selected = i;
+    bool hovered = ImGui::IsItemHovered();
+    ImGui::NextColumn();
 
-      ImGui::Text(node->m_is_time_synced ? "X" : "-"); ImGui::NextColumn();
+    ImGui::Text(node->m_is_time_synced ? "X" : "-");
+    ImGui::NextColumn();
 
-      ImGui::PushID((void*)&node->m_anim_duration);
-      ImGui::Text("%2.3f", node->m_anim_duration);      ImGui::NextColumn();
-      ImGui::PopID();
+    ImGui::PushID((void*)&node->m_anim_duration);
+    ImGui::Text("%2.3f", node->m_anim_duration);
+    ImGui::NextColumn();
+    ImGui::PopID();
 
-      ImGui::PushID((void*)&node->m_current_time);
-      ImGui::Text("%2.3f", node->m_current_time);      ImGui::NextColumn();
-      ImGui::PopID();
-    }
-
-    ImGui::Columns(1);
-    ImGui::Separator();
-
-    ImGui::TreePop();
+    ImGui::PushID((void*)&node->m_current_time);
+    ImGui::Text("%2.3f", node->m_current_time);
+    ImGui::NextColumn();
+    ImGui::PopID();
   }
 
+  ImGui::Columns(1);
+  ImGui::Separator();
+
   ImGui::End();
 }

src/SkinnedMesh.h

@@ -25,35 +25,90 @@ constexpr int cSyncTrackMaxIntervals = 8;
 struct SyncTrack {
   float m_duration;
   int m_num_intervals;
+  float m_sync_markers[cSyncTrackMaxIntervals];
+  float m_interval_start[cSyncTrackMaxIntervals];
+  float m_interval_end[cSyncTrackMaxIntervals];
   float m_interval_durations[cSyncTrackMaxIntervals];
 
-  float ConvertAbsTimeToSyncTime (float abs_time) {
-    float sync_time = fmodf (abs_time, m_duration) / m_duration;
+  void CalcIntervals() {
+    int i;
 
-    int interval_index = 0;
-    while (sync_time < m_interval_durations[interval_index]) {
-      sync_time -= m_interval_durations[interval_index];
-      interval_index ++;
+    if (m_num_intervals == 0) {
+      m_num_intervals = 1;
+      m_interval_start[0] = 0.f;
+      m_interval_end[0] = 1.f;
+    } else {
+      for (i = 0; i < m_num_intervals; i++) {
+        int end_index = i < m_num_intervals - 1 ? i + 1 : 0;
+
+        m_interval_start[i] = m_sync_markers[i];
+        m_interval_end[i] = m_sync_markers[end_index];
+
+        if (m_interval_end[i] > m_interval_start[i]) {
+          m_interval_durations[i] = m_interval_end[i] - m_interval_start[i];
+        } else {
+          m_interval_durations[i] =
+              m_interval_end[i] + (1. - m_interval_start[i]);
+        }
+      }
     }
   }
 
-  static SyncTrack Blend(float weight, const SyncTrack& track_A, const SyncTrack& track_B) {
-    SyncTrack result;
+  float CalcSyncFromAbsTime(float abs_time) {
+    float sync_time = fmodf(abs_time, m_duration) / m_duration;
 
-    assert (track_A.m_num_intervals == track_B.m_num_intervals);
+    int interval_index = 0;
+    while (sync_time >= m_interval_durations[interval_index]) {
+      sync_time -= m_interval_durations[interval_index];
+      interval_index++;
+    }
+
+    return float(interval_index)
+           + sync_time / m_interval_durations[interval_index];
+  }
+
+  float CalcRatioFromSyncTime(float sync_time) {
+    float interval_ratio = fmodf(sync_time, 1.0f);
+    int interval = int(sync_time - interval_ratio);
+
+    return fmodf(
+        m_interval_start[interval]
+            + m_interval_durations[interval] * interval_ratio,
+        1.0f);
+  }
+
+  static SyncTrack
+  Blend(float weight, const SyncTrack& track_A, const SyncTrack& track_B) {
+    assert(track_A.m_num_intervals == track_B.m_num_intervals);
+
+    SyncTrack result;
     result.m_num_intervals = track_A.m_num_intervals;
 
-    result.m_duration = (1.0f - weight) * track_A.m_duration + weight * track_B.m_duration;
+    result.m_duration =
+        (1.0f - weight) * track_A.m_duration + weight * track_B.m_duration;
 
     for (int i = 0; i < result.m_num_intervals; i++) {
-      result.m_interval_durations[i] = (1.0f - weight) * track_A.m_interval_durations[i] + weight * track_B.m_interval_durations[i];
+      result.m_interval_durations[i] =
+          (1.0f - weight) * track_A.m_interval_durations[i]
+          + weight * track_B.m_interval_durations[i];
+
+      result.m_interval_start[i] =
+          (1.0f - weight) * track_A.m_interval_start[i]
+          + weight * track_B.m_interval_start[i];
+
+      result.m_interval_end[i] =
+          (1.0f - weight) * track_A.m_interval_end[i]
+          + weight * track_B.m_interval_end[i];
+
+      result.m_sync_markers[i] =
+          (1.0f - weight) * track_A.m_sync_markers[i]
+          + weight * track_B.m_sync_markers[i];
     }
 
     return result;
   }
 };
 
-
 struct SkinnedMesh {
   virtual ~SkinnedMesh();
   bool LoadSkeleton(const char* filename);
@@ -61,8 +116,12 @@ struct SkinnedMesh {
   //bool LoadMesh (const char* filename);
 
   void SetCurrentAnimation(int index);
-  const ozz::animation::Animation* GetCurrentAnimation() {return m_current_animation; };
-  float GetCurrentAnimationDuration() {return m_current_animation->duration(); };
+  const ozz::animation::Animation* GetCurrentAnimation() {
+    return m_current_animation;
+  };
+  float GetCurrentAnimationDuration() {
+    return m_current_animation->duration();
+  };
 
   void EvalAnimation(float in_time);
   void DrawSkeleton();

tests/SyncTrackTests.cc

@@ -2,44 +2,154 @@
 // Created by martin on 16.11.21.
 //
 
+#include "SkinnedMesh.h"
 #include "catch.hpp"
 
-#include "SkinnedMesh.h"
-
-TEST_CASE("SyncTrackBlendSimple", "[SyncTrackBlend]") {
+TEST_CASE("Basic", "[SyncTrack]") {
   SyncTrack track_A;
   track_A.m_num_intervals = 2;
-  track_A.m_duration = 1.0;
-  track_A.m_interval_durations[0] = 0.8;
-  track_A.m_interval_durations[1] = 0.2;
+  track_A.m_duration = 2.0;
+  track_A.m_interval_start[0] = 0.f;
+  track_A.m_interval_end[0] = 0.7f;
+  track_A.m_interval_durations[0] = 0.7;
+  track_A.m_interval_start[1] = 0.7f;
+  track_A.m_interval_end[1] = 1.0f;
+  track_A.m_interval_durations[1] = 0.3;
 
   SyncTrack track_B;
   track_B.m_num_intervals = 2;
-  track_B.m_duration = 2.0;
-  track_B.m_interval_durations[0] = 0.1;
-  track_B.m_interval_durations[1] = 0.9;
+  track_B.m_duration = 1.5;
+  track_B.m_interval_start[0] = 0.0f;
+  track_B.m_interval_end[0] = 0.6f;
+  track_B.m_interval_durations[0] = 0.6;
+  track_B.m_interval_start[1] = 0.6f;
+  track_B.m_interval_end[1] = 1.0f;
+  track_B.m_interval_durations[1] = 0.4;
+
+  WHEN("Calculating sync time of track_B at 0.5 duration") {
+    float sync_time_at_0_75 =
+        track_B.CalcSyncFromAbsTime(0.5 * track_B.m_duration);
+    REQUIRE(sync_time_at_0_75 == Catch::Detail::Approx(0.83333));
+  }
+
+  WHEN("Calculating sync time of track_B at 0.6 duration") {
+    float sync_time_at_0_6 =
+        track_B.CalcSyncFromAbsTime(0.6 * track_B.m_duration);
+    REQUIRE(sync_time_at_0_6 == Catch::Detail::Approx(1.0));
+  }
+
+  WHEN("Calculating sync time of track_B at 0.7 duration") {
+    float sync_time_at_0_7 =
+        track_B.CalcSyncFromAbsTime(0.7 * track_B.m_duration);
+    REQUIRE(sync_time_at_0_7 == Catch::Detail::Approx(1.25));
+  }
+
+  WHEN("Calculating sync time of track_B at 0.0 duration") {
+    float sync_time_at_1_0 =
+        track_B.CalcSyncFromAbsTime(0.0 * track_B.m_duration);
+    REQUIRE(sync_time_at_1_0 == Catch::Detail::Approx(0.0));
+  }
+
+  WHEN("Calculating sync time of track_B at 1.0 duration") {
+    float sync_time_at_1_0 =
+        track_B.CalcSyncFromAbsTime(0.9999 * track_B.m_duration);
+    REQUIRE(sync_time_at_1_0 == Catch::Detail::Approx(2.0).epsilon(0.001f));
+  }
+
+  WHEN("Calculating ratio from sync time on track_A at 0.83333") {
+    float ratio = track_A.CalcRatioFromSyncTime(0.83333333);
+    REQUIRE(ratio == Catch::Detail::Approx(0.5833333));
+  }
+
+  WHEN("Calculating ratio from sync time on track_A at 0.83333") {
+    float ratio = track_A.CalcRatioFromSyncTime(1.25);
+    REQUIRE(ratio == Catch::Detail::Approx(0.775));
+  }
 
   WHEN("Blending two synctracks with weight 0.") {
     SyncTrack blended = SyncTrack::Blend(0.f, track_A, track_B);
 
-    THEN ("Result must equal track_A") {
+    THEN("Result must equal track_A") {
       REQUIRE(blended.m_duration == track_A.m_duration);
       REQUIRE(
           blended.m_interval_durations[0] == track_A.m_interval_durations[0]);
       REQUIRE(
           blended.m_interval_durations[1] == track_A.m_interval_durations[1]);
+      
+      REQUIRE(blended.m_sync_markers[0] == track_A.m_sync_markers[0]);
+      REQUIRE(blended.m_sync_markers[1] == track_A.m_sync_markers[1]);
+
+      REQUIRE(blended.m_interval_start[0] == track_A.m_interval_start[0]);
+      REQUIRE(blended.m_interval_start[1] == track_A.m_interval_start[1]);
+    
+      REQUIRE(blended.m_interval_end[0] == track_A.m_interval_end[0]);
+      REQUIRE(blended.m_interval_end[1] == track_A.m_interval_end[1]);
     }
   }
 
   WHEN("Blending two synctracks with weight 1.") {
     SyncTrack blended = SyncTrack::Blend(1.f, track_A, track_B);
 
-    THEN ("Result must equal track_B") {
+    THEN("Result must equal track_B") {
       REQUIRE(blended.m_duration == track_B.m_duration);
       REQUIRE(
           blended.m_interval_durations[0] == track_B.m_interval_durations[0]);
       REQUIRE(
           blended.m_interval_durations[1] == track_B.m_interval_durations[1]);
+      
+      REQUIRE(blended.m_sync_markers[0] == track_B.m_sync_markers[0]);
+      REQUIRE(blended.m_sync_markers[1] == track_B.m_sync_markers[1]);
+      
+      REQUIRE(blended.m_interval_start[0] == track_B.m_interval_start[0]);
+      REQUIRE(blended.m_interval_start[1] == track_B.m_interval_start[1]);
+    
+      REQUIRE(blended.m_interval_end[0] == track_B.m_interval_end[0]);
+      REQUIRE(blended.m_interval_end[1] == track_B.m_interval_end[1]);
     }
   }
 }
+
+
+
+TEST_CASE("Sync Marker Interval Calculation", "[SyncTrack]") {
+  SyncTrack track_A;
+  track_A.m_num_intervals = 2;
+  track_A.m_duration = 2.0;
+  track_A.m_sync_markers[0] = 0.9;
+  track_A.m_sync_markers[1] = 0.2;
+
+  WHEN("Calculating intervals") {
+    track_A.CalcIntervals();
+
+    CHECK(track_A.m_interval_start[0] == 0.9f);
+    CHECK(track_A.m_interval_end[0] == 0.2f);
+    CHECK(track_A.m_interval_durations[0] == 0.3f);
+
+    CHECK(track_A.m_interval_start[1] == 0.2f);
+    CHECK(track_A.m_interval_end[1] == 0.9f);
+    CHECK(track_A.m_interval_durations[1] == 0.7f);
+
+    WHEN("Querying ratio at sync time at 1.001") {
+      float ratio = track_A.CalcRatioFromSyncTime(1.0001f);
+      CHECK(ratio == Catch::Detail::Approx(0.2).epsilon(0.001));
+    }
+
+    WHEN("Querying ratio at sync time at 1.001") {
+      float ratio = track_A.CalcRatioFromSyncTime(0.0001f);
+      CHECK(ratio == Catch::Detail::Approx(0.9).epsilon(0.001));
+    }
+
+    WHEN("Querying ratio at sync time at 1.9999") {
+      float ratio = track_A.CalcRatioFromSyncTime(0.9999f);
+      CHECK(ratio == Catch::Detail::Approx(0.2).epsilon(0.001));
+    }
+  }
+
+  WHEN ("Blending with another sync track") {
+    SyncTrack track_B;
+    track_B.m_num_intervals = 2;
+    track_B.m_duration = 1.0;
+    track_B.m_sync_markers[0] = 0.9;
+    track_B.m_sync_markers[1] = 0.2;
+  }
+}