Implemented blend2 node.

src/AnimationController.cc

@@ -10,6 +10,7 @@
 #include <ozz/animation/runtime/sampling_job.h>
 
 #include "AnimSamplerNode.h"
+#include "BlendNode.h"
 #include "SkinnedMesh.h"
 #include "SpeedScaleNode.h"
 
@@ -26,17 +27,28 @@ AnimationController::AnimationController(SkinnedMesh* skinned_mesh)
   SetBlendAnims(skinned_mesh->m_animations[1], skinned_mesh->m_animations[0]);
   ResetAnims();
 
-  AnimSamplerNode* sampler_node = new AnimSamplerNode(this);
-  sampler_node->m_name = "AnimSampler0";
-  sampler_node->SetAnimation(skinned_mesh->m_animations[0]);
-  m_anim_nodes.push_back(sampler_node);
+  AnimSamplerNode* sampler_node0 = new AnimSamplerNode(this);
+  sampler_node0->m_name = "AnimSampler0";
+  sampler_node0->SetAnimation(skinned_mesh->m_animations[1]);
+  m_anim_nodes.push_back(sampler_node0);
+
+  AnimSamplerNode* sampler_node1 = new AnimSamplerNode(this);
+  sampler_node1->m_name = "AnimSampler0";
+  sampler_node1->SetAnimation(skinned_mesh->m_animations[2]);
+  m_anim_nodes.push_back(sampler_node1);
 
   SpeedScaleNode* speed_node = new SpeedScaleNode(this);
   speed_node->m_name = "SpeedNode0";
-  speed_node->m_child_node = sampler_node;
+  speed_node->m_input_node = sampler_node0;
   m_anim_nodes.push_back(speed_node);
 
-  m_output_node = speed_node;
+  BlendNode* blend_node = new BlendNode(this);
+  blend_node->m_name = "Blend0";
+  blend_node->m_input_A = speed_node;
+  blend_node->m_input_B = sampler_node1;
+  m_anim_nodes.push_back(blend_node);
+
+  m_output_node = blend_node;
   m_output_node->Reset();
 }
 

src/BlendNode.cc

@@ -0,0 +1,59 @@
+//
+// Created by martin on 12.11.21.
+//
+
+#include "BlendNode.h"
+
+#include <ozz/animation/runtime/blending_job.h>
+
+#include "SkinnedMesh.h"
+#include <imgui.h>
+
+BlendNode::BlendNode(AnimationController* animation_controller)
+    : AnimNode(animation_controller),
+      m_input_A(nullptr),
+      m_input_B(nullptr),
+      m_weight(0.f) {
+  const SkinnedMesh* skinned_mesh = m_animation_controller->m_skinned_mesh;
+  const int num_soa_joints = skinned_mesh->m_skeleton.num_soa_joints();
+  const int num_joints = skinned_mesh->m_skeleton.num_joints();
+  m_local_matrices_A.resize(num_soa_joints);
+  m_local_matrices_B.resize(num_soa_joints);
+}
+
+void BlendNode::Evaluate(ozz::vector<ozz::math::SoaTransform>* local_matrices) {
+  const SkinnedMesh* skinned_mesh = m_animation_controller->m_skinned_mesh;
+
+  m_input_A->Evaluate(&m_local_matrices_A);
+  m_input_B->Evaluate(&m_local_matrices_B);
+
+  // perform blend
+  ozz::animation::BlendingJob::Layer layers[2];
+  layers[0].transform = make_span(m_local_matrices_A);
+  layers[0].weight = (1.0f - m_weight);
+
+  layers[1].transform = make_span(m_local_matrices_B);
+  layers[1].weight = (m_weight);
+
+  ozz::animation::BlendingJob blend_job;
+  blend_job.threshold = ozz::animation::BlendingJob().threshold;
+  blend_job.layers = layers;
+  blend_job.bind_pose = skinned_mesh->m_skeleton.joint_bind_poses();
+  blend_job.output = make_span(*local_matrices);
+
+  if (!blend_job.Run()) {
+    ozz::log::Err() << "Error blending animations." << std::endl;
+  }
+}
+
+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::TreePop();
+  }
+}

src/BlendNode.h

@@ -0,0 +1,36 @@
+//
+// Created by martin on 12.11.21.
+//
+
+#ifndef ANIMTESTBED_BLENDNODE_H
+#define ANIMTESTBED_BLENDNODE_H
+
+#include "AnimNode.h"
+
+struct BlendNode : public AnimNode {
+  BlendNode(AnimationController* animation_controller);
+  virtual ~BlendNode() {}
+
+  AnimNode* m_input_A;
+  AnimNode* m_input_B;
+  float m_weight;
+
+  ozz::vector<ozz::math::SoaTransform> m_local_matrices_A;
+  ozz::vector<ozz::math::SoaTransform> m_local_matrices_B;
+
+  virtual void Reset() {
+    m_current_time = 0.f;
+  }
+
+  virtual void Update(float dt) {
+    m_input_A->Update(dt);
+    m_input_B->Update(dt);
+  }
+
+  virtual void Evaluate(
+      ozz::vector<ozz::math::SoaTransform>* local_matrices) override;
+
+  virtual void DrawDebugUi();
+};
+
+#endif  //ANIMTESTBED_BLENDNODE_H

src/SpeedScaleNode.cc

@@ -11,7 +11,7 @@ void SpeedScaleNode::DrawDebugUi() {
   if (ImGui::TreeNode(node_name.c_str())) {
     ImGui::SliderFloat("Time Scale", &m_time_scale, -5.f, 5.f);
 
-    m_child_node->DrawDebugUi();
+    m_input_node->DrawDebugUi();
 
     ImGui::TreePop();
   }

src/SpeedScaleNode.h

@@ -11,7 +11,7 @@ struct SpeedScaleNode : public AnimNode {
   SpeedScaleNode(AnimationController* animation_controller): AnimNode (animation_controller), m_time_scale(1.f) {}
 
   float m_time_scale;
-  AnimNode* m_child_node;
+  AnimNode* m_input_node;
 
   virtual void Reset() {
     m_current_time = 0.f;
@@ -19,11 +19,11 @@ struct SpeedScaleNode : public AnimNode {
 
   virtual void Update(float dt) {
     m_current_time += dt * m_time_scale;
-    m_child_node->Update(dt * m_time_scale);
+    m_input_node->Update(dt * m_time_scale);
   }
 
   virtual void Evaluate(ozz::vector<ozz::math::SoaTransform>* local_matrices) override {
-      m_child_node->Evaluate(local_matrices);
+    m_input_node->Evaluate(local_matrices);
   };
 
   virtual void DrawDebugUi() override;