Tag: Mesh

I’m trying to animate a skeletal mesh. The mesh loads with no problems and all is set up correctly. My problem is that when I calculate the matrix for a given keyframe the mesh go nuts.

Here is na image of the problem.

The mesh on the right is using the boné transform as the final matrix. the ne one the left is using the matrix calculated from keyframes. I don’t know where i’m going wrong with this.

Here is my code:

The Animation Clip where all keyframes are stored:

Matrix4 AnimationClip::GetTransform(Bone *bone, float deltaTime) { Channel* channel = channels[bone->name]; if (channel == nullptr)     return bone->transform; else     return channel->Update(deltaTime); }  ///////////  Channel::Channel(aiNodeAnim* animNode) { name = string(animNode->mNodeName.data);  for (GLuint k = 0; k < animNode->mNumPositionKeys; k++) {     aiVectorKey vec = animNode->mPositionKeys[k];     positions.push_back(         Keyframe<Vector3>(         (float)vec.mTime,             Vector3(vec.mValue.x, vec.mValue.y, vec.mValue.z))); }  for (GLuint k = 0; k < animNode->mNumScalingKeys; k++) {     aiVectorKey vec = animNode->mScalingKeys[k];     scalings.push_back(         Keyframe<Vector3>(         (float)vec.mTime,             Vector3(vec.mValue.x, vec.mValue.y, vec.mValue.z))); }  for (GLuint k = 0; k < animNode->mNumRotationKeys; k++) {     aiQuatKey vec = animNode->mRotationKeys[k];     rotations.push_back(         Keyframe<Quaternion>(         (float)vec.mTime,             Quaternion(                 vec.mValue.x,                 vec.mValue.y,                 vec.mValue.z,                 vec.mValue.w))); } }  Matrix4 Channel::Update(float animTime) { return     CalculatePosition(animTime) *     CalculateRotation(animTime) *     CalculateScaling(animTime); }  Matrix4 Channel::CalculatePosition(float animationTime) { return      Matrix4::CreateTranslation(         CalcInterpolatedPosition(animationTime)); }  Vector3 Channel::CalcInterpolatedPosition(float animationTime) { if (positions.size() == 1)     return positions[0].value;  GLuint positionIndex = FindPosition(animationTime); GLuint nextPositionIndex = (positionIndex + 1);  float deltaTime =      positions[nextPositionIndex].time - positions[positionIndex].time; float factor =      (animationTime - (float)positions[positionIndex].time) / deltaTime;  Vector3 startPos = positions[positionIndex].value; Vector3 endPos = positions[nextPositionIndex].value;  Vector3 delta = endPos - startPos;  return startPos + delta * factor;//Vector3::Lerp(startPos, endPos, factor); }  GLuint Channel::FindPosition(float AnimationTime) { for (GLuint i = 0; i < positions.size() - 1; i++) {     if (AnimationTime < (float)positions[i + 1].time)         return i; } return 0; } 

And Here is my Skinned Mesh code where I’m fetching the keyframes:

void SkinnedMesh::BoneTransform( double delta,  vector<Matrix4>& transforms, AnimationClip *anim) { Matrix4 identity_matrix = Matrix4::Identity();  float ticksPerSecond =      anim->ticksPerSecond == 0 ? 25.0f : anim->ticksPerSecond;  double time_in_ticks = delta * ticksPerSecond; float animation_time =      fmod((float)time_in_ticks, anim->duration);  UpdateTransforms(     animation_time,      anim,      rootBone,     identity_matrix);  transforms.resize(m_num_bones);  for (GLuint i = 0; i < m_num_bones; i++)     transforms[i] =          m_bone_matrices[i].final_world_transform; }  void SkinnedMesh::UpdateTransforms( float p_animation_time, AnimationClip *anim, Bone *parentBone, Matrix4& parentTransform) { Matrix4 boneTransform =// parentBone->transform;     anim->GetTransform(parentBone, p_animation_time);  Matrix4 global_transform =     parentTransform * boneTransform;  if (m_bone_mapping.find(parentBone->name) !=     m_bone_mapping.end()) // true if node_name exist in bone_mapping {     GLuint bone_index = m_bone_mapping[parentBone->name];     m_bone_matrices[bone_index].final_world_transform =         m_global_inverse_transform *         global_transform *          m_bone_matrices[bone_index].offset_matrix; }  for (vector<Bone*>::iterator it =     parentBone->children.begin();     it != parentBone->children.end();      it++) {     UpdateTransforms(         p_animation_time,         anim,         (*it),          global_transform); } }  void SkinnedMesh::Render(Shader* shader, AnimationClip *clip) { vector<Matrix4> transforms; BoneTransform(     (double)SDL_GetTicks() / 1000.0f,     transforms,     clip);  for (GLuint i = 0; i < transforms.size(); i++) {     GLfloat values[16];     Matrix4::ValuePointer(transforms[i], values);      string a = "jointTransforms[";     a.append(to_string(i));     a.append("]");      glProgramUniformMatrix4fv(         shader->GetID(),         shader->GetUniformLocation(a.c_str()),         1,         GL_FALSE,          (const GLfloat*)values); }  for (unsigned int i = 0; i < meshes.size(); i++)     meshes[i]->Render(shader); } 

It seems the matrices are all wrong and therefore deforming the mesh. Can you help me?

EDIT :

The Meh on the right has this code :

Matrix4 AnimationClip::GetTransform(Bone *bone, float deltaTime) { Channel* channel = channels[bone->name]; if (channel == nullptr) return bone->transform; else return bone->transform; 

}