Improvements in the Assimp importer (#41)

* remove hardcoded root node name

* change importer to process bones apart from mesh

* improvements in the assimp loader

* fix code style

* remove unused code

* remove unused param

* cleanup unecessary code

* removed boneNodes

* improve readability in bone hierarchy processing

* extract material processor

* remove empty line

* Update deploy.yml

* AnimationProcessor

* fix test

* fix tests

* fix test

* fix test

* fix test

* fix test

* fix test

* fix test

* fix test

* fix test

* fix test

* fix test

* fix test

* fix test

* fix test

* fix test

* fix tests

* Update deploy.yml

* Simplified importer code,
and allow loading textures from embedded files

* improve material processor code

* extracts the bone processor

* extract meshprocessor

* add unit test to bone processor

* Include the mesh processor test

* fix after cpp check insight

* improve based on cpp check

src/Assimp/AnimationProcessor.cpp

@@ -0,0 +1,89 @@
+#include "AnimationProcessor.h"
+
+AnimationProcessor::AnimationProcessor(Ogre::SkeletonPtr skeleton): skeleton(skeleton) {}
+
+void AnimationProcessor::processAnimations(const aiScene* scene) {
+    for(auto i = 0u; i < scene->mNumAnimations; i++) {
+        aiAnimation* animation = scene->mAnimations[i];
+        processAnimation(animation, scene);
+    }
+}
+
+void AnimationProcessor::processAnimation(aiAnimation* animation, const aiScene* scene) {
+    // Create the animation
+    Ogre::Animation* ogreAnimation = skeleton->createAnimation(animation->mName.C_Str(), animation->mDuration/10.0f);
+    // Process the animation channels
+    for(auto i = 0u; i < animation->mNumChannels; i++) {
+        aiNodeAnim* nodeAnim = animation->mChannels[i];
+        processAnimationChannel(nodeAnim, ogreAnimation, scene, i);
+    }
+}
+
+
+void AnimationProcessor::processAnimationChannel(aiNodeAnim* nodeAnim, Ogre::Animation* animation, const aiScene* scene, unsigned int channelIndex) {
+    // Create the animation track
+    Ogre::Bone* bone = skeleton->getBone(nodeAnim->mNodeName.C_Str());
+    Ogre::NodeAnimationTrack* track = animation->createNodeTrack(bone->getHandle(), bone);
+
+    // Create a map to store keyframes by time
+    std::map<double, std::tuple<Ogre::Vector3, Ogre::Quaternion, Ogre::Vector3>> keyframes;
+
+    // Process the position keys
+    for(auto i = 0u; i < nodeAnim->mNumPositionKeys; i++) {
+        aiVectorKey positionKey = nodeAnim->mPositionKeys[i];
+        Ogre::Vector3 position(positionKey.mValue.x, positionKey.mValue.y, positionKey.mValue.z);
+
+        // Get the bone's T-pose position
+        auto boneTPosePosition = bone->getPosition();
+
+        // Convert the position from local space to model space
+        position = position - boneTPosePosition;
+
+        keyframes[positionKey.mTime] = std::make_tuple(
+            position,
+            Ogre::Quaternion::IDENTITY,
+            Ogre::Vector3::UNIT_SCALE
+            );
+    }
+
+    // Process the rotation keys
+    for(auto i = 0u; i < nodeAnim->mNumRotationKeys; i++) {
+        aiQuatKey rotationKey = nodeAnim->mRotationKeys[i];
+        Ogre::Quaternion boneTPoseRotation = bone->getOrientation();
+        Ogre::Quaternion rot(rotationKey.mValue.w, rotationKey.mValue.x, rotationKey.mValue.y, rotationKey.mValue.z);
+        rot = boneTPoseRotation.Inverse() * rot; // Convert from local space to model space
+        rot.normalise(); // Normalize the quaternion
+        if (keyframes.find(rotationKey.mTime) == keyframes.end()) {
+            keyframes[rotationKey.mTime] = std::make_tuple(
+                Ogre::Vector3::ZERO,
+                rot,
+                Ogre::Vector3::UNIT_SCALE
+                );
+        } else {
+            std::get<1>(keyframes[rotationKey.mTime]) = rot;
+        }
+    }
+
+    // Process the scaling keys
+    for(auto i = 0u; i < nodeAnim->mNumScalingKeys; i++) {
+        aiVectorKey scalingKey = nodeAnim->mScalingKeys[i];
+        Ogre::Vector3 scale(scalingKey.mValue.x, scalingKey.mValue.y, scalingKey.mValue.z);
+        if (keyframes.find(scalingKey.mTime) == keyframes.end()) {
+            keyframes[scalingKey.mTime] = std::make_tuple(
+                Ogre::Vector3::ZERO,
+                Ogre::Quaternion::IDENTITY,
+                scale
+                );
+        } else {
+            std::get<2>(keyframes[scalingKey.mTime]) = scale;
+        }
+    }
+
+    // Now create the keyframes in the track
+    for(auto& [time, transform] : keyframes) {
+        Ogre::TransformKeyFrame* keyFrame = track->createNodeKeyFrame(time/10.0f);
+        keyFrame->setTranslate(std::get<0>(transform));
+        keyFrame->setRotation(std::get<1>(transform));
+        keyFrame->setScale(std::get<2>(transform));
+    }
+}

src/Assimp/AnimationProcessor.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include <Ogre.h>
+#include <assimp/scene.h>
+
+class AnimationProcessor
+{
+public:
+    AnimationProcessor(Ogre::SkeletonPtr skeleton);
+    void processAnimations(const aiScene* scene);
+
+private:
+    void processAnimation(aiAnimation* animation, const aiScene* scene);
+    void processAnimationChannel(aiNodeAnim* nodeAnim, Ogre::Animation* animation, const aiScene* scene, unsigned int channelIndex);
+    Ogre::SkeletonPtr skeleton;
+};
+

src/Assimp/AnimationProcessor_test.cpp

@@ -0,0 +1,26 @@
+#include <gtest/gtest.h>
+#include <gmock/gmock.h>
+#include "AnimationProcessor.h"
+
+// Test if processAnimations processes all animations
+TEST(AnimationProcessorTest, ProcessAllAnimations) {
+    auto ogreRoot = std::make_unique<Ogre::Root>();
+    auto mockSkeleton= Ogre::SkeletonManager::getSingleton().create("MockSkeleton",Ogre::ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME, true);
+    AnimationProcessor processor(mockSkeleton);
+
+    aiScene scene;
+    scene.mNumAnimations = 2;
+    scene.mAnimations = new aiAnimation*[2];
+    scene.mAnimations[0] = new aiAnimation;
+    scene.mAnimations[1] = new aiAnimation;
+    scene.mAnimations[0]->mName = aiString( std::string( "Animation1"));
+    scene.mAnimations[1]->mName = aiString( std::string( "Animation2"));
+    scene.mAnimations[0]->mNumChannels=0;
+    scene.mAnimations[1]->mNumChannels=0;
+
+    processor.processAnimations(&scene);
+
+    EXPECT_EQ(mockSkeleton->getNumAnimations(), 2);
+    EXPECT_EQ(mockSkeleton->getAnimation(0)->getName(), "Animation1");
+    EXPECT_EQ(mockSkeleton->getAnimation(1)->getName(), "Animation2");
+}

src/Assimp/BoneProcessor.cpp

@@ -0,0 +1,110 @@
+#include "BoneProcessor.h"
+
+void BoneProcessor::processBoneHierarchy(aiBone* bone) {
+    // Process the bone node
+    processBoneNode(bone);
+
+    // Recursively process children bones
+    for(auto i = 0u; i < bone->mNode->mNumChildren; i++) {
+        aiNode* childNode = bone->mNode->mChildren[i];
+        if(aiBonesMap.find(childNode->mName.C_Str()) != aiBonesMap.end()) {
+            processBoneHierarchy(aiBonesMap[childNode->mName.C_Str()]);
+        }
+    }
+}
+
+void BoneProcessor::processBones(Ogre::SkeletonPtr skeleton, const aiScene *scene) {
+    this->skeleton = skeleton;
+    for(auto i = 0u; i < scene->mNumMeshes; i++) {
+        aiMesh* mesh = scene->mMeshes[i];
+        for(auto j = 0u; j < mesh->mNumBones; j++) {
+            aiBone* bone = mesh->mBones[j];
+            // Check if the bone already exists
+            if(!skeleton->hasBone(bone->mName.C_Str())) {
+                aiBonesMap[bone->mName.C_Str()] = bone;
+                createBone(bone->mName.C_Str());
+            }
+        }
+    }
+
+    // Some models have bone animations but not all the bones are related to the meshes
+    for(auto i = 0u; i < scene->mNumAnimations; i++) {
+        aiAnimation* anim = scene->mAnimations[i];
+        for(auto j = 0u; j < anim->mNumChannels; j++) {
+            aiNodeAnim* nodeAnim = anim->mChannels[j];
+            createBone(nodeAnim->mNodeName.C_Str());
+        }
+    }
+
+    // Process the root bones first
+    for(auto i = 0u; i < scene->mNumMeshes; i++) {
+        aiMesh* mesh = scene->mMeshes[i];
+        for(auto j = 0u; j < mesh->mNumBones; j++) {
+            aiBone* bone = mesh->mBones[j];
+            if(bone->mNode && bone->mNode->mParent && !skeleton->hasBone(bone->mNode->mParent->mName.C_Str())) {
+                createBone(bone->mNode->mParent->mName.C_Str());
+                processBoneHierarchy(bone);
+            }
+        }
+    }
+}
+
+void BoneProcessor::createBone(const std::string& boneName) {
+    // Check if the bone already exists
+    if(!skeleton->hasBone(boneName)) {
+        // If the bone does not exist, create it
+        skeleton->createBone(boneName);
+    }
+}
+
+void BoneProcessor::processBoneNode(aiBone* bone) {
+    // Convert the aiBone's offset matrix to an Ogre::Matrix4
+    Ogre::Matrix4 offsetMatrix(
+        bone->mOffsetMatrix.a1, bone->mOffsetMatrix.a2, bone->mOffsetMatrix.a3, bone->mOffsetMatrix.a4,
+        bone->mOffsetMatrix.b1, bone->mOffsetMatrix.b2, bone->mOffsetMatrix.b3, bone->mOffsetMatrix.b4,
+        bone->mOffsetMatrix.c1, bone->mOffsetMatrix.c2, bone->mOffsetMatrix.c3, bone->mOffsetMatrix.c4,
+        bone->mOffsetMatrix.d1, bone->mOffsetMatrix.d2, bone->mOffsetMatrix.d3, bone->mOffsetMatrix.d4
+        );
+
+    // Invert the offset matrix to get the global transformation of the bone
+    Ogre::Matrix4 globalTransform = offsetMatrix.inverse();
+
+    // If the bone has a parent, multiply the global transformation of the bone with the inverse of the global transformation of the parent to get the local transformation
+    if(bone->mNode->mParent && bone->mNode->mParent->mName.length) {
+        Ogre::Bone* parentBone = skeleton->getBone(bone->mNode->mParent->mName.C_Str());
+        if(parentBone) {
+            Ogre::Matrix4 parentGlobalTransform = parentBone->_getFullTransform().inverse();
+            globalTransform = parentGlobalTransform * globalTransform;
+        }
+    }
+
+    // Convert the Ogre::Matrix4 to an Ogre::Affine3
+    Ogre::Affine3 affine(globalTransform);
+
+    // Decompose the offset matrix into position, scale, and orientation
+    Ogre::Vector3 position, scale;
+    Ogre::Quaternion orientation;
+    affine.decomposition(position, scale, orientation);
+
+    // Retrieve the bone (it should already exist)
+    Ogre::Bone* ogreBone = skeleton->getBone(bone->mName.C_Str());
+
+    // Set the bone's position, orientation, and scale
+    ogreBone->setPosition(position);
+    ogreBone->setOrientation(orientation);
+    ogreBone->setScale(scale);
+
+    // Add the bone to the parent bone, if it exists
+    if(bone->mNode->mParent && bone->mNode->mParent->mName.length) {
+        Ogre::Bone* parentBone = skeleton->getBone(bone->mNode->mParent->mName.C_Str());
+        if(parentBone) {
+            // Check if ogreBone is already a child of parentBone
+            if (!std::any_of(parentBone->getChildren().begin(), parentBone->getChildren().end(),
+                             [&ogreBone](const auto& childNode) {
+                                 return childNode->getName() == ogreBone->getName();
+                             })) {
+                parentBone->addChild(ogreBone);
+            }
+        }
+    }
+}

src/Assimp/BoneProcessor.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include <Ogre.h>
+#include <assimp/scene.h>
+
+class BoneProcessor {
+    public:
+        void processBones(Ogre::SkeletonPtr skeleton, const aiScene* scene);
+
+    private:
+        void createBone(const std::string& boneName);
+        void processBoneHierarchy(aiBone* bone);
+        void processBoneNode(aiBone *bone);
+
+        Ogre::SkeletonPtr skeleton;    
+        std::map<std::string, aiBone*> aiBonesMap;
+};