faerbit/Saxum
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added a scaling factor to triangle meshes to compensate for diffrent scaling (somehow from bullet, idk) and started adding comments to physics.cc

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Jasper 2015-01-29 13:15:45 +01:00
parent e0d9058aef
commit 8620e16681
3 changed files with 66 additions and 150 deletions
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2
level.cc
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@ -275,7 +275,7 @@ void Level::load() {
errorCheck(objectData->FirstChildElement("length")->QueryFloatText(&length)); errorCheck(objectData->FirstChildElement("length")->QueryFloatText(&length));
this->physics.addButton(width, height, length, *object, mass, dampningL, dampningA, physicObjects.size(), rotate); this->physics.addButton(width, height, length, *object, mass, dampningL, dampningA, physicObjects.size(), rotate);
}else if (physicType.compare("TriangleMesh") == 0){ }else if (physicType.compare("TriangleMesh") == 0){
this->physics.addTriangleMeshBody(*object, modelPath, mass, dampningL, dampningA, physicObjects.size(), rotate); this->physics.addTriangleMeshBody(*object, modelPath, mass, dampningL, dampningA, physicObjects.size(),objectScale, rotate);
} else{ } else{
printf("XMLError: Not a valid physicType.\n"); printf("XMLError: Not a valid physicType.\n");
exit(-1); exit(-1);

211
physics.cc
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@ -8,7 +8,7 @@ Physics::Physics() {
Physics::~Physics() { Physics::~Physics() {
} }
void Physics::init() void Physics::init() //prepares bullet by creating all initial classes
{ {
colConfig = new btDefaultCollisionConfiguration(); colConfig = new btDefaultCollisionConfiguration();
dispatcher = new btCollisionDispatcher(colConfig); dispatcher = new btCollisionDispatcher(colConfig);
@ -20,39 +20,29 @@ void Physics::init()
void Physics::takeUpdateStep(float timeDiff) void Physics::takeUpdateStep(float timeDiff)
{ {
world->stepSimulation(timeDiff); world->stepSimulation(timeDiff); //allows the world to be simmulated correctly indipendant of the timedifferences between frames
for(unsigned i = 0; i < allPositionConstraints.size();i++) for(unsigned i = 0; i < allPositionConstraints.size();i++) //this handles the spring constraints
{ {
if(allPositionConstraints[i].position != allPositionConstraints[i].body->getCenterOfMassPosition()) if(allPositionConstraints[i].position != allPositionConstraints[i].body->getCenterOfMassPosition()) //if constraint != position of the body because otherwise dir = 0
{ {
btVector3 dir = allPositionConstraints[i].position - allPositionConstraints[i].body->getCenterOfMassPosition(); btVector3 dir = allPositionConstraints[i].position - allPositionConstraints[i].body->getCenterOfMassPosition();
allPositionConstraints[i].body->applyCentralForce(dir*allPositionConstraints[i].strength); allPositionConstraints[i].body->applyCentralForce(dir*allPositionConstraints[i].strength); //apply a foce upon the object pushing it towards the constraint position
} }
} }
btVector3 position = playerBall->getCenterOfMassPosition() ; btVector3 position = cameraBody->getCenterOfMassPosition() - playerBall->getCenterOfMassPosition(); //gets a vector from the player to the camera
position.normalize(); position.normalize();
position *=5; position *=5;
position += playerBall->getCenterOfMassPosition(); //is the position 5 units away from the player in the direction of the camera position += playerBall->getCenterOfMassPosition(); //is the position 5 units away from the player in the direction of the camera
btVector3 dir = cameraBody->getCenterOfMassPosition() - position; btVector3 dir = cameraBody->getCenterOfMassPosition() - position;
cameraBody->applyCentralForce(dir); cameraBody->applyCentralForce(dir*cameraBody->getInvMass());//scale the force by camera mass
cameraBody->applyCentralForce(btVector3(0,10,0)); cameraBody->applyCentralForce(btVector3(0,1,0)); //applies a force to the camera keeping it in a correct position
/*- cameraBody->getCenterOfMassPosition(); // gives vector from player to camera
position.normalize();
position *=5;
position += playerBall->getCenterOfMassPosition(); //is the position 5 units away from the player in the direction of the camera
btVector3 dir = cameraBody->getCenterOfMassPosition() - position;
cameraBody->applyCentralForce(dir);
*/
} }
void Physics::removePositionConstraint(int bodyIndice) void Physics::removePositionConstraint(int bodyIndice) //remover function for deleting all pos constraints on one body
{ {
for(unsigned i = 0; i < allPositionConstraints.size(); i++) for(unsigned i = 0; i < allPositionConstraints.size(); i++)
{ {
@ -63,7 +53,7 @@ void Physics::removePositionConstraint(int bodyIndice)
} }
} }
void Physics::addPositionConstraint(int bodyIndice, float strength, glm::vec3 position) void Physics::addPositionConstraint(int bodyIndice, float strength, glm::vec3 position) //function for adding position constraints
{ {
positionConstraint cons; positionConstraint cons;
cons.body = bodies[bodyIndice]; cons.body = bodies[bodyIndice];
@ -72,162 +62,119 @@ void Physics::addPositionConstraint(int bodyIndice, float strength, glm::vec3 po
allPositionConstraints.push_back(cons); allPositionConstraints.push_back(cons);
} }
//TERRAIN SUBSET //players and objects
void Physics::addTerrainTriangles(int width, int length, float** heightData) void Physics::addPlayer(float friction, float rad, Entity entity, float mass, float dampningL, float dampningA, unsigned indice)
{//not working correctly something with offset wrong? {
btTriangleMesh* trimesh = new btTriangleMesh(); if(bodies.size() == indice)
for(int i = 0; i < width-1;i++) throw std::invalid_argument( "Bodies out of Sync" ); //these error are to ensure that level can always communicate with physics without having to worry about synching errors
{
for(int j = 0; j < length-1; j++) btSphereShape* sphere = new btSphereShape(rad); //the first thing we need for a rigid body is the shape
{ btVector3 inertia(0,0,0);
btVector3 v0(i,heightData[j][i],j); if(mass != 0.0)
btVector3 v1(i+1,heightData[j][i+1],j); {
btVector3 v2(i,heightData[j+1][i],j+1); sphere->calculateLocalInertia((btScalar)mass,inertia); //from this shape we can then calculate the innertia, as long as the mass != 0 (otherwise inertia = 0)
}
trimesh->addTriangle(v0,v1,v2);
btDefaultMotionState* motion = new btDefaultMotionState(btTransform(btQuaternion(0,0,0,1),btVector3(entity.getPosition().x,entity.getPosition().y,entity.getPosition().z))); //next we define the motionstate, wich describes the innital position and rotation
}
} btRigidBody::btRigidBodyConstructionInfo info(mass,motion,sphere,inertia); //next we process all data for the rigid body into info
for(int i = 1; i < width;i++)
{ info.m_friction = friction*2; //here we modify the friction and restitution (bounciness) of the object
for(int j = 1; j < length; j++) info.m_restitution = 0.2f;
{
btVector3 v0(i,heightData[j][i],j); playerBall = new btRigidBody(info); //finally we create the rigid body using the info
btVector3 v1(i-1,heightData[j][i-1],j);
btVector3 v2(i,heightData[j-1][i],j-1);
trimesh->addTriangle(v0,v1,v2);
}
}
btBvhTriangleMeshShape* shape = new btBvhTriangleMeshShape(trimesh, true); playerBall->setDamping(dampningL, dampningA); //here we can set the dampning (how much of the motion is lost)
btRigidBody* tBody = new btRigidBody(0, new btDefaultMotionState(),shape);
tBody->getWorldTransform().setOrigin(btVector3(-length/2,0,-width/2)); world->addRigidBody(playerBall,COL_OBJECTS,COL_OBJECTS|COL_OBJECTS_NO_TERRAIN|COL_TERRAIN); //then we add the rigid body to the wiorld, allowing it to be simulated
terrainBody = tBody; bodies.push_back(playerBall); //next we add the rigid body to our own list (for cleanup and for synchronitaation with level)
world->addRigidBody(tBody,COL_TERRAIN,COL_OBJECTS);
playerBall->setSleepingThresholds(0,0); //in a final step we make sure that the body never is removed from the active rigid bodies
if(bodies.size() != indice)
throw std::invalid_argument( "Bodies out of Sync" ); //one last check to make sure level and physics are in synch
addCamera(); //now that the player exists add a camera for the player
} }
void Physics::addTerrain(int width, int length, float** heightData) void Physics::addTerrain(int width, int length, float** heightData) //The terrian adding function
{ {
float* heightfield = new float[width * length]; float* heightfield = new float[width * length];//bullet only accepts data in a one dimensional array, so parse data into appropriate format
int highest = -999999, j = 0, i = 0; int highest = -999999, j = 0, i = 0;
for (i = 0; i < width; i++) for (i = 0; i < width; i++)
{ {
for (j = 0; j < length; j++) { for (j = 0; j < length; j++) {
heightfield[i*length+j] = heightData[j][i]; heightfield[i*length+j] = heightData[j][i]; //reverse order because they are loaded backwards
if (heightData[j][i] > highest) if (heightData[j][i] > highest)
highest = heightData[j][i]; highest = heightData[j][i]; //bullet needs to know the highest point of the heightmap
} }
} }
highest++; highest++;
btHeightfieldTerrainShape* terrianShape = new btHeightfieldTerrainShape(length,width,heightfield,highest,1,true,false); btHeightfieldTerrainShape* terrianShape = new btHeightfieldTerrainShape(length,width,heightfield,highest,1,true,false);
btRigidBody* tBody = new btRigidBody(0,new btDefaultMotionState(),terrianShape); btRigidBody* tBody = new btRigidBody(0,new btDefaultMotionState(),terrianShape);
tBody->getWorldTransform().setOrigin(btVector3(0,((float)highest)/2,0)); tBody->getWorldTransform().setOrigin(btVector3(0,((float)highest)/2,0)); //we have to move the origin of our rigid body down, because bullet sets the origin (0,0,0) at (width/2, height/2, length/2) in the map the x and z are correct in our level, but y needs to be addapted
//tBody->getWoorldTransform().setRotation(btQuaternion(0,0,0,1));
terrainBody = tBody; terrainBody = tBody;
world->addRigidBody(terrainBody, COL_TERRAIN, COL_TERRAIN | COL_OBJECTS); world->addRigidBody(terrainBody, COL_TERRAIN, COL_TERRAIN | COL_OBJECTS); //COL_XXXX are collision masks, allowing us to ignore collisions between certain object groups (required for buttons)
} }
//players and objects void Physics::addTriangleMeshBody(Entity entity, std::string path, float mass, float dampningL, float dampningA,unsigned indice,float scaling, bool rotate)
void Physics::addPlayer(float friction, float rad, Entity entity, float mass, float dampningL, float dampningA, unsigned indice)
{ {
if(bodies.size() == indice)
throw std::invalid_argument( "Bodies out of Sync" );
btSphereShape* sphere = new btSphereShape(rad/1.5f);
btVector3 inertia(0,0,0);
if(mass != 0.0)
{
sphere->calculateLocalInertia((btScalar)mass,inertia);
}
btDefaultMotionState* motion = new btDefaultMotionState(btTransform(btQuaternion(0,0,0,1),btVector3(entity.getPosition().x,entity.getPosition().y,entity.getPosition().z)));
btRigidBody::btRigidBodyConstructionInfo info(mass,motion,sphere,inertia);
info.m_friction = friction*2;
info.m_restitution = 0.0f;
playerBall = new btRigidBody(info);
playerBall->setDamping(dampningL, dampningA);
world->addRigidBody(playerBall,COL_OBJECTS,COL_OBJECTS|COL_OBJECTS_NO_TERRAIN|COL_TERRAIN);
bodies.push_back(playerBall);
playerBall->setSleepingThresholds(0,0);
if(bodies.size() != indice)
throw std::invalid_argument( "Bodies out of Sync" );
addCamera();
}
void Physics::addTriangleMeshBody(Entity entity, std::string path, float mass, float dampningL, float dampningA,unsigned indice,bool rotate)
{//TODO look at convexHullShapes
if(bodies.size() == indice) if(bodies.size() == indice)
throw std::invalid_argument( "Bodies out of Sync" ); throw std::invalid_argument( "Bodies out of Sync" );
std::vector< unsigned int > vertexIndices; std::vector< unsigned int > vertexIndices; //temp lists for data sets
std::vector< btVector3 > temp_vertices; std::vector< btVector3 > temp_vertices;
path = "../Levels/Geometry/" + path; path = "../Levels/Geometry/" + path;
FILE * file = fopen(path.c_str(), "r"); FILE * file = fopen(path.c_str(), "r");
if( file == NULL ){ if( file == NULL ){
printf("Impossible to open the file !\n"); throw std::invalid_argument( "Impossible to open the file" ); //create correct filepath and report error if cannot open
} }
while( 1 ){ while( 1 ){
char lineHeader[128]; char lineHeader[128];
// read the first word of the line // read the first word of the line
int res = fscanf(file, "%s", lineHeader); int res = fscanf(file, "%s", lineHeader);
if (res == EOF) if (res == EOF)
break; // EOF = End Of File. Quit the loop. break; // while not at end do loop
// else : parse lineHeader if ( strcmp( lineHeader, "v" ) == 0 ){ //if a vertex
if ( strcmp( lineHeader, "v" ) == 0 ){
glm::vec3 vertex; glm::vec3 vertex;
fscanf(file, "%f %f %f\n", &vertex.x, &vertex.y, &vertex.z ); fscanf(file, "%f %f %f\n", &vertex.x, &vertex.y, &vertex.z );
temp_vertices.push_back(btVector3(vertex.x,vertex.y,vertex.z)); temp_vertices.push_back(btVector3(vertex.x,vertex.y,vertex.z)); //save vertex in array
} }
else if ( strcmp( lineHeader, "f" ) == 0 ){ else if ( strcmp( lineHeader, "f" ) == 0 ){ //if face (index for 3 vertexes for a triangle)
std::string vertex1, vertex2, vertex3; std::string vertex1, vertex2, vertex3;
unsigned int vertexIndex[3], uvIndex[3], normalIndex[3]; unsigned int vertexIndex[3], uvIndex[3], normalIndex[3];
int matches = fscanf(file, "%d/%d/%d %d/%d/%d %d/%d/%d\n", &vertexIndex[0], &uvIndex[0], &normalIndex[0], &vertexIndex[1], &uvIndex[1], &normalIndex[1], &vertexIndex[2], &uvIndex[2], &normalIndex[2] ); int matches = fscanf(file, "%d/%d/%d %d/%d/%d %d/%d/%d\n", &vertexIndex[0], &uvIndex[0], &normalIndex[0], &vertexIndex[1], &uvIndex[1], &normalIndex[1], &vertexIndex[2], &uvIndex[2], &normalIndex[2] );
vertexIndices.push_back(vertexIndex[0]); vertexIndices.push_back(vertexIndex[0]);
vertexIndices.push_back(vertexIndex[1]); vertexIndices.push_back(vertexIndex[1]);
vertexIndices.push_back(vertexIndex[2]); vertexIndices.push_back(vertexIndex[2]); //save 3 indexes in array
} }
} }
printf("olla");
//finally start making body //finally start making body
btTriangleMesh* triMesh = new btTriangleMesh(); btTriangleMesh* triMesh = new btTriangleMesh();
for(unsigned i = 2; i < vertexIndices.size();i+=3) for(unsigned i = 2; i < vertexIndices.size();i+=3)
{ {
triMesh->addTriangle(temp_vertices[vertexIndices[i]],temp_vertices[vertexIndices[i-1]],temp_vertices[vertexIndices[i-2]]); triMesh->addTriangle(temp_vertices[vertexIndices[i]],temp_vertices[vertexIndices[i-1]],temp_vertices[vertexIndices[i-2]]); // for every face (3 elements in vertexIndices) create triangle
} }
btBvhTriangleMeshShape* shape = new btBvhTriangleMeshShape(triMesh,true); btBvhTriangleMeshShape* shape = new btBvhTriangleMeshShape(triMesh,true);
shape->setLocalScaling(btVector3(1.5,1.5,1.5)); shape->setLocalScaling(btVector3(scaling,scaling,scaling)); //we need to add a scaling here because the objects seem to have diffrent sizes when loaded (no clue why, see composition.xml for exact scaling factors)
btDefaultMotionState* motion = new btDefaultMotionState(btTransform(btQuaternion(0,0,0,1),btVector3(entity.getPosition().x,entity.getPosition().y,entity.getPosition().z))); btDefaultMotionState* motion = new btDefaultMotionState(btTransform(btQuaternion(0,0,0,1),btVector3(entity.getPosition().x,entity.getPosition().y,entity.getPosition().z)));
btVector3 inertia(0,0,0); btVector3 inertia(0,0,0);
if(mass != 0.0) if(mass != 0.0 && rotate) //&& rotate lets certain objects get inertia (0,0,0) (not rotateable)
{ {
shape->calculateLocalInertia((btScalar)mass,inertia); shape->calculateLocalInertia((btScalar)mass,inertia);
} }
@ -257,11 +204,7 @@ void Physics::addButton(float width, float height, float length, Entity entity,
btDefaultMotionState* motion = new btDefaultMotionState(btTransform(btQuaternion(0,0,0,1),btVector3(entity.getPosition().x,entity.getPosition().y,entity.getPosition().z))); btDefaultMotionState* motion = new btDefaultMotionState(btTransform(btQuaternion(0,0,0,1),btVector3(entity.getPosition().x,entity.getPosition().y,entity.getPosition().z)));
btVector3 inertia(0,0,0); btVector3 inertia(0,0,0);
if(mass != 0.0)
{
box->calculateLocalInertia((btScalar)mass,inertia);
}
btRigidBody::btRigidBodyConstructionInfo info(mass,motion,box,inertia); btRigidBody::btRigidBodyConstructionInfo info(mass,motion,box,inertia);
@ -338,33 +281,6 @@ void Physics::addSphere(float rad, Entity entity, float mass, float dampningL, f
throw std::invalid_argument( "Bodies out of Sync" ); throw std::invalid_argument( "Bodies out of Sync" );
} }
/*
void Physics::addTriangleMeshBody(Entity entity, float mass, float dampningL, float dampningA,unsigned indice)
{
btTriangleMesh* trimesh = new btTriangleMesh();
btVector3 v0( 0, 0, 0 );
btVector3 v1( 1, 1, 1 );
btVector3 v2( 2, 2, 2);
trimesh->addTriangle( v0, v1, v2 );
btTriangleMeshShape* shape = new btBvhTriangleMeshShape(trimesh,true);
btVector3 inertia(0,0,0);
if(mass != 0.0)
{
shape->calculateLocalInertia((btScalar)mass,inertia);
}
btDefaultMotionState* motion = new btDefaultMotionState(btTransform(btQuaternion(0,0,0,1),btVector3(entity.getPosition().x,entity.getPosition().y,entity.getPosition().z)));
btRigidBody::btRigidBodyConstructionInfo info(mass,motion,shape,inertia);
btRigidBody* body = new btRigidBody(info);
body->setDamping(dampningL,dampningA);
}*/
void Physics::addCamera() void Physics::addCamera()
{ {
@ -382,7 +298,8 @@ void Physics::addCamera()
world->addRigidBody(cameraBody,COL_OBJECTS, objectsPhysicsCollision); world->addRigidBody(cameraBody,COL_OBJECTS, objectsPhysicsCollision);
cameraBody->setSleepingThresholds(0,0); cameraBody->setSleepingThresholds(0,0);
cameraBody->setGravity(btVector3(0,0,0));
/*btVector3 pivotInA(5,0,0); /*btVector3 pivotInA(5,0,0);
btVector3 pivotInB(-5, 0, 0); btVector3 pivotInB(-5, 0, 0);

3
physics.hh
View File

@ -58,9 +58,8 @@ class Physics {
void updateCameraPos(glm::vec2 mouseMovement, float strength); void updateCameraPos(glm::vec2 mouseMovement, float strength);
glm::vec3 getCameraPosition(); glm::vec3 getCameraPosition();
void addRigidBodyFromFile(Entity entity, float mass, float dampningL, float dampningA, std::string modelLocation, unsigned indice); void addRigidBodyFromFile(Entity entity, float mass, float dampningL, float dampningA, std::string modelLocation, unsigned indice);
void addTriangleMeshBody(Entity entity, std::string path, float mass, float dampningL, float dampningA, unsigned indice,bool rotate); void addTriangleMeshBody(Entity entity, std::string path, float mass, float dampningL, float dampningA, unsigned indice, float scaling,bool rotate);
void addTerrain(int width, int length, float** heightData); void addTerrain(int width, int length, float** heightData);
void addTerrainTriangles(int width, int length, float** heightData); //add the terrain as a trimesh instead of a heightmap
void addPlayer(float friction, float rad, Entity entity, float mass, float dampningL, float dampningA, unsigned indice); //use these AFTER physicObjects.push_back(object)! if mass == 0 then the object is unmoveable void addPlayer(float friction, float rad, Entity entity, float mass, float dampningL, float dampningA, unsigned indice); //use these AFTER physicObjects.push_back(object)! if mass == 0 then the object is unmoveable
void addSphere(float rad, Entity entity, float mass, float dampningL, float dampningA, unsigned indice,bool rotate); //The Indice should be set to physicObjects.size() void addSphere(float rad, Entity entity, float mass, float dampningL, float dampningA, unsigned indice,bool rotate); //The Indice should be set to physicObjects.size()
void addBox(float width, float height, float length, Entity entity, float mass, float dampningL, float dampningA, unsigned indice,bool rotate); //this is used to ensuer that the system is synchronized void addBox(float width, float height, float length, Entity entity, float mass, float dampningL, float dampningA, unsigned indice,bool rotate); //this is used to ensuer that the system is synchronized