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Refactor Newton's Cradle. Implement Newton's Cradle with Softbody ropes.

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This commit is contained in:
Benjamin Ellenberger
2016-06-27 15:14:36 +02:00
parent e46a718807
commit e16082a7cd
6 changed files with 385 additions and 19 deletions
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27
examples/ExtendedTutorials/NewtonsCradle.cpp
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@@ -30,7 +30,7 @@ static btScalar gPendulaQty = 5; // Number of pendula in newton's cradle
static btScalar gDisplacedPendula = 1; // number of displaced pendula
//TODO: This is an int as well
static btScalar gPendulaRestitution = 1; // pendula restition when hitting against each other
static btScalar gPendulaRestitution = 1; // pendula restitution when hitting against each other
static btScalar gSphereRadius = 1; // pendula radius
@@ -48,8 +48,7 @@ struct NewtonsCradleExample: public CommonRigidBodyBase {
}
virtual void initPhysics();
virtual void renderScene();
virtual void createPendulum(btSphereShape* colShape, btScalar xPosition,
btScalar yPosition, btScalar zPosition, btScalar length, btScalar mass);
virtual void createPendulum(btSphereShape* colShape, btVector3 position, btScalar length, btScalar mass);
virtual void changePendulaLength(btScalar length);
virtual void changePendulaRestitution(btScalar restitution);
virtual void stepSimulation(float deltaTime);
@@ -139,12 +138,11 @@ void NewtonsCradleExample::initPhysics() {
+ btIDebugDraw::DBG_DrawConstraints
+ btIDebugDraw::DBG_DrawConstraintLimits);
{ // create the pendulum starting at the indicated position below and where each pendulum has the following mass
{ // create the pendula starting at the indicated position below and where each pendulum has the following mass
btScalar pendulumMass(1.f);
btScalar xPosition(0.0f); // initial left-most pendulum position
btScalar yPosition(15.0f);
btScalar zPosition(0.0f);
btVector3 position(0.0f,15.0f,0.0f); // initial left-most pendulum position
btQuaternion orientation(0,0,0,1); // orientation of the pendula
// Re-using the same collision is better for memory usage and performance
btSphereShape* pendulumShape = new btSphereShape(gSphereRadius);
@@ -153,11 +151,10 @@ void NewtonsCradleExample::initPhysics() {
for (int i = 0; i < floor(gPendulaQty); i++) {
// create pendulum
createPendulum(pendulumShape, xPosition, yPosition, zPosition,
gInitialPendulumLength, pendulumMass);
createPendulum(pendulumShape, position, gInitialPendulumLength, pendulumMass);
// displace the pendula 1.05 sphere size, so that they all nearly touch (small spacings in between
xPosition -= 2.1f * gSphereRadius;
position.setX(position.x()-2.1f * gSphereRadius);
}
}
@@ -171,8 +168,7 @@ void NewtonsCradleExample::stepSimulation(float deltaTime) {
}
void NewtonsCradleExample::createPendulum(btSphereShape* colShape,
btScalar xPosition, btScalar yPosition, btScalar zPosition, btScalar length, btScalar mass) {
void NewtonsCradleExample::createPendulum(btSphereShape* colShape,btVector3 position, btScalar length, btScalar mass) {
// The pendulum looks like this (names when built):
// O topSphere
@@ -184,15 +180,14 @@ void NewtonsCradleExample::createPendulum(btSphereShape* colShape,
startTransform.setIdentity();
// position the top sphere above ground with a moving x position
startTransform.setOrigin(
btVector3(btScalar(xPosition), btScalar(yPosition), btScalar(zPosition)));
startTransform.setOrigin(position);
startTransform.setRotation(btQuaternion(0, 0, 0, 1)); // zero rotation
btRigidBody* topSphere = createRigidBody(mass, startTransform, colShape);
// position the bottom sphere below the top sphere
startTransform.setOrigin(
btVector3(btScalar(xPosition), btScalar(yPosition - length),
btScalar(zPosition)));
btVector3(position.x(), btScalar(position.y() - length),
position.z()));
startTransform.setRotation(btQuaternion(0, 0, 0, 1)); // zero rotation
btRigidBody* bottomSphere = createRigidBody(mass, startTransform, colShape);