void NaiveRotationAlgorithm::stepSystem(SystemInfo *individual)
{
MachineSystem *oldSystem = individual->system;
individual->system = new MachineSystem(*oldSystem); // copy it to stop all the damn bouncing about
delete oldSystem;
cpBody *inputBody = individual->system->partAtPosition(individual->system->inputMachinePosition)->body;
cpBody *outputBody = individual->system->partAtPosition(individual->system->outputMachinePosition)->body;
cpSpace *systemSpace = individual->system->getSpace();
cpConstraint *motor = cpSimpleMotorNew(cpSpaceGetStaticBody(systemSpace), inputBody, M_PI);
cpSpaceAddConstraint(systemSpace, motor);
cpConstraintSetMaxForce(motor, 50000);
for (int i=0; i<simSteps; i++) {
individual->inputValues[i] = (cpBodyGetAngle(inputBody));
cpSpaceStep(systemSpace, 0.1);
individual->outputValues[i] = (cpBodyGetAngle(outputBody));
}
cpSpaceRemoveConstraint(systemSpace, motor);
cpBodySetAngVel(outputBody, 0);
cpBodySetAngle(inputBody, 0);
}
static void
update(int ticks)
{
cpFloat coef = (2.0f + ChipmunkDemoKeyboard.y)/3.0f;
cpFloat rate = ChipmunkDemoKeyboard.x*30.0f*coef;
cpSimpleMotorSetRate(motor, rate);
cpConstraintSetMaxForce(motor, rate ? 1000000.0f : 0.0f);
int steps = 2;
cpFloat dt = 1.0f/60.0f/(cpFloat)steps;
for(int i=0; i<steps; i++){
cpSpaceStep(space, dt);
for(int i=0; i<numBalls; i++){
cpBody *ball = balls[i];
cpVect pos = cpBodyGetPos(ball);
if(pos.x > 320.0f){
cpBodySetVel(ball, cpvzero);
cpBodySetPos(ball, cpv(-224.0f, 200.0f));
}
}
}
}
static void
update(cpSpace *space, double dt)
{
cpFloat coef = (2.0f + ChipmunkDemoKeyboard.y)/3.0f;
cpFloat rate = ChipmunkDemoKeyboard.x*10.0f*coef;
cpSimpleMotorSetRate(motor, rate);
cpConstraintSetMaxForce(motor, (rate) ? 100000.0f : 0.0f);
cpSpaceStep(space, dt);
}
/*
* Chipmunk2d::Constraint#max_force=(max_force)
* @param [Float] max_force
*/
static mrb_value
constraint_set_max_force(mrb_state *mrb, mrb_value self)
{
cpConstraint *constraint;
mrb_float max_force;
mrb_get_args(mrb, "f", &max_force);
constraint = mrb_data_get_ptr(mrb, self, &mrb_cp_constraint_type);
cpConstraintSetMaxForce(constraint, (cpFloat)max_force);
return mrb_nil_value();
}
static cpBool
StickyPreSolve(cpArbiter *arb, cpSpace *space, void *data)
{
// We want to fudge the collisions a bit to allow shapes to overlap more.
// This simulates their squishy sticky surface, and more importantly
// keeps them from separating and destroying the joint.
// Track the deepest collision point and use that to determine if a rigid collision should occur.
cpFloat deepest = INFINITY;
// Grab the contact set and iterate over them.
cpContactPointSet contacts = cpArbiterGetContactPointSet(arb);
for(int i=0; i<contacts.count; i++){
// Increase the distance (negative means overlaping) of the
// collision to allow them to overlap more.
// This value is used only for fixing the positions of overlapping shapes.
cpFloat dist = contacts.points[i].dist + 2.0f*STICK_SENSOR_THICKNESS;
contacts.points[i].dist = cpfmin(0.0f, dist);
deepest = cpfmin(deepest, dist);
}
// Set the new contact point data.
cpArbiterSetContactPointSet(arb, &contacts);
// If the shapes are overlapping enough, then create a
// joint that sticks them together at the first contact point.
if(!cpArbiterGetUserData(arb) && deepest <= 0.0f){
CP_ARBITER_GET_BODIES(arb, bodyA, bodyB);
// Create a joint at the contact point to hold the body in place.
cpConstraint *joint = cpPivotJointNew(bodyA, bodyB, contacts.points[0].point);
// Give it a finite force for the stickyness.
cpConstraintSetMaxForce(joint, 3e3);
// Schedule a post-step() callback to add the joint.
cpSpaceAddPostStepCallback(space, PostStepAddJoint, joint, NULL);
// Store the joint on the arbiter so we can remove it later.
cpArbiterSetUserData(arb, joint);
}
// Position correction and velocity are handled separately so changing
// the overlap distance alone won't prevent the collision from occuring.
// Explicitly the collision for this frame if the shapes don't overlap using the new distance.
return (deepest <= 0.0f);
// Lots more that you could improve upon here as well:
// * Modify the joint over time to make it plastic.
// * Modify the joint in the post-step to make it conditionally plastic (like clay).
// * Track a joint for the deepest contact point instead of the first.
// * Track a joint for each contact point. (more complicated since you only get one data pointer).
}
void physics_add_top_down_friction(cpBody *body, cpBody *control, float friction, cpConstraint **out_pivot, cpConstraint **out_gear) {
//emulates linear friction
cpConstraint *pivot = cpSpaceAddConstraint(game.space, cpPivotJointNew2(
control,
body,
cpvzero,
cpvzero
));
cpConstraintSetErrorBias(pivot, cpBodyGetMass(body) * friction);
cpConstraintSetMaxForce(pivot, cpBodyGetMass(body) * friction);
//emulates angular friction
cpConstraint *gear = cpSpaceAddConstraint(game.space, cpGearJointNew(
control,
body,
0, 1
));
cpConstraintSetMaxBias(gear, 0);
cpConstraintSetMaxForce(gear, friction / cpBodyGetMass(body) / 10);
if (out_pivot) *out_pivot = pivot;
if (out_gear) *out_gear = gear;
}
static void
update(int ticks)
{
cpFloat coef = (2.0f + ChipmunkDemoKeyboard.y)/3.0f;
cpFloat rate = ChipmunkDemoKeyboard.x*10.0f*coef;
cpSimpleMotorSetRate(motor, rate);
cpConstraintSetMaxForce(motor, (rate) ? 100000.0f : 0.0f);
int steps = 3;
cpFloat dt = 1.0f/60.0f/(cpFloat)steps;
for(int i=0; i<steps; i++){
cpSpaceStep(space, dt);
}
}
static void
StickySeparate(cpArbiter *arb, cpSpace *space, void *data)
{
cpConstraint *joint = (cpConstraint *)cpArbiterGetUserData(arb);
if(joint){
// The joint won't be removed until the step is done.
// Need to disable it so that it won't apply itself.
// Setting the force to 0 will do just that
cpConstraintSetMaxForce(joint, 0.0f);
// Perform the removal in a post-step() callback.
cpSpaceAddPostStepCallback(space, PostStepRemoveJoint, joint, NULL);
// NULL out the reference to the joint.
// Not required, but it's a good practice.
cpArbiterSetUserData(arb, NULL);
}
}
static void
update(cpSpace *space, double dt)
{
cpFloat coef = (2.0f + ChipmunkDemoKeyboard.y)/3.0f;
cpFloat rate = ChipmunkDemoKeyboard.x*30.0f*coef;
cpSimpleMotorSetRate(motor, rate);
cpConstraintSetMaxForce(motor, rate ? 1000000.0f : 0.0f);
cpSpaceStep(space, dt);
for(int i=0; i<numBalls; i++){
cpBody *ball = balls[i];
cpVect pos = cpBodyGetPosition(ball);
if(pos.x > 320.0f){
cpBodySetVelocity(ball, cpvzero);
cpBodySetPosition(ball, cpv(-224.0f, 200.0f));
}
}
}
/* Mouse handling is a bit tricky. We want the user to move
* tiles using the mouse but because tiles are dynamic bodies
* managed by Chipmunk2D, we cannot directly control them.
* This is resolved by creating a pivot joint between an
* invisible mouse body that we can control and the tile body
* that we cannot directly control.
*/
static void apply_mouse_motion(struct state* state)
{
struct mouse m;
update_mouse(&m);
int w, h;
get_screen_size(&w, &h);
int x = m.x_position * w;
int y = m.y_position * h;
cpVect mouse_pos = cpv(x, y);
cpVect new_point =
cpvlerp(cpBodyGetPosition(state->mouse_body), mouse_pos, 0.25f);
cpBodySetVelocity(
state->mouse_body,
cpvmult(cpvsub(new_point, cpBodyGetPosition(state->mouse_body)),
60.0f));
cpBodySetPosition(state->mouse_body, new_point);
if (m.left_click && state->mouse_joint == NULL) {
cpFloat radius = 5.0;
cpPointQueryInfo info = { 0 };
cpShape* shape = cpSpacePointQueryNearest(state->space, mouse_pos,
radius, GRAB_FILTER, &info);
if (shape && cpBodyGetMass(cpShapeGetBody(shape)) < INFINITY) {
cpVect nearest = (info.distance > 0.0f ? info.point : mouse_pos);
cpBody* body = cpShapeGetBody(shape);
state->mouse_joint =
cpPivotJointNew2(state->mouse_body, body, cpvzero,
cpBodyWorldToLocal(body, nearest));
cpConstraintSetMaxForce(state->mouse_joint, 5000000.0f);
cpConstraintSetErrorBias(state->mouse_joint,
cpfpow(1.0f - 0.15f, 60.0f));
cpSpaceAddConstraint(state->space, state->mouse_joint);
}
}
if (m.left_click == false && state->mouse_joint != NULL) {
cpSpaceRemoveConstraint(state->space, state->mouse_joint);
cpConstraintFree(state->mouse_joint);
state->mouse_joint = NULL;
}
}
static cpSpace *
init(void)
{
ChipmunkDemoMessageString = "Control the crane by moving the mouse. Press the down arrow to release.";
space = cpSpaceNew();
cpSpaceSetIterations(space, 30);
cpSpaceSetGravity(space, cpv(0, -100));
cpSpaceSetDamping(space, 0.8);
cpBody *staticBody = cpSpaceGetStaticBody(space);
cpShape *shape;
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-320,-240), cpv(320,-240), 0.0f));
cpShapeSetElasticity(shape, 1.0f);
cpShapeSetFriction(shape, 1.0f);
cpShapeSetLayers(shape, NOT_GRABABLE_MASK);
// Add a body for the dolly.
dollyBody = cpSpaceAddBody(space, cpBodyNew(10, INFINITY));
cpBodySetPos(dollyBody, cpv(0, 100));
// Add a block so you can see it.
cpSpaceAddShape(space, cpBoxShapeNew(dollyBody, 30, 30));
// Add a groove joint for it to move back and forth on.
cpSpaceAddConstraint(space, cpGrooveJointNew(staticBody, dollyBody, cpv(-250, 100), cpv(250, 100), cpvzero));
// Add a pivot joint to act as a servo motor controlling it's position
// By updating the anchor points of the pivot joint, you can move the dolly.
dollyServo = cpSpaceAddConstraint(space, cpPivotJointNew(staticBody, dollyBody, cpBodyGetPos(dollyBody)));
// Max force the dolly servo can generate.
cpConstraintSetMaxForce(dollyServo, 10000);
// Max speed of the dolly servo
cpConstraintSetMaxBias(dollyServo, 100);
// You can also change the error bias to control how it slows down.
//cpConstraintSetErrorBias(dollyServo, 0.2);
// Add the crane hook.
cpBody *hookBody = cpSpaceAddBody(space, cpBodyNew(1, INFINITY));
cpBodySetPos(hookBody, cpv(0, 50));
// Add a sensor shape for it. This will be used to figure out when the hook touches a box.
shape = cpSpaceAddShape(space, cpCircleShapeNew(hookBody, 10, cpvzero));
cpShapeSetSensor(shape, cpTrue);
cpShapeSetCollisionType(shape, HOOK_SENSOR);
// Add a slide joint to act as a winch motor
// By updating the max length of the joint you can make it pull up the load.
winchServo = cpSpaceAddConstraint(space, cpSlideJointNew(dollyBody, hookBody, cpvzero, cpvzero, 0, INFINITY));
// Max force the dolly servo can generate.
cpConstraintSetMaxForce(winchServo, 30000);
// Max speed of the dolly servo
cpConstraintSetMaxBias(winchServo, 60);
// TODO cleanup
// Finally a box to play with
cpBody *boxBody = cpSpaceAddBody(space, cpBodyNew(30, cpMomentForBox(30, 50, 50)));
cpBodySetPos(boxBody, cpv(200, -200));
// Add a block so you can see it.
shape = cpSpaceAddShape(space, cpBoxShapeNew(boxBody, 50, 50));
cpShapeSetFriction(shape, 0.7);
cpShapeSetCollisionType(shape, CRATE);
cpSpaceAddCollisionHandler(space, HOOK_SENSOR, CRATE, (cpCollisionBeginFunc)HookCrate, NULL, NULL, NULL, NULL);
return space;
}
cpSpace *Chains::Init()
{
ChipmunkDemo::Init();
space = cpSpaceNew();
cpSpaceSetIterations(space, 30);
cpSpaceSetGravity(space, cpv(0, -100));
cpSpaceSetSleepTimeThreshold(space, 0.5f);
cpBody *body, *staticBody = cpSpaceGetStaticBody(space);
cpShape *shape;
// Create segments around the edge of the screen.
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-320,-240), cpv(-320,240), 0.0f));
cpShapeSetElasticity(shape, 1.0f);
cpShapeSetFriction(shape, 1.0f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(320,-240), cpv(320,240), 0.0f));
cpShapeSetElasticity(shape, 1.0f);
cpShapeSetFriction(shape, 1.0f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-320,-240), cpv(320,-240), 0.0f));
cpShapeSetElasticity(shape, 1.0f);
cpShapeSetFriction(shape, 1.0f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-320,240), cpv(320,240), 0.0f));
cpShapeSetElasticity(shape, 1.0f);
cpShapeSetFriction(shape, 1.0f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
cpFloat mass = 1;
cpFloat width = 20;
cpFloat height = 30;
cpFloat spacing = width*0.3;
// Add lots of boxes.
for(int i=0; i<CHAIN_COUNT; i++){
cpBody *prev = NULL;
for(int j=0; j<LINK_COUNT; j++){
cpVect pos = cpv(40*(i - (CHAIN_COUNT - 1)/2.0), 240 - (j + 0.5)*height - (j + 1)*spacing);
body = cpSpaceAddBody(space, cpBodyNew(mass, cpMomentForBox(mass, width, height)));
cpBodySetPosition(body, pos);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(body, cpv(0, (height - width)/2.0), cpv(0, (width - height)/2.0), width/2.0));
cpShapeSetFriction(shape, 0.8f);
cpFloat breakingForce = 80000;
cpConstraint *constraint = NULL;
if(prev == NULL){
constraint = cpSpaceAddConstraint(space, cpSlideJointNew(body, staticBody, cpv(0, height/2), cpv(pos.x, 240), 0, spacing));
} else {
constraint = cpSpaceAddConstraint(space, cpSlideJointNew(body, prev, cpv(0, height/2), cpv(0, -height/2), 0, spacing));
}
cpConstraintSetMaxForce(constraint, breakingForce);
cpConstraintSetPostSolveFunc(constraint, BreakableJointPostSolve);
cpConstraintSetCollideBodies(constraint, cpFalse);
prev = body;
}
}
cpFloat radius = 15.0f;
body = cpSpaceAddBody(space, cpBodyNew(10.0f, cpMomentForCircle(10.0f, 0.0f, radius, cpvzero)));
cpBodySetPosition(body, cpv(0, -240 + radius+5));
cpBodySetVelocity(body, cpv(0, 300));
shape = cpSpaceAddShape(space, cpCircleShapeNew(body, radius, cpvzero));
cpShapeSetElasticity(shape, 0.0f);
cpShapeSetFriction(shape, 0.9f);
return space;
}
void SG_CALL sgPhysicsConstraintSetMaxForce(SGPhysicsConstraint* constr, float max)
{
cpConstraintSetMaxForce(constr->handle, max);
}
void CCJoint::setMaxForce(cpFloat maxForce)
{
cpConstraintSetMaxForce(this->m_constraint, maxForce);
}
