void PhysicsShape::addShape(cpShape* shape)
{
if (shape)
{
cpShapeSetUserData(shape, this);
cpShapeSetFilter(shape, cpShapeFilterNew(_group, CP_ALL_CATEGORIES, CP_ALL_CATEGORIES));
_cpShapes.push_back(shape);
}
}
static void
make_leg(cpSpace *space, cpFloat side, cpFloat offset, cpBody *chassis, cpBody *crank, cpVect anchor)
{
cpVect a, b;
cpShape *shape;
cpFloat leg_mass = 1.0f;
// make leg
a = cpvzero, b = cpv(0.0f, side);
cpBody *upper_leg = cpSpaceAddBody(space, cpBodyNew(leg_mass, cpMomentForSegment(leg_mass, a, b, 0.0f)));
cpBodySetPosition(upper_leg, cpv(offset, 0.0f));
shape = cpSpaceAddShape(space, cpSegmentShapeNew(upper_leg, a, b, seg_radius));
cpShapeSetFilter(shape, cpShapeFilterNew(1, CP_ALL_CATEGORIES, CP_ALL_CATEGORIES));
cpSpaceAddConstraint(space, cpPivotJointNew2(chassis, upper_leg, cpv(offset, 0.0f), cpvzero));
// lower leg
a = cpvzero, b = cpv(0.0f, -1.0f*side);
cpBody *lower_leg = cpSpaceAddBody(space, cpBodyNew(leg_mass, cpMomentForSegment(leg_mass, a, b, 0.0f)));
cpBodySetPosition(lower_leg, cpv(offset, -side));
shape = cpSpaceAddShape(space, cpSegmentShapeNew(lower_leg, a, b, seg_radius));
cpShapeSetFilter(shape, cpShapeFilterNew(1, CP_ALL_CATEGORIES, CP_ALL_CATEGORIES));
shape = cpSpaceAddShape(space, cpCircleShapeNew(lower_leg, seg_radius*2.0f, b));
cpShapeSetFilter(shape, cpShapeFilterNew(1, CP_ALL_CATEGORIES, CP_ALL_CATEGORIES));
cpShapeSetElasticity(shape, 0.0f);
cpShapeSetFriction(shape, 1.0f);
cpSpaceAddConstraint(space, cpPinJointNew(chassis, lower_leg, cpv(offset, 0.0f), cpvzero));
cpSpaceAddConstraint(space, cpGearJointNew(upper_leg, lower_leg, 0.0f, 1.0f));
cpConstraint *constraint;
cpFloat diag = cpfsqrt(side*side + offset*offset);
constraint = cpSpaceAddConstraint(space, cpPinJointNew(crank, upper_leg, anchor, cpv(0.0f, side)));
cpPinJointSetDist(constraint, diag);
constraint = cpSpaceAddConstraint(space, cpPinJointNew(crank, lower_leg, anchor, cpvzero));
cpPinJointSetDist(constraint, diag);
}
void PhysicsShape::setGroup(int group)
{
if (group < 0)
{
for (auto shape : _cpShapes)
{
cpShapeSetFilter(shape, cpShapeFilterNew(group, CP_ALL_CATEGORIES, CP_ALL_CATEGORIES));
}
}
_group = group;
}
static cpSpace *
init(void)
{
ChipmunkDemoMessageString = "Use the arrow keys to control the machine.";
cpSpace *space = cpSpaceNew();
cpSpaceSetIterations(space, 20);
cpSpaceSetGravity(space, cpv(0,-500));
cpBody *staticBody = cpSpaceGetStaticBody(space);
cpShape *shape;
cpVect a, b;
// 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);
cpFloat offset = 30.0f;
// make chassis
cpFloat chassis_mass = 2.0f;
a = cpv(-offset, 0.0f), b = cpv(offset, 0.0f);
cpBody *chassis = cpSpaceAddBody(space, cpBodyNew(chassis_mass, cpMomentForSegment(chassis_mass, a, b, 0.0f)));
shape = cpSpaceAddShape(space, cpSegmentShapeNew(chassis, a, b, seg_radius));
cpShapeSetFilter(shape, cpShapeFilterNew(1, CP_ALL_CATEGORIES, CP_ALL_CATEGORIES));
// make crank
cpFloat crank_mass = 1.0f;
cpFloat crank_radius = 13.0f;
cpBody *crank = cpSpaceAddBody(space, cpBodyNew(crank_mass, cpMomentForCircle(crank_mass, crank_radius, 0.0f, cpvzero)));
shape = cpSpaceAddShape(space, cpCircleShapeNew(crank, crank_radius, cpvzero));
cpShapeSetFilter(shape, cpShapeFilterNew(1, CP_ALL_CATEGORIES, CP_ALL_CATEGORIES));
cpSpaceAddConstraint(space, cpPivotJointNew2(chassis, crank, cpvzero, cpvzero));
cpFloat side = 30.0f;
int num_legs = 2;
for(int i=0; i<num_legs; i++){
make_leg(space, side, offset, chassis, crank, cpvmult(cpvforangle((cpFloat)(2*i+0)/(cpFloat)num_legs*M_PI), crank_radius));
make_leg(space, side, -offset, chassis, crank, cpvmult(cpvforangle((cpFloat)(2*i+1)/(cpFloat)num_legs*M_PI), crank_radius));
}
motor = cpSpaceAddConstraint(space, cpSimpleMotorNew(chassis, crank, 6.0f));
return space;
}
static cpSpace *
init(void)
{
ChipmunkDemoMessageString = "Use the arrow keys to control the machine.";
cpSpace *space = cpSpaceNew();
cpSpaceSetGravity(space, cpv(0, -600));
cpBody *staticBody = cpSpaceGetStaticBody(space);
cpShape *shape;
// beveling all of the line segments slightly helps prevent things from getting stuck on cracks
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-256,16), cpv(-256,300), 2.0f));
cpShapeSetElasticity(shape, 0.0f);
cpShapeSetFriction(shape, 0.5f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-256,16), cpv(-192,0), 2.0f));
cpShapeSetElasticity(shape, 0.0f);
cpShapeSetFriction(shape, 0.5f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-192,0), cpv(-192, -64), 2.0f));
cpShapeSetElasticity(shape, 0.0f);
cpShapeSetFriction(shape, 0.5f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-128,-64), cpv(-128,144), 2.0f));
cpShapeSetElasticity(shape, 0.0f);
cpShapeSetFriction(shape, 0.5f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-192,80), cpv(-192,176), 2.0f));
cpShapeSetElasticity(shape, 0.0f);
cpShapeSetFriction(shape, 0.5f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-192,176), cpv(-128,240), 2.0f));
cpShapeSetElasticity(shape, 0.0f);
cpShapeSetFriction(shape, 0.5f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-128,144), cpv(192,64), 2.0f));
cpShapeSetElasticity(shape, 0.0f);
cpShapeSetFriction(shape, 0.5f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
cpVect verts[] = {
cpv(-30,-80),
cpv(-30, 80),
cpv( 30, 64),
cpv( 30,-80),
};
cpBody *plunger = cpSpaceAddBody(space, cpBodyNew(1.0f, INFINITY));
cpBodySetPosition(plunger, cpv(-160,-80));
shape = cpSpaceAddShape(space, cpPolyShapeNew(plunger, 4, verts, cpTransformIdentity, 0.0));
cpShapeSetElasticity(shape, 1.0f);
cpShapeSetFriction(shape, 0.5f);
cpShapeSetFilter(shape, cpShapeFilterNew(CP_NO_GROUP, 1, 1));
// add balls to hopper
for(int i=0; i<numBalls; i++)
balls[i] = add_ball(space, cpv(-224 + i,80 + 64*i));
// add small gear
cpBody *smallGear = cpSpaceAddBody(space, cpBodyNew(10.0f, cpMomentForCircle(10.0f, 80, 0, cpvzero)));
cpBodySetPosition(smallGear, cpv(-160,-160));
cpBodySetAngle(smallGear, -M_PI_2);
shape = cpSpaceAddShape(space, cpCircleShapeNew(smallGear, 80.0f, cpvzero));
cpShapeSetFilter(shape, CP_SHAPE_FILTER_NONE);
cpSpaceAddConstraint(space, cpPivotJointNew2(staticBody, smallGear, cpv(-160,-160), cpvzero));
// add big gear
cpBody *bigGear = cpSpaceAddBody(space, cpBodyNew(40.0f, cpMomentForCircle(40.0f, 160, 0, cpvzero)));
cpBodySetPosition(bigGear, cpv(80,-160));
cpBodySetAngle(bigGear, M_PI_2);
shape = cpSpaceAddShape(space, cpCircleShapeNew(bigGear, 160.0f, cpvzero));
cpShapeSetFilter(shape, CP_SHAPE_FILTER_NONE);
cpSpaceAddConstraint(space, cpPivotJointNew2(staticBody, bigGear, cpv(80,-160), cpvzero));
// connect the plunger to the small gear.
cpSpaceAddConstraint(space, cpPinJointNew(smallGear, plunger, cpv(80,0), cpv(0,0)));
// connect the gears.
cpSpaceAddConstraint(space, cpGearJointNew(smallGear, bigGear, -M_PI_2, -2.0f));
// feeder mechanism
cpFloat bottom = -300.0f;
cpFloat top = 32.0f;
cpBody *feeder = cpSpaceAddBody(space, cpBodyNew(1.0f, cpMomentForSegment(1.0f, cpv(-224.0f, bottom), cpv(-224.0f, top), 0.0f)));
cpBodySetPosition(feeder, cpv(-224, (bottom + top)/2.0f));
cpFloat len = top - bottom;
shape = cpSpaceAddShape(space, cpSegmentShapeNew(feeder, cpv(0.0f, len/2.0f), cpv(0.0f, -len/2.0f), 20.0f));
cpShapeSetFilter(shape, GRAB_FILTER);
cpSpaceAddConstraint(space, cpPivotJointNew2(staticBody, feeder, cpv(-224.0f, bottom), cpv(0.0f, -len/2.0f)));
cpVect anchr = cpBodyWorldToLocal(feeder, cpv(-224.0f, -160.0f));
cpSpaceAddConstraint(space, cpPinJointNew(feeder, smallGear, anchr, cpv(0.0f, 80.0f)));
// motorize the second gear
motor = cpSpaceAddConstraint(space, cpSimpleMotorNew(staticBody, bigGear, 3.0f));
return space;
}
