/* 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;
}
}
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 RigidBody2D::SetVelocity(const Vector2f& velocity)
{
cpBodySetVelocity(m_handle, cpv(velocity.x, velocity.y));
}
cpSpace *Buoyancy::Init()
{
ChipmunkDemo::Init();
space = cpSpaceNew();
cpSpaceSetIterations(space, 30);
cpSpaceSetGravity(space, cpv(0, -500));
// cpSpaceSetDamping(space, 0.5);
cpSpaceSetSleepTimeThreshold(space, 0.5f);
cpSpaceSetCollisionSlop(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);
{
// Add the edges of the bucket
cpBB bb = cpBBNew(-300, -200, 100, 0);
cpFloat radius = 5.0f;
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(bb.l, bb.b), cpv(bb.l, bb.t), radius));
cpShapeSetElasticity(shape, 1.0f);
cpShapeSetFriction(shape, 1.0f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(bb.r, bb.b), cpv(bb.r, bb.t), radius));
cpShapeSetElasticity(shape, 1.0f);
cpShapeSetFriction(shape, 1.0f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(bb.l, bb.b), cpv(bb.r, bb.b), radius));
cpShapeSetElasticity(shape, 1.0f);
cpShapeSetFriction(shape, 1.0f);
cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
// Add the sensor for the water.
shape = cpSpaceAddShape(space, cpBoxShapeNew2(staticBody, bb, 0.0));
cpShapeSetSensor(shape, cpTrue);
cpShapeSetCollisionType(shape, 1);
}
{
cpFloat width = 200.0f;
cpFloat height = 50.0f;
cpFloat mass = 0.3*FLUID_DENSITY*width*height;
cpFloat moment = cpMomentForBox(mass, width, height);
body = cpSpaceAddBody(space, cpBodyNew(mass, moment));
cpBodySetPosition(body, cpv(-50, -100));
cpBodySetVelocity(body, cpv(0, -100));
cpBodySetAngularVelocity(body, 1);
shape = cpSpaceAddShape(space, cpBoxShapeNew(body, width, height, 0.0));
cpShapeSetFriction(shape, 0.8f);
}
{
cpFloat width = 40.0f;
cpFloat height = width*2;
cpFloat mass = 0.3*FLUID_DENSITY*width*height;
cpFloat moment = cpMomentForBox(mass, width, height);
body = cpSpaceAddBody(space, cpBodyNew(mass, moment));
cpBodySetPosition(body, cpv(-200, -50));
cpBodySetVelocity(body, cpv(0, -100));
cpBodySetAngularVelocity(body, 1);
shape = cpSpaceAddShape(space, cpBoxShapeNew(body, width, height, 0.0));
cpShapeSetFriction(shape, 0.8f);
}
cpCollisionHandler *handler = cpSpaceAddCollisionHandler(space, 1, 0);
handler->preSolveFunc = (cpCollisionPreSolveFunc)WaterPreSolve;
handler->userData = this;
return space;
}
