static cpFloat
getImpulse(cpPinJoint *joint)
{
return cpfabs(joint->jnAcc);
}
static cpFloat
getImpulse(cpRatchetJoint *joint)
{
return cpfabs(joint->jAcc);
}
static cpFloat
getImpulse(cpSimpleMotor *joint)
{
return cpfabs(joint->jAcc);
}
cpFloat
cpAreaForCircle(cpFloat r1, cpFloat r2)
{
return (cpFloat)M_PI*cpfabs(r1*r1 - r2*r2);
}
static cpFloat
getImpulse(cpGearJoint *joint)
{
return cpfabs(joint->jAcc);
}
iBOOL mwInitLevel015( void )
{
mwInitSpace(CurrLevelNum);
cpBody *body;
cpBody *staticBody = &(mwSpace->staticBody);
cpShape *shape;
cpFloat radius = WATER_RADIUS;
for(int i=0; i<2; i++){
for(int j=0; j<5; j++){
cpVect pos = cpv((j)*8+31,(i)*8+83);
body = cpSpaceAddBody(mwSpace, cpBodyNew(40.0f, cpMomentForCircle(40.0f, 0.0f, radius, cpvzero)));
cpBodySetPos(body, pos);
cpBodySetID(body,i*50+j);
body->v = cpv(body->v.x,-(cpfabs(body->v.y)));
shape = cpSpaceAddShape(mwSpace, cpCircleShapeNew(body, radius, cpvzero));
shape->e = WATER_E;
shape->u = WATER_U;
}
}
for(int i=0; i<2; i++){
for(int j=0; j<10; j++){
cpVect pos = cpv((j)*8+20,(i)*8+211);
body = cpSpaceAddBody(mwSpace, cpBodyNew(40.0f, cpMomentForCircle(40.0f, 0.0f, radius, cpvzero)));
cpBodySetPos(body, pos);
cpBodySetID(body,i*50+j);
body->v = cpv(body->v.x,-(cpfabs(body->v.y)));
shape = cpSpaceAddShape(mwSpace, cpCircleShapeNew(body, radius, cpvzero));
shape->e = WATER_E;
shape->u = WATER_U;
}
}
mwLevelWordInit(CurrLevelNum);
mwLevelDuckInit(CurrLevelNum);
mwLevelPipeInit(CurrLevelNum);
mwLevelWaitInit(CurrLevelNum);
mwLevelDrawBKwall();
i51KitG2DrawImage(mwContainer, MudLevel015, iNULL, iNULL);
i51KitG2DrawImage(mwContainer, RockLevel015, iNULL, iNULL);
mwLevelDrawPause();
mwLevelDrawRestart();
mwLevelOrganInit(CurrLevelNum);
i51AdeStdMemcpy16( (void *)TempScreenBuf, (void *)mwScreenBuffer, SCREEN_HEIGHT*SCREEN_WIDTH*2);
mwTempScreenBufUpdate(CurrLevelNum);
mwLevelSpeedKeepInit(CurrLevelNum);
mwLevelDrawDuck();
mwLevelDrawOrgan();
TimeLevelStart = i51AdeOsGetTick();
return iTRUE;
}
static cpFloat
getImpulse(cpConstraint *joint)
{
return cpfabs(((cpSlideJoint *)joint)->jnAcc);
}
cpBool Buoyancy::WaterPreSolve(cpArbiter *arb, cpSpace *space, void *ptr)
{
CP_ARBITER_GET_SHAPES(arb, water, poly);
cpBody *body = cpShapeGetBody(poly);
// Get the top of the water sensor bounding box to use as the water level.
cpFloat level = cpShapeGetBB(water).t;
// Clip the polygon against the water level
int count = cpPolyShapeGetCount(poly);
int clippedCount = 0;
#ifdef _MSC_VER
// MSVC is pretty much the only compiler in existence that doesn't support variable sized arrays.
cpVect clipped[10];
#else
cpVect clipped[count + 1];
#endif
for(int i=0, j=count-1; i<count; j=i, i++){
cpVect a = cpBodyLocalToWorld(body, cpPolyShapeGetVert(poly, j));
cpVect b = cpBodyLocalToWorld(body, cpPolyShapeGetVert(poly, i));
if(a.y < level){
clipped[clippedCount] = a;
clippedCount++;
}
cpFloat a_level = a.y - level;
cpFloat b_level = b.y - level;
if(a_level*b_level < 0.0f){
cpFloat t = cpfabs(a_level)/(cpfabs(a_level) + cpfabs(b_level));
clipped[clippedCount] = cpvlerp(a, b, t);
clippedCount++;
}
}
// Calculate buoyancy from the clipped polygon area
cpFloat clippedArea = cpAreaForPoly(clippedCount, clipped, 0.0f);
cpFloat displacedMass = clippedArea*FLUID_DENSITY;
cpVect centroid = cpCentroidForPoly(clippedCount, clipped);
cpDataPointer data = ptr;
DrawPolygon(clippedCount, clipped, 0.0f, RGBAColor(0, 0, 1, 1), RGBAColor(0, 0, 1, 0.1f), data);
DrawDot(5, centroid, RGBAColor(0, 0, 1, 1), data);
cpFloat dt = cpSpaceGetCurrentTimeStep(space);
cpVect g = cpSpaceGetGravity(space);
// Apply the buoyancy force as an impulse.
cpBodyApplyImpulseAtWorldPoint(body, cpvmult(g, -displacedMass*dt), centroid);
// Apply linear damping for the fluid drag.
cpVect v_centroid = cpBodyGetVelocityAtWorldPoint(body, centroid);
cpFloat k = k_scalar_body(body, centroid, cpvnormalize(v_centroid));
cpFloat damping = clippedArea*FLUID_DRAG*FLUID_DENSITY;
cpFloat v_coef = cpfexp(-damping*dt*k); // linear drag
// cpFloat v_coef = 1.0/(1.0 + damping*dt*cpvlength(v_centroid)*k); // quadratic drag
cpBodyApplyImpulseAtWorldPoint(body, cpvmult(cpvsub(cpvmult(v_centroid, v_coef), v_centroid), 1.0/k), centroid);
// Apply angular damping for the fluid drag.
cpVect cog = cpBodyLocalToWorld(body, cpBodyGetCenterOfGravity(body));
cpFloat w_damping = cpMomentForPoly(FLUID_DRAG*FLUID_DENSITY*clippedArea, clippedCount, clipped, cpvneg(cog), 0.0f);
cpBodySetAngularVelocity(body, cpBodyGetAngularVelocity(body)*cpfexp(-w_damping*dt/cpBodyGetMoment(body)));
return cpTrue;
}
static inline cpFloat
cpBBProximity(cpBB a, cpBB b)
{
return cpfabs(a.l + a.r - b.l - b.r) + cpfabs(a.b + b.t - b.b - b.t);
}
static cpFloat
getImpulse(cpRotaryLimitJoint *joint)
{
return cpfabs(joint->jAcc);
}
