func newBody(shape Shape) *body {
b := &body{}
b.shape = shape
b.imass = 0 // no mass, static body by default
b.friction = 0.5 // good to have some friction
b.world = lin.NewT().SetI() // world transform
b.guess = lin.NewT().SetI() // predicted world transform
// allocate linear and angular motion data
b.lvel = lin.NewV3()
b.lfor = lin.NewV3()
b.avel = lin.NewV3()
b.afor = lin.NewV3()
b.iitw = lin.NewM3().Set(lin.M3I)
b.iit = lin.NewV3()
// allocate scratch variables
b.coi = &C.BoxBoxInput{}
b.cor = &C.BoxBoxResults{}
b.m0 = &lin.M3{}
b.m1 = &lin.M3{}
b.v0 = &lin.V3{}
b.t0 = lin.NewT()
// create a unique body identifier
bodyUuidMutex.Lock()
b.bid = bodyUuid
if bodyUuid++; bodyUuid == 0 {
log.Printf("Overflow: dev error. Unique body id wrapped.")
}
bodyUuidMutex.Unlock()
return b
}
// newSolverBody allocates space for body specific solver information.
// This is expected to be called for a movable body, ie. one that has mass
// and can have velocity.
func newSolverBody(bod *body) *solverBody {
sb := &solverBody{}
sb.oBody = bod // reference
sb.world = lin.NewT().Set(bod.world)
sb.linearVelocity = lin.NewV3().Set(bod.lvel)
sb.angularVelocity = lin.NewV3().Set(bod.avel)
sb.deltaLinearVelocity = lin.NewV3()
sb.deltaAngularVelocity = lin.NewV3()
sb.pushVelocity = lin.NewV3()
sb.turnVelocity = lin.NewV3()
sb.invMass = lin.NewV3().SetS(bod.imass, bod.imass, bod.imass)
sb.t0 = lin.NewT()
sb.v0 = lin.NewV3()
return sb
}
func TestSphereAabb(t *testing.T) {
sp := Shape(NewSphere(1))
ab := sp.Aabb(lin.NewT().SetI(), &Abox{}, 0.01)
if ab.Sx != -1.01 || ab.Sy != -1.01 || ab.Sz != -1.01 || ab.Lx != 1.01 || ab.Ly != 1.01 || ab.Lz != 1.01 {
t.Error("Invalid bounding box for Sphere")
}
}
func TestBoxAabb(t *testing.T) {
bx := Shape(NewBox(1, 1, 1))
ab := bx.Aabb(lin.NewT().SetI(), &Abox{}, 0.01)
if ab.Sx != -1.01 || ab.Sy != -1.01 || ab.Sz != -1.01 || ab.Lx != 1.01 || ab.Ly != 1.01 || ab.Lz != 1.01 {
t.Error("Invalid bounding box for Box")
}
}
// fixedSolverBody lazy initializes and returns the single fixed
// solver body that is used by all static solver bodies.
func fixedSolverBody() *solverBody {
if fsb == nil {
fsb = &solverBody{}
fsb.oBody = nil
fsb.world = lin.NewT().SetI()
fsb.linearVelocity = lin.NewV3()
fsb.angularVelocity = lin.NewV3()
fsb.deltaLinearVelocity = lin.NewV3()
fsb.deltaAngularVelocity = lin.NewV3()
fsb.pushVelocity = lin.NewV3()
fsb.turnVelocity = lin.NewV3()
fsb.invMass = lin.NewV3()
fsb.t0 = lin.NewT()
fsb.v0 = lin.NewV3()
}
return fsb
}
// newPov allocates and initialzes a point of view transform.
func newPov(eng *engine, eid uint64) *pov {
p := &pov{eng: eng, eid: eid, visible: true}
p.at = lin.NewT()
p.scale = &lin.V3{X: 1, Y: 1, Z: 1}
// allocate scratch variables.
p.rot = lin.NewQ()
p.mm = &lin.M4{}
return p
}
// newCamera creates a default point of view that is looking down
// the positive Z axis.
func newCamera() *camera {
c := &camera{depth: true}
c.vt = VP
c.at = lin.NewT()
c.vm = &lin.M4{}
c.ivm = (&lin.M4{}).Set(lin.M4I)
c.pm = &lin.M4{}
c.ipm = &lin.M4{}
c.q0 = &lin.Q{}
c.xrot = lin.NewQ().SetAa(1, 0, 0, 0)
c.yrot = lin.NewQ().SetAa(0, 1, 0, 0)
c.v0 = &lin.V4{}
c.ray = &lin.V3{}
return c
}
func (b *body) World() *lin.T {
if b.world == nil {
b.world = lin.NewT().SetI()
}
return b.world
}