const CBoundingBoxAligned CModel::GetObjectSelectionBoundsRec()
{
CBoundingBoxAligned objBounds = GetObjectBounds(); // updates the (children-not-included) object-space bounds if necessary
// now extend these bounds to include the props' selection bounds (if any)
for (size_t i = 0; i < m_Props.size(); ++i)
{
const Prop& prop = m_Props[i];
if (prop.m_Hidden)
continue; // prop is hidden from rendering, so it also shouldn't be used for selection
CBoundingBoxAligned propSelectionBounds = prop.m_Model->GetObjectSelectionBoundsRec();
if (propSelectionBounds.IsEmpty())
continue; // submodel does not wish to participate in selection box, exclude it
// We have the prop's bounds in its own object-space; now we need to transform them so they can be properly added
// to the bounds in our object-space. For that, we need the transform of the prop attachment point.
//
// We have the prop point information; however, it's not trivial to compute its exact location in our object-space
// since it may or may not be attached to a bone (see SPropPoint), which in turn may or may not be in the middle of
// an animation. The bone matrices might be of interest, but they're really only meant to be used for the animation
// system and are quite opaque to use from the outside (see @ref ValidatePosition).
//
// However, a nice side effect of ValidatePosition is that it also computes the absolute world-space transform of
// our props and sets it on their respective models. In particular, @ref ValidatePosition will compute the prop's
// world-space transform as either
//
// T' = T x B x O
// or
// T' = T x O
//
// where T' is the prop's world-space transform, T is our world-space transform, O is the prop's local
// offset/rotation matrix, and B is an optional transformation matrix of the bone the prop is attached to
// (taking into account animation and everything).
//
// From this, it is clear that either O or B x O is the object-space transformation matrix of the prop. So,
// all we need to do is apply our own inverse world-transform T^(-1) to T' to get our desired result. Luckily,
// this is precomputed upon setting the transform matrix (see @ref SetTransform), so it is free to fetch.
CMatrix3D propObjectTransform = prop.m_Model->GetTransform(); // T'
propObjectTransform.Concatenate(GetInvTransform()); // T^(-1) x T'
// Transform the prop's bounds into our object coordinate space
CBoundingBoxAligned transformedPropSelectionBounds;
propSelectionBounds.Transform(propObjectTransform, transformedPropSelectionBounds);
objBounds += transformedPropSelectionBounds;
}
return objBounds;
}
/////////////////////////////////////////////////////////////////////////////////////////////////////////////
// ValidatePosition: ensure that current transform and bone matrices are both uptodate
void CModel::ValidatePosition()
{
if (m_PositionValid)
{
ENSURE(!m_Parent || m_Parent->m_PositionValid);
return;
}
if (m_Parent && !m_Parent->m_PositionValid)
{
// Make sure we don't base our calculations on
// a parent animation state that is out of date.
m_Parent->ValidatePosition();
// Parent will recursively call our validation.
ENSURE(m_PositionValid);
return;
}
if (m_Anim && m_BoneMatrices)
{
// PROFILE( "generating bone matrices" );
ENSURE(m_pModelDef->GetNumBones() == m_Anim->m_AnimDef->GetNumKeys());
m_Anim->m_AnimDef->BuildBoneMatrices(m_AnimTime, m_BoneMatrices, !(m_Flags & MODELFLAG_NOLOOPANIMATION));
}
else if (m_BoneMatrices)
{
// Bones but no animation - probably a buggy actor forgot to set up the animation,
// so just render it in its bind pose
for (size_t i = 0; i < m_pModelDef->GetNumBones(); i++)
{
m_BoneMatrices[i].SetIdentity();
m_BoneMatrices[i].Rotate(m_pModelDef->GetBones()[i].m_Rotation);
m_BoneMatrices[i].Translate(m_pModelDef->GetBones()[i].m_Translation);
}
}
// For CPU skinning, we precompute as much as possible so that the only
// per-vertex work is a single matrix*vec multiplication.
// For GPU skinning, we try to minimise CPU work by doing most computation
// in the vertex shader instead.
// Using g_Renderer.m_Options to detect CPU vs GPU is a bit hacky,
// and this doesn't allow the setting to change at runtime, but there isn't
// an obvious cleaner way to determine what data needs to be computed,
// and GPU skinning is a rarely-used experimental feature anyway.
bool worldSpaceBoneMatrices = !g_Renderer.m_Options.m_GPUSkinning;
bool computeBlendMatrices = !g_Renderer.m_Options.m_GPUSkinning;
if (m_BoneMatrices && worldSpaceBoneMatrices)
{
// add world-space transformation to m_BoneMatrices
const CMatrix3D transform = GetTransform();
for (size_t i = 0; i < m_pModelDef->GetNumBones(); i++)
m_BoneMatrices[i].Concatenate(transform);
}
// our own position is now valid; now we can safely update our props' positions without fearing
// that doing so will cause a revalidation of this model (see recursion above).
m_PositionValid = true;
// re-position and validate all props
for (size_t j = 0; j < m_Props.size(); ++j)
{
const Prop& prop=m_Props[j];
CMatrix3D proptransform = prop.m_Point->m_Transform;;
if (prop.m_Point->m_BoneIndex != 0xff)
{
CMatrix3D boneMatrix = m_BoneMatrices[prop.m_Point->m_BoneIndex];
if (!worldSpaceBoneMatrices)
boneMatrix.Concatenate(GetTransform());
proptransform.Concatenate(boneMatrix);
}
else
{
// not relative to any bone; just apply world-space transformation (i.e. relative to object-space origin)
proptransform.Concatenate(m_Transform);
}
prop.m_Model->SetTransform(proptransform);
prop.m_Model->ValidatePosition();
}
if (m_BoneMatrices)
{
for (size_t i = 0; i < m_pModelDef->GetNumBones(); i++)
{
m_BoneMatrices[i] = m_BoneMatrices[i] * m_pModelDef->GetInverseBindBoneMatrices()[i];
}
// Note: there is a special case of joint influence, in which the vertex
// is influenced by the bind-shape transform instead of a particular bone,
// which we indicate with the blending bone ID set to the total number
// of bones. But since we're skinning in world space, we use the model's
// world space transform and store that matrix in this special index.
// (see http://trac.wildfiregames.com/ticket/1012)
m_BoneMatrices[m_pModelDef->GetNumBones()] = m_Transform;
if (computeBlendMatrices)
m_pModelDef->BlendBoneMatrices(m_BoneMatrices);
}
}
