Game Development Reference
In-Depth Information
Right Shoulder
Right Bicep
Right Forearm
Right Wrist
Right Hand
Left Thigh
Left Calf
Left Ankle
Left Foot
Left Toe
Right Thigh
Right Calf
Right Ankle
Right Foot
Right Toe
In this hierarchy there are 25 possible bones. In a simple low polygon
single mesh character you may have 1000 vertices. If each of these 1000
vertices is acted on by 25 bones, then there are 25 000 calculations to
perform rather than just 1000. This is 25 times as many calculations to do
than we would prefer. Our real-time engine needs much more focus over
which vertices are deformed by which bone. But, suppose that no vertex
is acted on by more than one bone. This can lead to some very unwanted
artefacts. Let's consider how the mesh at a knee joint may behave if each
vertex in the mesh is controlled by a single bone. As the joint rotates, the
vertices at the back of the knee that influence the calf can end up
overlapping the vertices for the thigh (see Figure 7.1). This can lead to
very bad nipping. At a distance this may be acceptable, but close up to
Figure 7.1 How vertex selection can result in poor quality rendering.
Search Nedrilad ::




Custom Search