// Bounding Sphere Tests
TEST_F(BBoxTest, BoundingSphereWorks) {
BBox b (Point (0, 0, 0), Point (1, 1, 1));
Point center;
float radius;
b.BoundingSphere (¢er, &radius);
EXPECT_EQ (.5, center.x);
EXPECT_EQ (.5, center.y);
EXPECT_EQ (.5, center.z);
EXPECT_EQ (sqrtf(.75), radius);
}
TEST_F(BBoxTest, BoundingSphereDegenerateWorks) {
BBox b (Point (0, 0, 0), Point (0, 0, 0));
Point center;
float radius;
b.BoundingSphere (¢er, &radius);
EXPECT_EQ (0, center.x);
EXPECT_EQ (0, center.y);
EXPECT_EQ (0, center.z);
EXPECT_EQ (0, radius);
}
//--------------------------------------------------------------------------------------
//
// ProcessVertices
//
// After all of the vertices have been loaded ProcessVertices is called to create the
// associated data with the hair vertices, which includes attributes like tangents,strand
// length, and transformations. Also the hair type is stored with each vertex which
// allows different simulation parameters for different sections of the hair.
//
//--------------------------------------------------------------------------------------
void TressFXAssetLoader::ProcessVertices()
{
// construct local and global transforms for each hair strand.
ConstructTransforms();
// compute tangent vectors
ComputeStrandTangent();
// compute distances to root vertices
ComputeDistanceToRoot();
m_HairAsset.m_pVertices = new XMFLOAT4[m_HairAsset.m_NumTotalHairVertices];
m_HairAsset.m_pHairStrandType = new int[m_HairAsset.m_NumTotalHairStrands];
if (m_usingPerStrandTexCoords)
{
m_HairAsset.m_pStrandTexCoords = new XMFLOAT2[m_HairAsset.m_NumTotalHairStrands];
}
else
{
m_HairAsset.m_pStrandTexCoords = NULL;
}
m_HairAsset.m_pTangents = new XMFLOAT4[m_HairAsset.m_NumTotalHairVertices];
// Initialize the hair strands and compute tangents
for ( int i = 0; i < m_HairAsset.m_NumTotalHairVertices; i++ )
{
m_HairAsset.m_pTangents[i].x = m_Vertices[i].tangent.x;
m_HairAsset.m_pTangents[i].y = m_Vertices[i].tangent.y;
m_HairAsset.m_pTangents[i].z = m_Vertices[i].tangent.z;
}
m_HairAsset.m_pRestLengths = new float[m_HairAsset.m_NumTotalHairVertices];
int index = 0;
// Calculate rest lengths
for ( int i = 0; i < m_HairAsset.m_NumTotalHairStrands; i++ )
{
int indexRootVert = i * m_HairAsset.m_NumOfVerticesInStrand;
for ( int j = 0; j < m_HairAsset.m_NumOfVerticesInStrand - 1; j++ )
{
m_HairAsset.m_pRestLengths[index++] = (m_Vertices[indexRootVert + j].position - m_Vertices[indexRootVert + j + 1].position).Length();
}
// Since number of edges are one less than number of vertices in hair strand, below line acts as a placeholder.
m_HairAsset.m_pRestLengths[index++] = 0;
}
assert(index == m_HairAsset.m_NumTotalHairVertices);
m_HairAsset.m_pRefVectors = new XMFLOAT4[m_HairAsset.m_NumTotalHairVertices];
m_HairAsset.m_pGlobalRotations = new XMFLOAT4[m_HairAsset.m_NumTotalHairVertices];
m_HairAsset.m_pLocalRotations = new XMFLOAT4[m_HairAsset.m_NumTotalHairVertices];
m_HairAsset.m_pTriangleVertices = new StrandVertex[m_HairAsset.m_NumTotalHairVertices];
m_HairAsset.m_pThicknessCoeffs = new float[m_HairAsset.m_NumTotalHairVertices];
m_HairAsset.m_pFollowRootOffset = new XMFLOAT4[m_HairAsset.m_NumTotalHairStrands];
m_HairAsset.m_LineIndices.reserve(m_HairAsset.m_NumTotalHairVertices * 2);
m_HairAsset.m_TriangleIndices.reserve(m_HairAsset.m_NumTotalHairVertices * 6);
int id=0;
index = 0;
TressFXStrand* pGuideHair = NULL;
int indexGuideHairStrand = -1;
// initialize the rest of the hair data
for ( int i = 0; i < m_HairAsset.m_NumTotalHairStrands; i++ )
{
int indexRootVert = i * m_HairAsset.m_NumOfVerticesInStrand;
for ( int j = 0; j < m_HairAsset.m_NumOfVerticesInStrand - 1; j++ )
{
// line indices
m_HairAsset.m_LineIndices.push_back(id);
m_HairAsset.m_LineIndices.push_back(id + 1);
// triangle indices
m_HairAsset.m_TriangleIndices.push_back(2 * id);
m_HairAsset.m_TriangleIndices.push_back(2 * id + 1);
m_HairAsset.m_TriangleIndices.push_back(2 * id + 2);
m_HairAsset.m_TriangleIndices.push_back(2 * id + 2);
m_HairAsset.m_TriangleIndices.push_back(2 * id + 1);
m_HairAsset.m_TriangleIndices.push_back(2 * id + 3);
id++;
}
id++;
TressFXHairVertex* vertices = &m_Vertices[indexRootVert];
for ( int j = 0; j < m_HairAsset.m_NumOfVerticesInStrand; j++ )
{
// triangle vertices
StrandVertex strandVertex;
strandVertex.position = XMFLOAT3(vertices[j].position.x, vertices[j].position.y, vertices[j].position.z);
strandVertex.tangent = XMFLOAT3(vertices[j].tangent.x, vertices[j].tangent.y, vertices[j].tangent.z);
strandVertex.texcoord = XMFLOAT4(vertices[j].texcoord.x, vertices[j].texcoord.y, vertices[j].texcoord.z, 0);
m_HairAsset.m_pTriangleVertices[index] = strandVertex;
float tVal = m_HairAsset.m_pTriangleVertices[index].texcoord.z;
m_HairAsset.m_pThicknessCoeffs[index] = sqrt(1.f - tVal * tVal);
XMFLOAT4 v;
// temp vertices
v.x = vertices[j].position.x;
v.y = vertices[j].position.y;
v.z = vertices[j].position.z;
v.w = vertices[j].invMass;
m_HairAsset.m_pVertices[index] = v;
// global rotations
v.x = vertices[j].globalTransform.GetRotation().x;
v.y = vertices[j].globalTransform.GetRotation().y;
v.z = vertices[j].globalTransform.GetRotation().z;
v.w = vertices[j].globalTransform.GetRotation().w;
m_HairAsset.m_pGlobalRotations[index] = v;
// local rotations
v.x = vertices[j].localTransform.GetRotation().x;
v.y = vertices[j].localTransform.GetRotation().y;
v.z = vertices[j].localTransform.GetRotation().z;
v.w = vertices[j].localTransform.GetRotation().w;
m_HairAsset.m_pLocalRotations[index] = v;
// ref vectors
v.x = vertices[j].referenceVector.x;
v.y = vertices[j].referenceVector.y;
v.z = vertices[j].referenceVector.z;
m_HairAsset.m_pRefVectors[index].x = v.x;
m_HairAsset.m_pRefVectors[index].y = v.y;
m_HairAsset.m_pRefVectors[index].z = v.z;
index++;
}
int groupId = m_HairStrands[i].m_GroupID;
m_HairAsset.m_pHairStrandType[i] = groupId;
if ( m_usingPerStrandTexCoords )
{
m_HairAsset.m_pStrandTexCoords[i] = m_HairStrands[i].m_texCoord;
}
if ( m_HairStrands[i].m_bGuideHair )
{
indexGuideHairStrand = i;
pGuideHair = &m_HairStrands[i];
m_HairAsset.m_pFollowRootOffset[i] = XMFLOAT4(0, 0, 0, (float)indexGuideHairStrand); // forth component is an index to the guide hair strand. For guide hair, it points itself.
}
else
{
assert(pGuideHair);
tressfx_vec3& offset = m_SlaveOffset[i];
m_HairAsset.m_pFollowRootOffset[i] = XMFLOAT4(offset.x, offset.y, offset.z, (float)indexGuideHairStrand);
}
}
// Find the bounding sphere
BBox bBox;
for ( int i = 0; i < (int)m_Vertices.size(); ++i )
{
const TressFXHairVertex& vertex = m_Vertices[i];
bBox = Union(bBox, Float3(vertex.position.x, vertex.position.y, vertex.position.z));
}
Float3 c; float radius;
bBox.BoundingSphere(&c, &radius);
m_HairAsset.m_bSphere.center = XMFLOAT3(c.x, c.y, c.z);
m_HairAsset.m_bSphere.radius = radius;
}
