ShadowCameraTransform DirectionalLight::CalcShadowCameraTransform(const Vector3f& mainCameraPos, const Quaternion& mainCameraRot) const
{
Vector3f resultPos = mainCameraPos + mainCameraRot.GetForward() * GetHalfShadowArea();
Quaternion resultRot = GetTransform().GetTransformedRot();
float worldTexelSize = (GetHalfShadowArea()*2)/((float)(1 << GetShadowInfo().GetShadowMapSizeAsPowerOf2()));
Vector3f lightSpaceCameraPos = resultPos.Rotate(resultRot.Conjugate());
lightSpaceCameraPos.SetX(worldTexelSize * floor(lightSpaceCameraPos.GetX() / worldTexelSize));
lightSpaceCameraPos.SetY(worldTexelSize * floor(lightSpaceCameraPos.GetY() / worldTexelSize));
resultPos = lightSpaceCameraPos.Rotate(resultRot);
return ShadowCameraTransform(resultPos, resultRot);
}
void IndexedModel::CalcTangents()
{
m_tangents.clear();
m_tangents.reserve(m_positions.size());
for(unsigned int i = 0; i < m_positions.size(); i++)
m_tangents.push_back(Vector3f(0,0,0));
for(unsigned int i = 0; i < m_indices.size(); i += 3)
{
int i0 = m_indices[i];
int i1 = m_indices[i + 1];
int i2 = m_indices[i + 2];
Vector3f edge1 = m_positions[i1] - m_positions[i0];
Vector3f edge2 = m_positions[i2] - m_positions[i0];
float deltaU1 = m_texCoords[i1].GetX() - m_texCoords[i0].GetX();
float deltaU2 = m_texCoords[i2].GetX() - m_texCoords[i0].GetX();
float deltaV1 = m_texCoords[i1].GetY() - m_texCoords[i0].GetY();
float deltaV2 = m_texCoords[i2].GetY() - m_texCoords[i0].GetY();
float dividend = (deltaU1 * deltaV2 - deltaU2 * deltaV1);
float f = dividend == 0.0f ? 0.0f : 1.0f/dividend;
Vector3f tangent = Vector3f(0,0,0);
tangent.SetX(f * (deltaV2 * edge1.GetX() - deltaV1 * edge2.GetX()));
tangent.SetY(f * (deltaV2 * edge1.GetY() - deltaV1 * edge2.GetY()));
tangent.SetZ(f * (deltaV2 * edge1.GetZ() - deltaV1 * edge2.GetZ()));
//Bitangent example, in Java
// Vector3f bitangent = new Vector3f(0,0,0);
//
// bitangent.setX(f * (-deltaU2 * edge1.getX() - deltaU1 * edge2.getX()));
// bitangent.setX(f * (-deltaU2 * edge1.getY() - deltaU1 * edge2.getY()));
// bitangent.setX(f * (-deltaU2 * edge1.getZ() - deltaU1 * edge2.getZ()));
m_tangents[i0] += tangent;
m_tangents[i1] += tangent;
m_tangents[i2] += tangent;
}
for(unsigned int i = 0; i < m_tangents.size(); i++)
m_tangents[i] = m_tangents[i].Normalized();
}
void Mesh::CalcTangents(Vertex* vertices, int nVertices, INDEX* indices, int nIndices)
{
for(int i = 0; i < nIndices; i += 3)
{
Vertex v0 = vertices[indices[i]];
Vertex v1 = vertices[indices[i + 1]];
Vertex v2 = vertices[indices[i + 2]];
Vector3f edge1 = v1.Pos - v0.Pos;
Vector3f edge2 = v2.Pos - v0.Pos;
float deltaU1 = v1.TexCoord.GetX() - v0.TexCoord.GetX();
float deltaU2 = v2.TexCoord.GetX() - v0.TexCoord.GetX();
float deltaV1 = v1.TexCoord.GetY() - v0.TexCoord.GetY();
float deltaV2 = v2.TexCoord.GetY() - v0.TexCoord.GetY();
float f = 1.0f/(deltaU1 * deltaV2 - deltaU2 * deltaV1);
Vector3f tangent = Vector3f(0,0,0);
tangent.SetX(f * (deltaV2 * edge1.GetX() - deltaV1 * edge2.GetX()));
tangent.SetY(f * (deltaV2 * edge1.GetY() - deltaV1 * edge2.GetY()));
tangent.SetZ(f * (deltaV2 * edge1.GetZ() - deltaV1 * edge2.GetZ()));
//Bitangent example, in Java
// Vector3f bitangent = new Vector3f(0,0,0);
//
// bitangent.setX(f * (-deltaU2 * edge1.getX() - deltaU1 * edge2.getX()));
// bitangent.setX(f * (-deltaU2 * edge1.getY() - deltaU1 * edge2.getY()));
// bitangent.setX(f * (-deltaU2 * edge1.getZ() - deltaU1 * edge2.getZ()));
v0.Tangent += tangent;
v1.Tangent += tangent;
v2.Tangent += tangent;
}
for(int i = 0; i < nVertices; i++)
vertices[i].Tangent = vertices[i].Tangent.Normalized();
}