void KaraokeVideoBackground::Render()
{
// Just in case
if ( !m_texture )
return;
// Get the current song timing in ms.
// This will only fit songs up to 71,000 hours, so if you got a larger one, change to int64
double current = g_application.GetTime();
// We're supposed to show m_decoder->getFramesPerSecond() frames in one second.
if ( current >= m_nextFrameTime )
{
// We don't care to adjust for the exact timing as we don't worry about the exact frame rate
m_nextFrameTime = current + m_millisecondsPerFrame - (current - m_nextFrameTime);
while ( true )
{
if ( !m_decoder->nextFrame( m_texture ) )
{
// End of video; restart
m_decoder->seek( 0.0 );
m_nextFrameTime = 0.0;
continue;
}
break;
}
}
// We got a frame. Draw it.
CRect vertCoords((float) m_displayLeft, (float) m_displayTop, (float) m_displayRight, (float) m_displayBottom );
CGUITexture::DrawQuad(vertCoords, 0xffffffff, m_texture );
}
void SoftConstrFunction::Evaluate(const arma::vec &x) {
// Vertex coordinates: First convert control points into vertices
// verCoords has the form of [x1 x2, x3... y1 y2 y3... z1 z2 z3]
// We will compute Jacobian w.r.t vertex variables first, then we compute
// Jacobian w.r.t actual variables using composition rules
vec vertCoords = this->P * x;
vec CPx;
CPx.set_size(this->refEdgeLens.n_elem);
int nVertVars = this->P.n_rows; // Number of vertex variables = 3 * #vertices
int nVerts = nVertVars / 3; // Number of vertices
int nEdges = this->refEdgeLens.n_elem; // Number of edges (#constraints)
// TODO: Make Jv to be attribute of class to avoid re-allocating each evaluation
// Jacobian w.r.t all vertex coordinates. Then this->J = Jv * P since x = P*c
mat Jv = zeros(nEdges, nVertVars);
// Iterate through all edges to compute function value and derivatives
for (int i = 0; i < nEdges; i++)
{
// An edge has two vertices
int vertID1 = edges(0, i);
int vertID2 = edges(1, i);
// Indices of x,y,z coordinates in the vector vertCoords [x1 x2, x3... y1 y2 y3... z1 z2 z3]
int x1Idx = vertID1;
int y1Idx = x1Idx + nVerts;
int z1Idx = y1Idx + nVerts;
int x2Idx = vertID2;
int y2Idx = x2Idx + nVerts;
int z2Idx = y2Idx + nVerts;
// Coordinates of two vertices (x1,y1,z1) & (x2,y2,z2)
double x1 = vertCoords(x1Idx);
double y1 = vertCoords(y1Idx);
double z1 = vertCoords(z1Idx);
double x2 = vertCoords(x2Idx);
double y2 = vertCoords(y2Idx);
double z2 = vertCoords(z2Idx);
// Edge length
double edgeLen = sqrt( pow(x2-x1, 2) + pow(y2-y1, 2) + pow(z2-z1, 2) );
// Compute function value = "edge length" - "reference edge length"
// 有一些存在len大于refLen的边，这不符合实际情况，因此要做constrained optimization
CPx(i) = edgeLen - refEdgeLens(i);
// if (edgeLen > refEdgeLens(i))
// {
// std::cout << "FOUND ONE" << std::endl;
// }
// Compute derivatives. Recall the derivative: sqrt'(x) = 1/(2*sqrt(x))
Jv(i, x1Idx) = (x1-x2) / edgeLen;
Jv(i, y1Idx) = (y1-y2) / edgeLen;
Jv(i, z1Idx) = (z1-z2) / edgeLen;
Jv(i, x2Idx) = (x2-x1) / edgeLen;
Jv(i, y2Idx) = (y2-y1) / edgeLen;
Jv(i, z2Idx) = (z2-z1) / edgeLen;
}
this->F = MPwAP * x;
this->C = CPx;
// Jacobian w.r.t actual variables using composition chain rule
// mat m1 = arma::join_cols(MPwAP, Jv * P);
//mat m2 = arma::join_rows(2*trans(MPwAP*x), 2 * trans(CPx));
this->J = MPwAP;
this->A = Jv * P;
//cout << this->J << endl;
vec CPxabs = arma::abs(CPx);
#if 0
cout << "Constraint function mean: " << arma::mean(CPxabs) << endl;
#endif
}
