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Support backwards play, a requirement for scrubbing

Browse Source 
Uncomment the line at the top of ControlToolBar::PlayPlayRegion to play
everything backwards and test it

It even works correctly with a time track
This commit is contained in:
Paul-Licameli
2015-04-16 17:35:58 -04:00
parent 2b85d0edb4
commit 5abfd25a34
8 changed files with 256 additions and 109 deletions
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92
src/Envelope.cpp
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@@ -1430,31 +1430,42 @@ double Envelope::SolveIntegralOfInverse( double t0, double area )
{
if(area == 0.0)
return t0;
if(area < 0.0)
{
fprintf( stderr, "SolveIntegralOfInverse called with negative area, this is not supported!\n" );
return t0;
}
unsigned int count = mEnv.Count();
if(count == 0) // 'empty' envelope
return t0 + area * mDefaultValue;
double lastT, lastVal;
unsigned int i; // this is the next point to check
int i; // this is the next point to check
if(t0 < mEnv[0]->GetT()) // t0 preceding the first point
{
i = 1;
lastT = mEnv[0]->GetT();
lastVal = mEnv[0]->GetVal();
double added = (lastT - t0) / lastVal;
if(added >= area)
if (area < 0) {
return t0 + area * mEnv[0]->GetVal();
area -= added;
}
else {
i = 1;
lastT = mEnv[0]->GetT();
lastVal = mEnv[0]->GetVal();
double added = (lastT - t0) / lastVal;
if(added >= area)
return t0 + area * mEnv[0]->GetVal();
area -= added;
}
}
else if(t0 >= mEnv[count - 1]->GetT()) // t0 following the last point
{
return t0 + area * mEnv[count - 1]->GetVal();
if (area < 0) {
i = count - 2;
lastT = mEnv[count - 1]->GetT();
lastVal = mEnv[count - 1]->GetVal();
double added = (lastT - t0) / lastVal; // negative
if(added <= area)
return t0 + area * mEnv[count - 1]->GetVal();
area -= added;
}
else {
return t0 + area * mEnv[count - 1]->GetVal();
}
}
else // t0 enclosed by points
{
@@ -1463,25 +1474,52 @@ double Envelope::SolveIntegralOfInverse( double t0, double area )
BinarySearchForTime(lo, hi, t0);
lastVal = InterpolatePoints(mEnv[lo]->GetVal(), mEnv[hi]->GetVal(), (t0 - mEnv[lo]->GetT()) / (mEnv[hi]->GetT() - mEnv[lo]->GetT()), mDB);
lastT = t0;
i = hi; // the point immediately after t0.
if (area < 0)
i = lo;
else
i = hi; // the point immediately after t0.
}
// loop through the rest of the envelope points until we get to t1
while (1)
{
if(i >= count) // the requested range extends beyond the last point
if (area < 0) {
// loop BACKWARDS through the rest of the envelope points until we get to t1
// (which is less than t0)
while (1)
{
return lastT + area * lastVal;
if(i < 0) // the requested range extends beyond the leftmost point
{
return lastT + area * lastVal;
}
else
{
double added =
-IntegrateInverseInterpolated(mEnv[i]->GetVal(), lastVal, lastT - mEnv[i]->GetT(), mDB);
if(added <= area)
return lastT - SolveIntegrateInverseInterpolated(lastVal, mEnv[i]->GetVal(), lastT - mEnv[i]->GetT(), -area, mDB);
area -= added;
lastT = mEnv[i]->GetT();
lastVal = mEnv[i]->GetVal();
--i;
}
}
else
}
else {
// loop through the rest of the envelope points until we get to t1
while (1)
{
double added = IntegrateInverseInterpolated(lastVal, mEnv[i]->GetVal(), mEnv[i]->GetT() - lastT, mDB);
if(added >= area)
return lastT + SolveIntegrateInverseInterpolated(lastVal, mEnv[i]->GetVal(), mEnv[i]->GetT() - lastT, area, mDB);
area -= added;
lastT = mEnv[i]->GetT();
lastVal = mEnv[i]->GetVal();
i++;
if(i >= count) // the requested range extends beyond the last point
{
return lastT + area * lastVal;
}
else
{
double added = IntegrateInverseInterpolated(lastVal, mEnv[i]->GetVal(), mEnv[i]->GetT() - lastT, mDB);
if(added >= area)
return lastT + SolveIntegrateInverseInterpolated(lastVal, mEnv[i]->GetVal(), mEnv[i]->GetT() - lastT, area, mDB);
area -= added;
lastT = mEnv[i]->GetT();
lastVal = mEnv[i]->GetVal();
i++;
}
}
}
}