/// <summary>
/// This function will be called whenever a particle is colliding.
/// </summary>
/// <param name="particle">The collided particle.</param>
void OnParticleCollisionEvent(PlaygroundEventParticle particle)
{
if (createPointsOnCollision)
{
int trailIndex = GetNewestTrailWithParticleId(particle.particleId);
if (trailIndex < 0)
{
return;
}
ParticlePlaygroundTrail trailAtIndex = _trails[trailIndex];
trailAtIndex.AddPoint(playgroundSystem.particleCache[particle.particleId].position, EvaluateWidth(0), time, _calculationStartTime);
}
}
/****************************************************************************
* Internal
****************************************************************************/
void CalculateTrail()
{
// Iterate through all trails
for (int i = 0; i < _trails.Count; i++)
{
ParticlePlaygroundTrail trail = _trails[i];
// Skip this trail if it's prepared to be removed
if (trail.CanRemoveTrail())
{
continue;
}
if (trail.particleId >= 0 && !trail.IsDead())
{
if (trail.GetBirthIterator() > 0)
{
// New point creation
float pointDistance = Vector3.Distance(trail.GetParticlePosition(), trail.GetLastAddedPointPosition());
if (pointDistance > minVertexDistance)
{
float pathDeviationAngle = trail.GetPathDeviation();
if (pointDistance > maxVertexDistance || pathDeviationAngle > maxPathDeviation)
{
trail.AddPoint(playgroundSystem.particleCache[trail.particleId].position, EvaluateWidth(0), time, _calculationStartTime);
}
}
}
else
{
// First point creation
trail.SetFirstPoint(playgroundSystem.particleCache[trail.particleId].position, playgroundSystem.particleCache[trail.particleId].velocity, EvaluateWidth(0), time, _calculationStartTime);
}
// Set the particle position info
trail.SetParticlePosition(playgroundSystem.particleCache[trail.particleId].position);
}
// Update the trail points
for (int x = 0; x < trail.trailPoints.Count; x++)
{
TrailPoint trailPoint = trail.trailPoints[x];
if (trailPoint.CanRemove())
{
trail.RemovePoint(x);
if (!_localSpace)
{
continue;
}
}
float normalizedLifetime = trailPoint.GetNormalizedLifetime();
// Update trail points data
trailPoint.Update(
_calculationStartTime,
EvaluateWidth(normalizedLifetime)
);
// Set end point to follow particle
if (!trail.IsDead() && x == trail.trailPoints.Count - 1)
{
trailPoint.position = trail.GetParticlePosition();
}
// Rotation of trail points
Vector3 currentPosition = trailPoint.position;
Vector3 nextPosition = x < trail.trailPoints.Count - 1? trail.trailPoints[x + 1].position : currentPosition + (currentPosition - trail.trailPoints[x - 1].position);
Vector3 lookDirection = Vector3.up;
switch (renderMode)
{
case TrailRenderMode.Vertical:
lookDirection = Vector3.forward;
break;
case TrailRenderMode.Billboard:
lookDirection = (_billboardTransformPosition - currentPosition).normalized;
break;
}
// If this is local space then recompute current & next position based on the local matrix
if (_localSpace)
{
currentPosition = _localMatrix.MultiplyPoint3x4(currentPosition);
nextPosition = _localMatrix.MultiplyPoint3x4(nextPosition);
}
Vector3 dir = renderMode != TrailRenderMode.CustomRenderScale? (Vector3.Cross(lookDirection, nextPosition - currentPosition)).normalized : customRenderScale;
Vector3 lPoint = currentPosition + (dir * (trailPoint.width * .5f));
Vector3 rPoint = currentPosition - (dir * (trailPoint.width * .5f));
// Set mesh vertices into the rotated position
trail.meshVerticesCache[x * 2] = lPoint;
trail.meshVerticesCache[(x * 2) + 1] = rPoint;
// Set uv
float uvRatio = uvMode == TrailUvMode.Lifetime? normalizedLifetime : (x * 1f) / (trail.GetBirthIterator() - 1);
trail.meshUvsCache[x * 2] = new Vector2(uvRatio, 0);
trail.meshUvsCache[(x * 2) + 1] = new Vector2(uvRatio, 1f);
// Update colors
if (colorMode == TrailColorMode.Lifetime)
{
Color32 color = EvaluateColor(normalizedLifetime);
color.a = (byte)(color.a * (pointArrayAlpha.Evaluate((x * 1f) / (trail.GetBirthIterator() - 1))));
trail.SetColor(x, color);
}
else
{
trail.SetColor(x, EvaluateColor(i, x));
}
}
}
}