private void InitParticle(ref CCParticle particle)
{
// timeToLive
// no negative life. prevent division by 0
particle.timeToLive = Math.Max(0, m_fLife + m_fLifeVar * CCRandom.Float_Minus1_1());
// position
particle.pos.X = m_tSourcePosition.X + m_tPosVar.X * CCRandom.Float_Minus1_1();
particle.pos.Y = m_tSourcePosition.Y + m_tPosVar.Y * CCRandom.Float_Minus1_1();
// Color
CCColor4F start;
start.R = MathHelper.Clamp(m_tStartColor.R + m_tStartColorVar.R * CCRandom.Float_Minus1_1(), 0, 1);
start.G = MathHelper.Clamp(m_tStartColor.G + m_tStartColorVar.G * CCRandom.Float_Minus1_1(), 0, 1);
start.B = MathHelper.Clamp(m_tStartColor.B + m_tStartColorVar.B * CCRandom.Float_Minus1_1(), 0, 1);
start.A = MathHelper.Clamp(m_tStartColor.A + m_tStartColorVar.A * CCRandom.Float_Minus1_1(), 0, 1);
CCColor4F end;
end.R = MathHelper.Clamp(m_tEndColor.R + m_tEndColorVar.R * CCRandom.Float_Minus1_1(), 0, 1);
end.G = MathHelper.Clamp(m_tEndColor.G + m_tEndColorVar.G * CCRandom.Float_Minus1_1(), 0, 1);
end.B = MathHelper.Clamp(m_tEndColor.B + m_tEndColorVar.B * CCRandom.Float_Minus1_1(), 0, 1);
end.A = MathHelper.Clamp(m_tEndColor.A + m_tEndColorVar.A * CCRandom.Float_Minus1_1(), 0, 1);
particle.color = start;
particle.deltaColor.R = (end.R - start.R) / particle.timeToLive;
particle.deltaColor.G = (end.G - start.G) / particle.timeToLive;
particle.deltaColor.B = (end.B - start.B) / particle.timeToLive;
particle.deltaColor.A = (end.A - start.A) / particle.timeToLive;
// size
float startS = m_fStartSize + m_fStartSizeVar * CCRandom.Float_Minus1_1();
startS = Math.Max(0, startS); // No negative value
particle.size = startS;
if (m_fEndSize == kCCParticleStartSizeEqualToEndSize)
{
particle.deltaSize = 0;
}
else
{
float endS = m_fEndSize + m_fEndSizeVar * CCRandom.Float_Minus1_1();
endS = Math.Max(0, endS); // No negative values
particle.deltaSize = (endS - startS) / particle.timeToLive;
}
// rotation
float startA = m_fStartSpin + m_fStartSpinVar * CCRandom.Float_Minus1_1();
float endA = m_fEndSpin + m_fEndSpinVar * CCRandom.Float_Minus1_1();
particle.rotation = startA;
particle.deltaRotation = (endA - startA) / particle.timeToLive;
// position
if (m_ePositionType == CCPositionType.Free)
{
particle.startPos = ConvertToWorldSpace(CCPoint.Zero);
}
else if (m_ePositionType == CCPositionType.Relative)
{
particle.startPos = m_obPosition;
}
// direction
float a = MathHelper.ToRadians(m_fAngle + m_fAngleVar * CCRandom.Float_Minus1_1());
// Mode Gravity: A
if (m_nEmitterMode == CCEmitterMode.Gravity)
{
var v = new CCPoint(CCMathHelper.Cos(a), CCMathHelper.Sin(a));
float s = modeA.speed + modeA.speedVar * CCRandom.Float_Minus1_1();
// direction
particle.modeA.dir = v * s;
// radial accel
particle.modeA.radialAccel = modeA.radialAccel + modeA.radialAccelVar * CCRandom.Float_Minus1_1();
// tangential accel
particle.modeA.tangentialAccel = modeA.tangentialAccel + modeA.tangentialAccelVar * CCRandom.Float_Minus1_1();
// rotation is dir
if (modeA.rotationIsDir)
{
particle.rotation = -MathHelper.ToDegrees(CCPoint.ToAngle(particle.modeA.dir));
}
}
// Mode Radius: B
else
{
// Set the default diameter of the particle from the source position
float startRadius = modeB.startRadius + modeB.startRadiusVar * CCRandom.Float_Minus1_1();
float endRadius = modeB.endRadius + modeB.endRadiusVar * CCRandom.Float_Minus1_1();
particle.modeB.radius = startRadius;
if (modeB.endRadius == kCCParticleStartRadiusEqualToEndRadius)
{
particle.modeB.deltaRadius = 0;
}
else
{
particle.modeB.deltaRadius = (endRadius - startRadius) / particle.timeToLive;
}
particle.modeB.angle = a;
particle.modeB.degreesPerSecond =
MathHelper.ToRadians(modeB.rotatePerSecond + modeB.rotatePerSecondVar * CCRandom.Float_Minus1_1());
}
}
