private bool UpdateParticle(ref CCParticle p, float dt)
{
// life
p.timeToLive -= dt;
if (p.timeToLive > 0)
{
// Mode A: gravity, direction, tangential accel & radial accel
if (m_nEmitterMode == CCEmitterMode.Gravity)
{
float radial_x = 0;
float radial_y = 0;
float tmp_x, tmp_y;
float tangential_x, tangential_y;
float x = p.pos.X;
float y = p.pos.Y;
if (x != 0 || y != 0)
{
float l = 1.0f / (float)Math.Sqrt(x * x + y * y);
radial_x = x * l;
radial_y = y * l;
}
tangential_x = radial_x;
tangential_y = radial_y;
//radial = CCPoint.ccpMult(radial, p.modeA.radialAccel);
radial_x *= p.modeA.radialAccel;
radial_y *= p.modeA.radialAccel;
// tangential acceleration
float newy = tangential_x;
tangential_x = -tangential_y;
tangential_y = newy;
//tangential = CCPoint.ccpMult(tangential, p.modeA.tangentialAccel);
tangential_x *= p.modeA.tangentialAccel;
tangential_y *= p.modeA.tangentialAccel;
// (gravity + radial + tangential) * dt
//tmp = CCPoint.ccpAdd(CCPoint.ccpAdd(radial, tangential), modeA.gravity);
//tmp = CCPoint.ccpMult(tmp, dt);
//p.modeA.dir = CCPoint.ccpAdd(p.modeA.dir, tmp);
//tmp = CCPoint.ccpMult(p.modeA.dir, dt);
//p.pos = CCPoint.ccpAdd(p.pos, tmp);
tmp_x = (radial_x + tangential_x + modeA.gravity.X) * dt;
tmp_y = (radial_y + tangential_y + modeA.gravity.Y) * dt;
p.modeA.dir.X += tmp_x;
p.modeA.dir.Y += tmp_y;
p.pos.X += p.modeA.dir.X * dt;
p.pos.Y += p.modeA.dir.Y * dt;
}
// Mode B: radius movement
else
{
// Update the angle and radius of the particle.
p.modeB.angle += p.modeB.degreesPerSecond * dt;
p.modeB.radius += p.modeB.deltaRadius * dt;
p.pos.X = -CCMathHelper.Cos(p.modeB.angle) * p.modeB.radius;
p.pos.Y = -CCMathHelper.Sin(p.modeB.angle) * p.modeB.radius;
}
// color
p.color.R += (p.deltaColor.R * dt);
p.color.G += (p.deltaColor.G * dt);
p.color.B += (p.deltaColor.B * dt);
p.color.A += (p.deltaColor.A * dt);
// size
p.size += (p.deltaSize * dt);
if (p.size < 0)
{
p.size = 0;
}
// angle
p.rotation += (p.deltaRotation * dt);
return(true);
}
return(false);
}
private void UpdateQuad(ref CCV3F_C4B_T2F_Quad quad, ref CCParticle particle)
{
CCPoint newPosition;
if (m_ePositionType == CCPositionType.Free || m_ePositionType == CCPositionType.Relative)
{
newPosition.X = particle.pos.X - (s_currentPosition.X - particle.startPos.X);
newPosition.Y = particle.pos.Y - (s_currentPosition.Y - particle.startPos.Y);
}
else
{
newPosition = particle.pos;
}
// translate newPos to correct position, since matrix transform isn't performed in batchnode
// don't update the particle with the new position information, it will interfere with the radius and tangential calculations
if (m_pBatchNode != null)
{
newPosition.X += m_obPosition.X;
newPosition.Y += m_obPosition.Y;
}
CCColor4B color;
if (m_bOpacityModifyRGB)
{
color.R = (byte)(particle.color.R * particle.color.A * 255);
color.G = (byte)(particle.color.G * particle.color.A * 255);
color.B = (byte)(particle.color.B * particle.color.A * 255);
color.A = (byte)(particle.color.A * 255);
}
else
{
color.R = (byte)(particle.color.R * 255);
color.G = (byte)(particle.color.G * 255);
color.B = (byte)(particle.color.B * 255);
color.A = (byte)(particle.color.A * 255);
}
quad.BottomLeft.Colors = color;
quad.BottomRight.Colors = color;
quad.TopLeft.Colors = color;
quad.TopRight.Colors = color;
// vertices
float size_2 = particle.size / 2;
if (particle.rotation != 0.0)
{
float x1 = -size_2;
float y1 = -size_2;
float x2 = size_2;
float y2 = size_2;
float x = newPosition.X;
float y = newPosition.Y;
float r = -CCMathHelper.ToRadians(particle.rotation);
float cr = CCMathHelper.Cos(r);
float sr = CCMathHelper.Sin(r);
float ax = x1 * cr - y1 * sr + x;
float ay = x1 * sr + y1 * cr + y;
float bx = x2 * cr - y1 * sr + x;
float by = x2 * sr + y1 * cr + y;
float cx = x2 * cr - y2 * sr + x;
float cy = x2 * sr + y2 * cr + y;
float dx = x1 * cr - y2 * sr + x;
float dy = x1 * sr + y2 * cr + y;
// bottom-left
quad.BottomLeft.Vertices.X = ax;
quad.BottomLeft.Vertices.Y = ay;
// bottom-right vertex:
quad.BottomRight.Vertices.X = bx;
quad.BottomRight.Vertices.Y = by;
// top-left vertex:
quad.TopLeft.Vertices.X = dx;
quad.TopLeft.Vertices.Y = dy;
// top-right vertex:
quad.TopRight.Vertices.X = cx;
quad.TopRight.Vertices.Y = cy;
}
else
{
// bottom-left vertex:
quad.BottomLeft.Vertices.X = newPosition.X - size_2;
quad.BottomLeft.Vertices.Y = newPosition.Y - size_2;
// bottom-right vertex:
quad.BottomRight.Vertices.X = newPosition.X + size_2;
quad.BottomRight.Vertices.Y = newPosition.Y - size_2;
// top-left vertex:
quad.TopLeft.Vertices.X = newPosition.X - size_2;
quad.TopLeft.Vertices.Y = newPosition.Y + size_2;
// top-right vertex:
quad.TopRight.Vertices.X = newPosition.X + size_2;
quad.TopRight.Vertices.Y = newPosition.Y + size_2;
}
}
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());
}
}