BDF2 integrator in HLSL

BDF2_integrate_HLSL.txt

void BFD2(inout ParticleSimulationData Particle, float3 Accel)
{
	float3 x = Particle.Position;
	float3 v = Particle.Velocity;

	float3 x1 = Particle.PositionPrev;
	float3 v1 = Particle.VelocityPrev;

	Particle.Position = (4.0/3.0) * x - (1.0/3.0) * x1 + 1.0 * ((8.0/9.0) * v - (2.0/9.0) * v1 + (4.0/9.0) * TimeStep2 * Accel);
	Particle.PositionPrev = x;
}

void BDF2VelocityUpdate(inout ParticleSimulationData Particle)
{
	Particle.Velocity = (3.0/2.0) * Particle.Position - 2.0 * Particle.PositionPrev + 0.5 * Particle.PositionPrev2;
}