internal static void InitEmitterCircleSource(EntityManager mgr, Entity emitter, DynamicBuffer <Particle> particles, int offset, Range speed, float randomizePos, float randomizeDir, float4x4 matrix, ref Random rand)
{
var radius = mgr.GetComponentData <EmitterCircleSource>(emitter).Radius;
for (var i = offset; i < particles.Length; i++)
{
var particle = particles[i];
float randomAngle = rand.NextFloat((float)-math.PI, (float)math.PI);
float radiusNormalized = math.sqrt(rand.Random01());
radius *= radiusNormalized;
var positionNormalized = new float3(math.sin(randomAngle), math.cos(randomAngle), 0.0f);
particle.position = GetParticlePosition(positionNormalized * radius, randomizePos, matrix, ref rand);
particle.velocity = GetParticleVelocity(ref positionNormalized, speed, randomizeDir, matrix, ref rand);
particle.rotation = GetParticleRotation(mgr, emitter, positionNormalized, ref rand);
particles[i] = particle;
}
}
internal static void InitEmitterSphereSource(EntityManager mgr, Entity emitter, DynamicBuffer <Particle> particles, int offset, float radius, bool hemisphere, Range speed, float randomizePos, float randomizeDir, float4x4 matrix, ref Random rand)
{
for (var i = offset; i < particles.Length; i++)
{
var particle = particles[i];
float3 positionOnUnitSphere = rand.NextFloat3Direction();
// For sphere, z ranges from [-1, 1]. For hemisphere, z ranges from [0, 1].
if (hemisphere)
{
positionOnUnitSphere.z = math.abs(positionOnUnitSphere.z);
}
// Create more points toward the outer part of the sphere
float3 position = positionOnUnitSphere * math.pow(rand.Random01(), 1.0f / 3.0f) * radius;
particle.position = GetParticlePosition(position, randomizePos, matrix, ref rand);
particle.velocity = GetParticleVelocity(ref positionOnUnitSphere, speed, randomizeDir, matrix, ref rand);
particle.rotation = GetParticleRotation(mgr, emitter, positionOnUnitSphere, ref rand);
particles[i] = particle;
}
}
internal static void InitEmitterRectangleSource(EntityManager mgr, Entity emitter, DynamicBuffer <Particle> particles, int offset, Range speed, float randomizePos, float randomizeDir, float4x4 matrix, ref Random rand)
{
// Unit rectangle centered at the origin
float2 bottomLeft = new float2(-0.5f, -0.5f);
float2 topRight = new float2(0.5f, 0.5f);
float3 direction = new float3(0, 0, 1);
for (var i = offset; i < particles.Length; i++)
{
var particle = particles[i];
var position = new float3(rand.NextFloat2(bottomLeft, topRight), 0.0f);
particle.position = GetParticlePosition(position, randomizePos, matrix, ref rand);
particle.velocity = GetParticleVelocity(ref direction, speed, randomizeDir, matrix, ref rand);
particle.rotation = GetParticleRotation(mgr, emitter, direction, ref rand);
particles[i] = particle;
}
}
internal static void InitEmitterConeSource(EntityManager mgr, Entity emitter, DynamicBuffer <Particle> particles, int offset, Range speed, float randomizePos, float randomizeDir, float4x4 matrix, ref Random rand)
{
var source = mgr.GetComponentData <EmitterConeSource>(emitter);
source.Angle = math.clamp(source.Angle, 0.0f, 90.0f);
float coneAngle = math.radians(source.Angle);
for (var i = offset; i < particles.Length; i++)
{
var particle = particles[i];
float angle = rand.Random01() * 2.0f * math.PI;
float radiusNormalized = math.sqrt(rand.Random01());
float3 localPositionOnConeBase;
localPositionOnConeBase.x = math.cos(angle);
localPositionOnConeBase.y = math.sin(angle);
localPositionOnConeBase.z = 0.0f;
localPositionOnConeBase *= radiusNormalized;
particle.position = GetParticlePosition(localPositionOnConeBase * source.Radius, randomizePos, matrix, ref rand);
float directionRadius = math.sin(coneAngle);
float directionHeight = math.cos(coneAngle);
float3 direction = new float3(localPositionOnConeBase.x * directionRadius, localPositionOnConeBase.y * directionRadius, directionHeight);
particle.velocity = GetParticleVelocity(ref direction, speed, randomizeDir, matrix, ref rand);
particle.rotation = GetParticleRotation(mgr, emitter, direction, ref rand);
particles[i] = particle;
}
}
