Why do particles created on objects face sideways?

Questions & Answers
1

Whenever I add a particle system to a mesh, the emitter is always facing sideways/perpendicular to the mesh y/up axis. my mesh has no rotation; normals are facing out, and y is up, but conic and hemispherical particles are created sideways, and you can’t rotate them without rotating the object itself. i can make the mesh-shape the emitter, but i don’t always want to do that.

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EDIT:

Thanks for the answers, however the startRotation does not affect the emitter direction, and yes, adding a parent object to rotate the particles is a work-around, but in that case i can just add a particle emitter as a child of the object itself. but neither of those explains why it begins sideways instead of normally with y-up

2

Why not add the particle component to an empty gameobject and make that a child of the object? Then you can rotate the particles however you wish without affecting the parent.

3

You can set the initial rotation of particles by particleSystem.startRotation.