Question oapi.get_levelref Not Recognizing Particle Stream Handle?

[Thunder Chicken]

I created particle streams to mimic the wake and bow wave from my boat. They were working, and I could vary the intensity, but for some reason the code is now throwing errors.

I establish the particle streams and establish their intensities with this code, called within clbk_setclasscaps:

function make_pretty.particle_streams()

    wake_particle_spec =
    {
        flags = 0,
        srcsize = 0.5,
        srcrate = 10,
        v0 = 0,
        srcspread = 0.25,
        lifetime = 2.0,
        growthrate = 0,
        atmslowdown = 2.0,
        ltype = PARTICLE.DIFFUSE,
        levelmap = PARTICLE.LVL_PSQRT,
        lmin = 0,
        lmax = 2,
        atmsmap = PARTICLE.ATM_PLOG,
        amin = 1e-4,
        amax = 1,
        tex = 0
    }

    bow_wave_particle_spec =
    {
        flags = 0,
        srcsize = 0.5,
        srcrate = 20,
        v0 = 1,
        srcspread = 0.1,
        lifetime = 1.0,
        growthrate = 0,
        atmslowdown = 0.0,
        ltype = PARTICLE.DIFFUSE,
        levelmap = PARTICLE.LVL_PSQRT,
        lmin = 0,
        lmax = 2,
        atmsmap = PARTICLE.ATM_PLOG,
        amin = 1e-4,
        amax = 1,
        tex = 0
    }

    wake_level = 1
    bow_level = 1

    wake = {}

    wake[1] = vi:add_particlestream(wake_particle_spec, vec.add(rudder_pivot, {x=0, y=0, z=-0.5}), {x=0, y=0, z=-1}, wake_level)
    wake[2] = vi:add_particlestream(wake_particle_spec, vec.add(rudder_pivot, {x=-0.35, y=0, z=-0.5}), {x=0, y=0, z=-1}, wake_level)
    wake[3] = vi:add_particlestream(wake_particle_spec, vec.add(rudder_pivot, {x=-0.7, y=0, z=-0.5}), {x=0, y=0, z=-1}, wake_level)
    wake[4] = vi:add_particlestream(wake_particle_spec, vec.add(rudder_pivot, {x=0.35, y=0, z=-0.5}), {x=0, y=0, z=-1}, wake_level)
    wake[5] = vi:add_particlestream(wake_particle_spec, vec.add(rudder_pivot, {x=0.7, y=0, z=-0.5}), {x=0, y=0, z=-1}, wake_level)

    bow_wave = {}

    bow_wave[1] = vi:add_particlestream(bow_wave_particle_spec, vec.add(rudder_pivot, {x=0, y=0, z=5.2}), {x=10, y=0, z=0}, bow_level)
    bow_wave[2] = vi:add_particlestream(bow_wave_particle_spec, vec.add(rudder_pivot, {x=0, y=0, z=5.2}), {x=-10, y=0, z=0}, bow_level)

    wake_intensity = {}

    for i = 1, #wake do

        if wake ~= nil then

            wake_intensity[i] = oapi.particle_getlevelref(wake[i])

        end

    end

    bow_wave_intensity = {}

    for i = 1, #bow_wave do

        if bow_wave[i] ~= nil then

            bow_wave_intensity[i] = oapi.particle_getlevelref(bow_wave[i])

        end

    end

end

Both instances of oapi.particle_getlevelref cause errors (from Orbiter.log): oapi_particle_getlevelref: Argument 1: invalid object. I am again stumped, as I define the particle streams before these calls in the same block! I get no other errors in Orbiter.log set to verbose.

 

[Gondos]

I created particle streams to mimic the wake and bow wave from my boat. They were working, and I could vary the intensity, but for some reason the code is now throwing errors.

I establish the particle streams and establish their intensities with this code, called within clbk_setclasscaps:

function make_pretty.particle_streams()

    wake_particle_spec =
    {
        flags = 0,
        srcsize = 0.5,
        srcrate = 10,
        v0 = 0,
        srcspread = 0.25,
        lifetime = 2.0,
        growthrate = 0,
        atmslowdown = 2.0,
        ltype = PARTICLE.DIFFUSE,
        levelmap = PARTICLE.LVL_PSQRT,
        lmin = 0,
        lmax = 2,
        atmsmap = PARTICLE.ATM_PLOG,
        amin = 1e-4,
        amax = 1,
        tex = 0
    }

    bow_wave_particle_spec =
    {
        flags = 0,
        srcsize = 0.5,
        srcrate = 20,
        v0 = 1,
        srcspread = 0.1,
        lifetime = 1.0,
        growthrate = 0,
        atmslowdown = 0.0,
        ltype = PARTICLE.DIFFUSE,
        levelmap = PARTICLE.LVL_PSQRT,
        lmin = 0,
        lmax = 2,
        atmsmap = PARTICLE.ATM_PLOG,
        amin = 1e-4,
        amax = 1,
        tex = 0
    }

    wake_level = 1
    bow_level = 1

    wake = {}

    wake[1] = vi:add_particlestream(wake_particle_spec, vec.add(rudder_pivot, {x=0, y=0, z=-0.5}), {x=0, y=0, z=-1}, wake_level)
    wake[2] = vi:add_particlestream(wake_particle_spec, vec.add(rudder_pivot, {x=-0.35, y=0, z=-0.5}), {x=0, y=0, z=-1}, wake_level)
    wake[3] = vi:add_particlestream(wake_particle_spec, vec.add(rudder_pivot, {x=-0.7, y=0, z=-0.5}), {x=0, y=0, z=-1}, wake_level)
    wake[4] = vi:add_particlestream(wake_particle_spec, vec.add(rudder_pivot, {x=0.35, y=0, z=-0.5}), {x=0, y=0, z=-1}, wake_level)
    wake[5] = vi:add_particlestream(wake_particle_spec, vec.add(rudder_pivot, {x=0.7, y=0, z=-0.5}), {x=0, y=0, z=-1}, wake_level)

    bow_wave = {}

    bow_wave[1] = vi:add_particlestream(bow_wave_particle_spec, vec.add(rudder_pivot, {x=0, y=0, z=5.2}), {x=10, y=0, z=0}, bow_level)
    bow_wave[2] = vi:add_particlestream(bow_wave_particle_spec, vec.add(rudder_pivot, {x=0, y=0, z=5.2}), {x=-10, y=0, z=0}, bow_level)

    wake_intensity = {}

    for i = 1, #wake do

        if wake ~= nil then

            wake_intensity[i] = oapi.particle_getlevelref(wake[i])

        end

    end

    bow_wave_intensity = {}

    for i = 1, #bow_wave do

        if bow_wave[i] ~= nil then

            bow_wave_intensity[i] = oapi.particle_getlevelref(bow_wave[i])

        end

    end

end

Both instances of oapi.particle_getlevelref cause errors (from Orbiter.log): oapi_particle_getlevelref: Argument 1: invalid object. I am again stumped, as I define the particle streams before these calls in the same block! I get no other errors in Orbiter.log set to verbose.

It can do that if vi:add_particlestream fails.
Is the oapi_particle_getlevelref error the first one in the logs?
Just in case: vi:add_particlestream can fail if you're using the inline GC (or console mode?) of if you disabled particle streams in the visual settings.
Edit: vi:add_particlestream actually returns 2 values, the stream handle and the levelref (not sure if it's working properly) so you can get them both in one go, no need for 2 for loops.

 

[Thunder Chicken]

It can do that if vi:add_particlestream fails.
Is the oapi_particle_getlevelref error the first one in the logs?

It's the only error.

Just in case: vi:add_particlestream can fail if you're using the inline GC (or console mode?) of if you disabled particle streams in the visual settings.

Oh, for crying out loud ...that was the problem. Particle streams were not enabled. Particles work fine again.

How can I check if particle streams are enabled so I can protect against this?

Edit: vi:add_particlestream actually returns 2 values, the stream handle and the levelref (not sure if it's working properly) so you can get them both in one go, no need for 2 for loops.

My code works again, but if I can consolidate code I'd like to try.

Would this be the correct usage?:

particle_handle, level_ref = vi:add_particlestream(...)

 

[Gondos]

How can I check if particle streams are enabled so I can protect against this?

I don't think you can directly (even in C++). I'll see if I can make the vi:add_particlestream call return nil instead of a bogus userdata so that you can at least see that the call failed.

Would this be the correct usage?:


particle_handle, level_ref = vi:add_particlestream(...)

Yes that should be it.

 

[Gondos]

The PR is ready.