Help with engines?

[SmashingKirby148]

Hello! I wanted to make part mods for a long time. Just to take a break from planet mods. But I can't find any tutorials on engines. The only tutorial I found was on fuel tanks. I got modelling down, but textures and all of that stuff (especially coding) just gets me. Any experienced part makers have a good tutorial for me? Thanks!

[NecroBones]

There are several links here:

http://forum.kerbalspaceprogram.com/threads/94638-Mod-Development-Links-Compilation-START-HERE

That should help get you started.

[SmashingKirby148]

There are several links here:

http://forum.kerbalspaceprogram.com/threads/94638-Mod-Development-Links-Compilation-START-HERE

That should help get you started.

These didn't really have exactly what I was looking for.

Edited June 20, 2015 by SmashingKirby148

[Randazzo]

What modeling software are you using? Do you know how to UV map your models?

The only code you'll have to write for an engine is a config file, unless you intend to write a plug-in, and cfgs are easy enough to get the hang of. Just take a peek at the existing engines setups and figure out what you want to change. But... here.

PART
{
    name = VADULE
    module = Part
    author = Randazzo
    MODEL                                 /// <-- this makes something unreadable to the game, so you can type stuff after it. You can do a lot with the MODEL node, like reference textures from another place, but you can also just use mesh = model.mu
    {
        model = VanguardAstrodynamics/engines/VADULE/model
        scale = 1.25,1,1.25
    }
    scale = 1
    rescaleFactor = 1                /// This will default to 1.25, which is fine if your model is a 1 meter scale model and needs to be scaled up.
    node_stack_top = 0.0, 0.012, 0.0, 0.0, 1.0, 0.0, 1 
    node_stack_bottom = 0.0, -0.352, 0.0, 0.0, -1.0, 0.0, 0   // The attachment node definitions. The first six are coordinates. The last one is the visual node size (0,1,2,3) and must be an integer. No 0.5 or anything like that.
    node_attach = 0.0, 0.012, 0.0, 0.0, 1.0, 0.0, 1
    fx_exhaustFlame_blue_small = 0.0, -0.137, 0.0, 0.0, 1.0, 0.0, running
    fx_exhaustLight_blue = 0.0, -0.137, 0.0, 0.0, 0.0, 1.0, running
    fx_smokeTrail_light = 0.0, -0.137, 0.0, 0.0, 1.0, 0.0, running
    sound_vent_medium = engage
    sound_rocket_hard = running
    sound_vent_soft = disengage
    sound_explosion_low = flameout
    TechRequired = advRocketry
    entryCost = 1600
    cost = 390
    category = Engine
    subcategory = 0
    title = VAD Ultra-Light Engine
    manufacturer = Vanguard Astrodynamics
    description = Designed to serve primarily as a landing engine, the VADULE is remarkably light yet powerful. However, as a result of it's lightweight design, it is somewhat more fragile than it's contemporaries.
    attachRules = 1,1,1,0,0   /// Attachment rules. Stack, srfAttach, allowStack, allowSrfAttach, allowCollision. 1 is yes, 0 is no.
    mass = 0.15
    // heatConductivity = 0.06 // half default
    emissiveConstant = 0.8 // engine nozzles are good at radiating.
    dragModelType = default
    maximum_drag = 0.2
    minimum_drag = 0.2
    angularDrag = 2
    crashTolerance = 4
    maxTemp = 2000 // = 3600
    bulkheadProfiles = size1
    MODULE
    {
        name = ModuleEngines
        thrustVectorTransformName = thrustTransform  // thrustTransform can be named something else, it is the node in your model that denotes the thrust direction.
        exhaustDamage = True
        ignitionThreshold = 0.1
        minThrust = 0
        maxThrust = 40  
        heatProduction = 150
        fxOffset = 0, 0, 0.21
        EngineType = LiquidFuel
        PROPELLANT
        {
            name = LiquidFuel
            ratio = 0.9
            DrawGauge = True
        }
        PROPELLANT
        {
            name = Oxidizer
            ratio = 1.1
        }
        atmosphereCurve
        {
            key = 0 365  // These set your ISP curve. 1 = Sea Level on Kerbin or 1 atm. 0 is vacuum, and the bottom one defines at what pressure your engine has zero thrust for a proper curve. 
            key = 1 85
            key = 5 0.001
        }
    }
    MODULE
    {
        name = ModuleGimbal   // If you have a gimbaling node, this is where you put it. 
        gimbalTransformName = nozzle
        gimbalRange = 4
    }
    MODULE
    {
        name = ModuleAnimateHeat
        ThermalAnim = heatanim  // If you added an emissive animation, this is where you put it.
    }
    MODULE
    {
        name = ModuleAlternator
        RESOURCE
        {
            name = ElectricCharge
            rate = 2.0
        }
    }
    RESOURCE
    {
        name = ElectricCharge
        amount = 0
        maxAmount = 0
        isTweakable = false
        hideFlow = true
    }
    MODULE
    {
        name = ModuleTestSubject  // Including this will allow your engine to show up in contracts
        environments = 15
        useStaging = True
        useEvent = False
    }
    MODULE
    {
        name = ModuleSurfaceFX  // ground smoke
        thrustProviderModuleIndex = 0
        fxMax = 0.3
        maxDistance = 30
        falloff = 1.7
        thrustTransformName = thrustTransform
    }
}

This is important: Make sure your thrustTransform (or whatever you call it) local Z axis is pointing down in Blender. You can switch from local to global by pressing alt+space and selecting local.

Edited June 20, 2015 by Randazzo

[SmashingKirby148]

What modeling software are you using? Do you know how to UV map your models?

The only code you'll have to write for an engine is a config file, unless you intend to write a plug-in, and cfgs are easy enough to get the hang of. Just take a peek at the existing engines setups and figure out what you want to change. But... here.

PART
{
    name = VADULE
    module = Part
    author = Randazzo
    MODEL                                 /// <-- this makes something unreadable to the game, so you can type stuff after it. You can do a lot with the MODEL node, like reference textures from another place, but you can also just use mesh = model.mu
    {
        model = VanguardAstrodynamics/engines/VADULE/model
        scale = 1.25,1,1.25
    }
    scale = 1
    rescaleFactor = 1                /// This will default to 1.25, which is fine if your model is a 1 meter scale model and needs to be scaled up.
    node_stack_top = 0.0, 0.012, 0.0, 0.0, 1.0, 0.0, 1 
    node_stack_bottom = 0.0, -0.352, 0.0, 0.0, -1.0, 0.0, 0   // The attachment node definitions. The first six are coordinates. The last one is the visual node size (0,1,2,3) and must be an integer. No 0.5 or anything like that.
    node_attach = 0.0, 0.012, 0.0, 0.0, 1.0, 0.0, 1
    fx_exhaustFlame_blue_small = 0.0, -0.137, 0.0, 0.0, 1.0, 0.0, running
    fx_exhaustLight_blue = 0.0, -0.137, 0.0, 0.0, 0.0, 1.0, running
    fx_smokeTrail_light = 0.0, -0.137, 0.0, 0.0, 1.0, 0.0, running
    sound_vent_medium = engage
    sound_rocket_hard = running
    sound_vent_soft = disengage
    sound_explosion_low = flameout
    TechRequired = advRocketry
    entryCost = 1600
    cost = 390
    category = Engine
    subcategory = 0
    title = VAD Ultra-Light Engine
    manufacturer = Vanguard Astrodynamics
    description = Designed to serve primarily as a landing engine, the VADULE is remarkably light yet powerful. However, as a result of it's lightweight design, it is somewhat more fragile than it's contemporaries.
    attachRules = 1,1,1,0,0   /// Attachment rules. Stack, srfAttach, allowStack, allowSrfAttach, allowCollision. 1 is yes, 0 is no.
    mass = 0.15
    // heatConductivity = 0.06 // half default
    emissiveConstant = 0.8 // engine nozzles are good at radiating.
    dragModelType = default
    maximum_drag = 0.2
    minimum_drag = 0.2
    angularDrag = 2
    crashTolerance = 4
    maxTemp = 2000 // = 3600
    bulkheadProfiles = size1
    MODULE
    {
        name = ModuleEngines
        thrustVectorTransformName = thrustTransform  // thrustTransform can be named something else, it is the node in your model that denotes the thrust direction.
        exhaustDamage = True
        ignitionThreshold = 0.1
        minThrust = 0
        maxThrust = 40  
        heatProduction = 150
        fxOffset = 0, 0, 0.21
        EngineType = LiquidFuel
        PROPELLANT
        {
            name = LiquidFuel
            ratio = 0.9
            DrawGauge = True
        }
        PROPELLANT
        {
            name = Oxidizer
            ratio = 1.1
        }
        atmosphereCurve
        {
            key = 0 365  // These set your ISP curve. 1 = Sea Level on Kerbin or 1 atm. 0 is vacuum, and the bottom one defines at what pressure your engine has zero thrust for a proper curve. 
            key = 1 85
            key = 5 0.001
        }
    }
    MODULE
    {
        name = ModuleGimbal   // If you have a gimbaling node, this is where you put it. 
        gimbalTransformName = nozzle
        gimbalRange = 4
    }
    MODULE
    {
        name = ModuleAnimateHeat
        ThermalAnim = heatanim  // If you added an emissive animation, this is where you put it.
    }
    MODULE
    {
        name = ModuleAlternator
        RESOURCE
        {
            name = ElectricCharge
            rate = 2.0
        }
    }
    RESOURCE
    {
        name = ElectricCharge
        amount = 0
        maxAmount = 0
        isTweakable = false
        hideFlow = true
    }
    MODULE
    {
        name = ModuleTestSubject  // Including this will allow your engine to show up in contracts
        environments = 15
        useStaging = True
        useEvent = False
    }
    MODULE
    {
        name = ModuleSurfaceFX  // ground smoke
        thrustProviderModuleIndex = 0
        fxMax = 0.3
        maxDistance = 30
        falloff = 1.7
        thrustTransformName = thrustTransform
    }
}

This is important: Make sure your thrustTransform (or whatever you call it) local Z axis is pointing down in Blender. You can switch from local to global by pressing alt+space and selecting local.

http://i.imgur.com/hHhFCPUh.png

I got the model sorted out. And the texture.

And thanks as well!

- - - Updated - - -

I can't get the Blue arrow to go down

[sumghai]

I can't get the Blue arrow to go down

You do that in Unity, not Blender.

[SmashingKirby148]

You do that in Unity, not Blender.

Oh, ok. Thanks.

[Randazzo]

You do that in Unity, not Blender.

I've always done it in Blender, is it easier in Unity? Serious question.

Don't the pre-fab connections get messed up if you do it that way? Does that even matter?

[SmashingKirby148]

Ok, so I got Unity, and it's stuck at the connecting bit...

[Randazzo]

Ok, so I got Unity, and it's stuck at the connecting bit...

http://i.imgur.com/R8uwR2F.png

Good. Cease and desist, and get unity 4.2.2

[SmashingKirby148]

Good. Cease and desist, and get unity 4.2.2

Oh, alright.

[sumghai]

I've always done it in Blender, is it easier in Unity? Serious question.

Don't the pre-fab connections get messed up if you do it that way? Does that even matter?

In Unity, add an extra "empty" GameObject to the part hierarchy, rename it thrustTransform and align it accordingly. That works perfectly fine and doesn't break any prefabs.

Ok, so I got Unity, and it's stuck at the connecting bit...

http://i.imgur.com/R8uwR2F.png

Good. Cease and desist, and get unity 4.2.2

Oh, alright.

KSP still uses the legacy animation system for things like engine emissives, so you must use Unity 4.2.2.

[Randazzo]

In Unity, add an extra "empty" GameObject to the part hierarchy, rename it thrustTransform and align it accordingly. That works perfectly fine and doesn't break any prefabs.

How does that work with gimbaling? Would I need to parent it or leave it be?

Right now I've got some engines with thrustTransform as parent to the nozzle and some with the Nozzle as parent to the thrustTransform and it never quite looks right.

[sumghai]

How does that work with gimbaling? Would I need to parent it or leave it be?

Right now I've got some engines with thrustTransform as parent to the nozzle and some with the Nozzle as parent to the thrustTransform and it never quite looks right.

I've never made gimballed engines myself, but the following might help you:

http://forum.kerbalspaceprogram.com/threads/28816-Gimbal-Module?p=355601&viewfull=1#post355601

[NecroBones]

In Unity, add an extra "empty" GameObject to the part hierarchy, rename it thrustTransform and align it accordingly. That works perfectly fine and doesn't break any prefabs.

KSP still uses the legacy animation system for things like engine emissives, so you must use Unity 4.2.2.

How does that work with gimbaling? Would I need to parent it or leave it be?

Right now I've got some engines with thrustTransform as parent to the nozzle and some with the Nozzle as parent to the thrustTransform and it never quite looks right.

For gimbaling, I create the thrustTransform in Unity, as Sumghai mentioned, and then move the engine bell's object under it. It breaks prefab, yes, but that's never been a problem for me with engines. So far the only parts I've found that care about that are the landing gear/legs.

Just remember that the location of the thrustTransform's "center" will be the pivot for it to gimbal. So I usually position it at the top of the engine bell for this. If I'm doing a a non-animated gimbal, in which the thrust vector moves but the nozzle doesn't, then I'll position it down at the opening of the engine bell instead.

And yep, you need 4.2.2 if you want to animate heat glow. Later versions took out the ability to animate the emissive color/brightness.

[sumghai]

And yep, you need 4.2.2 if you want to animate heat glow. Later versions took out the ability to animate the emissive color/brightness.

I wouldn't say that it's been "taken out" - rather, from 4.3 onwards, animated emissives require the use of the new mecanim animator component.

Unfortunately, as KSP still uses the legacy animation system, it doesn't recognize mecanim animator-based emissive animations, hence the current workaround is to use the old 4.2.2 version.

[NecroBones]

I wouldn't say that it's been "taken out" - rather, from 4.3 onwards, animated emissives require the use of the new mecanim animator component.

Unfortunately, as KSP still uses the legacy animation system, it doesn't recognize mecanim animator-based emissive animations, hence the current workaround is to use the old 4.2.2 version.

Yep, that's what I meant. Worded badly.