LFS Editor/Guides

From LFS Manual
< LFS Editor
Revision as of 14:28, 13 December 2021 by Flame CZE (talk | contribs) (merge all guides into one page)
Jump to navigationJump to search

This page contains guides for the LFS Editor.

General editor guides

Setting up suspension for bikes

Rear suspension

The "trailing arm" suspension type is recommended for the rear suspension. You create a "trailing arm" object with its object centre at the pivot point for the rear suspension. That must correspond with a "lower pivot" point in the vehicle editor.

Front suspension

In the modeller:

1) Adjust the "steering wheel" (handlebar) object so that the rotation point is aligned with the top bolt - the centre of the top bolt should have x=0 and y=0.

After the "steering wheel" is in the right place, then back in the vehicle editor:

2) Increase the "Trail Reduction" in the "Steering / Driver" section to match the offset between the stanchions and the steering axis. As you do that, the wheel moves forward. So then you reduce the "Forward" value in "Suspension" section by the same amount to compensate. By trial and error you can end up with the steering axis line going straight through the centre of the bolt, then the steering should work correctly.

Vehicle editor guides

This section contains guides for the LFS Vehicle Editor features.

Adjusting masses

Press S for 'special view' in the vehicle editor. You can see the positions of various masses (e.g. engine / fuel tank). You can adjust their positions in the "Object Positions" section. Also you can edit the 'frame' which is only for mass distribution. Frame elements should be placed around the vehicle, as an approximation of where mass would be. You can get the desired mass and weight distribution by adjusting positions of the cuboid masses and the frame elements.

To create a frame element, you first add points then add a frame element between those points. Click 'new point' then use the drag handles to move the point where you want it to be. With a point selected you can click 'dup pt' to duplicate that point. The new point is in the same place as the point you duplicated, so make sure you move it away. To connect two points with a frame element, clicking to select one point, then hold down SHIFT and click the second point. A rfame element should appear and you can change its mass by adjusting the 'TUBE mass per metre' slider bar.

After constructing a frame you may with to increase or decrease the mass of the frame, without adjusting each element individually. In the 'Mass' section, you can see the frame's mass at the top of the list of masses. See plus and minus buttons beside 'Scale Frame Mass'.

  • Left click - big steps
  • Right click - smaller steps
  • CTRL + Right click - even smaller steps

Setting suspension types

To set double wishbone suspension you will need a thrust bearing, and upper and lower pivot. These are points on the car body, created in the vehicle editor in the same way as 'frame' points then set to the appropriate type.

  1. Press S for 'Special Draw'
  2. Click 'new point' (near the top right)
  3. Position this point somewhere inboard of the lower part of the front suspension
  4. Adjust 'Point type' to 'lower pivot'
  5. Deselect that point by clicking on it
  6. Repeat steps 2 to 5 to create an 'upper pivot' somewhere above the lower pivot
  7. Repeat steps 2 to 5 to create a 'thrust bearing' somewhere above the pivot points
  8. Now you can set the type to Double Wishbone (in the Suspension tab at top left)

For single seaters you will probably want to add additional points and tubes so you form a 'wishbone' shape instead of a single rod connecting the suspension to the car.

For examples you can have a look at the existing Formula cars.

After setting up the suspension, press SHIFT+L to see a diagram of the suspension geometry and press SPACE to see how it reacts when the car is dropped. You can also switch on the 'Zero springs test' in 'Suspension' tab (at the top left) to see how the car falls down to the bump stops. This can help you to observe the way the camber changes according to the suspension geometry.

Adjusting aerodynamics

In the Aerodynamics section, the sliders set the downforce values for a theoretical speed of 1 m/s, for a wing at the maximum angle of attack 30 degrees. These values are related to the square of speed, so at 10 m/s the downforce and drag values will be far higher than the theoretical values. You can see a representation of the downforce and drag at various speeds in the "Downforce" tab at the bottom right of the screen.

  1. Hide the bottom right editor buttons by clicking the '-' button in bottom right corner
  2. Select the 'Downforce' tab of the default setup
  3. Adjust the 'Test speed' to see how much force you will get with the default wing settings

NOTE: The downforce and drag forces are applied at the locations of the aerodynamic subobjects of the model. In the modeller, in 'subob' mode, these subobjects are shown in blue and have a letter code indicating their subobject type:

R - rear wing
F - front wing
U - undertray
C - aero centre

Simple optimisations

Concealed Wheels (in Wheel Object section) - Please use this option if the inside of your wheels is fully concealed (e.g. most road cars). The most obvious difference is that the tyre manufacturer logo will not be drawn on the inside of the wheel. Also the spokes may not be drawn when the wheel is seen from the hidden side. A case where you would not use this option: single seater racing car.

Concealed Driver (in Wheel Object section) - Please use this option if the driver's body is not usually visible. This is the case for most cars (e.g. road cars and single seaters) and can help the frame rate when there are a few cars around. The helmet will be drawn in any case but the driver's body will not be drawn if the viewer is firther away. Some cases where you would not use this option: karts or motorbikes.

Driver animations

In the animation editor you can edit the sit and steer animations. Press A in the vehicle editor to enter the animation editor. Buttons to save and load animations are at the top left. Driver animations are named str_xxx and passenger animations (which have a single frame) are named sit_xxx. The 'xxx' part of the name is up to 7 characters and can be set in the 'Driver' section in the vehicle editor.

To edit a steering animation: (LMB = left mouse button)

  1. Enter animation editor by pressing A in the vehicle editor
  2. Note the buttons 'show skeleton' and 'show object' at bottom right
  3. Select an individual frame on the timeline at bottom left
  4. Select any bone you want to move or rotate (switch 'show skeleton' on and 'show object' off to make this clearer)
  5. Hold Q/W/E for x/y/z rotation - rotate by dragging left or right with LMB
  6. Hold A/S/D for x/y/z movement - drag with LMB in relevant direction
  7. Check for smooth movement by moving the timeline slider
  8. Click "SAVE as STR" to save the file (in your data\move folder)

NOTE: The steering animation should contain very little head movement and rotation. The game automatically applies head rotation and lean in real time for steering and lateral force.

Editing dashboard

In the dashboard editor you can edit the positions of various parts of the dashboard, or switch some gauges or lights on or off. In the vehicle editor open the "Class / Textures" tab. Beside the word CLOCKS you can click to select the dashboard type. This strange looking name, e.g. "s_clock_formula" is actually a specially named live texture that you can enter in 'page' mode in the modeller, as a texture page either for the main object or a subobject. To edit the selected dashboard, click the EDIT button. It is a good idea to switch off any lights or gauges you don't need.

Collaboration - More than one person working on a mod

There is a feature to help with sharing a complete mod with its development files. Unlike exporting for upload, this function copies png files rather than creating dds textures. It doesn't automatically create a zip. It simply gathers all the files and saves them in a structured share folder ready for copying.

After creating the initial vehicle and working on it a bit, you can click "export to share vehicle for development" at the top right.

That exports veh, engine sound, animations, png in a directory structure in a 'share' folder. So you can zip up those folders inside 'share', send it to your collaborator who will unzip it to 'data' on their computer. Now the exact same mod exists on both computers.

From that point on, if only the collaborator works on it they could do the same to return the updated mod back to you. But if you both continue to work on the project at the same time you will probably manually share updated files.

Two people should usually not work on the actual vehicle editor settings at the same time, as you would need to manually merge the changes. It may be that one person works on the vehicle settings, while another works on the 3D model. The 3D model can be saved out from the modeller and sent to be loaded in on the remote computer. A complete wheel style file can also be saved or loaded - save WHL / load WHL in the wheel object section. Engine can also be saved separately.

There is also a function "export for DV" in the Class/Textures section. This copies all png textures to data\png_export. For example the person working on the 3d model might save the 3D model into data\3dob and do a png export then send those files to the person working on the veh. The veh person would then save the png files into data\png load the model (in the modeller, accessed from the vehicle editor).

Modeller guides

This section contains guides for the LFS Modeller features.

Background images

You can load background images to help with modelling.

  • Save a square png image (probably 1024x1024 or 2048x2048) in your data\bkg folder
  • Go into a 2D view (R/F/V etc)
  • At the bottom right click "load bkg" to load your image
  • Click "adjust" then use the mouse to adjust the position and size
  • After clicking "adjust" you can also click "bkg scale" to type in the scale
  • Repeat the steps above for any of the other main 2D views
  • Then click "save scm" which saves the whole scheme of adjusted backgrounds so you can easily load it next time
  • The "use opposite" option: for example on the left side it will use the right side image and position, automatically flipped

Customisable colours

You can set colours to be adjustable, when a user enters the garage screen and clicks "New colours".

This is done by giving some of the mappings a special name. Each mapping has a colour, but sometimes you want several mappings to have the same colour. For example the top and side mappings of a car. You can define a "Main" colour and "Copied" colours. So for example you could set top mapping to be a Main colour, then assign the side, front and rear mappings to be Copied colours of the top. Main colours are identified by the letter M followed by a number, while copied colours are identified by the letter C followed by the same number.

Taking the example above, you could name your mappings (colours) like this:

    M1_top
    C1_side
    C1_front
    C1_rear

As soon as you set the names this way, you will notice the C1 colours aren't adjustable in the modeller. You can adjust the M1 colour and all the C1 colours will take the same value. Also this colour is now adjustable by the user, in the settings block. You can see that in the vehicle editor in the Colours section.

You can allow more than one customisable colour group, as seen on some of the LFS cars. This is done by creating M2 / C2 colours, up to a maximum of 4 customisable colours.

Note 1: You can use copied colours without them being adjustable by users. Use higher values than 4. E.g. M5_original and C5_copy.

Note 2: Customisable colours are also available for subobjects. To use this feature, select the subobject and switch on "use custom colours"

Advanced: You can also create a darker copy of the main colour, by using the prefix 'D' for dark or 'E' for extra dark. This can be useful to fake reduced ambient lighting if you are adding surfaces in a place where there should be less light. For example:

    M1_main - the user can set this colour
    C1_copy - direct copy of M1_main
    D1_dark - darker copy of M1_main
    E1_extra - extra dark copy of M1_main

Light colours: headlights, indicators, etc.

All light mappings have a name with prefix "l_"

The cutouts for all light mappings must share a single texture page.

The special names for light mappings are:

    l_brk - brake (main mapping of brake light)
    l_sbrk - side brake (e.g. side of a curved brake light)
    l_tbrk - top brake (e.g. top of a curved brake light)
    l_cbrk - centre brake (e.g. brake light in rear window)
    l_head - headlight (main headlights)
    l_side - side light (smaller lights near headlights)
    l_tail - tail light (red rear lights)
    l_stail - side tail light (e.g. side of a curved tail light)
    l_ttail - top tail light (e.g. top of a curved tail light)
    l_rind - rear indicator
    l_find - front indicator
    l_rsind - rear side indicator
    l_fsind - front side indicator
    l_rfog - rear fog light
    l_ffog - front fog light
    l_rev - reversing light

Level of detail (LOD) and Shadow / Physics / Collision meshes

When you first start work on a mod, you can test it in LFS with only a single level of detail. That is the main graphical LOD, known as LOD1. But your mod cannot be uploaded to the website like that. It needs at least a physics or collision mesh, and finished mods should usually have a shadow mesh too.

There are two possible LOD choices for a mod you upload to the website.

Work in progress / test mod - 2 levels of detail

LOD1: The main graphical LOD
LOD2: The low resolution physics / collision mesh

In this case, the collision mesh doubles as the shadow casting mesh. For most models this approximation is too crude, because the collision mesh is very limited in the number of points and triangles. But it's fine for early testing.

Completed mods usually have 3 levels of detail

LOD1: The main graphical LOD
LOD2: The shadow and distance view mesh
LOD3: The low resolution physics / collision mesh

In this case, LOD2 is drawn when the mod is in the middle distance. This saves the graphics card doing a lot of work drawing detail that you can't see and helps with frame rate. This LOD should be a good representation of the shape of your mod, so it looks good in the distance, and casts a good looking shadow. LOD3 is only used as a visual representation when the mod is very far away. Its main purpose is for collisions with other vehicles or when your mod hits a wall or rolls over.

How to add an automatically created physics / collision mesh

  • In the modeller, click the + (plus) button to the right of lod1 (near the top left) to add a new LOD
  • Now select lod2 or lod3 (the newly created, empty LOD)
  • Click "auto-create collision mesh"

The automatically created collision mesh is created based on the size of the existing LOD1 (high detail) mesh. This should provide basic collision physics but you will probably want to improve the shape to make it a better match for your vehicle.

Draw order of materials

You can see a material list in the vehicle editor "Class/Textures" tab. That should represent the draw order of the materials.

To actually change the draw order of the materials, you adjust the draw order of the cutouts in the modeller. The draw order is assigned by the order the materials are first encountered in the cutout list. The material's index is the number on the right of the 'material' column in the list of cutouts.

The idea is to make sure the material for the steel frame appears in the cutout list before the material for the cloth cover. For example if you selected a material with material index '2' and move it to the top of the list, then on reaching the top, it should acquire material index '1'. What was material 1 will become material 2.

Draw order of individual triangles

Within materials, triangles are drawn in the order they appear in the internal list of triangles. LFS doesn't give you direct control over this list, but you can improve the draw order by clicking "magic triangle sort". This function tries to adjust the draw order so that further away triangles are likely to be drawn first. This may be better than randomly ordered triangles, and may help with "Z fight" problems if the nearby surfaces share a material so you can't manually correct the draw order by ordering the materials.

Creating a SKIN texture

A skin is a special texture designed to cover the paintwork of your vehicle so that other people can create their own custom paint jobs. The idea is to uniquely cover the whole paint surface of the vehicle without any part of the texture being used more than once. As a mod creator you may take on the task of creating a default skin that people can modify to use when driving your mod. Here are a few tips for designing skins.

A skin must be created as 1024 or 2048 square image. To load it into LFS it must be saved as a JPG in your data\skins folder, with a name like ABC123_NAME.jpg where ABC123 is the Skin ID of your mod and NAME is a name for the texture (usually DEFAULT for a plain texture).

The artists who create custom skins prefer everything lined up as well as possible, so try to use the options "link with SIDE" / "link with FRONT" / "link with BACK" / "link with TOP" for the main mappings, so your mappings have the correct width.

You can type in the height of the mapping, to make sure front, back, side mappings have the same height. You can also type in the right, front, up values.

Try to keep the pixels of your mappings fairly square (cutout has a similar aspect ratio to the mapping). The squarer they are, the easier for your skin artists.

TIP: Not *everything* needs to be skinned from a proper direction. E.g. skin artists may be quite happy with a single mapping for a wing mirror, probably from the front, that goes right through the object (so the side and top surfaces are not individually mapped). Smaller mappings don't 'link' with any other mapping.

Skins on models with complex shapes may have the added complication of overlapped areas. So you should plan this in advance, where you want the MAIN top, front, side, back mappings and allow enough space for the overlapped areas to be mapped separately. You may wish to follow the general idea of one of our default skins, and change it to suit your needs.

You may find the "copy screen shot" function useful. It takes the correct size screenshot of the mesh for the selected mapping, and copies that to the clipboard so you can paste it into your work-in-progress skin in your 2D graphics software. Before using this function, use a white (or light grey) car colour, and move the lighting UP by using CTRL + left

Importing from other 3D modelling software

You can import the points and triangles from another 3D program by exporting an OBJ file and loading it into LFS from the data\obj folder. Texture mappings and materials are not imported.

How to export from Blender:

Scale

LFS uses metres for units. If you use another unit, please export using an appropriate scale.

Position

Your model should be approximately centred over the origin and ideally the body should sit on the ground (without the correct ride height)

Backface culling

Live for Speed uses single sided triangles. While modelling in blender and before exporting, make sure you look at your model with back face culling enabled so you can be sure the surfaces are facing the right way.

Export Settings - Export OBJ file

Transform:
- Y forward / Z up (so the model is oriented correctly in LFS)

Geometry:
- Write normals (so LFS can work out smoothing groups)
- Triangulate faces (as LFS geometry is based on triangles)

Extrude and Lathe functions

To use the extrude or lathe functions, first you select a series of points in order to create a cross section that you will either extrude linearly (extrude) or rotate around a point (lathe). You can see the cross section by enabling the 'trace' option in point mode, then selecting points in the correct order. It can sometimes be confusing which order to select the points, and then choose 'inside' or 'outside' to get the desired effect.

Extrusion

  • Put your viewpoint on the side so that you will pull the extrusion towards you
  • Select the trace points in anti-clockwise direction as seen from that point
  • Create extrusion by clicking 'extrude' (and select outside, inside, etc.)
  • Pull the points towards you

Then you should find that your inside / outside request is respected.

Lathe

  • Put your view on the side where the lathe operation will initially head towards (at the start of the curve)
  • Select the trace points in anti-clockwise direction as seen from that point
  • Rotation will take place around the last point you select (which may or may not be included as part of the cross-section)
  • Go to 2D view and create lathe object by clicking 'lathe' (and select outside, inside, etc.)

Moving parts of a model to a different model

This is done by saving a subobject from one mesh and loading that subobject into another mesh. In 'subob' mode, with a subobject selected, you can see light green 'load' and 'save' buttons beside the word 'subobject' at the bottom left. These will load and save subobjects with the extension '.sre' in the folder data\3dob.

But what if the parts you want to move are not part of a subobject? In this case you can use the 'break off' and 'merge' functions.

  • Create a new empty subobject
  • Select the triangles in the main object that you want to move to another object
  • Click the "break off" button
  • The triangles (and mappings) are moved into the new subobject
  • Save the subobject
  • Load the mesh where you want to add the subobject
  • Add a new, empty subobject to that mesh
  • Load the saved subobject into your new empty subobject and move it to the right position
  • Optionally, click "merge into main" to merge the new subobject into the main object