[Tutorial] How to build lower lods.

[Tutorial] How to build lower lods.
Date: December 31, 2008 12:37AM
Posted by: Excalibur

Registered: 17 years ago

Tutorial: How to make lower lods?

Hello everyone! I have written this tutorial on the method which consist to get lower lods from the original carshape. You may spend time on your first lod but once you have understood how it works, it will be faster. So, be patient and follow the procedure.I apologize for my english which is not very good but I hope you will understand. Correct me if there are big mistakes.Now, let's go:

Items required:

1: original car shape.
( car_carname_car1_lod_0.gp4 or car_carname_car2_lod_0.gp4)
2: Textures of the car ( tga files)

Tools required:

1: GP4Renamer by Öggo Mediafire
1: Zmodeler LINK
2: 3DSMax or 3D Photo Browser for 3D users + polygon cruncher Link
3: Polygon cruncher 7.8 trial version (limited to 7 days, full application) with 3DSMAx method only Link
4: GP4Builder Link
5: Texresizer Link or Slimtex (ZAZTools) GP4DB

Tutorial into PDF version: How to make lower_lods by Excalibur
Thanks to Foreverk for the PDF conversion.

Note: Polygone Cruncher V 7.8 is not a freeware. This is why it is limited to 7 days but with full options. Then, you can buy it on Mootools's website. The MultiRes function is free under 3DsMax.

Method:

I used Zmodeler v1.07b, 3DSMax2009, polygon cruncher trial version , GP4Builder V1.181
and also Texresizer 2.5 to extract the tga files from the car's textures.

Credits:

Thanks to Jorge Caranti and Raulongo who helped me out getting started and explained some basic concepts.
Thanks to Gezere for his precisions concerning the 3D objects of the car and the lod_4.
A big thank to Öggo for his great tool.

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Part 1 : Pre-work

Be sure you have into a same folder: the GP4 files (cars) and all the textures into tga format.
Making this, you will save time when you will have to re-assign textures on the lower lods.
To convert .tex files into .tga files, use Slimtex (ZazTools) or Texresizer by LO2k (RealGPX.com)

Note: Don't forget to flip your textures when you convert them from tex to tga (and also from tga to tex)

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Part 1 : Create a 3DS file with Zmodeler.

Rename 3D car objects with GP4Renamer:

It allows to rename car objects to be compatible with 3DSmax:

1- Select your main file: car_carname_carX_lod_0.gp4
2- click on the "Auto Rename" button.
3- Save and exit

Open Zmodeler:

1- Import your shape into Zmodeler.

Note: It may happen that you got this message when you try to import a car: «File is locked or has an invalid header»... So, You have to open it into GP4Builder and then to save it as a .gp4 file. Finally, import it into Zmodeler.

2-From lod_0, we can delete 3D objects of the car for the lower lods. Delete these parts:

insert
left_mirror
right_mirror
visor

3- Export your file into .3DS format.

You will get this message in a window: "The following operations have been performed to make file compatible with 3D Studio" . Press ok!

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Part 2: create lower lods with 3dsMax2009 or 3D Photo Browser and Polygon Cruncher
.

There are 3 methods to do this:
- With Polygon Cruncher under 3D Photo Browser
- with polygon cruncher under 3dsmax.
- with the multires option under 3dsmax only.

1- Method with Polygon cruncher and 3D Photo Browser:

This is my favourite method. Why?
- It is simplier and faster
- Polygon cruncher allows you to reduce the weight of the shape while maintaining the highest quality possible.

Open 3D Photo Browser and select the original .3ds file you wan to reduce to get the first lower lod (lod_1)

On the new window, click on the arrow and select "Polygon cruncher"

Now, tick the boxes as follows. Then, click on "Calculate the value of the scene (3)

Now, we have to set the percentage of reduction for the lod_1:

Here is the percentage of reduction to apply for each lod:
- lod_1 = 30%
- lod_2 = 50%
- lod_3 = 70%
- lod_4 = 80%

Once the percentage is set for the first lod, click on the "Aplly" button and save the file with the options by default:

Close the window and start the same procedure again from the original 3ds file for the lods 2, 3 and 4.
Finally, you will get 4 lower lods.

Note: Do the same procedure for the car 2.

2- Method with Polygon cruncher:

First, import your 3ds file into 3dsmax.
Then, click on the icon utilities and click on «more» to select the Polycruncher plugin:

When you see the plugin in the right window, click on « optimiser la sélection» (in french) or «optimize the selection» (first button)

Tick the apropriate boxes (1 and 2) before to click on « Calculate the optimization of the scene» (3)
as below:

Now it is done, we are going to set the percentage for each lod.

The values:

Here are the values that I precognize but you can modify the car with the values you want:

Lod0 = 100%
Lod1 = 80%
Lod2 = 65%
Lod3 = 50%
Lod4 = 30%

It depends of the quality you want to keep when you see a car far from the others into the game. The more you reduce the car, the more you will loose details of the shape. But don't worry, when a car is around you, it will always use Lod0 (best quality). Reducing lods allows you to not overload your PO during a race and it is not a problem because when a car is far in front of you or far behind, you can't see all the details anyway.

So, here is the procedure for Lod1: We want to reduce the shape at 80%, so you have to move the arrow on the left until 20% (1) .you can also adjust the % by modifying the faces numbers or points numbers. Then, click on the apply button (2):

Once done, export your file into .3ds format with the name «car1» or «carlod1». The box «preserve Max's textures coordinates» must be ticked before clicking ok.

Now, you've got the shape for the Lod1...

Then, click on edit and undo polygon cruncher and restart the same procedure for the lod 2, 3 and 4.

You will have to set these values into polygone cruncher:

Lod1: 20% to get a car at 80% from the original
Lod2: 35% to get a car at 65% from the original
Lod3: 50% to gat a car at 50% from the original
Lod4: 70% to get a car at 30% from the original

Finaly, you have 4 new 3ds files for lod 1, 2, 3 and 4.

2- Method with the multires option under 3dsmax:

1- click on the «mofifiers» tab, «Mesh Editing», «Multires»
2- click on generate
3- change the vert. Percentage like this:

For lod 1: 90%
For lod 2: 80%
For lod 3: 70%
For lod 4: 65%

Note: Q: Why not the same values than Polygon Cruncher?
A: Because with Multires, if you set your % under 65, you may lose car parts.

4- save each shape by exporting it into 3ds format, undo and start again the procedure for the other lods.
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Part 3: Rename car parts and assign textures with Zmodeler.

Important note if you made your lower lods with 3D Photo Browser:
When you import your cars into ZModeler, you will see this message: "Invalid #AmountOf# chunk!" Don't worry, this is not an error, click on ok and continue until the car appears (you will see this message as many times as there are textures assigned for this file).

1- Assign textures with Zmodeler:

First, we need to get all the tga files from the car. If you just have the textures (.tex), use Slimtex or Texresizer to convert them into .tga files.

Example: I want to get the tga files of the mp4-23.tex:

1- Open mp4-23.tex with Texresizer
2- «Save all4 tga files» in a folder
3- You get 4 files:- mp4-2310.tga
-mp42311.tga
-mp4-2312.tga
-mp4-2313.tga
4- Just keep the mp4-2310.tga and delete the others.
5- rename mp4-2310.tga into mp4-23.tga
6- Do the same thing for all textures of the car.

To know which are the textures of the car, in Zmodeler, import the original shape and go to material editor (or press E) .Look at the list:

Now, we are going to reassign each texture of the car to the 4 shapes (or lods)

Keep your original shape opened in Zmodeler. So, you have 2 windows: one for shape 0 (original) and one for shape 1 (or lod 1).

The textures of our original car are well ordered: In our example from mp4-22_carbon.tga to carlightmapch3.tga (from 1 to 10).Now into the window of your shape 1, open material editor and look at the list : you see «default material» and «material#1» to « material#8» but not in order:

The aim is to reassign every texture in the right order: Select the material and rename it :
The first texture of our original shape to material#1 of the shape 1
The second texture of the original shape to material#2 of the shape 1 etc..

In the example: you have to copy the name « mp4-22_carbon.tga» and paste it to material#1
Same thing with « cockpit_dammage.tga» and paste it to material#2 etc...

Note: You don't have to re-assign the CARLIGHTMAPCH textures because GP4Builder will do it automatically into the last step ( Part4)

Do it for each texture of the car. Beware of the order. It is very important. At the end, you will get something like this:

Shape1Original shape

Now, let's see if your textures are correctly assigned:

1-Select the first texture name in the list , tick Primary texture and click on «Load Map» button .
2- Click on the «Add» button and select the tga file corresponding to the file's name.
3- In «Type» tab, select «unused» for each texture.

Note: You don't need to load the carlightmapch textures.

Do it for each texture and then, click on «Ok». See the result.

4- If ok, export the lods 1,2 and 3 in .gp4 format with the good name for the lod: car_carname_carX_lod_X.gp4

2- Last modification for the lod_4:

This last modification is not compulsory 100 %, I don't know if it has an impact on the PO, but it allows you to keep your file into GP4 standard.

- Select - All
- Create - Objects - Uniteselect
- click on the shape (whatever the view mode)
- Give the name "cockpit_low" ....So, you just got 1 object at the end.
- Export the new lod_4 into.gp4 format and name it as:
car_carname_carX_lod_4

3- Rename car objects as the originals with GP4Renamer

1- Load your car_carname_carX_lodX.gp4 file
2- click on the "Auto Rename2" button
3- click on "Save" and exit.

Do this procedure for lods 1,2 and 3 ( we have modified and named lod4 object before).

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Part 4: Sort car objects with GP4Builder.

The last and easiest thing to do:

First of all, you have to rename the z_cockpit_right_mirror and the z_cockpit_left_mirror for lod_0 of the cars manually because GP4Renamer doesn't do it:

1-Open your file with GP4Buider
2- Double click on "Scenes 1" and "Scenes1 28"
3- Look for right and left_mirror and rename them manually into the Object's attributes window (z_cockpit_right_mirror and z_cockpit_left_mirror)
4- click on the «Action» tab and select «sort car objects»
5- Save your file with «save as»

Do the same procedure (4 and 5) for lods 1,2 and 3 ( no need with lod_4 because it has just 1 object if you have followed the modification above)

It is done! You've got 4 lower lods + the original lod 0 for the car1:
car_carname_car1_lod_0.gp4
car_carname_car1_lod_1.gp4
car_carname_car1_lod_2.gp4
car_carname_car1_lod_3.gp4
car_carname_car1_lod_4.gp4

Now, repeat the same procedure for car2 because textures ( driver'sname, number of the car, Tcam color ect..) must be assigned for the second car correctly.

or you can just copy and paste all the lods from car1 and rename it as below if you got the same textures for the 2 cars:

car_carname_car2_lod_0.gp4
car_carname_car2_lod_1.gp4
car_carname_car2_lod_2.gp4
car_carname_car2_lod_3.gp4
car_carname_car2_lod_4.gp4

That's done!

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Edited 29 time(s). Last edit at 07/24/2020 10:08PM by Excalibur.