DXTre3D editor

Terminology:

In this small chapter I would like to say something about the expressions you will soon come across. Therefore, read it thoroughly, because it is not a subject as a subject.
Pixel - It is the smallest unit of measurement in the editor.
Sector - Another unit of measurement used in conjunction with rooms.
Block - This is the basic building block in the editor. Its base size is 64x64x64 pixels. It can also be divided into smaller parts. Actually, the whole level consists of such blocks.
Room - Here it is necessary to distinguish whether it is a room in the editor or the level itself. The room in the editor is actually the next building element of the editor right after the Block. It can be 1x1x1 sector up to 18x18x5 sectors (1 sector corresponds to 64x64 pixels). It might seem a bit confusing to you now, but you will get used to it very soon. In contrast, the room in the game is nothing more than a classic room (room, hall, garage), however, it can consist of several editor's rooms.
Item - Subject. It is about some part in the level that is not created by a geometric shape. It can be some columns, furniture, means of transport, but also weapons, pharmacies, Lara herself and many others. These subjects are further divided into:
Static Item - Static item. From this name it can already be deduced that these are all subjects, which Lara cannot manipulate in any way and only serve as decoration in the level. But even these items are further divided into Plant, Furniture, Rock, Architecture, Debris and Shatter. Some can even be used to activate Trigger - Item_At_Sector. They are Shatter, which can be shot and thus activate the Trigger. Some can only be broken by enemies and trigger the Trigger again.
Objects - For a change, these are objects that Lara can somehow manipulate. And even these items have their own subgroup Pickups. Pickups are items that which Lara can not only use, but also pick up and they will then appear in the inventory.
Triggers - Or triggers in Czech. These are the commands by which the game is governed and thereby executed what the author of the level wanted in interaction with the player. These commands will only wake up the level and all Objects in it come to life and thus complex puzzles or rooms guarded by enemies can be created.
Door - This is not a door, as the translation of this word would suggest, but o Portal (link) between two rooms. The entire level is composed of interconnected rooms. And these rooms are connected by portals.
Engin - The literal translation would be engine. But in this case the title Heart would be more appropriate, or the Brain. Are you asking why? It's simple. Engine means the algorithm that controls the running of the game itself. We can actually say a program that allows us to see anything at all on the computer screen.
Compilation - This is the process by which the editor generates a playable level. It is important not to confuse this with saving the Project!

Level optimization:

What can you imagine under this title? The point is that this editor can create levels for all parts of TR. And since the engine of these games has evolved over time, it is necessary to realize when creating your own level, to which TR the given level is intended. Hopefully it is clear to everyone that what they can afford for the TR-4, it certainly won't go in TR-1. Here I would like to draw attention to these differences and at the same time state such main principles for creation.
We will probably start with the simplest one, namely the individual level restrictions. I will always list here what the given TR does not support.

TR-1:
-Triangles
-Climbing over the corner of the pillar
-Transparent textures
-Alternative room groups
-Flare (not that it will be too dark there)
-Moving sky (doesn't support any, only closed rooms)
-Flying cameras
-FX-Effects
-Colored lights
-Colored lights for Lara's Light (white only)
-Smooth transition between levels
-Handling on the ceiling (only on the wall)
-OCB codes
-Zoom in camera settings
-Some Triggers (need to check)
-No weather effects

TR-2:
-Triangles
-Climbing over the corner of the pillar
-Transparent textures
-Alternative room groups
-The Moving Sky
-Flying cameras
-Colored lights
-Colored lights for Lara's Light (white only)
-Smooth transition between levels
-Handling on the ceiling (only on the wall)
-OCB codes
-Zoom in camera settings
-No weather effects

TR-3:
-The Moving Sky
-Climbing over the corner of the pillar
-Alternative room groups
-Flying cameras
-Colored lights for Lara's Light (white only)
-Smooth transition between levels
-OCB codes

TR-4:
-No weather effects

TR-5:
-Alternative rooms
-Alternative room groups

This was a list of most things that should not be used in conjunction with that level. Of course, it doesn't have to be all of it, and in time you will definitely come up with something.
Here are a few more specialties that differentiate individual levels.

TR-1:
-If you texture the water surface, only the ceiling of the room with the water is textured, and that with a semi-transparent texture.
-If you want items (enemies) not to be seen immediately, you must give them Invisible.
 
TR-2:
-If you texture the water surface, only the ceiling of the room with the water is textured, and that with a semi-transparent texture.
 
TR-3:
-If you texture the water surface, only the floor of the room is textured, which is above the water room and the Double Side attribute is added to the texture. The texture can be semi-transparent or transparent.
-Supports water effects
-Supports Item :Kill all triggers
 
TR-4:
-If you texture the water surface, only the floor of the room is textured, which is above the water room and the Double Side attribute is added to the texture. The texture can be semi-transparent or transparent.
-Supports water effects
-Supports :Trigger Triggerer
function -Supports fog effect
 
TR-5:
-If you texture the water surface, only the ceiling of the room with the water is textured with a semi-transparent or transparent texture.
-Supports Item :Lara position changer
-Supports fog effect

This should cover the editor support for the various parts of TR. We could also say a few general rules for creating levels.
The first thing I will mention is the observance of the maximum number of items per room and for the entire level. In part, this issue is already discussed in the instructions for the FexMerger program, where it is written how many static and normal objects can be placed in one level at once. It is not recommended to exceed these values, otherwise there is a risk of considerable difficulties. At the same time, it's a good idea to use a reasonably sized texture panel. Except for the textures for the rooms there are also textures for all objects in the level. This in combination with a large panel of textures and of many items in the Base Level leads to the instability of the whole game.
Another very well known problem occurs if you use larger rooms like 18x18 blocks in your level. By that I don't mean so much the room in the Editor (you won't make a bigger room there anyway), but the room in the game, which consist of several interconnected rooms. In such rooms, artificial reduction occurs supervision and thus, for example, incomplete rendering of geometry or imaging occurs horizon in the middle of the room. It looks pretty ugly in game. Therefore, if you can, avoid large rooms.
Another very well-known problem is with many Objects running at once. For example, it can be various lit fires, running enemies and such. It's always good if Lara isn't in the room, where these items are used and he can't even see them from anywhere to deactivate them. This can partially eliminate the effect of flickering fires or smoke passing through the walls. At the same time, it is of course not good if you cram 50 enemies into one room with Lara and activate them at once.

And at the end of this chapter, the limits of individual levels:
 
TR-1:
-Size of items in the level: 400-500Kb
-Number of Static Mesh :50
 
TR-2:
-Size of items in the level: 500-600Kb
-Number of Static Mesh :50
 
TR-3:
-Size of items in the level: 600-700Kb
-Number of Static Mesh :50
 
TR-4:
-Size of items in the level: 600-800Kb
-Number of Static Mesh :60
 
TR-5:
-Size of items in the level: 600-800Kb
-Number of Static Mesh :60

General limits and recommendations:
Number of rooms per level: up to 150-200 depending on the size of the individual rooms.
Number of subjects per level:255 (I do not recommend more than 220)
Number of Static Mesh per room :30
Number of lighting points per room:12-40 (according to the editor version)
Number of cameras per level :99
Number of Flying Cameras per level :60
Number of Items for one Trigger:15
Number of sound effects per level (Sound Sources):32

And here, unfortunately, the instructions here on the website end. If, however, you want to continue your studies, visit the page with PDF instructions, where you will find the continuation of this guide:
PDF Instructions