#lightmaps

Light maps her face with tenderness and tension, and in that fragile stillness she looks like someone learning how to remain.

Unreal Engine Setup

I first of all decided that the main priority would be to setup the Unreal Engine project for the VR preview. As this was an unchartered territory for me, I decided to make sure the Engine was up and running well.

There are two ways you can opt for setting up Unreal Engine for a VR preview. You can either build the VR template blueprints from scratch or you can choose the VR template provided by the Unreal Engine inside the 'Games' tab. I opted for the latter as I was already on a tight schedule and I decided to work on the project solo as others had already formed pairs and groups to work together. This was a challenge to myself to engineer everything and make sure the game is running flawlessly.

Figure 1 (Unreal Engine templates)

I also set up the lights for the environment immediately so that I could get a sense of what I am working with. I went with a default setup of a directional light and a sky light for the atmosphere. Interestingly, since we are working towards a VR project, Lumen wouldn't help the case and we need to bake the lights for the entire scene manually. Just to prevent the scene from even using Lumen, I turned it off in the project settings and also enabled the virtual texture support to incorporate static meshes blending with the landscape.

Figure 2 (Lumen Turned Off)

Figure 3 (Virtual Texture Support Enabled)

The procedure of baking the lights is a bit confusing at times but one I am fairly familiar with as I have done simple architecture visualization projects where baking proved to be quite useful. Before baking the lights of the level, you also need to make sure that the lightmap texture density of the static meshes is enough. You can preview the visualization of the density of the lightmaps of the meshes inside the 'Optimization Viewmodes' under the 'Lit' tab.

Figure 4 (Optimization Viewmodes)

If a mesh doesn't have sufficient density of lightmaps, the scene after it's been baked is poorly lit and very dark. Inside the visualization, you can see the color of the lightmap density of the meshes to ensure its properly lit after baking. You can find the information in official documentation released by Epic Games, but basically, blue means the lack of sufficient density, green means sufficient density and red means excess density.

Figure 5 (Lightmap Density Color, (ICVR, 2024))

Whenever you increase the lightmap of the static mesh, you should keep in mind to make sure that the value you insert should be equate to the answer of base 2 to the power 'n' where 'n' is any number you choose, i.e. 2, 64, 128 and so on. The Unreal documentation does state it does not need to be that value but I believe its an editing mistake as the lightmaps won't be distributed equally to the entirety of the mesh, resulting in baking artifacts.

After creating the Unreal project and setting it up for light baking, I move to the next phase which would be spent on creating a sandy tile texture for the landscape.

REFERENCES

Jim Scott at blackpawn.com:

Pop Quiz: You have 765,618 lightmaps for a scene and very few of them have power of 2 dimensions, what do you do? If your answer was to rescale them and call CreateTexture 765,618 times please slap yourself. If your answer had anything to do with glTexImage2D, you might want to leave now. What you really want to do is smush them all into a couple larger textures, and this text will show you one way of doing it.

Specular Highlights with Directional Lightmaps

Hi, i’ve been adding directional lightmaps to an old DX9 engine, which is working fine, but i wanted to have a go at adding specular highlights for static lighting. I’ve heard that other engines such as Unity and UE3 have this but my google-fu is failing me as I can’t find any solid implementation details. So, i’ve had a blind stab at it mysel… GameDev.net Forums RSS◄ Click to View Complete thread…