Optimize the scene

[juanmajr93]

Hi all, do you know anyway to render only the models that are near of camera (I would define a radius and I can only see the models inside this area) is it possible?

 

Thanks!

[Temechon]

Hi, 

There is nothing implemented in the framework. But it's easy to do it!

For each frame, do : 

• For all meshes, do :
  • Compute distance between camera and the current mesh
  • if the distance is > MAX_DISTANCE, do : mesh.setEnabled(false);
  • Else, do : mesh.setEnabled(true);

"For each frame' = scene.registerBeforeRender()

"For all emshes" = scene.meshes

"Compute Distance" = BABYLON.Vector3.DistanceSquared(camera.position, mesh.position)

Good luck

[Raitch]

Sound like you want to use this: https://doc.babylonjs.com/tutorials/how_to_use_lod

Examples if you want `mesh` to not be rendered after 50 units: `mesh.addLODLevel(50, null);`

As you see in this example you can also have more simple versions of a mesh at a longer distance: http://www.babylonjs-playground.com/#QE7KM

[juanmajr93]

@Temechon @Raitch it is well but it is not exactally that I want. I only want to show the part of scene which are near of camera but not disable all mesh unless render only the part that is nearer to me..

[Raitch]

It sounds like we're talking about the same thing. My solution does't disable meshes. It only checks if it should be rendered depending on camera distance. 

Apart from that Babylon JS often doesn't render meshes behind the camera to save process power, so that part is already optimized. 

Perhaps you mean like a Silent Hill fog effect or how would you wish the distance to be visually shortened?

[juanmajr93]

yes just it! @Raitch I have to short the visual distance and try by this way to reduce the effort to render all models of my scene (frustum planes)

[Raitch]

I would suggest that you try a combination of scene fog: https://doc.babylonjs.com/tutorials/environment and LOD as I linked above. The fog doesn't exclude meshes from being rendered, but you can set for example:

    ^{scene.fogMode = BABYLON.Scene.FOGMODE_LINEAR;}

    ^{scene.fogColor = new BABYLON.Color3(0.9, 0.9, 0.85);
    scene.fogStart = 20.0;
    scene.fogEnd = 25.0;}

And on all relevant meshes run: `mesh.addLODLevel(30, null);` 

And on active camera set `camera.maxZ = 30;`

Hiding the meshes wouldn't be noticed since the fog ends before their condition is met. 

[inteja]

Camera far clipping plane i.e. maxZ?

[Raitch]

I doubt a plane mesh would take much to render the entire of it?

If it's on a flat surface I guess you would have a plane as big as the fog ends, move it under your character and position the plane's texture with .uOffset and .vOffset, if I follow you correct. Maybe even have different planes next to each other with LOD if you have giant textures.

I could very well be misunderstanding your question now.

Okay, you can use fog and `camera.maxZ = 30;` instead of LOD on all meshes. I did not know that.