Effective system load?

[Dinorius_Redundicus]

I'm seeing some recent assets on the DLS with descriptions like this;

"The effective system load of this asset is 7566 polygons (1866 from geometry, 5700 from textures)."

I'm supposing that 1866 means the number of triangles in the mesh, but how is "5700 (polys?) from textures" arrived at? How many actual texture files does that represent, or more importantly, how many Materials? Is it a meaningful number? It sounds like a seriously excessive number of textures, but is it?

 

[RRSignal]

Trainz impresses an effective load of 300 polygons per material draw call. I've heard the draw call likened to drawing with markers or paint. You draw with a market or paint brush, but, when it comes time to change materials, there is a penalty for you putting down your marker or brush and getting a new one with the correct material applied. In your example, the mesh is 1866 polys, with 19 materials (5700/300 = 19). So, yes, that's an effective poly load of 7566.

For Sketchup models obtained from 3D Warehouse, the texture load is sometimes where the real performance destruction occurs. The meshes often have low polys themselves, but an insane number of materials used.

 

[Dinorius_Redundicus]

OK, thanks RR.

 

[Thai1On]

For Sketchup models obtained from 3D Warehouse, the texture load is sometimes where the real performance destruction occurs. The meshes often have low polys themselves, but an insane number of materials used.

I'm new to this and like many of the buildings made using Sketchup in the 3D warehouse. Is there a way to fix this problem? Can the model be rendered then edited in Photoshop to reduce the poly count?

Dave

 

[JCitron]

I'm new to this and like many of the buildings made using Sketchup in the 3D warehouse. Is there a way to fix this problem? Can the model be rendered then edited in Photoshop to reduce the poly count?

Dave

You can export the models from Sketch-up into another format and bring them into a 3d-modeling program such as Blender, or some other program that will export a Trainz mesh. I've never done it with Sketch-up, but I have done it when I made a model in Hexagon then exported it out to a 3ds which I brought into GMax to export it out into the Trainz model I wanted. I felt like I was juggling a bunch of cups and saucers as the data went in one program and out the other.

John

 

[RRSignal]

I'm new to this and like many of the buildings made using Sketchup in the 3D warehouse. Is there a way to fix this problem? Can the model be rendered then edited in Photoshop to reduce the poly count?

Dave

No. The mesh is what it is, as are the textures. It's conceivable you could combine textures into one file and make one large texture file married to a single material, but that would require remapping the mesh. Experienced content creators always try to keep textures/materials to a minimum to prevent extraneous draw calls, regardless of the program used (and I'm a late-adopter to this strategy myself! ) But that strategy is the same as you would use in Blender or whatever, and, frankly, if you're going to do that, you may as well make the model in Blender and have a more efficient model and (arguably) a much more efficient mesh-making process.

As far as 3DWH goes, while it IS theoretically possible to make a reasonably-efficient model (albeit probably not as efficient as Blender, Gmax, or 3DSMax), such models are extremely rare.