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Guest christian

Hypothetical question.

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I'm about to start modeling a large land grant university where virtually every building is built of red brick with orange tile roofs. Would it be easier on the frame rate to carve the buildings into small polys and have one or two generic textures or leave the buildings basically boxes and have different texture files for each one.

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Definitely much better for frame rates to use as few different textures as possible. You might even want to consider creating some generic building blocks as library objects, and then use the objects with simple library calls to create the individual buildings.The other thing that will optimise the frame rates is to use the new floating point commands, either by designing your 'building blocks', or the complete buildings, with gMax (the easiest way at present) or by hand coding with SCASM (tricky and long-winded at the moment). But before very long I think there will be some other design tools you can use too.Hope this helpsGerrish

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Low polygon count models will be the framerate friendly choice! Ie use the boxes and put textures on them...You can see this trend in computer games. In old computer games 3D models are always chunky and not very detailed, but newer games have far more detailed models. This is the reason why phototexturing is used so often. It's much better to depict the detail of an object with textures than with a high number of polygons. Same reason why we have bump mapping. With bump mapping a texture is used to calculate light effects rather than calculating the light with raytracing on a high poly count object...Hope that helps...Cheers, Christian

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Let's be clear about this. As we all know, loading another texture from disk is far more costly to execution time and frame rates than drawing some extra polygons. Although it is true that the texture only has to be loaded once, whereas the polygons are redrawn for every frame displayed on screen, the time to load the texture is thousands of times greater than drawing some polygons. This is one of the basic principles of the way that gMax is designed to work - and I think we all agree that gMax is an excellent, industry-standard, tool that produces quick models, despite the number of polygons!Of course the quickest models of all use photographic texturing and very simple shapes, with the texture depicting the detail, but where it is a choice between between using just a few textures and some extra polygons, or more textures and fewer polygons, then 'fewer textures' wins hands down! And this too is part of the normal design approach in gMax.What I am suggesting, Checkmate, is that you break your buildings down into generic, phototextured, building blocks, and put the building blocks together to create complete buildings. Then put your roof on top using the same generic texture every time, not have a separate texture for each building. The point that Christian is making, quite rightly, is that you must keep the shape of your models simple and use photo-texturing for the detail. Don't, for heavens sake, try to draw each little door, window, eaves, gutter and downpipe with separately-textured materials like one designer I came across, who wondered why he was getting slow frame rates when he was detailing each separate downpipe on his hangars and each individual girder on gantries, power pylons, etc.CheersGerrish

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Hi Gerrish's points are right on improper use of texture will kill you FAR sooner that poly's will One thing I might add that if you aredoing buildings with a fairly complex shape then make them from extruded splines(I.E. draw 'em as "outlines") and then extrude them.The reason for doing objects from splines is simple you have FULLcontrol over how many poly's are created once you extrude your mesh.I will post a pic of a building that looks high polly but is not(it has 181 poly's) like Gerrish said it's all in the textures. Oneother thing to try when makeing you textures is to use what are known as cram textures I.E. a single .bmp with several textures inside it. I hope the above is of some help Dan

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Here's an example of what I'm talking about. This is Mackey Arena at Purdue University. The model has about 200 rectangles. If Gmax produce 2 triangles for every rectangle then about 400 polys. Obviously because of the repetitious nature of the building I could have done this with about 1/4 the texture space but the polys would be in the thousands. I could then use the extra texture space for nearby buildings,Is it better to hack the buildings into smaller polys or is this a good compromise?

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Also, whats up with the little black lines between the textured polys? it seems to be the worst on the outside of verticle corners especially when I try to line the texture up to the pixel the best.I look back at the little house I built in the tutorial and they aren't there. Guess it's time to reread the tutorial.

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This is the right approach. Personnaly, I'd even decrease the polycount even more, and use more textures, but that's where it's getting a bit personal taste really... At some point it comes down to other variables, such as what hardware you are using, and how the many other objects there are in the same region...Cheers, Christian

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Hi there "Checkmate" how are you maping your textures? I.E. planar,box etc you probably know this but it does make a differance in whatprojection type you are using ,also the angle of projection oftenmakes a diff as well. One other thing make sure that NONE of the "background" from Photoshop gets into your final texture it's easy to miss a single row of pixels!. Dan

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Actually this is my first GMax project so I'm still learning. I rather thought that once you started unwraping the uvw map that setting was not that important. Changing it after you've put time in changing the mapping has catastrophic results.

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Dear Checkmate:I had that trouble with a big building divided in 4 polygons by floor, i get black lines between some polygons.I know that Gmax objects mix the selected pixels with the no selected pixels of textures, and Gmax mix the opposed texture edges, for example if the right edge of your texture have a black line (Vertical), the left egde of your texture will have a little black border .I have had to return to FSDS 1.6 to make my building without texture problems in my building, and with the same quality.Thanks.Alfredo Mendiola LoyolaLima Peru

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