Results 1 to 9 of 9
  1. #1
    Join Date
    Feb 2004
    Location
    Grimsby, Ontario
    Posts
    22

    Converting High-poly objects to low-poly ones.

    Does anyone know a good way to convert a high-poly mesh down to a size that's acceptable for UT2k4?

  2. #2
    Join Date
    Mar 2004
    Location
    Netherlands
    Posts
    491
    it depends on what you mean at high poly, it would be usefull wenn you also say what kind of on object or something it would be and what will you use it for. because not everything is or has 2 be the same poly's. a way 2 convert is just 2 remoddel it and try 2 get the unneccesary poly's away whatout messing up the shape. it's not an easy job, but it will be a lot easier then remoddeling it from scratch. but that also depends on what it is. and it's handy 2 tell us what you mean at high poly???? how many poly's does it allready have???

  3. #3
    Join Date
    Sep 2003
    Location
    Beaverton, Oregon
    Posts
    163
    If there is an automated way of doing this I would love to hear about it. I model in 3DS Max (haven't learned Maya yet just downloaded PLE).

    I did this by hand in max and it was very time consuming. I found areas where I didnt need detail and welded vertex's together. Keep an eye on your shaded model while you are doing this.

    I want to find a "Simplify" or "Reduce PolyCount" plugin.

    ~Billkr

  4. #4
    Join Date
    Apr 2004
    Location
    Canberra, Australia
    Posts
    27
    there is an 'optimise' modifier in 3DS. it's worth having a play around with. if you put a selection modifier on your object, you can select the area you want to optimise. using this, you can optimise one area severely and leave others intact or optimise them to a lesser extent.

    the options (to the best of my knowledge)

    I'm not sure what the 'level of detail' radios do

    Face threshold (value as X) - if 2 polys are at an angle of <X to eachother, max will make them 1 polygon. with groups of polygons joined incrimentally with an angle <X, but adding to an angle >X, it seems to guess which ones should go together. I'm not sure of this, but it seems to be along those lines.

    Edge Threshold - i never touch this (i'm not sure what it does)

    Bias - seems to determine how much of the original shape is maintaned. the higher this is the less the optimiseation will do. i generally leave this at 0.1

    Preserve Material Boundaries - selecting this option will (for the most part) keep your UVW maps intact. to be honest, it's probably better to redo your UVWs because even if this option is selected, the modifier still tends to strech the material. also, if you have this selected your optimisation won't be as comprehensive.

    Preserve Smooth Boundaries - this option will preserve the smoothing groups of an object so ajoining polys with different smoothing groups will not merge. If you put the 'face threshold' high enough it may override this option. I'm not sure

    Update - use this option if you have a really big mesh - it just means that the viewports wont update as you change the sliders.

    -----

    i hope that made sense. there were a lot of 'i'm not sures' in that, but i think what i said was generally correct...

    anyway. the optimise modifier is a good place to start if you want to convert a high poly object quickly, but if you want a really slick job, it's probably better to remodel it from scratch,

  5. #5
    Join Date
    Apr 2004
    Posts
    9
    To fill in what cellfor was missing, these are the options in the Opimization rollout.

    Level of Detail group
    Renderer L1, L2—Set the level of display for the default scanline renderer. Use Viewports L1 and L2 to change the stored optimization level. Default=L1.

    Viewports L1, L2—Set the optimization level for both viewport and renderer. Also toggles the level of display for the viewport. Default=L1.

    Optimize group
    Adjusts the degree of optimization.

    Face Thresh—Sets the threshold angle used to determine which faces are collapsed. Low values produce less optimization but better approximations of the original shape. Higher values improve optimization, but are more likely to result in faces that render poorly (see Bias). Default=4.0.

    Edge Thresh—Sets a different threshold angle for open edges (those that bound only one face). A low value preserves open edges. At the same time you can apply a high face threshold to get good optimization. Default=1.0.

    Bias—Helps eliminate the skinny or degenerate triangles that occur during optimization, which can cause rendering artifacts. Higher values keeps triangles from becoming degenerate. The default of 0.1 is enough to eliminate the skinniest triangles. Range=0.0 to 1.0 (a 0 value turns Bias off).

    Max Edge Len—Specifies the maximum length, beyond which an edge cannot be stretched when optimized. When Max Edge Len is 0, it has no effect. Any value greater than 0 specifies the maximum length of the edges. Default=0.0.

    Along with Bias, this control helps you avoid creating long skinny faces while optimizing.

    Auto Edge—Turns edges on and off following optimization. Turns on any open edges. Turns off any edges between faces whose normals are within the face threshold; such edges beyond the threshold are not turned on. Default=off.

    Preserve group
    Maintains clean separation at the face level between material and smoothness boundaries.

    Material Boundaries—Prevents face collapse across material boundaries. Default=off.

    Smooth Boundaries—Optimizes an object and maintain its smoothing. When turned on, allows only faces that share at least one smoothing group to collapse. Default=off.



    As you can see by them, you can have a good deal of control over what the modifier changes to the structure of your model.

  6. #6
    Join Date
    Apr 2003
    Location
    Heavens above
    Posts
    357
    Checkout the MultiRes modifier. That's made for recuding polygon counts. It's tricky to get a good result but it's a good starting point.

  7. #7
    Join Date
    Feb 2004
    Location
    Grimsby, Ontario
    Posts
    22
    I was thinking along the lines of having a mesh that's around 10k polys and getting it down to 2k or so. I was wondering if there would be a point in creating that first mesh in the first place, or if I should just focus on faking the detail with textures right away.

    I find optimise does get rid of wasted polygons, but that doesn't help if your mesh is detailed enough to need 'em!

  8. #8
    Join Date
    Feb 2004
    Posts
    7
    Well doing it manually gives you the most control.

    Start merging polygons, I don't use max so I can't help you with that part exactly (nor do I know what the function is called in max)

    But I recently reduced a high poly 80k poly model into around 4k, after deleteting and remodeling the areas that would be too hard to optimise with this method I did the rest all manually.

    Just start from one end and start looking at where you could remove polygons but keep the basic look, you'll most likely end up with a model nearly the same detail but much lower polycount.

  9. #9
    Join Date
    Mar 2003
    Posts
    226
    Use Rational Reducer!.......fior Max user get Polygon Cruncher...

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •