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View Full Version : Clipmap Problem and Freelance



Slick Systems
08-17-2009, 10:02 AM
Hi guys,

I have a small problem regarding clipmaps, don't know if anyone has experienced this before.

See the attached image and look at the people which are just flat polys with an image map as a texture and then a clipmap applied to remove the excess poly around the image.

As you can see the people have not rendered correctly the clipmap looks as though it has shifted or in some instances not worked, however in layout the preview of the scene looks fine and all the people are complete.

What's going on?

Also is anyone up for some freelance work, ideally situated in the UK in the midlands area?

eblu
08-17-2009, 01:34 PM
looks like an opengl problem.
have you considered using a transparency map (and associated spec map, to clear out any possible spec highlight)? it might not be that difficult to setup (depending on how you set it all up in the first place) and it may work around the clip map problem.

3dworks
08-17-2009, 03:26 PM
i doubt about opengl problems, because those won't affect render results afaik?!

first idea: did you use a TGA as image format, just to check if there aren't any format issues with the clip file? TGA is probably the most robust format in LW - good for checking this potential problem.

second thing: did you check if the clip map was placed correctly? are those people clipped with UV maps? if not, i would suggest to use this mapping.

hope that helps

markus

Mr Rid
08-17-2009, 03:40 PM
What I do is copy the color image texture and paste into the clip texture, then select your clip map, so you are sure the image is being applied correctly (assuming the color image appears correctly positioned and they use the same UV, etc if applicable). Then check if your clip image has an alpha channel lurking and if it is enabled/disabled in the Image Editor.

SplineGod
08-17-2009, 07:25 PM
Also try turning off pixel blending and/or mipmapping.
Anything that antialiases the clip map can mess it up since
they can only be two colors.

boomforeal
08-17-2009, 09:05 PM
Definitely check your sizings and yes Targa is the best....I've had issues in the past I think when the image and the clip map have an alpha channel....If they do, get rid of them and just import them without the alphas.

Slick Systems
08-18-2009, 01:46 AM
Right a few good suggestions there,

yes i'm using tga format images they are also applied with a UV map.

I'll double check on the alpha maps within the images just in case.

I'll let you know what happens.

Slick Systems
08-18-2009, 02:06 AM
Solved it!!

Thanks Guys, it was an alpha channel on the clipmap image combined with a strange anomaly whereby some of the clipmapped objects had mysteriously changed the image I used for the clipmap to one of it's own choosing - when I opened image editor and selected the clipmap image to see it in the small preview window it didn't display at all which leads me to think that there must have been some sort of upset with the path to the image and LW defaulted to a different image for some reason!! don't know why this would be :-\. Once I re imported the image into image editor sans alpha channel it then displayed correctly in the preview window and then I manually had to re-apply it to every instance of the clipped object in the scene.

Hope this makes sense to everyone.

Problem solved. Thanks.

Slick Systems
08-18-2009, 02:12 AM
In future I may resort to a spec/trans map because it would not require it to be duplicated across every object (over 100 in this scene and not able to multi select which is a *****) and could be controlled within the surface editor - are there any other downsides to this I am unaware of?

Unless there is a quick way of applying the clipmap to multiple objects in one stroke?

bjornkn
08-18-2009, 02:35 AM
With over 100 instances of the clip-mapped objects I would definitely use hd_Instance anyway, and that would also let you do the settings for only one (or a few) objects.
Don't you already use it for all those seats?

archijam
08-18-2009, 02:47 AM
In future I may resort to a spec/trans map because it would not require it to be duplicated across every object (over 100 in this scene and not able to multi select which is a *****) and could be controlled within the surface editor - are there any other downsides to this I am unaware of?

Unless there is a quick way of applying the clipmap to multiple objects in one stroke?

Place in modeller, and a UV map? Any reason you want to place them in Layout?

Slick Systems
08-18-2009, 03:10 AM
Archijam : not sure what you mean?

The way I setup these scenes is to model a block of seats and in this instance place a poly above a seat for the person image. The poly is UV mapped then an image of the person is placed onto it using the UV map to position. The poly is then duplicated across the seats in the block which keeps the UV map intact and once this is done the object is saved with the seats in one layer and the polys in the other.

The object is then brought into layout and the clipmap is applied to the people layer using the uv map for positioning then it's cloned to provide seating where it's needed.

The problem occurs when you need to change the clipmap or some other attribute of that object - that's when you need to do manual messing around and with over 100 instances of the people object (potentially) it can become a tedious task.

My suggestion about spec trans maps is simply that instead of having to worry about altering every 'object properties panel' - 'cipmap texture' for every people object you can simply control all of the objects at once by their surface which is the same across all the people polys if you are managing surfaces by scene of course rather than by object.

Hope this makes sense.

Slick Systems
08-18-2009, 03:14 AM
Bjornkn : HD_Instance is unfortunately not something I have, as explained above I just use blocks of seats and clone them in layout. to get what I need.

I'd love to have HD_Instance and have looked into it several times but I just don't have the budget for it. I did email Happy digital as a few people have posted on these forums about HD_Instance not working with LW9.6 and they responded saying it works fine and there are no reported problems.

bjornkn
08-18-2009, 04:22 AM
I have no problems using hd_Instance with LW9.6
If there ever was a good use for hd_Instance it would be for your seatings. It could probably save you hundreds of work (and render) hours?

Mr Rid
08-18-2009, 02:55 PM
HD Instance and 9.6..... Same here - working fine with no problems.

Several people reported that HDI.2 was rendering black instances with radiosity.

Mr Rid
08-18-2009, 05:02 PM
Hmm, wildr3d reports that GI scenes work in 9.3 that dont work in 9.5 or 9.6.

And it seems Graham is off vacationing with Cantarcan. :D

Mr Rid
08-18-2009, 09:49 PM
Well... adding a light for the instances works fine for us. It "may" not work as it's supposed to, but at least it's working enough to get by.

Am not sure where the issue is. Do you only see a problem with HDRI, what about a jpg? What if you have an environment sphere around your scene with no lights? And do backdrop colors trace with no lights?

Slick Systems
08-19-2009, 01:45 AM
I did a little searching on the net about HD instance with 9.6 and it appeared that some people had experienced crashing issues with it in 9.6 and they posted on these forums so I thought I'd just clear up any rumours regarding this with a direct email to Happy digital themselves.

Simply put their response was conclusively that there was no problems at all.

I'll definitely look into HD instance again and see if the powers that be will grant a boon this once!! :-).

Cheers guys.

archijam
08-19-2009, 01:56 AM
No problems with HD-I 1.82 here on 9.6 UB.

Mr Rid
08-19-2009, 02:38 AM
I did a little searching on the net about HD instance with 9.6 and it appeared that some people had experienced crashing issues with it in 9.6 and they posted on these forums so I thought I'd just clear up any rumours regarding this with a direct email to Happy digital themselves.

Simply put their response was conclusively that there was no problems at all.

I'll definitely look into HD instance again and see if the powers that be will grant a boon this once!! :-).

Cheers guys.

Um, 'There are no problems' does not clear up the issue. I have not read rumours but rather experiences of users, and have not read anything about crashing but rather that something is awry with HDIv2 and rendering GI in LW9.5 and 9.6 that does not occur in LW9.3, or with HDIv1. And I have read that several users, and Pixel Magic and Rhythm and Hues could not get a response from Graham Fyffe for several months.

I wish I had HDIv2 to test, as I have not read of anyone pinning down what is going on yet.

Slick Systems
08-19-2009, 02:53 AM
Hi Mr Rid,

Sorry I didn't mean to belittle your problems I was merely making clear that I have asked the question of Graham and he responded within the day saying that HDI2 works fine with LW 9.6UB on the mac.

I like yourself have read other users posts on these forums about issues with HDI2 and 9.6 and I wanted Graham to reassure me that there were no issues that they knew of before I considered purchasing HDI2.

The problems I had read about involved a crash when HDI tried to generate the instances at render time (forgive my limited knowledge of this issue as I have never used the plugin and do not know how it works), the crash seemed to be caused by HDI.

Regarding your issues of not rendering under GI situations I cannot comment as I have never used the plugin. Perhaps starting a new thread in the mac forum may reveal other users problems with this plugin.

Sorry.

bjornkn
08-19-2009, 04:59 AM
That black GI rendering may be a Mac-only problem?
I can light a scene with only a HDR, and hd_Instance objects renders just fine.
The same happens with just a non-black background too - it still renders fine.

What you have to remember though is to set GI to use volumetric radiosity!
If you don't do that LW will of course render them black, just like it would render the entire scene black with GI off, when there are no lights there.

Could those "bug reports" be caused by forgetting to turn Volumetric radiosity ON?
Or is it a real problem?

Edit: Added a few examples, lit with a blurred HDR, no lights and no ambient.

Slick Systems
08-19-2009, 05:03 AM
Could those "bug reports" be caused by forgetting to turn Volumetric radiosity ON?

That there could be the culprit by the sound of it.

bjornkn
08-19-2009, 05:28 AM
Here's another one where the scene is lit by the same HDR applied to the inside of a sphere. The luminance is set to 200% here - hence the difference from the first one.
No other lighting, and no Textured environment.

Slick Systems
08-19-2009, 06:56 AM
Looks good to me Bjornkn, I think you were right.

Mr Rid
08-19-2009, 04:43 PM
Hi Mr Rid,

Sorry I didn't mean to belittle your problems ...

Sorry.

I did not feel belittled, but rather that after several users reported a problem, a support announcement of 'there are no problems' is just comical.

I dont have HDI2 to test. But yes, enabling Volumetric Radiosity was the problem. I see that VR defaults to being enabled in LW9.3 when GI is enabled, but VR defaults to disabled in LW9.6 (I assume LW9.5 also), thus it appearing that something broke with an update.

Slick Systems
08-20-2009, 02:03 AM
Hi Mr Rid,

I'm happy that the problem has now been solved and hopefully anyone else who has this problem will now be aware of it. (I think belittled was the wrong word - I blame my poor grasp of the english vocabulary :-).

Perhaps NT decided that it should be left to the user to determine if they want VR on or off and therefore changed the default setting in later versions? rather than just enabling it by default, with my very limited knowledge of VR perhaps it eats render time and thus was deemed to be better off and only switched on when it was absolutely necessary.