Terrain is "split" in samples

harmon · Post by **harmon** » Fri Mar 11, 2005 2:47 am

I don't think that i noticed this when running OGRE in windows, but in linux the terrain in the samples is split. At seams you can see through the terrain. Is this just a problem I am having? What can i do to solve the problem. If you don't know what im talking about ill post a pic.
Thanks.

neocryptek · Post by **neocryptek** » Fri Mar 11, 2005 3:14 am

I believe this is(was?) a problem with ATI's opengl drivers. I dont have an ATI card so not positive on that.

Do you have the latest drivers? Does it work in directx? Howabout opengl on windows?

Putting in too extreme values for certain options in the terrain.cfg file can also show this, have you modified it?

-N30

harmon · Post by **harmon** » Fri Mar 11, 2005 3:28 am

yes, I do have an ATI card and the latest drivers but I dont remember if I was doing directx or opengl in windows, but i do know i didnt see the split in windows. I also have the latest linux drivers (actually not the LATEST, but still very recent) for ATI. I guess i just have to wait till newer/better drivers come out. Also, I did not modify the terrain.cfg file.

harmon · Post by **harmon** » Fri Mar 11, 2005 7:59 am

you know, the funny thing is that I was messing with the wireframe option just for fun and noticed that when the terrain is updating itself to be more detailed, the portion of the terrain being updated "pops up" a little causing the terrain to either become segmented or to come back together... I figured this out by switching between wireframe and normal at a fast pace. Does this really have anything to do with it? any more ideas on this?

Lodes · Post by **Lodes** » Fri Mar 11, 2005 8:12 am

This is a known bug when using the opengl renderer. I can't find the other posts detailing the problem and possible causes. I don't remember what was said.

Post by **tuan kuranes** » Fri Mar 11, 2005 8:39 am

Disable Lod vertexmorphing in Opengl with Ati. (at least on win32, don't know about linux ati opengl)

harmon · Post by **harmon** » Tue Mar 15, 2005 2:21 am

An update to this: I updated my linux ati drivers from 8.8.25 to 8.10.19 (the latest i believe) and the rendering issue still exists. Im not sure how to disable LOD vertexmorphing withn the ATI drivers either. Any ideas on this? also, wouldn't that provide for less detail in terrains by forcing them to the lowest detail at all times if LOD vertexmorphing is disabled (thats what it sounds like anyways)? Thanks all.

neocryptek · Post by **neocryptek** » Tue Mar 15, 2005 2:33 am

harmon wrote:An update to this: I updated my linux ati drivers from 8.8.25 to 8.10.19 (the latest i believe) and the rendering issue still exists. Im not sure how to disable LOD vertexmorphing withn the ATI drivers either. Any ideas on this? also, wouldn't that provide for less detail in terrains by forcing them to the lowest detail at all times if LOD vertexmorphing is disabled (thats what it sounds like anyways)? Thanks all.

Just disable it in the terrain.cfg file. LOD will work fine, it just wont interpolate between LODs smoothly, instead it will 'pop' between LOD levels.

terrain.cfg wrote:# Use vertex program to morph LODs, if available
VertexProgramMorph=yes

Thats the option your looking for.

-N30

harmon · Post by **harmon** » Tue Mar 15, 2005 10:23 pm

yes, that suggestion helped wonderfully. Thank you. However, you are also correct in that there is a "popping" action when the terrain goes into higher detail. I wonder how long it will take ATI to fix this issue... thanks again...

Post by **:wumpus:** » Wed Mar 16, 2005 12:44 am

Very long, I've spotted and reported so many ATI linux issues (especiallly in their vertex shaders implementation), some a very long time ago. Only some have ever been fixed. Linux and OpenGL in general are no priorities for them.
Get a NVidia card if you want 3d fun instead of 3d trouble under linux.

harmon · Post by **harmon** » Wed Mar 16, 2005 7:24 pm

yeah, ive heard that before, but it actually seems that of late ATI is updating their linux drivers more frequently. Hopefully they will continue to do so to get to the level of Nvidia. Unfortunatley, i cannot swap out vid cards in my laptop... we can only hope...and wait.