Imagination PowerVR SDK Blog

NavDataTools missing OGLTools

pvrtextool

#1

I'm trying to use your NavDataTools from the 2.10 SDK Utilities with NAVTEQ ECM but there is very little documentation it seems.

When opening the Visual Studio solution it appears the OGLTools project is missing and it just won't compile. Is this an intended omission?


#2

Hi Slion,

thanks for letting us know!
No, this is not intended and we are working on a fix.

Thanks,
Marco




#3

Thanks Marco. Do you also have a short description of the process to convert ECMs? That would save us a lot of guess work.

Before noticing the NavDataTools I managed to render an ECM city tile using the POD player after passing it through Collada2Pod. I had to disable the FX though to get it to display anything, only flat and wireframe render would work even though the converted texture were loaded properly. With FX enabled I'm getting only blackness for some reason.


#4

Ok I found my problem with the textures. When converting the PNGs I did not specify the -m flag for mipmap generation. On top of that your framework does not ever use glGenerateMipmap but in my case still ends up using some texture parameters mipmap options even though the texture does not actually have mipmaps. For me it would result in a totally black render.

I could swear there is something fishy with either the PVRTexTool our the way the framework manages pPFXTex->nMIP flag.

I was using OGL8888 to convert the PNGs without the -m flag. Using the -m flag fixes my issue. I did not double check it but I guess if you'd use textures without mipmap and override the _MIPMAP_ texture parameters or use glGenerateMipmap it would fix it too.


#5



Hi Slion,

have you read the "3D Navigation Rendering Techniques" whitepaper that comes with our SDK. There is a description of the Collada->POD conversion process and the command line that has been used in there.
(https://www.imgtec.com/powervr/insider/docs/PowerVR.3D%20Navigation%20Rendering%20Techniques.1.8f.External.pdf)

glGenerateMipmap doesn't work on compressed textures, that is why we choose to store the individually compressed MIP levels and setup the texture with the corresponding filtering modes.
If you are using OGL8888 textures glGenerateMipmap should work as expected.

Regards,
Marco





marco2012-03-30 15:36:03