I'm not sure if this is the best way (or even a good way) but I have done something similar by loading only a small (2^2, 2^3) transparent texture then making calls through to Java to load a texture when a particular trackable is in view.

The transparent texture makes sure there are no crashes in JNI involving missing textures while the other texture is trying to load.

Rob.

Could you give me some code or sample about loading texture from database because my project looks like your project. My project is about rendering 3D model from database when the frameMarker is detected. Thank you .

Hi,

it should be perfectly possible to retrieve images from a database and generate a texture out of it;

for the DB part (how to store/retrieve images to/from a database), that's pretty much an Android specific question (not Vuforia related), so you may want to check the Android developer guide for it; in general in Android you can access DB using Content Providers for SQL Lite (but there may be other options as well):

http://developer.android.com/guide/topics/providers/content-providers.html

This forum thread is addressing this topic, as it provides code specifically for storing/retrieving Botmaps to/from a DB:

http://stackoverflow.com/questions/6279940/creating-database-in-android-which-stores-image 

Once you have handled the Bitmaps loading from a DB, you will need to generate your OpenGL on-the-fly  textures, using pretty much the same code that you can find in the initRendering function in ImageTargets.cpp; however you will need to put that code (glGenTextures etc..) in your _renderFrame() function, so that you can do the texture creation on the fly when needed (i.e. whenever there is a new Bitmap available)

IHTH.

So sorry AlessadroB

I forgot to tell you that my project is on iOS not Andriod. Do you know how to solve this problem on iOS? I use FrameMarker so that the data for FrameMarker is already store in Apps. When the FrameMarker is detected, I would like to render the 3D Model(.h file) from server.  Are there anyway to solve this problem without using The Unity and How ? 

Thank you again for helping :)

No problem gun0051,

that should be perfectly possible on iOS too; however I would invite you to create a new Thread and post this question on the iOS section of this Forum, as here it is Android specific.

You will get prompt reply there.

Thanks.