View Full Version : Large bitmaps as textures

06-20-2003, 03:24 AM
I'm trying to use the images of the earth from this site: http://visibleearth.nasa.gov/cgi-bin/viewrecord?11656
as a texture on a sphere around which things happen. I'm using the features of ClassGL to load the JPG image into a texture.

The problem is that when the image is more than 1024px on any dimension it fails to display. Is this a limitation of OpenGL or my hardware or Windows or...?

06-20-2003, 03:35 AM
There is a hardware specific limitation, and you can get it with glGetInteger and GL_MAX_TEXTURE_SIZE. If you need larger textures then maybe you can split the texture into smaller parts.

06-20-2003, 05:03 AM
Many thanks. I wondered if there was a way of using multiple small textures on a single quadric object, but haven't discovered a method of doing so yet. Can you point me to an example or tutorial please?

06-20-2003, 09:39 AM
Before you program too much you might want to check out Blue Marble Viewer. I think it pretty much does what you're trying to do....

06-23-2003, 01:42 AM
Many thanks for that link. From there I have found OpenSceneGraph http://openscenegraph.sourceforge.net/ and Demeter Terrain Engine, which looks very useful for the next stage of the project when I start to include terrain data.

Regards, Mark