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View Full Version : how to load a 32mb picture



meghnath
12-23-2004, 10:40 PM
i've tried to load it, but only what i can see is a white window.
please help

Silkut
12-24-2004, 02:37 AM
Is your picture a power of two ? (such as 256*256)
Have you check the channel alpha ?
What's your method to load this ? And what's the format of your picture ?

HairyFotr
12-24-2004, 06:13 AM
If it is the right size, maybe its too big for your graphic card.
A good way to check is the Delphi3D (http://www.delphi3d.net/) s GLInfo that you can find at 3D hardware info.
Check the implementation specifics in the program and Max texture size.

12-25-2004, 02:38 AM
The above answers are both correct, but please allow me to elaborate on them a bit.

There are some constrains in the classic OpenGL in regards toward the dimension of a texture.

The texture width and height need to be a power of two value. So vaild textures sizes are for example 1024x1024 or 512x128 and so forth. Unfortunatly there is a maximum width and height that depends on the underlying hardware you use. Common hardware restrictions are 2048x2048 and 4096x4096 maximum.

If you have a texture that is bigger then this you need to split it up into multiple textures and use the texture border to "stich" them together on the screen.

if you have a texture that is smaller then the maximum allowed size but doesnt have power of two dimensions you can place the texture into a bigger texture that obeys to the power of 2 restriction. Of course you need to adjust your texture coordinates too.

If you are ready to use extensions, you can also use the texture_rectangle extension to ease up your life.