Details from Rhino developer Jeff LaSor

It is incorrect to think that larger resolution images will provide more

detail in Rhino's OpenGL modes...Why? Because OpenGL has 2 limitations:

    1) Bitmaps must be a power of 2 in both width and height
    2) Textures have limitations on what their size can be, based on your video card and driver.

Given those 2 things, here's what Rhino MUST do if either of these (or both)

are not satisfied:

• 1) Rhino must resize the image (either upwards or downwards) so that the

width and height are both powers of 2 (2, 4, 8, 16, 32, 64, 128, 256, 512,

1024, 2048, 4096, etc...).

• 2) Rhino must resize the image (downwards) to a power of 2 if the current

image resolution is greater than that supported by the card/driver.

If this isn't done, then the image will not display at all.

Having said that, I strongly recommend you try resizing your images manually

to match the criteria I've outlined above, so that Rhino won't touch them at

all...and theoretically, they should display exactly the way you would

expect them. Depending on your video card, I wouldn't go any higher than

2048x2048...most mid-range and higher cards support at least that...The next

beta will have this information in the OpenGL options page so that you can

see what your card's limits are...but for now, try sizes less than or equal

to 2048 and see if things look any better.

Please remember, just because you load an image that is 1000000 x 1000000,

doesn't mean that's the resolution Rhino is using (for the reasons I've

stated above)...so you might feel that 2048 is too small to get the details

you want...but again, if 2048 is your card's limit, then that's what size is

actually getting used anyways.