Re: Number of mipmaps in a mipmap texture?

[Jose' C. <cru...@ce...>]

Il giorno 17/dic/04, alle 23:31, James W. Walker ha scritto:

> In ir_texture_convert_mipmap, we have:
>
> 	// Work out how many images are contained in the mipmap
> 	if (theMipmap.useMipmapping)
> 		{
> 		numImages = 0;
> 		n         = E3Num_Min(theMipmap.mipmaps[0].width, 
> theMipmap.mipmaps[1].height);
> 		while (n > 1)
> 			{
> 			n         /= 2;
> 			numImages += 1;
> 			}
> 		}
> 	else
> 		numImages = 1;
>
> This caught my attention because the subscript [1] for the height 
> seemed out of place.  But even if the width were the limiting factor, 
> the formula seems wrong.  For instance suppose we start with n = 5. 
> The first time through the loop, n becomes 2 and numImages becomes 1. 
> The second pass makes n become 1 and numImages become 2, and then we 
> exit the loop.  But numImages should be 3: sizes 5, 2, and 1.

yes, one of two is wrong
or we init numImages to 1 or test for (n >= 1)

but why we have to go down to a 1*1 texture?

Pax et Bonum

# dott. Jose' Cruanyes Aguilar  -  C.E. Soft srl
#  Pzza. Firenze,4 MILANO  -  XX Settembre 10, CREMONA
#   02,33603122                0372,460602