RE: [oglbase-discuss] question on multitexture spec

[Michael I Gold]

I believe they are equivalent, yes, assuming nowhere else in the code is a
texture object other than 0 bound to either texture unit.

> -----Original Message-----
> From: Srinivas Dasari [mailto:[EMAIL PROTECTED]]
> Sent: Wednesday, May 23, 2001 9:39 AM
> To: [EMAIL PROTECTED]
> Subject: [oglbase-discuss] question on multitexture spec
> 
> 
> Hi
> 
> I have the following question on the multitexture specification.
> 
> Consider the following two code cases.
> 
> case 1:
> 
>       glActiveTextureARB(GL_TEXTURE0_ARB); 
>       glBindTexture(GL_TEXTURE_2D, 0);
>       glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, W, H, 0, 
> GL_RGBA, GL_INT, Img0);
>       glEnable(GL_TEXTURE_2D);
> 
>       glActiveTextureARB(GL_TEXTURE1ARB);
>       glBindTexture(GL_TEXTURE_2D, 0);
>       glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, W, H, 0, 
> GL_RGBA, GL_INT, Img1);
>       glEnable(GL_TEXTURE_2D);
> 
> case 2:
> 
>       glActiveTextureARB(GL_TEXTURE0_ARB);
>       glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, W, H, 0, 
> GL_RGBA, GL_INT, Img0);
>       glEnable(GL_TEXTURE_2D);
> 
>       glActiveTextureARB(GL_TEXTURE1ARB);
>       glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, W, H, 0, 
> GL_RGBA, GL_INT, Img1);
>       glEnable(GL_TEXTURE_2D);
>       
> 
> My question is, are these two cases equivalent?
> In case 1, the units 0 and 1 are explicitly bound to default 
> texture object 0.
> Is this binding implied in case 2, even though glBindTexture 
> is not used.
> 
> Since all texture units are bound to default texture 
> object(which is 0)
> during initialization (according to the spec), I think, both 
> units, in both 
> cases only see Img1 and NONE of them will see Img0. 
> Is this the correct interpretation of the spec?
> Is case 2 any different from case 1?
> 
> -Thanks for any info...
> -Srinivas
> 
> **********************************************************
>               Srinivas Dasari
>               Sun Microsystems
>           Phone: 650-786-6603 (Off)
> **********************************************************
>