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Re: glTexSubImage2D, Leopard


On 27 May 2008, at 12:53, loMadi wrote: 
Hi,

when updating an Alpha texture with glTexSubImage2D there are some
strange effects (the right most columns are updated wrong).


glTexSubImage2D(GL_TEXTURE_2D,
		0,	// level
		0,	// xoffset
		0,   	// yoffset
		258,    // width,   it woks for 256, 260, etc but not for 258!
		258,	// height,  it woks for 256, 260, etc but not for 258!
		GL_ALPHA, // format
		GL_FLOAT, // type
		(GLvoid*)sourcePointer);



does not work!

What format is your texture defined as (i.e. the internal format in the original glTexImage2D). Are they float textures or straight 8 bit components?
Does the height parameter really make a difference? You description would suggest no, but your comments say yes.
Do you see the same on the left side if you change the offset?

If you are using 8-bit textures, then I wonder if you might have more luck if your texture data was passed as 8-bit values rather than floats. If that works I think you've found a bug. (glTexSubImage updating 32-bit value based on input format rather than texture format)

BTW If you are using ARB_TEXTURE_FLOAT, it probably a safe bet to use ARB_TEXTURE_RECTANGLE to do NPOT textures.
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 >glTexSubImage2D, Leopard (From: loMadi <email@hidden>)



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