[Intel-gfx] OpenGL sampler objects on sandybridge with Ubuntu Linux 12.04

[Daniel Vetter]

Hi,

Please file a bug report with the below details on bugs.freedesktop.org
against "Mesa" -> "DRI/Intel(i965)".

Thanks, Daniel

On Wed, May 16, 2012 at 09:58:45AM +0000, Mark Newiger wrote:
> Hello,
> 
> We are using an MiniPC with the following configuration:
> 
> -          Intel SandyBridge PC Mainboard DH61AG and integrated Intel HD Graphics 3000
> 
> -          Dual OS: Windows 7 32bit and Ubuntu 12.04 32bit
> 
> When using OpenGL sampler objects for configuring textures, on Ubuntu I have to create a mipmap chain by calling "glGenerateMipmap()". Otherwise the texture sampling will not work (e.g. returns black).
> Take the following example:
> // Init
> int texture;
> glGenTextures(1, &texture);
> glBindTexture(GL_TEXTURE_2D, texture);
> glTexImage2D(...);
> 
> int sampler;
> glGenSamplers(1, &sampler);
> glSamplerParameteri(sampler, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
> glSamplerParameteri(sampler, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
> 
> // Render loop
> glActiveTexture(GL_TEXTURE0);
> glBindTexture(GL_TEXTURE_2D, texture);
> glBindSampler(0, sampler);
> ...
> 
> This works perfectly on Windows but not on Ubuntu. For Ubuntu Linux I have to add the following:
> //Init
> ...
> glTexImage2D(...);
> glGenerateMipmap(GL_TEXTURE_2D);
> 
> Without the mipmap the texture sampling does not work, although I am not using any mipmaps.
> When using the traditional texture filter configuration, this problem does not occur and the code behaves the same on Windows and Linux:
> // Render loop
> glActiveTexture(GL_TEXTURE0);
> glBindTexture(GL_TEXTURE_2D, texture);
> glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
> glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
> 
> Seems to be a driver bug for me. Or did I oversee something ?
> 
> Thanks and best regards
> Mark
> 
> 
> Best regards,
> Mark Newiger | Senior Software Engineer
> SeeFront GmbH
> Esplanade 41 | D-20354 Hamburg, Germany
> Office: +49 40 416 22 64-83
> mark.newiger at seefront.com<mailto:mark.newiger at seefront.com> | www.seefront.com<http://www.seefront.com>
> 
> Managing Director: Christoph Grossmann
> Registered seat of the company: Hamburg
> Register Court: Amtsgericht Hamburg HRB 98205 VAT-ID-No. DE248406189
> 

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-- 
Daniel Vetter
Mail: daniel at ffwll.ch
Mobile: +41 (0)79 365 57 48