Hi,

I'm wanting to generate a full chain of mip-maps right down to 1x1 so that I can get the average luminosity of my rendered scene.

How would I go about doing this in DirectX 11?

I have setup the D3D11_TEXTURE2D_DESC with the right misc flags and was wondering what mipmap levels i should use.

Does setting the mip levels to 0 create a full chain or do you have to manually set the number?

My last question is my scene is rendered in widescreen 16:9 so the texture isnt square will I be able to go as low as 1x1?

Thanks in advance

http://msdn.microsoft.com/en-us/library/windows/desktop/ff476426(v=vs.85).aspx maybe?

http://msdn.microsoft.com/en-us/library/windows/desktop/ff476426(v=vs.85).aspx maybe?

I had looked at that, the problem is I need to extract the 1x1 mipmap and send the data over to a shader. I can't figure out how to extract the mipmap. Thanks anyway!

The width and height are always halved and integer-truncated (a simple unsigned integer VAL >>= 1), then max’ed with 1 until both the width and height are 1. After that, there are no more mipmaps.


L. Spiro

Nice to know, Thanks!

the problem is I need to extract the 1x1 mipmap and send the data over to a shader. I can't figure out how to extract the mipmap.

tex2Dlod
Specify the level of the 1×1 mipmap in t.w and sample coordinate [0.5, 0.5] (t.xy = vec2(0.5,0.5);).

Or you can activate only the lowest mipmap when you set the texture.
When calling CreateShaderResourceView(),
Set D3D11_SHADER_RESOURCE_VIEW_DESC::Texture2D::MostDetailedMip to the last mipmap level (D3D11_SHADER_RESOURCE_VIEW_DESC::Texture2D::MipLevels - 1).


L. Spiro

Thanks a lot, really appreciated! I will go with the first option :)