Texture MipMaps

[SpiderPig]

I've started creating a large texture atlas for my terrain so that I can use more textures with less slots.  The problem is the default mip-map generation creates bleeding on lower mip levels, and from what it says here, I need to create each mip-map separately and then combine them.  Does anyone know of a way to manually set each mip-map level into a texture?

Can I perhaps make a .dds texture with the mip-maps I want and will the editor then convert it to .tex format using those mip-maps?

[Josh]

Yeah, it looks like you could make your own DDS file and the mipmaps would be retained when converted to TEX.

[SpiderPig]

Awsome thanks ?

[SpiderPig]

The .tex files doesn't seem to retain the mipmaps in the .dds file.  I've attached the test files I used.  Also I used this code to extract the mipmap level then later draw it to the screen;

//On Load
Texture* t = Texture::Load("Terrain/Textures/beach_dirt_b.tex");
char* buffer = new char[t->GetMipmapSize(1) * 4];
t->GetPixels(buffer, 1);
Texture* tex = Texture::Create(t->GetWidth(1), t->GetHeight(1));
tex->SetPixels(buffer);

//On Run
context->DrawImage(tex, 100, 100);

Here is what the second mipmap should like;

 

 

 

Using gimp to load and edit the dds file, I can see that it is defiantly saving the second mipmap with the edit I did.  It just not showing up in the conversion to tex.

Is it possible to add a command to the texture class; SetMipMap(Texture* texture, int level)?  Provided of course it has the right resolution for that level...

beach_dirt_b.tex

beach_dirt_b.tex.meta

beach_dirt_b.dds

[macklebee]

I wonder if its due to the default settings for the editor when converting an image to TEX that it automatically saves it as DXT1 and with the 'Generate Mipmaps' option selected? Is it overwriting your mipmaps because of this? These have always been settings i wish we had control over instead of them just being hard-written as the defaults.

[SpiderPig]

I think it might be.  I just tested it again and this time exported the dds with only 5 mipmaps.  After converting to TEX and loading in game the mipmap count was at 10.  It would be nice to have more control over the import settings.

[macklebee]

Just a quick and dirty script to view the mipmaps saved inside a TEX file:

window = Window:Create("texture detail example",0,0,800,600,Window.Titlebar+Window.Center)
context = Context:Create(window)
world = World:Create()
camera = Camera:Create()
tex = Texture:Load("Materials/beach_dirt_b.tex")
mips = tex:CountMipmaps()

while window:KeyDown(Key.Escape)==false do
	if window:Closed() then break end
	
	Time:Update()
	world:Update()
	world:Render()

	context:SetBlendMode(Blend.Alpha)
	for i = 0, mips-1 do 
		Texture:SetDetail(i+1)
		if i <= 4 then 
			context:DrawImage(tex,155*i,150,150,150)
		else
			context:DrawImage(tex,155*(i-5),305,150,150)
		end
	end
	context:DrawText("Number of Mipmaps: "..mips,2,2)
	context:SetBlendMode(Blend.Solid)
	context:Sync(true)
end

[Josh]

Okay, so the way Leadwerks supports DDS is it just loads it with FreeImage and regenerates mipmaps.

Here is a little program you can use to convert a DDS into a TEX file and save the same mipmap data.

dds2tex.zip

Just drag the DDS file onto the EXE and it will convert it.

[macklebee]

hmmm. This still seems to be saving the same way as the Editor does where it overwrites the existing mipmaps. I am not seeing a difference when viewing with the above program. The second mipmap should look like this:

[Josh]

I will check this out. I looked at the source code and it does read the DDS mipmaps and write them out, I thought.

[SpiderPig]

I tried the converter on my DDS that has only 5 mipmaps and got this when loading into the editor.  So I guess it's trying to calculate them still...?

Error: Texture mipmap count (5) does not match calculated mipmap count (10).
Error: Failed to load texture "G:/Leadwerks/Projects/TestingGrounds/Materials/beach_dirt_b.tex"

 

As a general rule are all mipmaps supposed to present?  Right down to the lowest size? (2x2 or 1x1)?

[Josh]

Should be mipmap-complete, down to 1x1.

[SpiderPig]

Any idea when this could be fixed?

[Josh]

If the DDS only contains five mipmaps it will not work. Textures must be mipmap-complete. The way you calculate this is to keep dividing the width and the height until they both equal 1.

[SpiderPig]

Okay, I got it working with the tool you posted thanks.