Making 24 bit heightmaps

I am just wondering if anyone has any good ideas on how to make 24 bit (or 32 bit)heightmaps.. that is using the rgb channels for the heightdata instead of just a greyscale heightmap..

I have had some success using various software like World Machine, Terragen, etc.. but its diffcult to get a very smooth gradients even from here..

why? and how?

because 8-bit heightmaps limit you to 256 different heights, which results in jagged slopes on hi-poly terrains.

in MED you get to set the influence of each colour channel on the heightmap (if i remember correctly... i haven't used it in a while). u could have red * 1, green * 256, and blue * 65536.

looking back at your question, you need help in the making, and not the using... in which case my post is useless. sorry. i can't think of how you'd easily make one.

julz

yes the reason is just more precision. Ideally you would use a floating point texture, but right now I dont know of an easy way to generate them.

For instance, most topographic raster data is stored in various floating point or 32-bit formats...most DEMs are in such formats, from like the USGS and the space shuttle topography data..(this is cool stuff btw).

Also, progs like World Machine and Terragen use a floating point format to store heightmap data. There is however no easy way to convert these formats into a game usable 32-bit or 24 bit image. The best I can do is try various height gradients, such 0,0,0 -> 0,0,255 -> 0,255,255 -> 255,255,255 so that you have a full use of the color channels. However my attempts with this have not been all that improved form the 8 bit, and sometimes overly "chunky" or rounded.

Also, think about this: normal maps derived from simple 8 bit greyscale have alow precision as well.. you can make better normal maps using rgb channels..(if you want to make the normal map form a heightmap).

i c, thanks for clearing that up for me. You'd probably have to make a third party conversion tool, that will turn the pic into a hmp, and then open it in med, if med even supports that high of a precision.

All i want is a way to make 24 bit maps instead of a grey scale map.. MED supports this..

no test, and not sure to work, and I not sure to understand it

in photoshop you can use the levels(in "new fill or adjustament layer)

you need touch the output levels for create a three grey scale files, the first from 0 to 82, the next from 83/82? to 164 and the three from 164/165? to 255.

my terrain generator (see my homepage) supports that. you can import it in med... r*65536+b*256+g afaik.

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I am just wondering if anyone has any good ideas on how to make 24 bit (or 32 bit)heightmaps.. that is using the rgb channels for the heightdata instead of just a greyscale heightmap..

I have had some success using various software like World Machine, Terragen, etc.. but its diffcult to get a very smooth gradients even from here..

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That's easy, using Photoshop or any other software supporting layers where you can see the channels, just open the channels tab, select all and copy the red channel, the blue channel and the green channel into a new image. Don't copy the RGB channel, you don't need colors. Next step is arrange the layers in such a way that the darkest grayscale image is the bottom one and the lightest is on top. Now adjust the transparency of the two top layers in the way you like and you're done.

Ow before I forget, if you copy the channel layers into a new image you have to open a new document and make sure it's RGB, otherwise Photoshop automatically preselects greyscale and thus 8bit.

Well, at least this is how I do it all the time,

Cheers