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vector
09-10-2013, 02:42 AM
Hi

Is it possible to get a clipmap with soft edges? I have a blurred b/w image I want it keep those soft edges when clipping the object and I canīt get it.

DogBoy
09-10-2013, 03:31 AM
No.


There is one important distinction between a Clip Map and normal
texturing options: there is no partial clip. The information in the Clip Map
either cuts the relevant area away or leaves it intact.

If an image is used as a Clip Map, any value of 50% luminance (brightness)
or higher will clip the corresponding part of the object, while a value below
50% will not.

So it is either clipped or not. Maybe you could use a mix or transparency and clipping?

Areyos Alektor
09-17-2013, 01:52 PM
Yes a mix should work if the Clip Map is slightly smaller than the Transparency Map.

vector
09-17-2013, 09:59 PM
Thanks. The problem is I'm using shadermeister and it doesn't work correctly with the transparency texture for AOcc. It needs clip maps :(

lertola2
09-19-2013, 06:46 AM
You can bring your clip map into Photoshop and convert it to a bitmap using the the Diffusion Dither option. Then convert it back to gray scale. This will give you a clip map the simulates a transparency map. When creating the bitmap you can increase the number of pixels to the point that they will be to small to be seen in the render. This is a great way to make surfaces invisible without having to set up complex surfacing layers to hide reflection and specularity in transparent areas.

Chrusion
09-21-2013, 06:33 AM
Cool. So you're basically "half-toning" the edges of the b/w image to create a variable-density speckled pattern of b/w pixels.

lertola2
09-21-2013, 09:02 PM
Cool. So you're basically "half-toning" the edges of the b/w image to create a variable-density speckled pattern of b/w pixels.

Yes and there is an option in Photoshop's bitmap command to use a halftone pattern. But I like the randomness of the diffusion dither pattern.

jeric_synergy
09-22-2013, 09:00 AM
You can bring your clip map into Photoshop and convert it to a bitmap using the the Diffusion Dither option. Then convert it back to gray scale. This will give you a clip map the simulates a transparency map. When creating the bitmap you can increase the number of pixels to the point that they will be to small to be seen in the render. This is a great way to make surfaces invisible without having to set up complex surfacing layers to hide reflection and specularity in transparent areas.
Cleverrrrrr....

Is it even necessary to convert it back to grey scale? After all, clip maps are binary.

spherical
09-22-2013, 02:47 PM
Without testing, I'm not certain if it will make any difference in the render. That said, there isn't any point in carrying the color data, when it isn't needed. Saves memory, if nothing else.

jeric_synergy
09-22-2013, 03:33 PM
Unless they've changed it, images are always expanded anyway, sadly.

JonW
09-22-2013, 05:39 PM
Images in general try to use PNG, and grey where you don't need colour. As said above it saves memory.

jeric_synergy
09-22-2013, 06:50 PM
My bad: 2.9M vs 0.9M in my test gradient. So, grayscale will save RAM.

Some 3D software, sometime, used to expand everything up to 24bit once loaded. Aggravating.

BeeVee
09-24-2013, 06:52 AM
LightWave automatically converts 8-bit greyscale images to 8-bit greyscale images. However, if you save a greyscale JPG that will become a 24-bit image in LightWave, since JPG doesn't have a thing that says "I'm greyscale!". PNG, on the other hand, does so a greyscale PNG will stay 8-bit in LightWave (plus you can go to 16-bit per channel in PNG, which you can't in JPG and LightWave converts those to floating point).

B

dwburman
09-24-2013, 08:20 AM
Why grayscale and not a 2 color index (bitmap) image?

Lightwolf
09-24-2013, 09:13 AM
Why grayscale and not a 2 color index (bitmap) image?
Greyscale actually makes a different at the edges of clipmaps once AA is taken into account.

For a simple test, create a, say, circle in a painting application (with AAed edges) and apply that once as a 1-bit image and once as grayscale to a polygon. Then get close to the edge of the clipmap to compare renders.

Cheers,
Mike

jeric_synergy
09-24-2013, 09:45 AM
However, if you save a greyscale JPG that will become a 24-bit image in LightWave, since JPG doesn't have a thing that says "I'm greyscale!". PNG, on the other hand, does so a greyscale PNG will stay 8-bit in LightWave (plus you can go to 16-bit per channel in PNG, which you can't in JPG and LightWave converts those to floating point).
B
Takeaway="Save in PNG to save RAM."