AO Texturing

07-25-12, 07:48 AM

Does anyone know how to put a specular map or just a greyscaled diffuse map into the alpha channel of the AO map? i read the tutorials on this forum , but so far i could not figure it out. i am using GIMP and paint.net.
i am having artifacts of my ao map showing up on the hull of the model, and tried to delete the ao alpha channel, but still the sub is too glossy and i want to use a real specular map. best regards jh

stanger · 07-25-12, 10:45 AM

Take a look how it is done with stock sh4 textures. There is black&white diffuse map in AO alpha channel. So, take your ships texture, make it black and white, adjust it with the "curves" option (in Photoshop), so it lt looks dirty, then copy it and paste to AO map alpha channel.
I dont know how to do it in paint.net, you cant probably, but it should be possible in gimp.

(Get Photoshop cs6 30-day trial + nvidia dds plugins and you will do it in 1 minute, that gimp is piece of ... something rotten

07-25-12, 02:58 PM

well... thanks but i could use some more detailed answers.besides, gimp is great.thanks for the effort anyway.

stanger · 07-25-12, 05:38 PM

Sorry, can't help you much with Gimp. I don't understand how it manages alpha channels. For example: in photoshop you can simply select the channel and do whatever you want to do (and we want to do some basic stuff like copy or paste), but in Gimp - it wont let me paste into alpha channel. Maybe it requires to delete existing channel and create new? And try to hide an alpha channel - you wont see RGB channels as well. (Unnecessary obstacles, just like Blender

) Another thing: it displays AO map alpha channel inverted, and I know its not inverted, because I just reworked one of O01 textures just couple of minutes ago in PS, so not sure how you should proceed in Gimp: invert or not. But anyway, you, maybe, know Gimp better, so I will write how I do it:
1) open your ships texture (don't load mip maps), make it black and white (colors > desaturate) then adjust it with curves (colors > curves), so it looks similar to this:

Try not to leave too much white or grey areas, the more detail the better it will cover AO tex, the less shininess on your sub.

2) Once done, select all, copy; open AO tex, select or create alpha channel, paste. Both textures should be of the same size.

3) Save as (or export in gimp) dds (dxt5 (bacause of alpha channel), generate mip maps).

You may also want to use xnview as image viewer, you hit ctrl+h, and can show or hide alpha channel.

07-26-12, 02:36 AM

Stanger, that`s great! some tutorial you made! ive downloaded photoshop and the plugin and will give it a try asap! the possibility to select and edit single chanels sounds great, gimp cant do that! once aain a BIG THANK YOU!

07-26-12, 05:03 AM

ok , i tried the following: 1. Black&white to the ships T01, adjusting the curves-> there is a curve-mask in the channel list below RGB and the seperate R-G-B-channels. i copy and open my O01. i select the alfa-channel in the channel list and desect the rgb. i paste the textur and the channel turns all white. i tried the same with the Tambor`s texture you used and it is also white. am i missing something?

07-25-12, 07:48 AM	#1
jhapprich Stowaway Posts: n/a Downloads: Uploads:	AO Texturing Does anyone know how to put a specular map or just a greyscaled diffuse map into the alpha channel of the AO map? i read the tutorials on this forum , but so far i could not figure it out. i am using GIMP and paint.net. i am having artifacts of my ao map showing up on the hull of the model, and tried to delete the ao alpha channel, but still the sub is too glossy and i want to use a real specular map. best regards jh Last edited by jhapprich; 07-25-12 at 08:54 AM.

07-25-12, 10:45 AM	#2
stanger Engineer Join Date: Apr 2012 Location: Poland Posts: 200 Downloads: 84 Uploads: 0	Take a look how it is done with stock sh4 textures. There is black&white diffuse map in AO alpha channel. So, take your ships texture, make it black and white, adjust it with the "curves" option (in Photoshop), so it lt looks dirty, then copy it and paste to AO map alpha channel. I dont know how to do it in paint.net, you cant probably, but it should be possible in gimp. (Get Photoshop cs6 30-day trial + nvidia dds plugins and you will do it in 1 minute, that gimp is piece of ... something rotten Last edited by stanger; 07-25-12 at 11:08 AM.

07-25-12, 02:58 PM	#3
jhapprich Stowaway Posts: n/a Downloads: Uploads:	well... thanks but i could use some more detailed answers.besides, gimp is great.thanks for the effort anyway.

07-25-12, 05:38 PM	#4
stanger Engineer Join Date: Apr 2012 Location: Poland Posts: 200 Downloads: 84 Uploads: 0	Sorry, can't help you much with Gimp. I don't understand how it manages alpha channels. For example: in photoshop you can simply select the channel and do whatever you want to do (and we want to do some basic stuff like copy or paste), but in Gimp - it wont let me paste into alpha channel. Maybe it requires to delete existing channel and create new? And try to hide an alpha channel - you wont see RGB channels as well. (Unnecessary obstacles, just like Blender ) Another thing: it displays AO map alpha channel inverted, and I know its not inverted, because I just reworked one of O01 textures just couple of minutes ago in PS, so not sure how you should proceed in Gimp: invert or not. But anyway, you, maybe, know Gimp better, so I will write how I do it: 1) open your ships texture (don't load mip maps), make it black and white (colors > desaturate) then adjust it with curves (colors > curves), so it looks similar to this: Try not to leave too much white or grey areas, the more detail the better it will cover AO tex, the less shininess on your sub. 2) Once done, select all, copy; open AO tex, select or create alpha channel, paste. Both textures should be of the same size. 3) Save as (or export in gimp) dds (dxt5 (bacause of alpha channel), generate mip maps). You may also want to use xnview as image viewer, you hit ctrl+h, and can show or hide alpha channel.

07-26-12, 02:36 AM	#5
jhapprich Stowaway Posts: n/a Downloads: Uploads:	Stanger, that`s great! some tutorial you made! ive downloaded photoshop and the plugin and will give it a try asap! the possibility to select and edit single chanels sounds great, gimp cant do that! once aain a BIG THANK YOU!

07-26-12, 05:03 AM	#6
jhapprich Stowaway Posts: n/a Downloads: Uploads:	ok , i tried the following: 1. Black&white to the ships T01, adjusting the curves-> there is a curve-mask in the channel list below RGB and the seperate R-G-B-channels. i copy and open my O01. i select the alfa-channel in the channel list and desect the rgb. i paste the textur and the channel turns all white. i tried the same with the Tambor`s texture you used and it is also white. am i missing something?