evenstargw Posted July 5, 2011 Share Posted July 5, 2011 I was trying to make some black retextures of armors. I can make the textures in gimp, no problem. However, as soon as I save them and then check out the result, the dark areas will have horrible purple squares in them. Apart from not compressing them, what can I do to prevent this from happening? I've tried patching the squares by hand, but upon saving, they seem to come back with a vengeance, having brought their friends as well, making matters only worse. I'm using gimp with DDS plugin btw. Maybe another tool will get better results? Link to comment Share on other sites More sharing options...
Ghogiel Posted July 5, 2011 Share Posted July 5, 2011 pics would be helpful. Both of the texture itself, compressed and saved as what ever it is you are using, then reopened that so we can see the resultant map. And of the issue itself how it manifests in game. Link to comment Share on other sites More sharing options...
KDStudios Posted July 5, 2011 Share Posted July 5, 2011 I have experienced this issue myself in the past.I figured that editing a texture and saving it as a xcf(gimp) or psd(?)(photoshop) instead of dds prevents that from happening.Only save as dds when you're finished with the texture.Don't keep saving over it. Link to comment Share on other sites More sharing options...
evenstargw Posted July 5, 2011 Author Share Posted July 5, 2011 (edited) I have been saving the xcf files, but the problem only shows up as soon as I save it as DDS. It looks like 4x4 blocks of pixels of a dark purple color that is lighter than the perfectly dark grey surrounding blocks. I understand this is due to the DDS compression, I just don't know how to prevent it because it happens again if I try to patch it after reopening the DDS, and sometimes gets even worse. I can try to post some pictures later. Edit - I think I may have found a solution... don't use gimp to save dds files. I just tried copying the finished image to Paint Shop Pro and exporting it from there using the nvidia plugin, the result was much better. It still has artifacts as expected, but they aren't as conspicuous. It also took a lot longer to save so I think the gimp plugin is cutting some corners. This however begs the question, is there a better alternative still? Which DXT compression tool gets the best results? Any recommendations? Edited July 5, 2011 by evenstargw Link to comment Share on other sites More sharing options...
Grumpf_be Posted July 12, 2011 Share Posted July 12, 2011 I don't know if it's related but when trying to recolor a texture, the photoshop "match color" function as yet to be matched (pun intended).I, for example, tried to recolor Lava in blue and with Gimp using hue & saturation or color shifting and the result is horrible... With old 'shop, you open your texture and then create a simple gradient black-blue use the "match color" and boom, no horrible purple hue or things like that... If you're really bored: http://www.imageconverterplus.com/help-center/about-icp/supported-formats/dds/ and tons and tons of links just google. By default I personally use DXT5 from gimp, with mipmaps. (can't see from here but from top to bottom its not the last one DXT5, the one just above). Link to comment Share on other sites More sharing options...
evenstargw Posted September 27, 2011 Author Share Posted September 27, 2011 Sorry for a slight case of necro-ing, but I just found a useful article related to this subject. In case anyone has similar problems. http://www.gamasutra.com/view/feature/2467/making_quality_game_textures.php It has a lot of info about DXT and reducing artifacts, useful for anyone who has had their hard work gone down the drain due to horrible compression artifacts. Recommended reading material for anyone who wants to try their hand at retexturing stuff. Link to comment Share on other sites More sharing options...
ziitch Posted September 27, 2011 Share Posted September 27, 2011 Great find. Sadly though, it doesn't get into detail about tangent normal maps, which can have some really bad compression artifacts. Link to comment Share on other sites More sharing options...
JDFan Posted September 27, 2011 Share Posted September 27, 2011 Sorry for a slight case of necro-ing, but I just found a useful article related to this subject. In case anyone has similar problems. http://www.gamasutra.com/view/feature/2467/making_quality_game_textures.php It has a lot of info about DXT and reducing artifacts, useful for anyone who has had their hard work gone down the drain due to horrible compression artifacts. Recommended reading material for anyone who wants to try their hand at retexturing stuff. Didn't see the thread until today -- One thing I have seen that does this is if the texture is saved with the alpha channel it will sometimes get a lot of artifacts in the alpha that causes the purple blotches on your texture in game (since the game uses the .dds alpha for specular lighting and GIMP) so check that the alpha map of the .dds is correct ( Or save the texture in DXT1 with out an alpha if it is not needed.) Link to comment Share on other sites More sharing options...
Ghogiel Posted September 27, 2011 Share Posted September 27, 2011 Great find. Sadly though, it doesn't get into detail about tangent normal maps, which can have some really bad compression artifacts.Yep, none of that will help with tangent normal map compression. Actually nothing will really help. At the end of the day even shaders just storing the X and Y components to the map like in DXT5nm or swizzled normal maps still look kinda like ass. 3DC/BC5 are where it is at for compressed tangent normal maps. I jizzed my pants when I used them in Crysis :tongue: . when I played the demo I was really shocked at the normal map artefacts in skyrim, some big chunks on the lips and noses of the characters faces... :( Link to comment Share on other sites More sharing options...
ziitch Posted September 28, 2011 Share Posted September 28, 2011 There's also uncompressed RGBA8 if you don't mind the filesize. Link to comment Share on other sites More sharing options...
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