Antialiasing problem

[Seelenquell]

hi there,

i have rendered several models with a higher resolution than needed. now i want to import them in the game. i scale them down to the right size. then i convert them using the loco-palette. after using locotool to convert them into one single DAT, i load them in the game.
i experience small white gaps/pixel where there should no one be there. after decoding the DAT i see that (i am almost sure) the locotool somehow converted the palette again.. or is ist the game?
i compared PNGs before encoding in DAT and after decoding from DAT. they were NOT the same?!

now the main-problem..
when i use pixel-doubling for downsampling there is no antialias. but what can i use to sample them down but keep the outlines sharper? now i use the bicubic downsampling. i think the problem with the white pixels is a problem with the antialias. but i dont know how to overcome this. i want a antialiased train with sharp edges. what i get is a train, antialiased, with white pixels.

am i alone with this experience? is there a solution? thank you for your answers.

gotta compare PNGs from DATs some more. before and after en-/decoding..

[BobDendry]

I wasn't aware that sprites used anti-aliasing

[Seelenquell]

I wasn't aware that sprites used anti-aliasing

to create sprites i use 3d-models with 3d-software. so to create those rendered sprites, the software uses antialiasing for the models to look good. without AA there would be artifacts, a line wouldnt be a line and so on.

i can put off AA and there wouldnt be white pixels at all.. but that doesnt look good.

sry for my bad english.. dont know how to describe this.

[norfolksouthern37]

most of the time this is overlooked, but i did come up with a way to do it. my previous released models did not use antialiasing when rendered and got A LOT of artifacts in them as a result, but at the time i did not have a better way to do it, then i got an idea. first i render a complete set of sprites without antialiasing and use the mask area of those on top of another group of sprites that i rendered with aa. this way the outlines are always crisp, but the non masked areas are antialiased. in short, render one set for the transparent color, and another set for the actual graphic, then merge them. i have the entire process scripted in my graphics editing program so i dont have to cut the mask and paste it onto the new graphic by hand, but the end result is well worth it.

[Seelenquell]

thank you..

that´s what i not wanted to do. but if there are no other solutions i´m going to try it.

[Sybil Goose]

Could you attach a .zip of an image at each stage in the conversion process? By looking at the files I might be able to see what's happening.

[Seelenquell]

here are two images..

one before and one after the locotool-conversion.

see the outlines in the after-image? these aren´t visible in the before pic and should be an antialias-problem i think

[Sybil Goose]

The first image doesn't have the correct pallette, the second does but only the colour table has been changed, which is why the colours look odd.

Have you got some images from after you've resized (with and without anti-aliasing) but before you apply the Loco pallette?

[Seelenquell]

The first image doesn't have the correct pallette, the second does

i think this is the problem.. i used the wrong palette. dont know where i got that from.. but with the "right" palette there are no artifacts so the problem isnt there anymore and this can be closed.

thank you sybil goose for this "hint"

my old palette should be a loco-palette but in the locotool colors gonna be changed.. very confusing.

[Villem]

most of the time this is overlooked, but i did come up with a way to do it. my previous released models did not use antialiasing when rendered and got A LOT of artifacts in them as a result, but at the time i did not have a better way to do it, then i got an idea. first i render a complete set of sprites without antialiasing and use the mask area of those on top of another group of sprites that i rendered with aa. this way the outlines are always crisp, but the non masked areas are antialiased. in short, render one set for the transparent color, and another set for the actual graphic, then merge them. i have the entire process scripted in my graphics editing program so i dont have to cut the mask and paste it onto the new graphic by hand, but the end result is well worth it.

Please could you make a step by step guide? Not to mention, wich program to use?

[norfolksouthern37]

i use Paint Shop Pro 8+ for this (because i have the process scripted) but the same can be done in Photoshop.

in my rendering program i set up my model and use a grey background with anti-aliasing enabled. i choose grey becuase if i used blue then the blue would be anti-aliased and grey is more neutral and will avoid the very edge problems reported in this thread. heres an example with my GP38-2 model.

this is frame 14 of the set, with ant-aliasing (grey background), and the same without (blue background):



you will notice a big difference in the quality of the model, and thats what i was trying to do so this is what i came up with. basically after you do this step, you cut the blue 'mask' out of the second one and merge it to the anti-aliased one. this process REMOVES the aliased edges, so once you convert it to the correct palette, there are no rough looking or discolored edges on your train,a nd the overall texture looks a heck of A LOT better. here ill show you another comparison of a model not in company colors. this time a Santa Fe GP60:



and the final sprite with loco palette applied:

[Paasky]

norfolk, that is PURE GENIUS!

Would you mind to write a good, easy to follow tutorial? If not, I can do it, ofcourse praising your genius in every sentence

Now I can re-start making the Aircraft Pack I was working on