Rpg Maker Developers Group

Disclaimer: this is not clean. this is not perfect. this won’t work all the time.
But: this is a lot better than nothing at all. this is approachable. YOU can do this, unless you are legally blind.

I realised I had written multiple smallish tutorials for requests, but no single one sorted out tutorial for the method altogether. So here we go!

How well this will work really depends on what you want to convert to which style, at the end of the day it is up to your own judgement if a result is good enough for you.

It really won’t work well on charsets and icons, some larger tileset items like trees could work depending on the used styles, but I personally would say it works best on battlers, battlebacks and faces.
Bonus points if you use the conversion on all of these so they come out uniform!

So to have a base to discuss this, let me use an example: https://themightypalm.itch.io/the-mighty-pack? by @The Mighty Palm
There is also a free addition with battlers.

So how would I tackle not having battlebacks and faces for this pack?
Sit down in a corner and cry? Of course not.

There are several things that I want to know about my pack before I even start think about a solution (the "answers" might differ for the style you are working with, I'm filling them out for the mighty pack!):

Is the style more cartoony or rather "realistic"?

Clearly, the style is more cartoony, with not much dithering or trying to emulate "inbetween" shades or softer transitions between the limited colors.

How large is a pixel?

To emulate a retro look, usually artists create their work on a smaller scale and upscale them then, resulting in a single pixel being 4 times or 9 times the original size. Usually you will have a 16x16 tile upscaled by 200% for VX/Ace and by 300% for MV/MZ, but there are some outliers, some people make 24x24 tiles and scale them up by 200% for MV/MZ.

I double checked, and the contents of the mighty pack have been upscaled by 300%. This is an important information that I will use later.

What is the color palette?
This can be tricky, since sometimes the artists don't use a fixed palette.
Some artists release their palette, but here I couldn't find it at first glance.
What I could do though, was simply plopping several of the resources on a large emtpy sheet and then use the "count colors used" function in graphicsgale:


I can then use another funtion graphicsgale offers:

Color depth allows me to limit the amout of "allowed" colors for a picture, graphicsgale will automatically choose the optimal colors for me. And if I limit them while there are less colors than the limit anyways, the resulting palette is all the colors.


And now this image is limited to all the allowed colors, for one, if I screenshot my palette and paste it in, I have a small convenient palette picture:

(you can see how the light grey border vanished, the color was not allowed and the closest in the palette was white)
I can also copy anything into this picture now and its colors will be changed to those of the palette only.

For example, if I plop the medusa battler in as-is, it will come out like this:

You can see that this alone already changes the look and feel a lot.


But let us go through the full process for a battleback for example.
This is a simple combination for a battleback from the default MZ options:

We will need:
-to make it more cartoony
-change the pixel size
-get it into the right color palette


Step 1 (optional): style adjustment

Sometimes, your conversion comes out better if you exaggerate features before the process and smooth things out. Filters like gimps cartoon filter usually look horrible, but if we look at the mighty pack, black is in fact used as the darkest color and we work with a very limited range. So this step can help your outcome, especially if you are after a cartoony look anyways.

So after a first adjustment, this is my result:


Step 2: the pixel size
The math is pretty simple: one pixel needs to be 300%. Our image is already the right size, so to get those "bigger pixels", I need to scale it down first and then scale it back up again. So...






And just like that, we got the pixel size right!

Now all we have to do is..

Step 3: the palette
We can now copy the image over to our indexed image to convert it - as we already established, copying anything over to an already indexed image with the desired palette will convert the image. This would be the result:


Here is a good chance to stop, test and evaluate if this is the desired result.

It isn't bad per se, but I personally feel like there are still too many colors and too little black in my background to really go with the style.

So, back to the drawing board:

This time I go a lot bolder with my filter, since I WANT less detail and color range:


After scaling the look is already closer to what I want:


But my full conversion still is not as I like:


There are still too many colors for what I want here. So, I go back to the downscaled image...


and limit the colors already before conversion:


There is no right or wrong amount, a lot of this will come down to what you think works as you like it to be.


The result of this conversion will look like this, upscaled and in the right colors:


And this is how my test looks like now:


But what if... the pack is high in contrast and saturation, maybe the battleback would look better if I did something in this department?
I can always try around with all the recoloring options for different looks and feels and see how they impact the result:








The bottom line here is, you will have to play around to find your perfect conversion system - but once you nailed it, you can use it on every other item of the same default style you want to convert!


So, here the process I worked out in this tutorial for a MZ to Mighty Pack battleback conversion step by step on a new battleback!



Step1: Cartoonify

Since the style is not realistic at all and uses the heavy black, this is a shortcut to eliminate details, deepen the dark shades and bringing the colors closer together. In this case, the percent black is something I'd adjust for each image, here there were too many dark spots in the foreground that I didn't like with a higher value.



Step2: Scale down

Simple as that, the interpolation none is important, other than that, you turn the 1000px width into a 333px one.




Step3: Limit the colors

For this particular conversion, I find it easier to limit the palette even further before I really port the colors. The amount of colors really depends on how many your original picture had and how much you want to preserve. I went with 12 here, just try and see what works. You can always try again with another number



Step4: Upscale again

Interpolation none and back to 1000px width.



Step5: Color adjustment

Make sure to set your image back to non-indexed before you adjust the colors.
While I am more down for muted colors, the Mighty Pack uses bold colors and I would want to reflect that a little more in the battlebacks than they'd turn out otherwise. Usually, a bit playing around with the color curve does the trick:




Step6: Copy into a picture with the right palette to enfore the palette

Usually, this will now look as you like. If not, adjust the colors before copy it in and out until you like the result.
There are other ways to enfore a fixed palette, I just usually use this one.


And there we are!

Indexing colors can be a bit tricky, so e.g. after pasting an image into an indexed file in graphicsgale, you need to paste it into a non-indexed one first before you can paste it into Gimp again, otherwise it doesn't come out right.

I would always recommend converting a whole battleback so you get the desired overall look.

This also can work for facesets and battlers, just within the range it can work. Don't expect magic, but don't write it off either.


Since you usually start this process by scaling down the battleback, you could also use VX/Ace and XP styled battlebacks as a base for the conversion, just scale them down by 50% instead of 33% and then up by 300% as you'd do with the MV/MZ ones.
Here is for example a quick and dirty conversion of the XP ice cave:



It would also allow for using VX/Ace sized faces as a base for retro faces in MV/MZ. Maybe something for another day?