The first thing I'll need to get started is a background for one of the rooms. Without this I can't test anything else, so it's a natural first step. For this project I'm going to be using graphics I did some time ago. Here's the first scene I'm going to be using:
The space down the bottom of the image is where the interface is going to go - all of the scenes will have this gap. This takes the playable screen resolution from 320x200 to 320x144 - a common size in adventure games from the early 90s. The issue with this image, though, is that it's not going to work with the game, which has a colour depth of 256 colours. This image has thousands of colours, and so I need to take it from a standard PNG to being a PCX with an indexed palette.
When starting a new image in Aseprite, there is a choice of RGB colour, grayscale or indexed colour. Indexed colour suits this project, so picking that and specifying a canvas size of 320x200 will set the image up so that I can paste the old image in to convert it to the colour depth needed. The palette is still a standard palette, though, so anything pasted in now will use that default set of colours and become quite skewed:
To fix this, I need to specify the image's palette before it gets loaded in. I go to the palette options, select 'load palette', and select the original PNG image that I'm going to be pasting in. This tells Aseprite which colours I'm going to be using, and it selects a limited palette from the thousands of hues in the image I loaded. Now with my palette in place, I paste in the original image:
That's more like it! You can see that some banding and quality reduction has occurred, but for the most part the image remains quite intact. I can now save it as a .PCX file and import it into the AGS room editor:
Now that the palette has been set, I can paste all of my backgrounds in (because they're all painted with a very similar palette. If you have very different scenes in terms of colours used, you'd want to load a new palette each time). With that done, I can import them into the project and move on to the next step.