#so what i meant was: this software has tormented me for ALMOST half a decade

[dragonpropaganda]

Not what i was thinking i was gonna post on halloween, but this software is so fucked up it’s scary. Gotta say, the way rain world levels work is utterly fascinating to me. Like, technically and visually. It’s important to note rain world is a 2.5d game here. Let’s get an image example: GW_A24 (which stands for garbage wastes single screen room 24 in room file shorthand)

Note the 3-dimensionality of the space, as well as survivor’s shadow on the curved stone pillar behind it. This is rendered as 2.5d in the gamespace. Now let’s look at the room render in the files:

A... flat .png image? Yes. Rain world renders this 2.5d world from a red depthmap. The overbearing redness may stick out, far from the browns and toxic greens of the room in-game. This is because the game applies palettes

In the bottom left corner, see the palette menu, note the fade palette? yes, rooms get not one but two palettes to play with, which gives much more colour depth and variance in a region.

toning down the toxic fade palette, we get nothing but the sun-bleached grey palette 9, and turning it up...

Yeowch! The toxic hues in full force. Obviously this palette, palette 11 couldn’t be used like this, but with palette 9 as a moderator, it manages to show the intense pollution of the garbage wastes.

Now, as for the origin of the png image, it is created in the rain world level editor. To someone who has not used the level editor, this may seem simple. To someone who has, the mere mention may bring a tear to their eye.

the editor is split into quite a few editors, but here is the most relevant one for this, the tile editor.

One look at this and you might think “hey, those assets look like they were drawn in MS paint, where are my 2.5d objects? And where are the objects lying on the floor?” To answer this, i must elaborate. The tile editor shows previews of the tiles. the actual models, or to resort to technical vocabulary, voxelstructs, would be too impractical to render within the tile editor. The models are, too, stored as pngs, descending from the closest layer to the furthest, with the editor symbol positioned last. As an example, have the “big brick” tile that features prominently. The amount of times a layer repeates is controlled in the tile’s line in the init (ie: [#nm:"BigBrick", #sz:point(2,2), #specs:[1,1,1,1], #specs2:0, #tp:"voxelStruct", #repeatL:[1, 1, 1, 7], #bfTiles:0, #rnd:1, #ptPos:0, #tags:[]])

The RGB layers are used to generate the 3d model for the render, and the black outlines are what are shown in the tile editor.

Non-grid aligned objects, or “props” are placed in the prop editor, and they do use the 3d layers. This is because it is necessary for the prop editor’s function. While the tile editor is limited to the three major layers, the (2.5d) world is made up of 30 pixel layers (well, gameplay objects exist between layers 5 and 6, and water starts either between layer 0 and layer 1 or above layer 0) , and props can be placed as starting from any of these layers.

These are all assembled to make a 2.5d level... in red, green and blue. Not yet in the red read by the game. And also notice: there aren’t any plants! plants are generated by effects, which you can see haven’t been fully applied yet. The dark space surrounding most rooms is one, called “BlackGoo”

I don’t really have the strength of will to elaborate on effects, so onto lighting we go: the sunlight in a room is generated from an often crude monochrome image, which is projected onto the layers of the room after effects are generated, many of the intricacies of the lighting exist through light angle and distance.

In the last stage of rendering, the harsh red lightmap generated by this projection is used to determine whether a pixel is sunlit or in shadow. Light distance and angle are also saved for the game, so that it generates the shadows of gameplay objects in accordance.

All of this isn’t quite how it works but rather... an approximation. The editor still has many strange things, but this is what i’ve worked out from my own experience with it, as well as the experiences both of the modding community and others who worked on downpour. So yeah, basically rain world rooms go between 2.5d and 2d multiple times and it’s fucked up and the level editor is probably possessed by some kind of evil spirit. This piece of software is the hardest i’ve ever had to deal with, and apparently it’s even weirder internally, like half the code is in swedish. I haven’t even gotten into describing how the blues work, and i won’t, because i have no idea how the blues work, just that everything that isn’t controlled by the palette is rendered as blue.