I feel that this is a Zelda Classic mechanic that isn't fully understood by many. I've done some tricks with the dark room mechanics, and done some research, and I figured I'd share what I discovered.
This is going to focus on the differences between the two methods for generating fades in Zelda Classic: Interpolated Fading and Tiered Fading. You can switch between these two types of fades by going to Quest->Rules->Animation and checking or unchecking the box next to "Interpolated Fading." Fades are used for dark rooms, and for the in and out fades when using a side warp to a DMap with a different palette. Both fade styles have advantages and disadvantages.
This is the fade style used by many custom tilesets and quests in ZC. Interpolated Fading works by taking the colors in a cset, using that as a start point, and fading either to full black or the midpoint between black and your original color. In other words, there are two different options for displaying in dark rooms: faded, and black. If you open the level palette editor with Interpolated Fading on, you should see something like this:
For anyone unfamiliar with the palette editor, the numbers on the left represent the csets in the palette that can change according to the DMap. You can edit terrain csets 2, 3 and 4 to make terrain different colors in different DMaps. Cset 9 is the level dependent sprite cset that can be used to change enemy colors based on DMap. Below cset 9, also labeled 2, is the "fade cset" we'll be looking at.
Notice that there's a range of colors from black to white there? This can actually be misleading. While these colors affect the way the fade works, there seems to be only two colors that matter: Black, and everything else. If you put full black here (0,0,0), the matching color in cset 2 will fade completely to black in a dark room. If you put any other color, the matching cset 2 color will fade to about 50% of its original color. Yellow will become darker yellow, causing the room to look dim due to the lack of light. For clarity, you may want to put only full black and full white (63, 63, 63) in those spaces to easily differentiate between full black and faded colors in dark rooms.
You can use this to define what colors remain visible in dark rooms, but keep in mind that this only works for colors on cset 2. If, for example, you want only the walls in a dark room to be visible, you can put those on cset 2, while putting the floor and objects on cset 3 or 4 so the whole room is obscured except for the walls. You could also intentionally put a few objects on cset 2 to highlight them in the darkness as some sort of clue.
Here's a quick breakdown of the advantages and disadvantages of using Interpolated Fading:
- Very easy to set up
- Extra cset spaces in the palette editor can be used for palette cycling
- No need to define specific fade colors
- Fades look incredibly smooth
- Produces a smoother-looking death sequence for Link
- Always have one faded cset and 2 full dark csets
- It will dim cset 5 as long as the "Fade CSet 5" quest rule is set
- You cannot define specific fade levels, and are limited to the 50% fade on cset 2
- You can't change from one color to another during fades
- Csets 3, 4, and 5 always fade to full black
This type of fading is used by the Classic tileset included by default in Zelda Classic. If you want to use it, ensure that the box next to Interpolated Fading is not checked in Quest->Rules->Animation. This type of fade works by defining several tiers of colors that are run through during the fade. When you enter a dark room in the original Zelda, you'll see the room dim in stages. It starts at full bright, then dims a little, a little more, and then finally settles on its dark state. The same happens in reverse when the room brightens. The color tiers it cycles through are clearly visible for a moment as the fade happens.
If you have Interpolated Fading unchecked, the level palette editor should look something like this:
Compared to the Interpolated Fading image above, you should notice a few things. The "Cycling" button has now changed to "Dark." Pressing the Dark button will automatically generate fade colors like those seen here. You should also notice that the numbers on the left side of the editor have now changed. After cset 9, the numbers 2, 3, and 4 repeat for 3 different sets. These sets are the tiers of colors used for fading. In the case of this image, all of the cset colors at the top of the list dim through 3 stages through the two middle sets before settling on the lowest set, in this case pure black, for their final dark room states. Here, every single color would dim to total black, resulting in a room where the player couldn't see anything, not even the walls.
But the final fade colors don't have to be (and probably shouldn't be entirely) black. They don't even have to be darker shades of your original colors. They could be anything. Since you have full control over the fade colors, you could make the colors change entirely. For example, you might make your bright yellow change to blue during the fade.
This also allows you to define fade colors for all 3 terrain csets in the level palette, instead of just cset 2. One way you might use this is to make 2 otherwise identical csets with different fade colors. You could, say, make a gray statue that changes color to blue or red depending on whether it's on cset 2 or 3. Or make otherwise identical objects glow in the darkness to indicate a clue, like to a maze path, or a push block. If you wanted, you could even make the room brighten instead of darken. You have full control of every fade color in every cset, and can make objects brighten or darken in any pattern you want. In this way, it's much more flexible than interpolated fading, and introduces a lot of unique puzzle opportunities.
This style also has some disadvantages, so I'll cover them here:
- You can manually set the levels colors fade to
- Csets 3 and 4 don't have to fade fully to black
- You can change to different colors during the fade
- Fade colors can be different for different csets
- More flexible for making light and darkness based puzzles
- The fade process looks much choppier and not as smooth
- Cset 5 cannot be dimmed, since its fade colors can't be defined
- Requires more work to set up
- Makes it impossible to use palette cycling
As you can see, each method has its advantages and disadvantages. Neither one is inherently better, and it really depends on which suits your situation. If you want to set up complex light and dark based puzzles, Tiered fading is probably the best choice. If you want to use palette cycling, or just love the look of the smoother fades, Interpolated is probably best. I hope this explanation helps people to understand how to make the best of dark rooms in Zelda Classic. Thanks for reading.