Falacy wrote:

Lummox JR wrote:

I don't understand the emphasis on doing lighting without shadows, because the concept makes little to no sense.

If you put a light in room, it would only light the interior of that room, being blocked by walls and such. That's the basic concept of lighting.

Agreed, but I don't think that's what Forum_account is saying. I think he's suggesting that the light should simply be everywhere and not concern itself with opaque walls because it does indeed raise too many questions.

Having that same light cast shadows of players on the ground is whats being discussed at this point, though.

I see this as inseparable from discussing whether stationary objs or even turfs should cast shadows. As you said, light within the room is blocked from spilling outside by walls, but in effect those walls are casting a shadow. By definition a shadow is simply that which is not lit. This is why I said the discussion has to include shadows, unless Forum_account is indeed arguing for a more limited concept in which it's simply blobs of light not blocked by anything.

Blocking light is still a shadow; it's just a shadow of a static vs. a dynamic object. Most rendering engines may treat them differently but that's kinda beside the point.

Now another lighting model I can think of, which again would be problematic in isometric but has potential otherwise, is that very simple forms of per-tile lighting could be used to simulate overhead-only light sources that don't spill out to the side, much like you would see in DOOM.

Lummox JR wrote:

Blocking light is still a shadow; it's just a shadow of a static vs. a dynamic object. Most rendering engines may treat them differently but that's kinda beside the point.

Not really... It could even by dynamic, that still doesn't make it any type of shaped shadow, its just a light blocking obstacle.
Really lame example: http://www.angelfire.com/hero/straygames/ByondBugs/ LightingVsShadow.png (FA just posted a good example of lighting)
The system that creates light in that area, and the one that casts a shadow of that house would be completely different, and would pretty much work on top of each other.
That example would probably look better if it was just a box instead of a house...

FA wrote:

The left shows what you'd want to see, the right shows what you'd actually see. Because walls are opaque they block light and are not illuminated.

Lighting should be applied to the opaque object, why wouldn't it be? If you turn on a light in your room the walls get lit up and all...

Forum_account wrote:

Lighting effects without shadows would be very useful.

For instance, in Gunbuddy13's Beam Demo you could use colored lights to make the ground glow blue, green, or red for the different colored beams. Similarly, when a player shoots a fireball projectile the fireball is a light source, brightening the area around it and tinting it red as it moves.

Hrm, that's an interesting concept, although for beams you'd basically want a light source that was a line instead of a point. You could use many points I suppose, but that would probably be impractical and wouldn't look that great.

Being able to specify colored ambient lighting lets you create a lot of effects. Tint the player's screen red when they take damage by increasing the red component of the ambient light. Darken/brighten the ambient lighting to create a day/night cycle.

Indeed, that would have some usefulness.

I'm still not sure how you propose to handle shadows for even simple cases. Many of the examples people have provided are drawings of how you wish the system could work, but not how it actually would work.

http://files.byondhome.com/Forumaccount/opacity-problem.png

The left shows what you'd want to see, the right shows what you'd actually see. Because walls are opaque they block light and are not illuminated.

I've been thinking of something more in between, where a 1-tile width of falloff allows for the walls to be partially illuminated and the light spilling out would also have a partial illumination effect. The question then becomes though, how to get something more like your second case when you're not actually in a position to see one of those walls from the lit side. This relates of course to the question of FOV.

If there was a good way to handle shadows I'd be more supportive, but it's so problematic that any implementation would be specific to a certain usage. It wouldn't be general purpose and very few people would make good use of it. Dynamic lighting without shadows would end up having more applications despite its limitations.

Still though, the isometric question remains unanswered.

Lummox JR wrote:

You could use many points I suppose, but that would probably be impractical and wouldn't look that great.

It's a heck of a lot better than what we're capable of now.

The question then becomes though, how to get something more like your second case when you're not actually in a position to see one of those walls from the lit side. This relates of course to the question of FOV.

The simplest thing is to say "the player can't see that light source, so just ignore that light". That's why I left the the small, triangular area of illumination at the bottom. The player can see some of the effects of the light source - and you want the player to see this - you just don't want them to see all of the effects of the light source.

In a game where players are light sources, any light you can see through the wall tells you there's a player on the other side. Shadows are costly to develop and draw and still don't fix this problem.

Still though, the isometric question remains unanswered.

Isometric is much more practical because a consistent perspective is enforced and this perspective is more conducive to simulating a 3D environment (which makes for more interesting shadows). There are ways it could be done but I'm not sure it's worth the trouble. How much trouble was it to add an isometric mode and how many people use it? If you want to add shadows to isometric maps, the questions isn't "how do you do that?" but "how much of your time do you want to waste?"

Falacy wrote:

Forum_account wrote:

The simplest thing is to say "the player can't see that light source, so just ignore that light".

Good Idea

Read the rest of that paragraph: "That's why I left the the small, triangular area of illumination at the bottom. The player can see some of the effects of the light source - and you want the player to see this - you just don't want them to see all of the effects of the light source."

Ignoring the light completely will cause problems. No matter what you do shadows will be problematic. Dynamic lighting without shadows has limitations, not problems.

D4RK3 54B3R wrote:

What the rest of us are arguing for: http://i55.tinypic.com/2mfay6a.png

Adding a light source into the scene makes the entire thing darker? lol

What you're arguing for: http://i54.tinypic.com/wtelug.png

That could already be easily done, I don't think anybody is arguing for that. Just a simplified version of the first shot.

D4RK3 54B3R wrote:

What the rest of us are arguing for: http://i55.tinypic.com/2mfay6a.png

The shading on the dense tiles appears to be done per-tile instead of per-pixel. If the light source was two tiles to the right (standing in the doorway) the wall tiles immediate above and below it would be bright, but all other parts of that wall would be dark. That would look strange.

You'd still have this problem:

http://files.byondhome.com/Forumaccount/opacity-problem.png
http://files.byondhome.com/Forumaccount/ opacity-problem-2.png

When you're on the dark side of a wall it still appears bright.

What's more is, there are very VERY few games that need dynamic lighting without shadows rather than with shadows. So few, in fact, that I can't think of a single one at the present. Can you?

I actually believe that more games would use dynamic lighting than shadows. In an anime game you don't need dynamic shadows to figure out that the sunlight casts a certain shadow - that can be pre-rendered (just like commercial games have done for years). What would look nice is when the one guy shoots a blue beam at the other that the beam casts a blue glow.

As I mentioned before:

"For instance, in Gunbuddy13's Beam Demo you could use colored lights to make the ground glow blue, green, or red for the different colored beams. Similarly, when a player shoots a fireball projectile the fireball is a light source, brightening the area around it and tinting it red as it moves.

Being able to specify colored ambient lighting lets you create a lot of effects. Tint the player's screen red when they take damage by increasing the red component of the ambient light. Darken/brighten the ambient lighting to create a day/night cycle."

If the BYOND staff had a history of implementing massive features on a whim I'd be supportive, but it's quite the opposite. Dynamic lighting has plenty of uses, it's much easier to implement, and it's much easier to use (no need for opacity maps).

Falacy wrote:

if the opaque tile blocks your view of the light source, then you don't light the tile. Though, it could look a bit wonky when walking around corners.

That gives you this: http://files.byondhome.com/Forumaccount/ opacity-problem-3.png

The blue line shows which tiles block your view of the light, so only those two tiles in the way are not illuminated. The remaining tiles don't block your view of the light.

Falacy wrote:

That entire area is blocked by opacity, unless the light was reaching into an area you could actually see, like that very bottom tile

That's why I left the bottom tile open. You want to see some effects of the light but not all of them.

You know what parts should and should not be illuminated but it would be hard for a computer to figure that out. The reason is that we're trying to simulate a 3D environment in 2D. We're using clues and knowledge of the environment that the computer doesn't have. To have the computer infer this information would be difficult and problematic. To provide the information just dumps the complexity onto the developers.