# Question Can you explain to me in detail what quads are and how they work with 2D 20 direction sprites?

Discussion in 'General Discussion' started by LONE5mpirana, Mar 19, 2024.

1. ### LONE5mpirana

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Someone on reddit told me this but I didn't quite understand him because I'm a beginner.

"When I say sprite, I simply mean a quad with a sprite texture on it with transparency.

The quads are objects parented to the bones, not weight painted as polygons are normally, because if they were weight painted like a regular mesh you couldn't rotate them independently of the bones to make them face towards the camera."

I couldn't get him to respond back so I need someone here to explain to me what he is talking about. I'll try to explain what I want to do even though I don't fully understand what I'm saying yet. I'm trying to use "quads" to build a 3D model (atleast, I think it is 3D) and apply bones to it. Then, attach 2D sprites to the quads. This is what I want to achieve. Short combat clip | EthrA 3d adveture/rpg pixelart game (youtube.com)

Are quads planes that can be adjusted as rectangles or remain as squares? Or are they 3D cubes that can be adjusted into rectangles or remain as squares? Also, how does quads face the camera? In the video I linked, Stonelabs Studio is using 20 direction sprites. What does this mean when it comes to angles? I'm a visual learner so I'm trying to visualize how quads can represent sprites at different angles with so many directions like this (20 directions).

As you can tell, I need to better grasp what I want to do. Please explain to me like I'm a 5 year old.

2. ### neginfinity

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He is describing a billboard.
https://en.wikipedia.org/wiki/Billboard_(disambiguation)

Also look up Billboard Characters, like those used in games simialr to Disgaea, Breath of Fire, Final Fantasy Tactics, etc.

However, in your video characters seem to have 3d voxel bodies. Their heads are billboard sprites.

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3. ### LONE5mpirana

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Thank you for responding! Do you know any video tutorials on how to attach billboard sprites to a voxel 3D body?

4. ### Murgilod

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No, the entire thing is billboard sprites I'm pretty sure, stepping through it frame by frame. This is where part of the 20 directions are coming from. If you look closely, you can see that the "rotation" along the local Y axis of the torso is always pixel-by-pixel.

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5. ### LONE5mpirana

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Do you know any good workflow tutorials on dealing with billboard sprite models? I need to have a good understanding of the topic. This can let me know what software to use before Unity URP.

6. ### Murgilod

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I can say that if you have to ask these questions, you're probably not really ready for what it's going to entail. You're basically dealing with implementing an entire skeletal animation system and rotation analysis system and at that point you'd really be better off just doing full sprites and pre-made animations instead of procedural skeletal ones.

7. ### LONE5mpirana

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I know I'm not ready but I will be one way or another because I want to achieve what Stonelabs Studio is doing right now. Doing full sprites and pre-made animations doesn't cut it visually.

8. ### neginfinity

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If that's the case, this is a massive overkill. With 20 frames it is easier to just use voxels.

9. ### Murgilod

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If you think that's not going to cut it visually, why do you think emulating something you're not equipped to handle will?

10. ### LONE5mpirana

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I think you're right because I think the same thing can be achieved with a voxel body. I just gotta figure out how.

11. ### LONE5mpirana

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I don't mind struggling a lot longer to achieve what I want. Of course I'm not equipped to handle this because I don't know how. That's a given and I'm willing to put the time and effort to achieve that. This is why I ask for tutorials on this matter because why would people post tutorials other than to teach people who doesn't know. Reading beginner content and intermediate to master content is all the same to me as long as it is aligned with my goals. Please, don't shrug me off because I'm not ready. I will be because I'm willing to learn everything I envision.

Edit: the other guy posting here mentioned that it's easier to use voxel art for the body. If it visually achieves the same thing, I will choose the option.

Last edited: Mar 20, 2024
12. ### Murgilod

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There aren't tutorials for this because this is a complicated process involving loads of novel steps that don't translate well to doing anything but this. One of the hard lessons you're going to need to learn about game development is that "I want the thing" is not nearly as important as "is this at all practical or even reasonable to implement?"

13. ### LONE5mpirana

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I see. Thank you for replying. I see that you care about my wellbeing. I'll keep this mind to the very end. This is why I'm thinking about the billboard sprite head and voxel body method.

14. ### neginfinity

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The first keyword to search is "Billboard" or "billboard sprite". This will give you idea of sprite that always turns towards camera.

Then you need to take a look at Doom 1, Doom 2, Heretic and Hexen games and maybe Disgaea/ FF tactics games I mentioned. Those use sprites as standin for 3d object. Basically, the object tracks where it is turned and presents different frame based on that. Also see "Doom sprites", "Hexen sprites", etc.

When you get an upright standing billboard you're almost there, BUT. Now you'll need to modify it to tilt. Of both object and camera. At this point you might want to investigate related term that is "Impostor", which is used for the trees and supports seeing impostor from multiple angles.

Then you split the object into parts and make every one of them a sprite-based impostor.

That's the rough idea.

Frankly, I'm not sure why the guys are doing that in the video. Pixelart is used to save time. If you need to draw 20 frames per hand segment, there is no saving time. For blocky look it is easier to us voxels and not this.

Anyway, here's a game using roughly similar principle:

Basically, at some point someone was crazy enough to try making a 3d fighting game on SEGA/SNES which did not support 3d. The principle is similar to the video, except a ball looks the same from all angles, hence no point in using many sprites for it.

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15. ### LONE5mpirana

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Thank you for giving me clues! I'm really curious about the billboard head and voxel body method. I can visualize how it's gonna look like and I think it's fantastic. If I can manage it, that is.