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OpenGL Quality of a sprite based game

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Hey guys. I'm almost done writing a framework for a game. Making a 2D game, I've read some material on the web and realized two options I have are making it sprite based or doing it in 2D projection in OpenGL, since I'm targeting windows, android and iOS. I've decided to go with sprites for the initial version but I'm a bit worried of the graphics quality that can be achieved with sprites. I'm sure there are nice examples of sprite games that look awesome, but there's a buzz in my mind about it. "Sure you can achieve awesome looks with sprites" you would say, but my definition of awesome might differ from yours. I picked sprites over OpenGL because of animation simplicity and actually simplicity overall. I want to start small and not get caught in something I can't get out of, since I'm doing the whole game myself. So... What should I expect from sprites regarding quality(looks)?



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A: Yes it can look good, and second, B: what exactly are you trying to make? and C: what other alternative are you thinking about? I'm asking so we can compare for your particular situation,


The quality depends, of course, on drawing skills. But also about the chosen style and consistency of the graphical content. When chosing sprites, don't expect to make photo-realistic graphics. For cartoonish graphics though, it can work out really well. In facts, making your world, characters and animations look cartoonish, is easier to achieve with sprites. Because the shapes are more curvy / organic compared with polygon objects, and you have more freedom with the animations. Not that its impossible to do with 3D, but that requires high skills.


Speaking of skills, when chosing 3D, the overall difficulty to make things look *good* is higher. So unless you have plenty of time to create a "next-gen" engine + the artists that can make the content, a 3D engine will quickly look outdated when people compare it to Crysis, Unreal, or whatever we got. This is less of a problem when going for 2D. At least... if you can pick a specific, consistent style. And since you also aim for mobile devices, you can't make too complex 3D stuff anyway.



As for the technical aspect to make things look good, consider lighting as one of the most important factors. In 3D, there are a lot of options to simulate somewhat realistic lighting. Shadowmaps, geometric shapes, normal/specular mapping, (baked) GI, and so on. With sprites, this is a bit harder to achieve because your scene is literally flat, and thus lacking information you would need for proper lighting. Although a cartoonish style may not need realistic "correct" lighting, you still may need some tricks to get it look cool instead of flat and dull.


This is probably the reason why platform games are often semi-3D. Using a mixture of 3D shapes and sprites. Don't forget you can still use OpenGL for a 2D looking game. But as said, making a 3D engine requires more work in general. So if you don't really need it...




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There are games out there that have very high definition sprites, take a look at the sprites from Skullgirls and Shank for example.




Both games use 2D sprites

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@Rick: Hey there. Well, alternatives I was considering was OpenGL and just making a 2D projection from above. It's a tower defense game. Indeed it should have a cartoonish look, not realistic.


@6B!: Those two look awesome! But as Rick said, it depends on drawing skills alot.

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A Tower Defense game. I would just make it 2D. Because you will likely reach your goal faster (= making the game), it likely runs better on mobile devices, and most important, drawing topview walking characters or towers likely looks better than using (low poly) 3D models. Just compare old RTS games (Command & Conquer, ...). I found the drawed sprite ones look better than their 3D counterparts. Because sprites can show any complex drawing, while with low-poly models, you are stuck to more simplistic shapes. Same with lighting & animations.


I don't know what you are using right now, but OpenGL can draw transparent quads (sprites) just as well. Neither are you forced to use all kinds of complex shaders or lights. In other words, with OpenGL, you can do what any 2D engine can do as well. So if you like the way how GL works, you can still decide to go for GL of course. And since GL works on those mobile devices as well, its not such a crazy choice. 

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Yeah I've worked with OpenGL ES on an iOS project at work, actually. So I would make a quad, apply sprite texture, and perhaps do post effects using shaders?


I'm using SFML at the moment. It's more of a make a game and learn than anything else. I've tried to detach all the drawing code from game code, so If i choose to change the graphics engine, I just have to write implementations for drawing classes etc.


I will probably stick with sprites, just would like to consider other options.

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