MAKING OF: Blender in 2.5D Games

Материал из Blender3D.

Перейти к: навигация, поиск

Introduction At we develop a varied mix of games and animations. From 2D games using cartoon style vector graph- ics to real time 3D games and the full gamut in between. The production pipeline for our 3D games is probably no different to most 3D game development. Character design, high poly modeling, texturing, rigging, animation, effects, low poly texture bak- ing and normal maps, etc. What seems to be covered less is how you can in- clude 3D tools such as Blender in your 2D or 2.5D games and animation production pipeline. You can produce just as impressive graphical assets using Blender with your 2D or 2.5D games as you can with traditional pixel based and vector based imaging tools. With the added benefit of being able to make significant changes to your scenes and render a new result almost instantly. To illustrate this I'll outline how we have used Blender in our production pipeline for some of our Flash games. We have used Blender extensively throughout our catalog so will limit the scope to 3 projects; namely 'Matica Air Race', '6 Nations Rugby' and 'Winter Pinball'. Winter Pinball The simplest use was for the playfield background of our Winter Pinball Game. All that was needed was a 2D image of a 3D Wintry scene, trees, snow, and some stars. We could have used Photoshop, Gimp, Inkscape, Flash or Illustrator but it only took about 1 hour to create using Blender. A subdivided plane for the landscape, a simple parti- cle system for the snow, and 2 very simple sub- surfed meshes for the trees and stars took minutes to create. Then all that was left to do was to play around with the colour ramps and material nodes to get the look we were after. During the game development process we changed the layout of the pinball table and were relieved the playfield scene was created using Blender. The trees in the scene overlapped table components which had an undesired effect on the overall look. The fix was just a case of rearranging the scene a little to fit the new layout and then rendering it out again. The rest of the pinball table was modeled in detail using Blender. We needed a 3D model of a pinball table for another couple of projects so had to go through the process anyway. It would have been just as quick to hand draw the table, but having it in 3D allows us to make changes to the table and have our new image at the push of a button. The specular highlights and shadows help a lot with the 3D look but were not enough on their own. For the final render we tilted the table and used an orthographic camera. The tilt was needed to help the 3D look (showing the front edge of the table components), and we needed everything to be orthographic for the graphics to match up to the underlying game physics keeping the sides of the table parallel. Render layers allowed us to render everything below the ball and everything above the ball as separate images. This way in the final game we could have the ball passing over and under the correct table items adding to the realism. We tried using a separate shadow layer to add to the realism. It made just a subtle difference as it only ef- fected shadows on the ball which was moving so quickly you could hardly notice them. It would add to the final file size of the game so we went with just 3 layers and merged the shadows to the base layer rather than using 4 layers. Without straying from the main topic and going into great detail about how we modeled and textured each component, that pretty much covers the use of Blender the pinball game. Matica Air Race Matica Air Race was the first game we developed using Blender in our production pipeline. Therefore, it took much longer to produce the graphical assets than Pin- ball due to the learning curve. What we wanted was essentially the same as for the pinball game, 3D sprites. The difference being that we needed an animated 3D sprite for the Aeroplane. So there was no real difference apart from rendering out an animation rather than a static scene. We rendered the aeroplane doing a 360 degree roll, and rendered the propeller animation separately as we could get away with a lot fewer frames of animation for the propeller and put everything together in the game. I'd modeled the aeroplane using very roughly sketched blueprints I'd drawn by hand. I did this while watching video footage from the Red Bull Air Race, so the final aeroplane had pretty realistic proportions. This would have looked perfect in an animation but didn't sit well when it was put into the game as it was too long and thin. It's something that is difficult to get across in an article but when we played our first prototypes of the game it was very clear something wasn't right. Having the model, animation, and textures waiting for us in Blender, we could scale the model on one axis and render again to have a fully animated shorter and faster version in minutes. We quickly had a more cartoon like aeroplane which suited the movement and look of the game. We had planned for the aeroplane animation to be used as a guide to produce a vector drawing but it was so good we stuck with the rendered images. At the small size we needed for the game the raw render looked sig- nificantly better than our vector tests and there was very little overhead in terms of filesize. We went on to model other items for the game; rings, air gates, blimps, hot air balloons, even the 02 Arena all of which were very quick to create. We got a little car- ried away and modeled Tower Bridge which took an age to model and texture especially as it was our first Blender project. We could have certainly drawn that quicker using traditional 2D imaging software. Many of our games and animations are not on our web- site as we are often hired to develop a bespoke project for a particular client. The games that make it up on our website are games we developed internally for fun and we often re-brand them for Clients which helps us to recoup our costs. It's clear to see the benefits to using tools such as Blender in these cases. We can add a client's logo to the Air Race Plane, Balloon, or Blimp very quickly by chang- ing the textures or even giving the textures to the client and letting them make the changes. We can totally re- brand our games in hours rather than days. Rugby Our Rugby game has existed in some form or another for a decade and all graphics were initially hand drawn using traditional 2D imaging soft- ware. This game gets a refresh every couple of years and during our current refresh we have re- placed our hand drawn 3D assets (goal posts and a few other assets) using the same process that we have already outlined. More interestingly, one of our cli- ents wanted the game re-branded, and requested the addition of an intro to the game. They wanted a ball to fly onto the screen then go into a mode of spin- ning around, stopping, showing a message, spinning again, showing another message, etc. We estimated 125 frames of animation would be needed (around 5 seconds) adding 2 or 3Mb to the game which until now was under 120k. We had to somehow add the intro without introducing this additional overhead. The game would be promoted at events on plasma screens so had to scale up to 1920x1080 pixels. Not a problem for most of our games, as they use vector graphics, but quality would be lost if we used bitmap images at a lower resolution. We used Blender in the same way we had used it in the 'Matica Air Race' game to model, texture, and animate the ball. Blender allowed us to export the animation as a series of .png files with transparency, and at the cor- rect resolution to match the game. To achieve a result that would add just 80k instead of 2-3Mb, and that would scale to any size without degrad- ing we Rotoscoped the animation which has worked well for us on past projects. We had actually planned to Rotoscope the 'Matica Air Race' Aeroplane but the original render results looked much bet- ter than our Rotoscope tests and as I mentioned earlier the file size was pretty good any- way. The images I've included in this article are thumbnails of the final Rotoscoped vector images not the original rendered imag- es. We loaded the .png files we had rendered in Blender into Flash and traced the 125 frames by hand. We played fast and loose for most frames only spending 2 or 3 minutes per frame as it gave a good visual result without being too accurate. The last frame we tried to get close to perfect as that was the only frame that would be in view for more than 1/25th of a second. The resulting animation was just 86k and looked indis- tinguishable from the original animation when playing at full speed. I've animated 3D scenes by hand in the past with just a few reference images and my imagination, and I've used this Rotoscoping technique working with Blender animations as a template dozens of times. I'd need a very good reason not to use the latter as it saves much more time than it takes to create the Blender animation, and the result is a lot smoother. You can stray from the original animation if you change your mind and want to get creative (which we do more often than not), but it's always there as a guide to help avoid your animation getting too jumpy, to give a guide to maintain the volume of your object, and as a guide to where the shadows and specular highlights fall. It would be easy to go on describing more examples were we have used Blender in other creative ways in our projects, but hope what has been covered so far is of sufficient use to those planning similar projects. Extra Resources We have articles on our Website covering the making of a handful of our games, and have started recording game development video tutorials for our 'Game Univer- sity' section. - The Games How we make the Games Our new Games University section on how to make games Alex Aylesbury Professional game developer for 16 years, developing Web based casual games since 1996 and founder of &

Личные инструменты