Hi, let me start by answering your questions:
1) What you refer to is usually called picking and involves a bit of math. Your initial goal is to get a ray (defined by a starting point and a unit length direction) from your touch coordinates. This can be done via GLU.gluUnProject (http://developer.android.com/reference/ android/opengl/GLU.html#gluUnProject(float,%20float,%20float, %20float[],%20int,%20float[],%20int,%20int[],%20int,%20float[], %20int)). With this ray you can now check wheter an object in your world has been hit. Usually your objects will have something called a bounding volume like a sphere or an axis aligned bounding box (nice keywords for google). All you then have to implement is a ray/bounding volume intersection test which tests the ray against all your objects' bounding volumes. Among the objects that intersect with your ray the one nearest to the ray's starting position will be you touched object. Simple eh? :) 2) There's no support for any 3d formats in Android out of the box and i guess that will stay this way for good reasons. 3) That's a matter of taste i guess. I myself use OpenGL for everything. Others add standard GUI widgets on top of the GLSurfaceView. The later is a bit easier while the former is more flexible. Chose your poison. 4) That would be cool, maybe we can collaborate :) Additionally i want to link to Robert's great introductionary text on Android game programming you can find at http://www.rbgrn.net/content/54-getting-started-android-game-development. Make sure to also check out the other articles on his blog. Furthermore i'm currently writting a small and hopefully easy to use game programming library for cross plattform development myself. It's called libgdx allows you to code up your games on the desktop with standard Java emulating OpenGL ES via Jogl and seamlessly deploy them to an Android device without changing a line of code. I'm currently giving it the finishing touches, the only thing missing is the OpenGL based GUI system i rewrote from scratch as well as the Audio classes. If you want to collaborate just drop me a line, the more hands the faster the lib grows. You can find info on the lib at http://www.badlogicgames.com and http://code.google.com/p/libgdx/. Hth, Mario On 15 Mrz., 17:28, Ronnyek <wwe...@gmail.com> wrote: > Hi, I'd like to just start off by saying I've done a bit of research > into 3d development, and am confident in simple lets build some simple > 3d objects, and render them... would be easy. > > I also have a very long history writing software, understand how games > work internally etc. I understand 3d concepts, 3d space, shapes, > camera, lighting etc... but I do have a couple questions. (and no I > dont expect anyone to hold my hand through it, more than happy to put > the work in) > > 1) Initially I wont need it, but how do you handle for touch > interactions with a given 3d object on screen? I've heard of doing > things like mapping screen vertices to objects and when you touch in x > region, you are touching x object. Is there an easier way? > > 2) I intend to take a 3d format and import into my app, and there is > plenty of documentation on the formats I intend to use, so I can write > an importer... but does android 2.1 support anything out of box? > > 3) For basic menus and screen overlays, are those typically drawn with > opengl stuff too? Or a diff sort of view layed over the top of > glsurface? > > 4) I don't know if I'd say I want to build a 3d engine for android, > but I definitely think writing some useful utilities and wrappers and > converters to simplify some of the most common bits, and perhaps > document my efforts in blog, might be helpful to others. These bits > I'd like to make opensource.. any recommendations on features you'd > all like to see? (or maybe this is reinventing the wheel) > > I appreciate everyone's time, I assure you I've done some research... > and want to help prevent future newbies from running up against the > same problems I am. (trying to build wrappers and helpers and > converters etc) -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
