Catálogo de publicaciones - libros

In this introductory chapter, we have surveyed the major hardware and software features of mobile and handheld devices. Different kinds of hardware, such as handhelds, smart phones and mobile phones, have been discussed. The three major operating systems have been presented in order to have a clear idea of the platform strengths and limitations on top of which we will build our mobile 3D graphics applications. We discussed standard graphics software packages and presented a model for the coordinate system pipeline. Graphics programming packages require coordinate specifications to be given in a Cartesian reference frame. We discussed the many different changes in the coordinate systems from the model to the rendering of the final 3D scene. We explained that functions available in graphics programming packages can be divided into graphics output primitives, attributes, geometric and modeling transformations, viewing transformations, input functions, and control operations. Concerning software packages, we described the OpenGL library consisting of a device-independent set of routines for managing 3D graphics. We then focused on mobile 3D graphics presenting the main issues, both from the performance and the appearance points of view, considering the limitations of handheld devices. We described the main software packages that will be presented in this book, the OpenGL-ES and JSR-184 specifications. These packages work well together, providing both low- and high-level access to mobile graphics features. We will explore how to obtain graphics results on mobile devices as good as those on workstations.

This chapter presented what we believe are the more challenging and interesting scenarios in applications of three-dimensional mobile device graphics. We have identified three main areas of application, that many researchers, both in academia and in industry, are studying: mobile tourist guides, augmented reality, and mobile gaming. All these fields are challenging, and many steps are needed to evolve applications for better usability levels. The graphics technique and libraries we will describe in this book are, or will be, employed in the mentioned areas. Usability is a main issue for mobile devices, and with the increase in multimedia applications it becomes a very important topic. We explored usability among current devices, both describing the unresolved questions and the existent solutions. We then focused on new algorithms and architectural scenarios generated by new mobile device graphics capabilities. We presented recent results on architectural and algorithmic solutions for the three-dimensional scene rendering on mobile devices. These techniques are an initial step toward rethinking and optimizing programming code for the constraints of mobile devices. These architectures and algorithms highlight new problems in computer graphics that are stimulating the scientific and industrial community.

In this chapter we explored the OpenGL ES library, describing the rendering pipeline associated with it. We then introduced many of computer graphics’ basic concepts, such as: windows and mouse interaction and geometric primitives. We described all the concepts involved in the rendering pipeline by giving examples with OpenGL ES API. We provided snippets of code for geometric primitives and per-vertex operations, lighting managing, per-pixel operations and texture mapping, and finally per-fragment operations. We defined concepts and then provided sketch code for their implementation within the OpenGL ES library; for complete working code examples, refer to Appendix A. We concluded our OpenGL ES description by describing future developments, like , which are a powerful extension to OpenGL ES API. We provided also a pseudo-code for the shaders in order to show users their abilities to change the rendering pipeline, thus revealing a powerful tool for optimization.

This chapter introduced M3G and the Java Mobile 3D Graphics library, and described how an application could be developed for mobile devices supporting this standard.

We described also the frameworks (CLDC/MIDP) used by Java for managing mobile devices and applications. M3G is consider an extension of these libraries and thus it is included in their development process.We also discussed the modalities of M3G, and mode, explaining when and how to choose between the two. We then described elements of the M3G scene graph, which is a hierarchical structure used by this library for representing and managing a 3D scene.

We finally provided a comprehensive example, called , including all the concepts, elements, and API that clarify the functionalities.

Direct3D®Mobile (D3DM) is a Microsoft™-developed API that provides 3D support for mobile devices based on Microsoft Windows®OS. It is derived directly from DirectX®API already included in the desktop versions of MS Windows; moreover, it is optimized to match mobile devices’ requirements. The main source of information concerning D3DM is the library (MSDN) [45]. This chapter discusses D3DM libraries and describes the architecture of these API; we consider that D3DM API, compared to OpenGL ES and M3G, suffer from their portability; as it can be used only with MS Windows OS.

In this introductory chapter, we have surveyed the major hardware and software features of mobile and handheld devices. Different kinds of hardware, such as handhelds, smart phones and mobile phones, have been discussed. The three major operating systems have been presented in order to have a clear idea of the platform strengths and limitations on top of which we will build our mobile 3D graphics applications. We discussed standard graphics software packages and presented a model for the coordinate system pipeline. Graphics programming packages require coordinate specifications to be given in a Cartesian reference frame. We discussed the many different changes in the coordinate systems from the model to the rendering of the final 3D scene. We explained that functions available in graphics programming packages can be divided into graphics output primitives, attributes, geometric and modeling transformations, viewing transformations, input functions, and control operations. Concerning software packages, we described the OpenGL library consisting of a device-independent set of routines for managing 3D graphics. We then focused on mobile 3D graphics presenting the main issues, both from the performance and the appearance points of view, considering the limitations of handheld devices. We described the main software packages that will be presented in this book, the OpenGL-ES and JSR-184 specifications. These packages work well together, providing both low- and high-level access to mobile graphics features. We will explore how to obtain graphics results on mobile devices as good as those on workstations.