Antiryad GX Engine Interview

Antiryad GX Engine - Exclusive Interview

This week, we'll be focusing on the Antiryad GX by Arkham Development. What is it, you ask? The Antiryad GX is a game engine which features supportive middleware functions such as full 3D capabilities--including bump-mapping--an embedded BASIC language and much more. The Antiryad GX also has major support for multiple consoles and operating platforms, including PC, Mac, PS2, PSP, Xbox and Linux, to name a few. Here's some questions we tossed at Arkham Development's Antoine Guillon regarding the Antiryad GX.

XboxCore: We know that Antiryad supports multiple platforms for development, including the Xbox. As of now, you're not a registered engine developer for the Microsoft Xbox, but would you consider becoming a registered developer?

Antoine : We're actually searching for solutions to register Arkham Development as a company. Until the company is created, we cannot be an official Xbox registered developer.

This is why the Xbox version of the engine isn't available for download on our website. If some customers need an Xbox version of our engine, we will be ready to register to the Xbox developer program. Antiryad Gx was developed for the Xbox with the knowledge of our developer who worked previously in another registered Xbox game development company.

XboxCore: Are you registered with Sony to have your engine used in developing titles for the PS2?

Antoine : This is exactly the same situation for the Xbox platform. Recently, though, we ported the engine to the PSP using the free homebrew PSPDev compiler and libraries (http://pspdev.org/).

XboxCore: How much more difficult is it to program an engine to support the current generation consoles, as opposed to PC-only software environments?

Antoine : Consoles are often more limited than PC. To create a multi-platform application, the software API must be created with knowledge of these limitations and differences. It's not very difficult to create cross platform applications, but the architecture must be very clean. Some important parts, when programming, must be done very carefully:

- The core of the engine is written in C language. This language is the most portable programming language. C++ can also be used, but more carefully because of the complexity of the syntax that makes the compilers different.

- We limit the use of 'standard' C/C++ system libraries because they cannot be fully supported on some platforms; we have rewritten our own system libraries.

- We compile the source code on several compilers (Visual Studio, Gcc, Watcom...) and several operating system (Windows, Linux, MacOsX, DOS).

- Specific optimized routines in assembly language must be limited and also must be written in C language.

- We support several 3d rendering API (Software rendering, 3dfx Glide, OpenGl and DirectX 5,8 and 9).


- Platform dependant functions are written in localized modules (driver modules) separated from the core engine (file access, memory, thread management, 2d and 3d display...).

- The file management must be done carefully for the big/little endian order of the different processor families.

- Also, the size of the graphic assets is an important issue when creating a game because of the memory limit, the number of triangles, animations, size of the textures; the complexity of the shaders must be limited depending on the platform used.

XboxCore: How long has the Antiryad 3D engine been in development?

Antoine : Some system libraries present in the engine was written in 1993, but the Antiryad Gx core has begun in 1997. It's constantly in development, and a new 1.5 version is planned to be available in one month.

XboxCore: The engine features transparent environment and gouraud bump mapping shading. Running on your engine, this looks exceptionally nice. Feel free to correct me here--but a brief explanation of this feature for those who don't know is that: This is a mixed transparent effect that gives textured objects detailed ripples or notches with gouraud shading. Is this Antiryad feature, fully compatible with the PS2 and Xbox hardware?

Antoine : Shaders can be customized directly by the artists when modeling. Several layer per triangles can be done (multimapping), using different transparency effects (alpha, additive, substractive, multiplicative blending). The transparent effect is used for glass, particles and reflection effects. The gouraud shading effect is used for lightning. Three main methods exist for creating bump mapping: emboss, bump mapping, environment bump mapping and dot product bump
mapping. We tried the three solutions, and finally we used the emboss bump technique because it is compatible with all hardware. The most limited platform, though, is the PS2, but 95% of the shaders work correctly.

In some case, the rendering can be a bit different on the PS2 platform because of the difficulties to render multiplicative transparency with the Graphic Synthetizer. But the multiplicative blending (often used for the lightmap effect) is not very important and can be replaced easily by substractive blending.

XboxCore: During a diagram of the engine's functionality, we see that vertices on models will be wielded during the animation process. For those who aren't familiar with vertex animation, this can be quite difficult to work with if there are too many vertices jumbled together. Is the wielding feature used to help objects such as characters, vehicles or animals animate with less vertex cluttering?

Antoine : This technique is effectively used to correct hole problems in the mesh when using animations. It is generally named deformable faces, skin / bones methods or the armature effect.

Characters consist of several rigid objects, and some vertices must be shared and blended between different animated objects. The more difficult issue does not come from the number of shared vertex, but comes from designing a realtime mesh structure with shared vertices that have the less visual deformation as possible when animating the character. Another more flexible method to animate a
character is the morph system, but it's not used frequently because this method needs more memory; the animation is not attached to objects but to the vertices.

XboxCore: Fogs, mist, and other visual effects makeup a large part of the gaming world these days. What sort of fog effects can developers manipulate using the Antiryad Gx engine?

Antoine : Many special effect are available in Antiryad Gx. Effectively, there are standard and localized volumetric fog, but also dynamic water effect, 3d sound emitters, and particle systems exist to add specific ambiances in the environments. The particle system can also be used for creating spectacular effects like volumetric fog, explosions, fire, wind, smoke, fluids...

XboxCore: What genre of gaming does the Antiryad engine caters toward? From the documentation, it seems like first-person shooters are favored?

Antoine : Some samples and specific script modules are available in the SDK to quickly create FPS games, but all type of applications can be made with Antiryad Gx because it is a generic 3d game engine. It has been used to create adventures games, and can also be used for car simulation or platform games. It is a full platform development environment designed to help to create any cross platform multimedia application.

XboxCore: Will the engine possibly have implemented support for the Xbox 360, Nintendo Wii or Playstation 3?

Antoine : Yes off course. We have ported the engine on MacOsX (PPC) especially for future development of the next generation consoles. All these new machines use a little endian PPC processor like the Macintosh PPC architecture. It is easier to port the engine to these new platforms than older, limited consoles. The implementation can take anywhere from 5 to 20 day of work.

Our thanks go out to the Arkham Development team for providing insight into the Antiryad Gx game engine. If you're interested in this product, you can check out Arkham's mainpage at: http://www.arkham-development.com. Be sure to stay tuned in with Xboxcore.com, as next week we'll be bringing you IDV's Speed Tree.

Article By: VGcore Staff