When comparing Impact vs GameApi, the Slant community recommends Impact for most people. In the question“What are the best 3D game engines?” Impact is ranked 43rd while GameApi is ranked 58th. The most important reason people chose Impact is:
Impact provides 2 types of [collision detection](http://impactjs.com/documentation/collision); static and dynamic collisions. Both of which are easily integrated into game development.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Excellent collision detection system
Impact provides 2 types of collision detection; static and dynamic collisions. Both of which are easily integrated into game development.
Pro Extendable
Many plugins are available, including one called Impact++ which adds features like pathfinding and dynamic lighting.
Pro Level editor
Built-in map editor with support for tiling, collision layers, and actors.
Pro Extensive documentation available to support development
ImpactJS has an active user community that busily produces tremendous resources including videos, books, tutorials, walkthroughs and more. There are also comprehensive class documentation available.
Pro Truly cross-platform allowing developers to build for anything
Extending the reach of a game developed with ImpactJS is easy due to the cross-platform nature the framework. There are Considerations around performance, resolution and audio, however all can be appropriately addressed when in development. Works in the browser via Canvas, even on mobile. Easily translatable into a packaged app.
Pro All combinations of the features are working
In order to enable creation of 100 different kind of games, GameApi features are fully supporting all combinations of the existing features. This allows for huge amount of flexibility. The API carefully documents all dependencies between independent plugin-like modules and allows for combining their features in c++ code.
Pro Selection of 2d and 3d algorithms and techniques that construct opengl vertex arrays
The library is based on constructing opengl vertex arrays for 2d and 3d features including changing mesh colours, attaching textures, building larger worlds from smaller meshes, selection of predefined meshes like spheres, cubes and cones, Model loading from .obj files. Font support, gradient and other 2d bitmap operations, creation of 3d objects from bitmaps, Manipulation of points, lines, faces.
Cons
Con Not being maintained
Impact is not being maintained anymore. Last release is from 2014.
Con In alpha
GameApi has just recently moved from pre-alpha to alpha status.