Scirra’s Construct is a free, open source development studio that allows you to create DirectX 9.x based games and application in a WYSIWYG (What You See Is What you Get) environment. It includes an event based system for defining how the game or application will behave, in a visual, human-understandable way.

Key features of Contruct include:

Scirra Construct: WYSIWYG DirectX Games and Application Creator and Editor for Windows

+ Super fast hardware-accelerated DirectX 9 graphics engine
+ Add multiple pixel shaders for advanced special effects, including lighting, HDR, distortion, lenses and more
+ Physics engine for realistic object behaviour
+ Place object on different layers for organising display, parallaxing, or whole-layer effects
+ Debugger giving you complete control over all aspects of your game for testing purposes.
+ 50+ plugins ranging from Tiled Background to database access

Download Contruct for Windows XP and Vista from here