Homemade 3D rendering engine (IX)

Now we have laid out the basics for rendering. Let’s cover other topics that might be useful to understand the whole game. One problem is event handling, when user click on a particular cube face, how do I respond to that event? It turns out to be rather simple, simply register a click event handler on the triangle, and record the cube face with the triangle, and that’s it. A typical solution might need to go back to the BSP tree to search from front to back.

How about animation? In my game, animation is abstracted under the model. A model is a collection of triangle, during rendering, if an animation is needed (e.g. rotating a particular face), a different set of triangles is returned using a composite pattern. A model is a transform model of the underlying model which is a cube, which is then a composition of six triangles.

So during each rendering, the whole screen is cleared, the set of triangles are obtained from the composite model, a BSP tree is built, a back to end traversal is used to determine rendering order, the projection is used to compute 2d coordinates, and a triangle object is rendered to the screen.

This conclude the design of the whole system!