30/12/20 - Getting keyboard and mouse user input

[jakelacey2012]

In this post we'll get the users input and modify some internal state to render something to the screen.

2020-12-30.15-14-02.mp4

GLFW has some handy methods for us to do this with glfwSetKeyCallback and glfwSetCursorPosCallback the only gotcha is that the functions passed in C++ needed to be static, which meant access to the game state would be freely available. To have access to this we would have to tell GLFW "hey this is our game state, can you keep track of it please." by using glfwSetWindowUserPointer and then asking for access back to it using glfwGetWindowUserPointer to have access to the game state.

You can view the PR here https://github.com/jakelacey2012/HelloWorld/pull/7/files at the moment all it does at the moment is track the letter "E" and the cords of the mouse position. When the letter "E" is being pressed it displays a triangle.

I have some ideas of how better I'd like to pipe the events through to the game state, however what I'd like to do next is actually build a game and see how those ideas still fit whether those ideas are actually necessary. With that said I think its time to build a game, and I think that first game will be PONG.