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Frenzy123

OpenGL C and GLUT

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Frenzy123    122
Hi, im in my final year of university(studying games programming) and for one of my projects i am trying to create a simple particle engine on the PS3 using GLUT to test performance with and without the SPE. My problem i have is C and GLUT related and it is probably worth mentioning that both were new to me a month or so back, although i have used OpenGL before(GL/GLU). I have a simple particle struct with variables for position and velocity etc, a particle system struct which holds a number of particles and finally main which calls the relative GLUT functions to setup a scene. I also have several functions which allow me to set the particles variables, update the particles and also render. Each of these functions takes a particle system pointer as a parameter. My problem is with the callback function, i have the usual display function which i want to render and update my particles but at the same time i dont want my initialisation in this function i need it in main. If i create the particle system in Main my display function isnt able to access it(which the render and update functions will need as a parameter) and if i create it in the display function then every time the callback is called a new particle system is created. Im new to C so there maybe be a very simple solution i have not thought of, i was thinking along the lines of making particle system static, but i will eventually need more than 1 particle system at a time. Any help is appreciated. Thx

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V-man    813
Yes, make your particle thing global, declare it at the top of your main.c file.
If you need more than 1, then just create more than 1.

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