sdl_gfx_framerate.nim

Types

FPSmanager* = object framecount*: uint32 rateticks*: cfloat baseticks*: uint32 lastticks*: uint32 rate*: uint32: Object holding the state and timing information of the framerate controller.

Consts

FPS_UPPER_LIMIT* = 200: Highest possible rate supported by framerate controller in Hz (1/s).
FPS_LOWER_LIMIT* = 1: Lowest possible rate supported by framerate controller in Hz (1/s).
FPS_DEFAULT* = 30: Default rate of framerate controller in Hz (1/s).

Procs

proc initFramerate*(manager: ptr FPSmanager) {...}{.cdecl, importc: "SDL_initFramerate", dynlib: SDL2_GFX_LIB.}

Initialize the framerate manager, set default framerate of 30Hz and reset delay interpolation.

proc setFramerate*(manager: ptr FPSmanager; rate: uint32): cint {...}{.cdecl, importc: "SDL_setFramerate", dynlib: SDL2_GFX_LIB.}

Set the framerate in Hz.

Sets a new framerate for the manager and reset delay interpolation. Rate values must be between FPS_LOWER_LIMIT and FPS_UPPER_LIMIT inclusive to be accepted.

Return 0 or value for sucess and -1 for error.

proc getFramerate*(manager: ptr FPSmanager): cint {...}{.cdecl, importc: "SDL_getFramerate", dynlib: SDL2_GFX_LIB.}

Return the current target framerate in Hz or -1 on error.

proc getFramecount*(manager: ptr FPSmanager): cint {...}{.cdecl, importc: "SDL_getFramecount", dynlib: SDL2_GFX_LIB.}

Get the current framecount from the framerate manager. A frame is counted each time framerateDelay() is called.

Return current frame count or -1 on error.

proc framerateDelay*(manager: ptr FPSmanager): uint32 {...}{.cdecl, importc: "SDL_framerateDelay", dynlib: SDL2_GFX_LIB.}

Generate a delay to accomodate currently set framerate. Call once in the graphics/rendering loop. If the computer cannot keep up with the rate (i.e. drawing too slow), the delay is zero and the delay interpolation is reset.

Return time that passed since the last call to the procedure in ms. May return 0.