Question

我想知道使用SDL_GetWindowSize()的适当方法是什么。根据我得到的错误信息，我不应该使用WIDTH和HEIGHT，因为它们是整数。那么应该在他们的地方使用什么？

import sdl2

APP_SHORT_NAME = 'Test'
WIDTH = 400
HEIGHT = 400

sdl2.SDL_Init(sdl2.SDL_INIT_VIDEO)
window = sdl2.SDL_CreateWindow(
    APP_SHORT_NAME.encode('ascii'),
    sdl2.SDL_WINDOWPOS_UNDEFINED, sdl2.SDL_WINDOWPOS_UNDEFINED,
    WIDTH, HEIGHT, 0 )

sdlWindowsize = sdl2.SDL_GetWindowSize( window, WIDTH, HEIGHT )
print('sdlWindowsize = {0}'.format(sdlWindowsize))

错误消息：

Traceback (most recent call last):
  File "/home/sunbear/Coding/Vulkan/vulkan/MyProject/LunarG_cube_example/sdl2_window.py", line 13, in <module>
    sdlWindowsize = sdl2.SDL_GetWindowSize( window, WIDTH, HEIGHT )
ctypes.ArgumentError: argument 2: <class 'TypeError'>: expected LP_c_int instance instead of int

Answer 1

SDL_GetWindowSize需要3个参数 - 窗口和两个指向int的指针，它将保存结果值。它没有返回任何值。由于pysdl2使用ctypes，它应该是例如：

import sdl2
import ctypes

APP_SHORT_NAME = 'Test'
WIDTH = 400
HEIGHT = 400

sdl2.SDL_Init(sdl2.SDL_INIT_VIDEO)
window = sdl2.SDL_CreateWindow(
    APP_SHORT_NAME.encode('ascii'),
    sdl2.SDL_WINDOWPOS_UNDEFINED, sdl2.SDL_WINDOWPOS_UNDEFINED,
    WIDTH, HEIGHT, 0 )

w = ctypes.c_int()
h = ctypes.c_int()
sdl2.SDL_GetWindowSize( window, w, h)
print("w=%d h=%d" % (w.value, h.value))

应该为sdl2.SDL_GetWindowSize使用哪些函数参数？

1 个答案: