如何使用PySDL2获取鼠标位置?

时间:2014-12-05 18:16:30

标签: python sdl pysdl2

除了通过监听事件之外,根本不了解如何获得鼠标的位置,但在事件队列为空的情况下,如何实现?

pysdl for pygamers的文档建议使用sdl2.mouse.SDL_GetMouseState()doc here),但此功能需要您要询问的光标的x,y坐标。同时,调用sdl2.mouse.SDL_GetCursor()会返回一个游标对象,但是我找不到从它获取坐标的方法(即它只是包装一个C对象,所以它有一个空的.__dict__属性)。

我一直在尝试我能想到的一切,但我以前从未在C中编程过。我试图制作的简单包装函数只是:

def mouse_pos(self):
            #  ideally, just return <some.path.to.mouse_x_y> 
            event_queue = sdl2.SDL_PumpEvents()
            state = sdl2.mouse.SDL_GetMouseState(None, None)  # just returns 0, so I tried the next few lines
            print state
            for event in event_queue:
                if event.type == sdl2.SDL_MOUSEMOTION:
            #  this works, except if the mouse hasn't moved yet, in which case it's none        
            return [event.x, event.y] 

2 个答案:

答案 0 :(得分:4)

SDL_GetMouseState()是SDL2 C函数的包装器。因此,您必须使用ctypes从中检索值。原始SDL2函数接收两个指针(x和y)来存储光标位置。

下面的代码段会为您做正确的事:

import ctypes
...
x, y = ctypes.c_int(0), ctypes.c_int(0) # Create two ctypes values
# Pass x and y as references (pointers) to SDL_GetMouseState()
buttonstate = sdl2.mouse.SDL_GetMouseState(ctypes.byref(x), ctypes.byref(y))
# Print x and y as "native" ctypes values
print(x, y)
# Print x and y as Python values
print(x.value, y.value)

`

答案 1 :(得分:0)

您还可以检查运动事件:

if event.type == sdl2.SDL_MOUSEMOTION:
    motion = event.motion
    print(motion.x, motion.xrel, motion.y, motion.yrel)