通过FFI调用Raylib时球拍中的SIGSEGV MAPERR

Question

我正在尝试通过FFI从球拍代码中使用Raylib (https://www.raylib.com/，https://github.com/raysan5/raylib)。下面是最简单的例子：

#lang racket
(require ffi/unsafe
         ffi/unsafe/define)

; raylib shared object must be available for Racket
; for example, in Linux it must be in
; ~/.racket/<racket-version>/lib> or /usr/lib/racket
(define-ffi-definer define-raylib (ffi-lib "libraylib" #:global? #t))

(define-raylib BeginDrawing (_fun  -> _void))
(define-raylib CloseWindow (_fun -> _void))
(define-raylib EndDrawing (_fun -> _void))
(define-raylib InitWindow (_fun _int _int _string -> _void))
(define-raylib SetTargetFPS (_fun _int -> _void))
(define-raylib WindowShouldClose (_fun -> _int))

(void InitWindow 640 480 "Test window")
(void SetTargetFPS 60)

(define (main-loop)
        (BeginDrawing)
        (EndDrawing)
        (if (= (WindowShouldClose) 0)
            (main-loop)
            (CloseWindow)))

(main-loop)

但是，即使是这个非常简单的示例也会崩溃，并显示以下消息：

SIGSEGV MAPERR si_code 1 fault on addr (nil)
Aborted (core dumped)

看起来它在调用BeginDrawing()函数时崩溃了。这个函数的代码也非常简单：

// Setup canvas (framebuffer) to start drawing
void BeginDrawing(void)
{
    currentTime = GetTime();            // Number of elapsed seconds since InitTimer()
    updateTime = currentTime - previousTime;
    previousTime = currentTime;

    rlLoadIdentity();                   // Reset current matrix (MODELVIEW)
    rlMultMatrixf(MatrixToFloat(downscaleView));       // If downscale required, apply it here
}

带有rl前缀的函数是OpenGL包装器。可能是OpenGL上下文问题？

我试着在Guile Scheme中调用相同的函数，在Guile中所有的函数都很好用。

Answer 1

看起来您实际上并没有调用InitWindow或SetFPS。

请尝试(InitWindow 640 480 "Test window")，而不是(void InitWindow 640 480 "Test window")。