Win32: Add glfwAttachWin32Window

Related to #25.

tests/CMakeLists.txt

@@ -39,6 +39,12 @@ add_executable(timeout WIN32 MACOSX_BUNDLE timeout.c ${GLAD})
 add_executable(title WIN32 MACOSX_BUNDLE title.c ${GLAD})
 add_executable(windows WIN32 MACOSX_BUNDLE windows.c ${GETOPT} ${GLAD})
 
+if (WIN32)
+    add_executable(native WIN32 native.c ${GLAD})
+else()
+    message(FATAL_ERROR "This branch only makes sense on Win32 at the moment")
+endif()
+
 target_link_libraries(empty "${CMAKE_THREAD_LIBS_INIT}")
 target_link_libraries(threads "${CMAKE_THREAD_LIBS_INIT}")
 if (RT_LIBRARY)
@@ -46,7 +52,7 @@ if (RT_LIBRARY)
     target_link_libraries(threads "${RT_LIBRARY}")
 endif()
 
-set(WINDOWS_BINARIES empty gamma icon inputlag joysticks opacity tearing
+set(WINDOWS_BINARIES empty gamma icon inputlag joysticks native opacity tearing
                      threads timeout title windows)
 set(CONSOLE_BINARIES clipboard events msaa glfwinfo iconify monitors reopen
                      cursor)

tests/native.c

@@ -0,0 +1,116 @@
+//========================================================================
+// Win32 native handle attachment test
+// Copyright (c) Camilla Löwy <elmindreda@glfw.org>
+//
+// This software is provided 'as-is', without any express or implied
+// warranty. In no event will the authors be held liable for any damages
+// arising from the use of this software.
+//
+// Permission is granted to anyone to use this software for any purpose,
+// including commercial applications, and to alter it and redistribute it
+// freely, subject to the following restrictions:
+//
+// 1. The origin of this software must not be misrepresented; you must not
+//    claim that you wrote the original software. If you use this software
+//    in a product, an acknowledgment in the product documentation would
+//    be appreciated but is not required.
+//
+// 2. Altered source versions must be plainly marked as such, and must not
+//    be misrepresented as being the original software.
+//
+// 3. This notice may not be removed or altered from any source
+//    distribution.
+//
+//========================================================================
+
+#define UNICODE
+
+#include <glad/glad.h>
+#include <GLFW/glfw3.h>
+#define GLFW_EXPOSE_NATIVE_WIN32
+#include <GLFW/glfw3native.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+
+static void error_callback(int error, const char* description)
+{
+    fprintf(stderr, "Error: %s\n", description);
+}
+
+static void framebuffer_size_callback(GLFWwindow* window, int width, int height)
+{
+    glViewport(0, 0, width, height);
+}
+
+static LRESULT CALLBACK windowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
+{
+    // This will only be used until glfwAttachWin32Window
+    return DefWindowProcW(hWnd, uMsg, wParam, lParam);
+}
+
+int main(void)
+{
+    GLFWwindow* window;
+    WNDCLASSEX wc;
+    HWND handle;
+
+    ZeroMemory(&wc, sizeof(wc));
+    wc.cbSize        = sizeof(wc);
+    wc.style         = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;
+    wc.lpfnWndProc   = (WNDPROC) windowProc;
+    wc.hInstance     = GetModuleHandleW(NULL);
+    wc.hCursor       = LoadCursorW(NULL, IDC_ARROW);
+    wc.lpszClassName = L"SomeKindOfWindowClassName";
+
+    if (!RegisterClassExW(&wc))
+        exit(EXIT_FAILURE);
+
+    handle = CreateWindowExW(WS_EX_APPWINDOW,
+                             L"SomeKindOfWindowClassName",
+                             L"HWND attachment test",
+                             WS_OVERLAPPEDWINDOW | WS_VISIBLE,
+                             CW_USEDEFAULT, CW_USEDEFAULT,
+                             600, 400,
+                             NULL,
+                             NULL,
+                             GetModuleHandleW(NULL),
+                             NULL);
+
+    if (!handle)
+        exit(EXIT_FAILURE);
+
+    glfwSetErrorCallback(error_callback);
+
+    if (!glfwInit())
+    {
+        DestroyWindow(handle);
+        exit(EXIT_FAILURE);
+    }
+
+    window = glfwAttachWin32Window(handle, NULL);
+    if (!window)
+    {
+        glfwTerminate();
+        DestroyWindow(handle);
+        exit(EXIT_FAILURE);
+    }
+
+    glfwMakeContextCurrent(window);
+    gladLoadGLLoader((GLADloadproc) glfwGetProcAddress);
+    glfwSwapInterval(1);
+
+    glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
+
+    while (!glfwWindowShouldClose(window))
+    {
+        glClear(GL_COLOR_BUFFER_BIT);
+        glfwSwapBuffers(window);
+        glfwWaitEvents();
+    }
+
+    glfwTerminate();
+    DestroyWindow(handle);
+    exit(EXIT_SUCCESS);
+}
+