move everything to functions

src/main.cpp

@@ -12,6 +12,7 @@ static vr::ETrackingUniverseOrigin TRACKING_UNIVERSE = vr::ETrackingUniverseOrig
 
 uint16_t width;
 uint16_t height;
+bool should_exit = false;
 
 Display *xdisplay;
 Window root_window;
@@ -24,98 +25,119 @@ vr::Texture_t vr_texture;
 GLuint screen_texture;
 GLFWwindow *gl_window;
 
-void cleanup(int _sig = 0);
+void init_x11()
-
-int main(int argc, char **argv)
 {
-	signal(SIGINT, cleanup);
+	xdisplay = XOpenDisplay(nullptr);
+	assert(xdisplay != nullptr);
+	printf("Created X11 display\n");
+	root_window = XRootWindow(xdisplay, 0);
+	XWindowAttributes attributes;
+	XGetWindowAttributes(xdisplay, root_window, &attributes);
+	width = attributes.width;
+	height = attributes.height;
+}
+
+void init_glfw()
+{
+	assert(glfwInit() == true);
+	glfwWindowHint(GLFW_VISIBLE, false);
+	gl_window = glfwCreateWindow(width, height, "Overlay", nullptr, nullptr);
+	assert(gl_window != nullptr);
+	glfwMakeContextCurrent(gl_window);
+	printf("Created GLFW context\n");
+
+	glGenTextures(1, &screen_texture);
+	glBindTexture(GL_TEXTURE_2D, screen_texture);
+
+	vr_texture.eColorSpace = vr::EColorSpace::ColorSpace_Auto;
+	vr_texture.eType = vr::ETextureType::TextureType_OpenGL;
+	vr_texture.handle = (void *)(uintptr_t)screen_texture;
+}
+
+void init_vr()
+{
+	vr::EVRInitError init_err;
+	ovr_sys = vr::VR_Init(&init_err, vr::EVRApplicationType::VRApplication_Overlay);
+	assert(init_err == 0);
+	ovr_overlay = vr::VROverlay();
+	printf("Initialized openvr overlay\n");
+}
+
+void init_overlay()
+{
+	auto overlay_err = ovr_overlay->CreateOverlay("deskpot", "Desktop view", &main_overlay);
+	assert(overlay_err == 0);
+	ovr_overlay->ShowOverlay(main_overlay);
+	ovr_overlay->SetOverlayWidthInMeters(main_overlay, 2.5f);
+	uint8_t col[4] = {20, 50, 50, 255};
+	ovr_overlay->SetOverlayRaw(main_overlay, &col, 1, 1, 4);
+	printf("Created overlay instance\n");
+
+	vr::HmdMatrix34_t transform;
+	auto err = ovr_overlay->GetOverlayTransformAbsolute(main_overlay, &TRACKING_UNIVERSE, &transform);
+	assert(err == 0);
+	transform.m[1][1] = -1; // flip Y axis
+	err = ovr_overlay->SetOverlayTransformAbsolute(main_overlay, TRACKING_UNIVERSE, &transform);
+	assert(err == 0);
+}
+
+void cleanup()
+{
+	printf("\nShutting down\n");
+	vr::VR_Shutdown();
+	glfwDestroyWindow(gl_window);
+	glfwTerminate();
+	exit(0);
+}
+
+void render_desktop()
+{
+	auto frame = XGetImage(xdisplay, root_window, 0, 0, width, height, AllPlanes, ZPixmap);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_BGRA, GL_UNSIGNED_BYTE, frame->data);
+	XDestroyImage(frame);
+
+	auto set_err = ovr_overlay->SetOverlayTexture(main_overlay, &vr_texture);
+	// if (set_err)
+	// 	printf("error setting texture: %d\n", set_err);
+	assert(set_err == 0);
+}
+
+void update_cursor()
+{
+	int pix_x, pix_y;
 	{
-		xdisplay = XOpenDisplay(nullptr);
+		Window _t1;
-		assert(xdisplay != nullptr);
+		int _t2;
-		printf("Created X11 display\n");
+		unsigned int _t3;
-		root_window = XRootWindow(xdisplay, 0);
+		XQueryPointer(xdisplay, root_window, &_t1, &_t1, &pix_x, &pix_y, &_t2, &_t2, &_t3);
-		XWindowAttributes attributes;
-		XGetWindowAttributes(xdisplay, root_window, &attributes);
-		width = attributes.width;
-		height = attributes.height;
 	}
+	// TODO: make this work when aspect ratio is >1 (root window is taller than it is wide)
+	float ratio = (float)height / (float)width;
+	float top_edge = 0.5f - ratio / 2.0f;
+	float x = pix_x / (float)width;
+	float y = pix_y / (float)width + top_edge;
+	auto pos = vr::HmdVector2_t{x, y};
+	ovr_overlay->SetOverlayCursorPositionOverride(main_overlay, &pos);
+}
 
+void interrupted(int _sig)
+{
+	should_exit = true;
+}
+
+int main()
+{
+	init_x11();
+	init_glfw();
+	init_vr();
+	init_overlay();
+
+	signal(SIGINT, interrupted);
+
+	while (!should_exit)
 	{
-		assert(glfwInit() == true);
+		render_desktop();
-		glfwWindowHint(GLFW_VISIBLE, false);
+		update_cursor();
-		gl_window = glfwCreateWindow(width, height, "Overlay", nullptr, nullptr);
-		assert(gl_window != nullptr);
-		glfwMakeContextCurrent(gl_window);
-		printf("Created GLFW context\n");
-	}
-
-	{
-		vr::EVRInitError init_err;
-		ovr_sys = vr::VR_Init(&init_err, vr::EVRApplicationType::VRApplication_Overlay);
-		assert(init_err == 0);
-		ovr_overlay = vr::VROverlay();
-		printf("Initialized openvr overlay\n");
-	}
-
-	{
-		auto overlay_err = ovr_overlay->CreateOverlay("deskpot", "Desktop view", &main_overlay);
-		assert(overlay_err == 0);
-		ovr_overlay->ShowOverlay(main_overlay);
-		ovr_overlay->SetOverlayWidthInMeters(main_overlay, 2.5f);
-		uint8_t col[4] = {20, 50, 50, 255};
-		ovr_overlay->SetOverlayRaw(main_overlay, &col, 1, 1, 4);
-		printf("Created overlay instance\n");
-	}
-
-	{
-		vr::HmdMatrix34_t transform;
-		auto err = ovr_overlay->GetOverlayTransformAbsolute(main_overlay, &TRACKING_UNIVERSE, &transform);
-		assert(err == 0);
-		transform.m[1][1] = -1;
-		err = ovr_overlay->SetOverlayTransformAbsolute(main_overlay, TRACKING_UNIVERSE, &transform);
-		assert(err == 0);
-	}
-
-	{
-		glGenTextures(1, &screen_texture);
-		glBindTexture(GL_TEXTURE_2D, screen_texture);
-
-		vr_texture.eColorSpace = vr::EColorSpace::ColorSpace_Auto;
-		vr_texture.eType = vr::ETextureType::TextureType_OpenGL;
-		vr_texture.handle = (void *)(uintptr_t)screen_texture;
-	}
-
-	while (1)
-	{
-		auto frame = XGetImage(xdisplay, root_window, 0, 0, width, height, AllPlanes, ZPixmap);
-		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_BGRA, GL_UNSIGNED_BYTE, frame->data);
-		XDestroyImage(frame);
-
-		{
-			auto set_err = ovr_overlay->SetOverlayTexture(main_overlay, &vr_texture);
-			if (set_err)
-			{
-				printf("error setting texture: %d\n", set_err);
-				assert(set_err == 0);
-			}
-		}
-
-		{ // update cursor position
-			int pix_x, pix_y;
-			{
-				Window _t1;
-				int _t2;
-				unsigned int _t3;
-				XQueryPointer(xdisplay, root_window, &_t1, &_t1, &pix_x, &pix_y, &_t2, &_t2, &_t3);
-			}
-			// TODO: make this work when aspect ratio is >1 (root window is taller than it is wide)
-			float ratio = (float)height / (float)width;
-			float top_edge = 0.5f - ratio / 2.0f;
-			float x = pix_x / (float)width;
-			float y = pix_y / (float)width + top_edge;
-			auto pos = vr::HmdVector2_t{x, y};
-			ovr_overlay->SetOverlayCursorPositionOverride(main_overlay, &pos);
-		}
 
 		glfwSwapBuffers(gl_window);
 		usleep(1000000 / FRAMERATE);
@@ -123,13 +145,3 @@ int main(int argc, char **argv)
 	cleanup();
 	return 0;
 }
-
-void cleanup(int _sig)
-{
-	printf("\nCleaning up\n");
-	vr::VR_Shutdown();
-	glfwDestroyWindow(gl_window);
-	glfwTerminate();
-	printf("Shutting down\n");
-	exit(0);
-}