Refactor

2 files changed, 79 insertions, 40 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3192c6a..e63816d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,8 @@
 cmake_minimum_required(VERSION 3.2)
 project(vkpugltest LANGUAGES C)
 
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -g")
+
 set(pugldir "../../pugl")
 set(PUGL_INCLUDE "${pugldir}")
 set(PUGL_LIBDIR "${pugldir}/build")
diff --git a/main.c b/main.c
index fb81e89..e0d2451 100644
--- a/main.c
+++ b/main.c
@@ -83,8 +83,10 @@ struct VulkanAPI {
 	PFN_vkEnumerateDeviceExtensionProperties	vkEnumerateDeviceExtensionProperties;
 };
 
+/** Vulkan application that uses Pugl for windows and events */
 struct RenderVulkan {
 	struct VulkanAPI *api;
+	PuglWorld *world;
 	char *errMsg;
 	VkInstance			instance;
 	VkDebugReportCallbackEXT	debugCallback;
@@ -121,12 +123,12 @@ const char *rvkGetErrMsg(struct RenderVulkan *vk)
 
 #if defined(_WIN32)
 #define VULKAN_SONAME_LATEST	"vulkan-1.dll"
-void *appDlopen(const char *soname)
+static inline void *appDlopen(const char *soname)
 {
 	return LoadLibraryA(soname);
 }
 
-char *appDlerror()
+static inline char *appDlerror()
 {
 	// TODO: Print a more informative string. Error codes are annoying.
 	DWORD errCode = GetLastError();
@@ -135,34 +137,39 @@ char *appDlerror()
 	return errStr;
 }
 
-void *appDlsym(void *handle, const char *symbol)
+static inline void *appDlsym(void *handle, const char *symbol)
 {
 	const uintptr_t ulAddr = (uintptr_t)GetProcAddress(handle, symbol);
 	return (void*)ulAddr;
 }
 
-int appDlclose(void *handle)
+static inline int appDlclose(void *handle)
 {
 	return FreeLibrary(handle);
 }
 
-void getRequiredInstanceExtensions(PuglWorld *world,
-		unsigned *pExtensionCount,
+PuglStatus getRequiredInstanceExtensions(PuglWorld *world,
+		uint32_t *pExtensionCount,
 		const char **const ppExtensionNames)
 {
-	(void)world;
+	if (!world) {
+		if (pExtensionCount) *pExtensionCount = 0;
+		if (ppExtensionNames) *ppExtensionNames = NULL;
+		return PUGL_FAILURE;
+	}
 	static const char *const required[] = {
 		VK_KHR_SURFACE_EXTENSION_NAME,
 		VK_KHR_WIN32_SURFACE_EXTENSION_NAME
 	};
-	static const unsigned num = sizeof(required) / sizeof(required[0]);
+	static const uint32_t num = sizeof(required) / sizeof(required[0]);
 	if (ppExtensionNames) {
-		for (int i = 0; i < num; ++i) {
+		for (uint32_t i = 0; i < num; ++i) {
 			ppExtensionNames[i] = required[i];
 		}
 	} else {
 		*pExtensionCount = num;
 	}
+	return PUGL_SUCCESS;
 }
 
 VkResult createVulkanSurface(PuglView *view,
@@ -184,36 +191,31 @@ VkResult createVulkanSurface(PuglView *view,
 #else
 #define VULKAN_SONAME_LATEST	"libvulkan.so.1"
 #include <dlfcn.h>
-// XXX: puglDlopen()
-void *appDlopen(const char *soname)
+// XXX: puglDlopen() and friends
+static inline void *appDlopen(const char *soname)
 {
 	return dlopen(soname, RTLD_NOW);
 }
 
-char *appDlerror()
+static inline char *appDlerror()
 {
 	return dlerror();
 }
 
-void *appDlsym(void *handle, const char *symbol)
+static inline void *appDlsym(void *handle, const char *symbol)
 {
 	return dlsym(handle, symbol);
 }
 
-int appDlclose(void *handle)
+static inline int appDlclose(void *handle)
 {
 	return dlclose(handle);
 }
 
 /* XXX:  puglGetRequiredInstanceExtensions()
- *       This will return the platform-specific names of the instance level
- *       extensions required to display images to the screen.
- *       Vulkan is off-screen by default and can be used without presenting
- *       at all, so off-screen applications will not need to call this
- *       function. In other words:
- *
- *       "Get the names of the required instance extensions if you want to
- *        display your images to the screen."
+ *       "Get the platform-specific names of the required instance-level 
+ *        extensions if you want to display your images to the screen."
+ *       Reminder that Vulkan is off-screen by default.
  *
  * TODO: Linux actually has three possible surfaces: Xlib, XCB, and Wayland.
  *       This should be figured out at runtime (without using #ifdefs).
@@ -222,27 +224,38 @@ int appDlclose(void *handle)
  *       variable should be left in the function signature for forward
  *       compatibility.
  */
-void getRequiredInstanceExtensions(PuglWorld *world,
-		unsigned *pExtensionCount,
+PuglStatus getRequiredInstanceExtensions(PuglWorld *world,
+		uint32_t *pExtensionCount,
 		const char **const ppExtensionNames)
 {
-	(void)world;
+	if (!world) {
+		if (pExtensionCount) *pExtensionCount = 0;
+		if (ppExtensionNames) *ppExtensionNames = NULL;
+		return PUGL_FAILURE;
+	}
+	// TODO: if (world->system == X11) { ... } else if (world->system == Wayland) { ... } else ...
 	static const char *const required[] = {
 		VK_KHR_SURFACE_EXTENSION_NAME,
 		VK_KHR_XLIB_SURFACE_EXTENSION_NAME
 	};
-	static const unsigned num = sizeof(required) / sizeof(required[0]);
+	static const uint32_t num = sizeof(required) / sizeof(required[0]);
 	if (ppExtensionNames) {
-		for (int i = 0; i < num; ++i) {
+		for (uint32_t i = 0; i < num; ++i) {
 			ppExtensionNames[i] = required[i];
 		}
 	} else {
 		*pExtensionCount = num;
 	}
+	return PUGL_SUCCESS;
 }
 
 /* XXX: puglCreateVulkanSurface()
- *      No need to wrap VkFreeSurfaceKHR()
+ *
+ *      Creating a surface is platform-specific and should be handled by Pugl
+ *      with this function exposed publicly.
+ *
+ *      No need to wrap vkFreeSurfaceKHR(). Creating a surface is platform
+ *      specific, but freeing it is not.
  */
 VkResult createVulkanSurface(PuglView *view,
 		VkInstance instance,
@@ -312,13 +325,13 @@ static VkResult createInstance(struct RenderVulkan *vk,
 	/* MoltenVK for macOS currently only supports Vulkan 1.0 */
 	appInfo.apiVersion = VK_MAKE_VERSION(1, 0, 0);
 
-	unsigned i, j, nRequired;
-	getRequiredInstanceExtensions(NULL, &nRequired, NULL);
+	uint32_t i, j, nRequired;
+	getRequiredInstanceExtensions(vk->world, &nRequired, NULL);
 
 	const uint32_t nExtensions = nRequired + nAdditional;
 	const char **const extensions = malloc(sizeof(const char*) * nExtensions);
 
-	getRequiredInstanceExtensions(NULL, NULL, extensions);
+	getRequiredInstanceExtensions(vk->world, NULL, extensions);
 	for (i = nRequired, j = 0; i < nExtensions; ++i, ++j) {
 		extensions[i] = additionalExtensions[j];
 	}
@@ -375,11 +388,24 @@ void rvkDestroy(struct RenderVulkan *vk)
 
 /** Create a self-contained Vulkan instance and set up a debug reporter
  *
+ * XXX
+ *
+ * At the moment `world` is not used for anything, but if/when Pugl supports
+ * dynamically choosing a backend (X11, XCB, Wayland), it is anticipated that
+ * `world` will contain information regarding which is in use, which will then
+ * be used by `createVulkanSurface`.
+ *
+ * If creating a surface is handled by Pugl (`puglCreateVulkanSurface`), then
+ * `PuglWorld` can remain completely opaque to the application.
+ *
+ * `world` is NOT internally managed by the application. It MUST be destroyed
+ * separately.
+ *
  * If errors occurred, the struct will be returned in an unusable state,
  * and MUST be checked via `rvkGetErrMsg`. It MUST then be destroyed via
  * `rvkDestroy`.
  * */
-struct RenderVulkan *rvkCreate()
+struct RenderVulkan *rvkCreate(PuglWorld *world)
 {
 	static const char *const instanceLayers[] = {
 		"VK_LAYER_LUNARG_standard_validation"
@@ -391,6 +417,11 @@ struct RenderVulkan *rvkCreate()
 	const uint32_t nInstanceExtensions = sizeof(instanceExtensions) / sizeof(instanceExtensions[0]);
 
 	struct RenderVulkan *vk = calloc(1, sizeof(*vk));
+	if (!world) {
+		rvkSetErrMsg(vk, "No PuglWorld provided");
+		return vk;
+	}
+	vk->world = world;
 	vk->api = calloc(1, sizeof(*vk->api));
 
 	vk->api->handle = loadVulkanLibrary(NULL);
@@ -570,14 +601,12 @@ static void rvkCreateSurface(struct RenderVulkan *vk, PuglView *view)
  *
  * Because this application will load all resources before any rendering begins,
  * and the amount of resources are small enough to be loaded almost instantly,
- * it will not make use of a separate TRANSFER queue family. This application
- * will also not attempt to find the "most powerful" device on the system, and
- * will choose the first suitable device it finds.
+ * it will not make use of a separate TRANSFER queue family.
  *
  * Information for many devices is available online at
  * https://vulkan.gpuinfo.org/
  */
-static int isDeviceSuitable(const struct RenderVulkan *const vk,
+static int rvkIsDeviceSuitable(const struct RenderVulkan *const vk,
 		const VkPhysicalDevice physicalDevice,
 		uint32_t *const graphicsIndex)
 {
@@ -622,6 +651,11 @@ static int isDeviceSuitable(const struct RenderVulkan *const vk,
 	return 1;
 }
 
+/** Selects a physical device
+ *
+ * This application will not attempt to find the "most powerful" device on the
+ * system, and will choose the first suitable device it finds.
+ */
 void rvkSelectPhysicalDevice(struct RenderVulkan *vk)
 {
 	if (!vk->surface) {
@@ -663,7 +697,7 @@ void rvkSelectPhysicalDevice(struct RenderVulkan *vk)
 	for (i = 0; i < nDevices; ++i) {
 		printf("Checking suitability for\t`%s`...\n", deviceProperties[i].deviceName);
 		uint32_t graphicsIndex;
-		if (isDeviceSuitable(vk, devices[i], &graphicsIndex)) {
+		if (rvkIsDeviceSuitable(vk, devices[i], &graphicsIndex)) {
 			printf("Using physical device:\t\t`%s`\n", deviceProperties[i].deviceName);
 			vk->deviceProperties = deviceProperties[i];
 			vk->physicalDevice = devices[i];
@@ -712,19 +746,21 @@ int main()
 	/* The Mesa Vulkan drivers require this to be called */
 	XInitThreads();
 #endif
+	PuglWorld *world = puglNewWorld();
 	const char *errMsg = NULL;
-	struct RenderVulkan *vk = rvkCreate();
+
+	/** Vulkan application that uses Pugl for windows and events */
+	struct RenderVulkan *vk = rvkCreate(world);
 	rvkCheckFatal(vk);
 
 	printf("Created Vulkan Instance Successfully\n");
 
-	PuglWorld *world = puglNewWorld();
 	PuglView *view = puglNewView(world);
 	const PuglRect frame = { 0, 0, 800, 600 };
 	puglSetBackend(view, puglStubBackend());
 
 	PuglStatus status;
-	if ((status = puglCreateWindow(view, "Pugl Vulkan Test"))) {
+	if ((status = puglCreateWindow(view, "Vulkan Application Using Pugl"))) {
 		fprintf(stderr, "Could not create window: %d\n", status);
 		rvkDestroy(vk);
 		puglFreeWorld(world);
@@ -746,6 +782,7 @@ int main()
 
 	puglFreeView(view);
 	puglFreeWorld(world);
+	/* Vulkan library MUST be unloaded AFTER call to XCloseDisplay() or it will segfault */
 	rvkDestroy(vk);
 	return 0;
 }