add wait API call

include/Refresh.h

@@ -1417,6 +1417,11 @@ REFRESHAPI void REFRESH_Submit(
 	uint32_t commandBufferCount
 );
 
+/* Waits for the previous submission to complete. */
+REFRESHAPI void REFRESH_Wait(
+	REFRESH_Device *device
+);
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */

src/Refresh.c

@@ -972,4 +972,13 @@ void REFRESH_Submit(
     );
 }
 
+void REFRESH_Wait(
+    REFRESH_Device *device
+) {
+    NULL_RETURN(device);
+    device->Wait(
+        device->driverData
+    );
+}
+
 /* vim: set noexpandtab shiftwidth=8 tabstop=8: */

src/Refresh_Driver.h

@@ -564,6 +564,10 @@ struct REFRESH_Device
         uint32_t commandBufferCount
     );
 
+    void(*Wait)(
+        REFRESH_Renderer *driverData
+    );
+
 	/* Opaque pointer for the Driver */
 	REFRESH_Renderer *driverData;
 };
@@ -622,7 +626,8 @@ struct REFRESH_Device
     ASSIGN_DRIVER_FUNC(BindComputeTextures, name) \
     ASSIGN_DRIVER_FUNC(AcquireCommandBuffer, name) \
     ASSIGN_DRIVER_FUNC(QueuePresent, name) \
-    ASSIGN_DRIVER_FUNC(Submit, name)
+    ASSIGN_DRIVER_FUNC(Submit, name) \
+    ASSIGN_DRIVER_FUNC(Wait, name)
 
 typedef struct REFRESH_Driver
 {

src/Refresh_Driver_Vulkan.c

@@ -8501,6 +8501,20 @@ static void VULKAN_Submit(
 	SDL_stack_free(commandBuffers);
 }
 
+static void VULKAN_Wait(
+    REFRESH_Renderer *driverData
+) {
+	VulkanRenderer *renderer = (VulkanRenderer*) driverData;
+
+	renderer->vkWaitForFences(
+		renderer->logicalDevice,
+		1,
+		&renderer->inFlightFence,
+		VK_TRUE,
+		UINT64_MAX
+	);
+}
+
 /* Device instantiation */
 
 static inline uint8_t VULKAN_INTERNAL_SupportsExtension(