Create function for image creation

gpu.h

@@ -20,8 +20,8 @@ typedef struct {
 	uint32_t swapchain_img_count;
 	VkImageView swapchain_img_views[MAX_FRAMES_IN_FLIGHT];
 	VkImage depth_img;
-	VkDeviceMemory depth_img_mem;
-	VkImageView depth_img_view;
+	VkDeviceMemory depth_mem;
+	VkImageView depth_view;
 	VkFramebuffer framebuffers[MAX_FRAMES_IN_FLIGHT];
 	VkShaderModule floor_vert_shader;
 	VkShaderModule model_vert_shader;