From b1f4243ccf71afcfd55e2be9338f115f4b69d156 Mon Sep 17 00:00:00 2001
From: hodasemi <michaelh.95@t-online.de>
Date: Fri, 20 Jan 2023 15:36:10 +0100
Subject: [PATCH] Add check for usage flag when writing to file

---
 vulkan-rs/src/image.rs | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/vulkan-rs/src/image.rs b/vulkan-rs/src/image.rs
index ed2596a..d2d7fe9 100644
--- a/vulkan-rs/src/image.rs
+++ b/vulkan-rs/src/image.rs
@@ -129,7 +129,7 @@ impl ImageBuilder {
                     layers: preinitialized_image.layers,
                     levels: 1,
                     sample_count: preinitialized_image.sample_count,
-                    _usage: preinitialized_image.usage,
+                    usage: preinitialized_image.usage,
                 });
 
                 // TODO: check necessity
@@ -414,7 +414,7 @@ impl ImageBuilder {
             layers: info.vk_image_create_info.arrayLayers,
             levels: info.vk_image_create_info.mipLevels,
             sample_count: info.vk_image_create_info.samples,
-            _usage: info.vk_image_create_info.usage,
+            usage: info.vk_image_create_info.usage,
         }))
     }
 
@@ -489,7 +489,7 @@ pub struct Image {
     layers: u32, // array layers
     levels: u32, // mip map levels
     sample_count: VkSampleCountFlagBits,
-    _usage: VkImageUsageFlagBits,
+    usage: VkImageUsageFlagBits,
 }
 
 impl Image {
@@ -779,6 +779,13 @@ impl Image {
     }
 
     pub fn to_file(self: &Arc<Image>, path: impl AsRef<Path>) -> Result<()> {
+        // check if image is created with correct usage flag that allows transfering data from it
+        if (self.usage | VK_IMAGE_USAGE_TRANSFER_SRC_BIT) == 0 {
+            return Err(anyhow::anyhow!(
+                "Image has not been create with VK_IMAGE_USAGE_TRANSFER_SRC_BIT flag!"
+            ));
+        }
+
         let buffer = self.copy_image_to_buffer()?;
         let memory = buffer.map_complete()?;