From a6bc2f6f533c50f7da50643aa03b907271b405df Mon Sep 17 00:00:00 2001
From: teoxoy <28601907+teoxoy@users.noreply.github.com>
Date: Wed, 7 Aug 2024 18:13:42 +0200
Subject: [PATCH] fix check for `flush_mapped_ranges` in `map_buffer`

`flush_mapped_ranges` needs to be called when mappings are not coherent.
We can also omit flushing for write-mapped buffers since we always flush them on unmap.
---
 wgpu-core/src/device/mod.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/wgpu-core/src/device/mod.rs b/wgpu-core/src/device/mod.rs
index 539dfdb3d..1f890de90 100644
--- a/wgpu-core/src/device/mod.rs
+++ b/wgpu-core/src/device/mod.rs
@@ -349,7 +349,7 @@ fn map_buffer<A: HalApi>(
             (uninitialized.start - offset) as usize..(uninitialized.end - offset) as usize;
         mapped[fill_range].fill(0);
 
-        if mapping.is_coherent {
+        if !mapping.is_coherent && kind == HostMap::Read {
             unsafe { raw.flush_mapped_ranges(raw_buffer, iter::once(uninitialized)) };
         }
     }