From 3a796c22446ff0248953a538b7cc4e080f979979 Mon Sep 17 00:00:00 2001
From: Dzmitry Malyshau <kvark@fastmail.com>
Date: Mon, 28 Jun 2021 23:43:40 -0400
Subject: [PATCH] hal/gles: fix buffer mapping

---
 wgpu-hal/src/gles/device.rs      | 54 ++++++++++++++------------------
 wgpu-hal/src/vulkan/instance.rs  |  8 +++--
 wgpu-hal/src/vulkan/mod.rs       |  1 -
 wgpu/examples/boids/compute.wgsl |  6 ++--
 4 files changed, 31 insertions(+), 38 deletions(-)

diff --git a/wgpu-hal/src/gles/device.rs b/wgpu-hal/src/gles/device.rs
index ff51975b5..1dd1f1d00 100644
--- a/wgpu-hal/src/gles/device.rs
+++ b/wgpu-hal/src/gles/device.rs
@@ -306,16 +306,17 @@ impl crate::Device<super::Api> for super::Device {
             glow::ARRAY_BUFFER
         };
 
-        let mut map_flags = 0;
-        if desc
+        let is_host_visible = desc
             .usage
-            .intersects(crate::BufferUse::MAP_READ | crate::BufferUse::MAP_WRITE)
-        {
+            .intersects(crate::BufferUse::MAP_READ | crate::BufferUse::MAP_WRITE);
+        let is_coherent = desc
+            .memory_flags
+            .contains(crate::MemoryFlag::PREFER_COHERENT);
+        let mut map_flags = 0;
+
+        if is_host_visible {
             map_flags |= glow::MAP_PERSISTENT_BIT;
-            if desc
-                .memory_flags
-                .contains(crate::MemoryFlag::PREFER_COHERENT)
-            {
+            if is_coherent {
                 map_flags |= glow::MAP_COHERENT_BIT;
             }
         }
@@ -335,6 +336,11 @@ impl crate::Device<super::Api> for super::Device {
         gl.buffer_storage(target, raw_size, None, map_flags);
         gl.bind_buffer(target, None);
 
+        if !is_coherent && desc.usage.contains(crate::BufferUse::MAP_WRITE) {
+            map_flags |= glow::MAP_FLUSH_EXPLICIT_BIT;
+        }
+        //TODO: do we need `glow::MAP_UNSYNCHRONIZED_BIT`?
+
         if let Some(label) = desc.label {
             if gl.supports_debug() {
                 gl.object_label(glow::BUFFER, raw, Some(label));
@@ -361,17 +367,13 @@ impl crate::Device<super::Api> for super::Device {
         let gl = &self.shared.context;
 
         let is_coherent = buffer.map_flags & glow::MAP_COHERENT_BIT != 0;
-        let mut flags = buffer.map_flags | glow::MAP_UNSYNCHRONIZED_BIT;
-        if !is_coherent {
-            flags |= glow::MAP_FLUSH_EXPLICIT_BIT;
-        }
 
         gl.bind_buffer(buffer.target, Some(buffer.raw));
         let ptr = gl.map_buffer_range(
             buffer.target,
             range.start as i32,
             (range.end - range.start) as i32,
-            flags,
+            buffer.map_flags,
         );
         gl.bind_buffer(buffer.target, None);
 
@@ -401,19 +403,8 @@ impl crate::Device<super::Api> for super::Device {
             );
         }
     }
-    unsafe fn invalidate_mapped_ranges<I>(&self, buffer: &super::Buffer, ranges: I)
-    where
-        I: Iterator<Item = crate::MemoryRange>,
-    {
-        let gl = &self.shared.context;
-        gl.bind_buffer(buffer.target, Some(buffer.raw));
-        for range in ranges {
-            gl.invalidate_buffer_sub_data(
-                buffer.target,
-                range.start as i32,
-                (range.end - range.start) as i32,
-            );
-        }
+    unsafe fn invalidate_mapped_ranges<I>(&self, _buffer: &super::Buffer, _ranges: I) {
+        //TODO: do we need to do anything?
     }
 
     unsafe fn create_texture(
@@ -592,11 +583,6 @@ impl crate::Device<super::Api> for super::Device {
         let gl = &self.shared.context;
 
         let raw = gl.create_sampler().unwrap();
-        if let Some(label) = desc.label {
-            if gl.supports_debug() {
-                gl.object_label(glow::SAMPLER, raw, Some(label));
-            }
-        }
 
         let (min, mag) =
             conv::map_filter_modes(desc.min_filter, desc.mag_filter, desc.mipmap_filter);
@@ -652,6 +638,12 @@ impl crate::Device<super::Api> for super::Device {
             );
         }
 
+        if let Some(label) = desc.label {
+            if gl.supports_debug() {
+                gl.object_label(glow::SAMPLER, raw, Some(label));
+            }
+        }
+
         Ok(super::Sampler { raw })
     }
     unsafe fn destroy_sampler(&self, sampler: super::Sampler) {
diff --git a/wgpu-hal/src/vulkan/instance.rs b/wgpu-hal/src/vulkan/instance.rs
index 584435d65..1f046ec02 100644
--- a/wgpu-hal/src/vulkan/instance.rs
+++ b/wgpu-hal/src/vulkan/instance.rs
@@ -287,10 +287,14 @@ impl super::Instance {
     }
 }
 
-impl Drop for super::Instance {
+impl Drop for super::InstanceShared {
     fn drop(&mut self) {
         unsafe {
-            self.shared.raw.destroy_instance(None);
+            if let Some(du) = self.debug_utils.take() {
+                du.extension
+                    .destroy_debug_utils_messenger(du.messenger, None);
+            }
+            self.raw.destroy_instance(None);
         }
     }
 }
diff --git a/wgpu-hal/src/vulkan/mod.rs b/wgpu-hal/src/vulkan/mod.rs
index dd27836c7..133bb21f9 100644
--- a/wgpu-hal/src/vulkan/mod.rs
+++ b/wgpu-hal/src/vulkan/mod.rs
@@ -48,7 +48,6 @@ impl crate::Api for Api {
 
 struct DebugUtils {
     extension: ext::DebugUtils,
-    #[allow(dead_code)]
     messenger: vk::DebugUtilsMessengerEXT,
 }
 
diff --git a/wgpu/examples/boids/compute.wgsl b/wgpu/examples/boids/compute.wgsl
index bddb260a2..e0c6e9e71 100644
--- a/wgpu/examples/boids/compute.wgsl
+++ b/wgpu/examples/boids/compute.wgsl
@@ -41,8 +41,6 @@ fn main([[builtin(global_invocation_id)]] global_invocation_id: vec3<u32>) {
   var cMassCount : i32 = 0;
   var cVelCount : i32 = 0;
 
-  var pos : vec2<f32>;
-  var vel : vec2<f32>;
   var i : u32 = 0u;
   loop {
     if (i >= total) {
@@ -52,8 +50,8 @@ fn main([[builtin(global_invocation_id)]] global_invocation_id: vec3<u32>) {
       continue;
     }
 
-    pos = particlesSrc.particles[i].pos;
-    vel = particlesSrc.particles[i].vel;
+    let pos = particlesSrc.particles[i].pos;
+    let vel = particlesSrc.particles[i].vel;
 
     if (distance(pos, vPos) < params.rule1Distance) {
       cMass = cMass + pos;