From f4c8a1908d768ac90431c1b5521796af8cc9752b Mon Sep 17 00:00:00 2001
From: Silver <silver@silv.re>
Date: Thu, 7 Apr 2022 00:17:21 +0100
Subject: [PATCH] gpu: fix BindGroup.Entry so that optional things are optional

---
 gpu/src/BindGroup.zig      |  6 ++---
 gpu/src/NativeInstance.zig | 53 ++++++++++++++++++--------------------
 2 files changed, 28 insertions(+), 31 deletions(-)

diff --git a/gpu/src/BindGroup.zig b/gpu/src/BindGroup.zig
index b082e775..8f81356d 100644
--- a/gpu/src/BindGroup.zig
+++ b/gpu/src/BindGroup.zig
@@ -30,11 +30,11 @@ pub inline fn setLabel(group: BindGroup, label: [:0]const u8) void {
 
 pub const Entry = struct {
     binding: u32,
-    buffer: Buffer,
+    buffer: ?Buffer,
     offset: u64,
     size: u64,
-    sampler: Sampler,
-    texture_view: TextureView,
+    sampler: ?Sampler,
+    texture_view: ?TextureView,
 };
 
 pub const Descriptor = struct {
diff --git a/gpu/src/NativeInstance.zig b/gpu/src/NativeInstance.zig
index 62acc7d8..5913e5a9 100644
--- a/gpu/src/NativeInstance.zig
+++ b/gpu/src/NativeInstance.zig
@@ -378,36 +378,33 @@ const device_vtable = Device.VTable{
     .createBindGroup = (struct {
         pub fn createBindGroup(ptr: *anyopaque, descriptor: *const BindGroup.Descriptor) BindGroup {
             var few_entries: [16]c.WGPUBindGroupEntry = undefined;
-            const entries = if (descriptor.entries.len <= 8) blk: {
-                for (descriptor.entries) |entry, i| {
-                    few_entries[i] = c.WGPUBindGroupEntry{
-                        .nextInChain = null,
-                        .binding = entry.binding,
-                        .buffer = @ptrCast(c.WGPUBuffer, entry.buffer.ptr),
-                        .offset = entry.offset,
-                        .size = entry.size,
-                        .sampler = @ptrCast(c.WGPUSampler, entry.sampler.ptr),
-                        .textureView = @ptrCast(c.WGPUTextureView, entry.texture_view.ptr),
-                    };
-                }
-                break :blk few_entries[0..descriptor.entries.len];
-            } else blk: {
-                const mem = std.heap.page_allocator.alloc(c.WGPUBindGroupEntry, descriptor.entries.len) catch unreachable;
-                for (descriptor.entries) |entry, i| {
-                    mem[i] = c.WGPUBindGroupEntry{
-                        .nextInChain = null,
-                        .binding = entry.binding,
-                        .buffer = @ptrCast(c.WGPUBuffer, entry.buffer.ptr),
-                        .offset = entry.offset,
-                        .size = entry.size,
-                        .sampler = @ptrCast(c.WGPUSampler, entry.sampler.ptr),
-                        .textureView = @ptrCast(c.WGPUTextureView, entry.texture_view.ptr),
-                    };
-                }
-                break :blk mem;
-            };
+            const entries = if (descriptor.entries.len <= 8)
+                few_entries[0..descriptor.entries.len]
+            else
+                std.heap.page_allocator.alloc(c.WGPUBindGroupEntry, descriptor.entries.len) catch unreachable;
             defer if (entries.len > 8) std.heap.page_allocator.free(entries);
 
+            for (descriptor.entries) |entry, i| {
+                entries[i] = c.WGPUBindGroupEntry{
+                    .nextInChain = null,
+                    .binding = entry.binding,
+                    .buffer = if (entry.buffer) |buf|
+                        @ptrCast(c.WGPUBuffer, buf.ptr)
+                    else
+                        null,
+                    .offset = entry.offset,
+                    .size = entry.size,
+                    .sampler = if (entry.sampler) |samp|
+                        @ptrCast(c.WGPUSampler, samp.ptr)
+                    else
+                        null,
+                    .textureView = if (entry.texture_view) |tex|
+                        @ptrCast(c.WGPUTextureView, tex.ptr)
+                    else
+                        null,
+                };
+            }
+
             const desc = c.WGPUBindGroupDescriptor{
                 .nextInChain = null,
                 .label = if (descriptor.label) |l| l else null,