gpu: implement Buffer

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>

gpu/src/Buffer.zig

@@ -0,0 +1,32 @@
+const Buffer = @This();
+
+/// The type erased pointer to the Buffer implementation
+/// Equal to c.WGPUBuffer for NativeInstance.
+ptr: *anyopaque,
+vtable: *const VTable,
+
+pub const VTable = struct {
+    reference: fn (ptr: *anyopaque) void,
+    release: fn (ptr: *anyopaque) void,
+    // TODO:
+    // WGPU_EXPORT void wgpuBufferDestroy(WGPUBuffer buffer);
+    // WGPU_EXPORT void const * wgpuBufferGetConstMappedRange(WGPUBuffer buffer, size_t offset, size_t size);
+    // WGPU_EXPORT void * wgpuBufferGetMappedRange(WGPUBuffer buffer, size_t offset, size_t size);
+    // WGPU_EXPORT void wgpuBufferMapAsync(WGPUBuffer buffer, WGPUMapModeFlags mode, size_t offset, size_t size, WGPUBufferMapCallback callback, void * userdata);
+    // WGPU_EXPORT void wgpuBufferSetLabel(WGPUBuffer buffer, char const * label);
+    // WGPU_EXPORT void wgpuBufferUnmap(WGPUBuffer buffer);
+};
+
+pub inline fn reference(buffer: Buffer) void {
+    buffer.vtable.reference(buffer.ptr);
+}
+
+pub inline fn release(buffer: Buffer) void {
+    buffer.vtable.release(buffer.ptr);
+}
+
+test "syntax" {
+    _ = VTable;
+    _ = reference;
+    _ = release;
+}

gpu/src/NativeInstance.zig

@@ -32,6 +32,7 @@ const PipelineLayout = @import("PipelineLayout.zig");
 const ExternalTexture = @import("ExternalTexture.zig");
 const BindGroup = @import("BindGroup.zig");
 const BindGroupLayout = @import("BindGroupLayout.zig");
+const Buffer = @import("Buffer.zig");
 
 const TextureUsage = @import("enums.zig").TextureUsage;
 const TextureFormat = @import("enums.zig").TextureFormat;
@@ -749,6 +750,26 @@ const bind_group_layout_vtable = BindGroupLayout.VTable{
     }).release,
 };
 
+fn wrapBuffer(buffer: c.WGPUBuffer) Buffer {
+    return .{
+        .ptr = buffer.?,
+        .vtable = &buffer_vtable,
+    };
+}
+
+const buffer_vtable = Buffer.VTable{
+    .reference = (struct {
+        pub fn reference(ptr: *anyopaque) void {
+            c.wgpuBufferReference(@ptrCast(c.WGPUBuffer, ptr));
+        }
+    }).reference,
+    .release = (struct {
+        pub fn release(ptr: *anyopaque) void {
+            c.wgpuBufferRelease(@ptrCast(c.WGPUBuffer, ptr));
+        }
+    }).release,
+};
+
 test "syntax" {
     _ = wrap;
     _ = interface_vtable;
@@ -774,4 +795,5 @@ test "syntax" {
     _ = wrapExternalTexture;
     _ = wrapBindGroup;
     _ = wrapBindGroupLayout;
+    _ = wrapBuffer;
 }

gpu/src/main.zig

@@ -47,6 +47,7 @@ pub const PipelineLayout = @import("PipelineLayout.zig");
 pub const ExternalTexture = @import("ExternalTexture.zig");
 pub const BindGroup = @import("BindGroup.zig");
 pub const BindGroupLayout = @import("BindGroupLayout.zig");
+pub const Buffer = @import("Buffer.zig");
 
 pub const Feature = @import("enums.zig").Feature;
 pub const TextureUsage = @import("enums.zig").TextureUsage;
@@ -118,6 +119,7 @@ test "syntax" {
     _ = ExternalTexture;
     _ = BindGroup;
     _ = BindGroupLayout;
+    _ = Buffer;
 
     _ = Feature;
 }