From 17f3c174dc898539521c7bbbdc3454a56c2dc3de Mon Sep 17 00:00:00 2001
From: Stephen Gutekanst <stephen@hexops.com>
Date: Mon, 11 Jul 2022 08:56:33 -0700
Subject: [PATCH] gpu: add MapMode flagset

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>
---
 gpu/TODO-webgpu.h  |  8 --------
 gpu/src/Buffer.zig |  2 +-
 gpu/src/types.zig  | 22 +++++++++++++++++++++-
 3 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/gpu/TODO-webgpu.h b/gpu/TODO-webgpu.h
index bf985f9d..25ac186e 100644
--- a/gpu/TODO-webgpu.h
+++ b/gpu/TODO-webgpu.h
@@ -1,13 +1,5 @@
 typedef uint32_t WGPUFlags;
 
-typedef enum WGPUMapMode {
-    WGPUMapMode_None = 0x00000000,
-    WGPUMapMode_Read = 0x00000001,
-    WGPUMapMode_Write = 0x00000002,
-    WGPUMapMode_Force32 = 0x7FFFFFFF
-} WGPUMapMode;
-typedef WGPUFlags WGPUMapModeFlags;
-
 typedef enum WGPUShaderStage {
     WGPUShaderStage_None = 0x00000000,
     WGPUShaderStage_Vertex = 0x00000001,
diff --git a/gpu/src/Buffer.zig b/gpu/src/Buffer.zig
index b1153828..586f5698 100644
--- a/gpu/src/Buffer.zig
+++ b/gpu/src/Buffer.zig
@@ -40,6 +40,6 @@ pub const Usage = packed struct {
     }
 
     pub fn equal(a: Usage, b: Usage) bool {
-        return @truncate(u10, @bitCast(u32, a)) == @truncate(u10, @bitCast(u32, b)) ;
+        return @truncate(u10, @bitCast(u32, a)) == @truncate(u10, @bitCast(u32, b));
     }
 };
diff --git a/gpu/src/types.zig b/gpu/src/types.zig
index bd2f3223..422f59f4 100644
--- a/gpu/src/types.zig
+++ b/gpu/src/types.zig
@@ -319,7 +319,27 @@ pub const ColorWriteMask = packed struct {
     };
 
     pub fn equal(a: ColorWriteMask, b: ColorWriteMask) bool {
-        return @truncate(u4, @bitCast(u32, a)) == @truncate(u4, @bitCast(u32, b)) ;
+        return @truncate(u4, @bitCast(u32, a)) == @truncate(u4, @bitCast(u32, b));
+    }
+};
+
+pub const MapMode = packed struct {
+    read: bool = false,
+    write: bool = false,
+
+    _padding: u30 = 0,
+
+    comptime {
+        std.debug.assert(
+            @sizeOf(@This()) == @sizeOf(u32) and
+                @bitSizeOf(@This()) == @bitSizeOf(u32),
+        );
+    }
+
+    pub const undef = MapMode{};
+
+    pub fn equal(a: ColorWriteMask, b: ColorWriteMask) bool {
+        return @truncate(u2, @bitCast(u32, a)) == @truncate(u2, @bitCast(u32, b));
     }
 };