From f5e6976937b7ee5b2078c75d442d31f5becc8a19 Mon Sep 17 00:00:00 2001
From: Stephen Gutekanst <stephen@hexops.com>
Date: Fri, 11 Mar 2022 19:36:21 -0700
Subject: [PATCH] gpu: make ConstantEntry & ColorTargetState C ABI compatible

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>
---
 gpu/src/NativeInstance.zig | 16 ++++++++--------
 gpu/src/structs.zig        |  6 ++++--
 2 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/gpu/src/NativeInstance.zig b/gpu/src/NativeInstance.zig
index 9182fa5e..cfe8a5c2 100644
--- a/gpu/src/NativeInstance.zig
+++ b/gpu/src/NativeInstance.zig
@@ -411,10 +411,10 @@ inline fn convertRenderPipelineDescriptor(
         .nextInChain = null,
         .module = @ptrCast(c.WGPUShaderModule, d.fragment.module.ptr),
         .entryPoint = d.vertex.entry_point,
-        .constantCount = 0, // d.fragment.constants.len,
-        .constants = null, // TODO: need to convert entire list to WGPUConstantEntry
-        .targetCount = 0, // d.fragment.targets.len,
-        .targets = null, // TODO: need to convert entire list to WGPUColorTargetState
+        .constantCount = @intCast(u32, d.fragment.constants.len),
+        .constants = @ptrCast(*const c.WGPUConstantEntry, &d.fragment.constants[0]),
+        .targetCount = @intCast(u32, d.fragment.targets.len),
+        .targets = @ptrCast(*const c.WGPUColorTargetState, &d.fragment.targets[0]),
     };
 
     return c.WGPURenderPipelineDescriptor{
@@ -425,10 +425,10 @@ inline fn convertRenderPipelineDescriptor(
             .nextInChain = null,
             .module = @ptrCast(c.WGPUShaderModule, d.vertex.module.ptr),
             .entryPoint = d.vertex.entry_point,
-            .constantCount = 0, // d.vertex.constants.len,
-            .constants = null, // TODO: need to convert entire list to WGPUConstantEntry
-            .bufferCount = 0, // d.vertex.buffers.len
-            .buffers = null, // TODO: need to convert entire list to WGPUVertexBufferLayout
+            .constantCount = @intCast(u32, d.vertex.constants.len),
+            .constants = @ptrCast(*const c.WGPUConstantEntry, &d.vertex.constants[0]),
+            .bufferCount = @intCast(u32, d.vertex.buffers.len),
+            .buffers = @ptrCast(*const c.WGPUVertexBufferLayout, &d.vertex.buffers[0]),
         },
         .primitive = c.WGPUPrimitiveState{
             .nextInChain = null,
diff --git a/gpu/src/structs.zig b/gpu/src/structs.zig
index b87dc625..cc88a0f9 100644
--- a/gpu/src/structs.zig
+++ b/gpu/src/structs.zig
@@ -69,7 +69,8 @@ pub const DepthStencilState = struct {
 };
 
 // TODO: how does this map to browser API?
-pub const ConstantEntry = struct {
+pub const ConstantEntry = extern struct {
+    reserved: ?*anyopaque = null,
     key: [*:0]const u8,
     value: f64,
 };
@@ -129,7 +130,8 @@ pub const FragmentState = struct {
     targets: []const ColorTargetState,
 };
 
-pub const ColorTargetState = struct {
+pub const ColorTargetState = extern struct {
+    reserved: ?*anyopaque = null,
     format: Texture.Format,
     blend: *const BlendState,
     write_mask: ColorWriteMask,