gpu: implement RenderPassEncoder.setIndexBuffer

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

gpu/src/NativeInstance.zig

@@ -41,6 +41,7 @@ const ComputePassEncoder = @import("ComputePassEncoder.zig");
 const ComputePipeline = @import("ComputePipeline.zig");
 
 const PresentMode = @import("enums.zig").PresentMode;
+const IndexFormat = @import("enums.zig").IndexFormat;
 
 const NativeInstance = @This();
 
@@ -1014,6 +1015,23 @@ const render_pass_encoder_vtable = RenderPassEncoder.VTable{
             );
         }
     }).setBlendConstant,
+    .setIndexBuffer = (struct {
+        pub fn setIndexBuffer(
+            ptr: *anyopaque,
+            buffer: Buffer,
+            format: IndexFormat,
+            offset: u64,
+            size: u64,
+        ) void {
+            c.wgpuRenderPassEncoderSetIndexBuffer(
+                @ptrCast(c.WGPURenderPassEncoder, ptr),
+                @ptrCast(c.WGPUBuffer, buffer.ptr),
+                @enumToInt(format),
+                offset,
+                size,
+            );
+        }
+    }).setIndexBuffer,
 };
 
 fn wrapRenderBundleEncoder(enc: c.WGPURenderBundleEncoder) RenderBundleEncoder {

gpu/src/RenderPassEncoder.zig

@@ -7,6 +7,7 @@ const Buffer = @import("Buffer.zig");
 const RenderBundle = @import("RenderBundle.zig");
 const BindGroup = @import("BindGroup.zig");
 const Color = @import("data.zig").Color;
+const IndexFormat = @import("enums.zig").IndexFormat;
 
 const RenderPassEncoder = @This();
 
@@ -38,8 +39,7 @@ pub const VTable = struct {
     pushDebugGroup: fn (ptr: *anyopaque, group_label: [*:0]const u8) void,
     setBindGroup: fn (ptr: *anyopaque, group_index: u32, group: BindGroup, dynamic_offsets: []u32) void,
     setBlendConstant: fn (ptr: *anyopaque, color: *const Color) void,
-    // setIndexBuffer: fn (ptr: *anyopaque, buffer: Buffer, format: IndexFormat, offset: u64, size: u64) void,
-    // WGPU_EXPORT void wgpuRenderPassEncoderSetIndexBuffer(WGPURenderPassEncoder renderPassEncoder, WGPUBuffer buffer, WGPUIndexFormat format, uint64_t offset, uint64_t size);
+    setIndexBuffer: fn (ptr: *anyopaque, buffer: Buffer, format: IndexFormat, offset: u64, size: u64) void,
     setLabel: fn (ptr: *anyopaque, label: [:0]const u8) void,
     setPipeline: fn (ptr: *anyopaque, pipeline: RenderPipeline) void,
     // setScissorRect: fn (ptr: *anyopaque, x: u32, y: u32, width: u32, height: u32) void,
@@ -132,6 +132,16 @@ pub inline fn setBlendConstant(pass: RenderPassEncoder, color: *const Color) voi
     pass.vtable.setBlendConstant(pass.ptr, color);
 }
 
+pub inline fn setIndexBuffer(
+    pass: RenderPassEncoder,
+    buffer: Buffer,
+    format: IndexFormat,
+    offset: u64,
+    size: u64,
+) void {
+    pass.vtable.setIndexBuffer(pass.ptr, buffer, format, offset, size);
+}
+
 pub inline fn setLabel(pass: RenderPassEncoder, label: [:0]const u8) void {
     pass.vtable.setLabel(pass.ptr, label);
 }
@@ -165,6 +175,7 @@ test {
     _ = pushDebugGroup;
     _ = setBindGroup;
     _ = setBlendConstant;
+    _ = setIndexBuffer;
     _ = setLabel;
     _ = setPipeline;
     _ = Descriptor;