Add tracy profiling

build.zig

@@ -4,6 +4,9 @@ pub fn build(b: *std.Build) void {
     const target = b.standardTargetOptions(.{});
     const optimize = b.standardOptimizeOption(.{});
 
+    // tracy profiling (run with -Dtracy=true)
+    const enable_tracy = b.option(bool, "tracy", "Enable Tracy profiler") orelse false;
+
     const raylib_dep = b.dependency("raylib_zig", .{
         .target = target,
         .optimize = optimize,
@@ -24,6 +27,16 @@ pub fn build(b: *std.Build) void {
     sandbox_exe.root_module.addImport("raylib", raylib_dep.module("raylib"));
     sandbox_exe.linkLibrary(raylib_dep.artifact("raylib"));
 
+    // tracy integration (optional)
+    const ztracy = b.dependency("ztracy", .{
+        .enable_ztracy = enable_tracy,
+        .on_demand = true, // allow connecting after app starts
+    });
+    sandbox_exe.root_module.addImport("ztracy", ztracy.module("root"));
+    if (enable_tracy) {
+        sandbox_exe.linkLibrary(ztracy.artifact("tracy"));
+    }
+
     b.installArtifact(sandbox_exe);
 
     const sandbox_run_cmd = b.addRunArtifact(sandbox_exe);

build.zig.zon

@@ -7,6 +7,10 @@
             .url = "git+https://github.com/raylib-zig/raylib-zig#a4d18b2d1cf8fdddec68b5b084535fca0475f466",
             .hash = "raylib_zig-5.6.0-dev-KE8REL5MBQAf3p497t52Xw9P7ojndIkVOWPXnLiLLw2P",
         },
+        .ztracy = .{
+            .url = "git+https://github.com/zig-gamedev/ztracy?ref=main#e7b401dea9ce006f8b236e3a2ca1a9f3d5c3e896",
+            .hash = "ztracy-0.14.0-dev-zHJSq78GGQC904aYvBPn6OOvRVOq_opAwDfeHZdvQyej",
+        },
     },
     .paths = .{
         "build.zig",

justfile

@@ -42,7 +42,7 @@ check:
 test:
     zig build test
 
-# auto-benchmark (ramps entities until performance degrades, works on linux/windows)
+# auto-benchmark (ramps entities until performance degrades)
 bench:
     zig build -Doptimize=ReleaseFast run -- --bench
     cat benchmark.log
@@ -58,3 +58,8 @@ bench-sw:
 bench-sw:
     @echo "bench-sw: windows doesn't have xvfb equivalent"
     @echo "use 'just bench' if you have a GPU, or run in WSL/linux CI"
+
+[linux]
+profile port="9876":
+  # start Tracy: tracy-profiler -a 127.0.0.1 -p {{port}}
+  zig build -Dtracy=true -Doptimize=ReleaseFast && TRACY_PORT={{port}} ./zig-out/bin/sandbox

src/sandbox_main.zig

@@ -3,6 +3,7 @@
 
 const std = @import("std");
 const rl = @import("raylib");
+const ztracy = @import("ztracy");
 const sandbox = @import("sandbox.zig");
 const ui = @import("ui.zig");
 const SsboRenderer = @import("ssbo_renderer.zig").SsboRenderer;
@@ -331,12 +332,16 @@ pub fn main() !void {
 
         // update
         if (!paused) {
+            const tracy_update = ztracy.ZoneN(@src(), "update");
+            defer tracy_update.End();
             const update_start = std.time.microTimestamp();
             sandbox.update(&entities, &rng);
             update_time_us = std.time.microTimestamp() - update_start;
         }
 
         // render
+        const tracy_render = ztracy.ZoneN(@src(), "render");
+        defer tracy_render.End();
         const render_start = std.time.microTimestamp();
 
         rl.beginDrawing();
@@ -407,6 +412,9 @@ pub fn main() !void {
         const update_ms = @as(f32, @floatFromInt(update_time_us)) / 1000.0;
         const render_ms = @as(f32, @floatFromInt(render_time_us)) / 1000.0;
         logger.log(elapsed, entities.count, frame_ms, update_ms, render_ms);
+
+        // tracy frame mark
+        ztracy.FrameMark();
     }
 }
 

src/ssbo_renderer.zig

@@ -3,6 +3,7 @@
 
 const std = @import("std");
 const rl = @import("raylib");
+const ztracy = @import("ztracy");
 const sandbox = @import("sandbox.zig");
 
 const SCREEN_WIDTH = sandbox.SCREEN_WIDTH;
@@ -142,6 +143,9 @@ pub const SsboRenderer = struct {
         rl.gl.rlDrawRenderBatchActive();
 
         // copy entity data to GPU buffer (position + color only)
+        {
+            const zone = ztracy.ZoneN(@src(), "ssbo_copy");
+            defer zone.End();
             for (entities.items[0..entities.count], 0..) |entity, i| {
                 self.gpu_buffer[i] = .{
                     .x = entity.x,
@@ -149,10 +153,15 @@ pub const SsboRenderer = struct {
                     .color = entity.color,
                 };
             }
+        }
 
         // upload to SSBO
+        {
+            const zone = ztracy.ZoneN(@src(), "ssbo_upload");
+            defer zone.End();
             const data_size: u32 = @intCast(entities.count * @sizeOf(sandbox.GpuEntity));
             rl.gl.rlUpdateShaderBuffer(self.ssbo_id, self.gpu_buffer.ptr, data_size, 0);
+        }
 
         // bind shader
         rl.gl.rlEnableShader(self.shader_id);
@@ -183,9 +192,13 @@ pub const SsboRenderer = struct {
         rl.gl.rlSetBlendMode(@intFromEnum(rl.gl.rlBlendMode.rl_blend_alpha));
 
         // bind VAO and draw
+        {
+            const zone = ztracy.ZoneN(@src(), "ssbo_draw");
+            defer zone.End();
             _ = rl.gl.rlEnableVertexArray(self.vao_id);
             rl.gl.rlEnableVertexBuffer(self.vbo_id);
             rl.gl.rlDrawVertexArrayInstanced(0, 6, @intCast(entities.count));
+        }
 
         // cleanup - restore raylib's expected state
         rl.gl.rlDisableVertexArray();