From b5dad13bd7828bb18a73401ca6c9e78817d68273 Mon Sep 17 00:00:00 2001
From: peterino2 <peterlimail47@gmail.com>
Date: Sun, 26 Oct 2025 22:31:48 -0700
Subject: [PATCH] enabled parallel job, added optimizeBroadphase, and more
 scopes

---
 README.md                                     |  91 +++++++++++++-
 engine/core/src/scene.zig                     | 113 +++++++++++++++++-
 engine/physics/src/physicsSystem.zig          |   4 +
 projects/sampleGame/externGame/externGame.zig |   7 +-
 4 files changed, 207 insertions(+), 8 deletions(-)

diff --git a/README.md b/README.md
index 1f8dcda..a4400fa 100644
--- a/README.md
+++ b/README.md
@@ -1,14 +1,103 @@
 # Backlog
 
-
 zig version: 0.15.1
 
 Backlog Labs Game Engine.
 
+## Getting Started
+
 run tools/scripts/first-time-setup.py
 
 ffmpeg -i INPUT.mp4 -c:v libtheora -q:v 7 -c:a libvorbis -q:a 4 OUTPUT.ogv
 
+## git-bug Cheat Sheet
+
+This project uses git-bug for distributed issue tracking. Issues are stored directly in the repository.
+
+### Common Commands
+
+**Listing Issues**
+```bash
+git bug bug                    # List all issues
+git bug bug status:open        # List only open issues
+git bug bug status:closed      # List only closed issues
+```
+
+**Creating Issues**
+```bash
+git bug bug new -t "title" -m "message"              # Create new issue
+git bug bug new -t "Add feature X" -m "Description"  # Example
+```
+
+**Viewing & Managing Issues**
+```bash
+git bug bug show <id>          # Show issue details
+git bug bug comment <id>       # Add a comment to an issue
+git bug bug close <id>         # Close an issue
+git bug bug open <id>          # Reopen an issue
+git bug bug status <id>        # Show issue status
+```
+
+**Labels**
+```bash
+git bug bug label <id>              # Show labels for an issue
+git bug bug label new <id> <label>  # Add a label
+git bug bug label rm <id> <label>   # Remove a label
+```
+
+**Syncing**
+```bash
+git bug pull                   # Pull issue updates from remote
+git bug push                   # Push issue updates to remote
+```
+
+### Standard Labels
+
+**Component Labels**: `core`, `rendering`, `physics`, `build-system`, `platform`, `assets`, `audio`, `ui`, `documentation`
+
+**Type Labels**:
+- `bug` - Defects or incorrect behavior
+- `feature` - New functionality
+- `enhancement` - Improvements to existing features
+- `task` - General development work
+- `documentation` - Documentation improvements
+- `question` - Design decisions or discussions
+- `refactoring` - Code cleanup
+
+**Problem Type Labels** (for bugs):
+- `memory` - Memory issues
+- `threading` - Concurrency issues
+- `crash` - Application crashes
+- `build` - Build system issues
+
+### Quick Examples
+
+```bash
+# Create a bug report
+git bug bug new -t "Memory leak in asset loader" -m "Assets not freed when unloading scenes"
+git bug bug label new <id> bug assets memory
+
+# Create a feature request
+git bug bug new -t "Add terrain generation" -m "Implement heightmap-based terrain"
+git bug bug label new <id> feature rendering
+
+# Create a task
+git bug bug new -t "Update to Zig 0.15" -m "Migrate to latest Zig version"
+git bug bug label new <id> task build-system
+
+# View and comment on an issue
+git bug bug show abc123
+git bug bug comment abc123
+```
+
+### Tips
+
+- Issue IDs can be abbreviated (first few characters)
+- Use `--non-interactive` flag for scripting
+- Issues sync with `git bug pull/push`
+- Keep descriptions factual and clear
+
+---
 
 /// --------------------------------------------------------
 void* malloc(size_t size); // gives you a pointer to a memory buffer of size
diff --git a/engine/core/src/scene.zig b/engine/core/src/scene.zig
index 810b2e8..e963d4a 100644
--- a/engine/core/src/scene.zig
+++ b/engine/core/src/scene.zig
@@ -345,16 +345,23 @@ pub const SceneSystem = struct {
         repr.lastUpdate = self.tickCount;
     }
 
+    const useParallelJob = true;
+
     pub fn updateTransforms(self: *@This()) void {
         // todo. calculate a running load factor for the number of movable objects
         // vs static objects
         // if we have a small amount of movable vs static AND if we have > 1000 objects,
         // then iterate over dynamicObjects array instead
-        for (Scene.SceneObjectContainer.denseItems(._repr), 0..) |*repr, i| {
-            const settings = Scene.SceneObjectContainer.readDense(i, .settings);
-            if (settings.sceneMode == .moveable or repr.lastUpdate == 0) {
-                const posRot = Scene.SceneObjectContainer.readDense(i, .posRot);
-                self.updateTransform(repr, posRot);
+
+        if (useParallelJob) {
+            core.parallelJob(UpdateWorldTransformsJob{}, false, 6) catch unreachable;
+        } else {
+            for (Scene.SceneObjectContainer.denseItems(._repr), 0..) |*repr, i| {
+                const settings = Scene.SceneObjectContainer.readDense(i, .settings);
+                if (settings.sceneMode == .moveable or repr.lastUpdate == 0) {
+                    const posRot = Scene.SceneObjectContainer.readDense(i, .posRot);
+                    self.updateTransform(repr, posRot);
+                }
             }
         }
     }
@@ -427,6 +434,102 @@ pub const SceneSystem = struct {
     }
 };
 
+const UpdateWorldTransformsJob = struct {
+    world: ?*anyopaque = null,
+
+    pub fn func(self: @This(), thread: *core.ThreadContext) void {
+        const z = core.tracy.ZoneN(@src(), "Transform Hierarchy - wide");
+        defer z.End();
+        thread.barrier(@src()) catch unreachable;
+
+        const outputs = core.get(core.SceneSystem).getOutputForWorker(thread.threadId) catch return;
+        const outputList = core.get(core.SceneSystem).getOutputList(thread.threadId) catch return;
+
+        self.updateTransformsHierarchy(thread, outputs, outputList) catch |err| switch (err) {
+            error.OutOfMemory => {
+                unreachable;
+            },
+            // else => {
+            //     thread.abort(@src(), "unknown error", err);
+            //     return;
+            // },
+        };
+
+        const denseRepr = core.Scene.SceneObjectContainer.denseItems(._repr);
+
+        const z3 = core.tracy.ZoneN(@src(), "Merge Outputs");
+        // merge outputs
+        for (outputList.items) |outIndex| {
+            if (denseRepr[outIndex].merge.cmpxchgStrong(false, true, .seq_cst, .acquire) == null) {
+                denseRepr[outIndex].transform = outputs[outIndex];
+            }
+        }
+        z3.End();
+        thread.barrier(@src()) catch unreachable;
+    }
+
+    fn updateTransform(
+        self: @This(),
+        thread: *core.ThreadContext,
+        index: usize,
+        densePosRot: []core.scene.ScenePosRot,
+        denseRepr: []core.scene.SceneObjectRepr,
+        outputs: []core.math.Transform,
+        outputList: *std.ArrayList(usize),
+    ) void {
+        var final: core.Transform = core.zm.identity();
+
+        const repr = denseRepr[index];
+
+        if (repr.parent) |parent| {
+            if (core.Scene.SceneObjectContainer.sparseToDense(parent)) |parentIndex| {
+                self.updateTransform(thread, parentIndex, densePosRot, denseRepr, outputs, outputList);
+                const parentTransform = outputs[parentIndex];
+                final = parentTransform;
+            } else {}
+        }
+
+        const posRot = densePosRot[index];
+
+        outputs[index] = core.zm.mul(
+            core.zm.mul(
+                core.zm.mul(
+                    core.zm.scalingV(posRot.scale.toZm()),
+                    core.zm.matFromQuat(posRot.rotation.quat),
+                ),
+                core.zm.translationV(posRot.position.toZm()),
+            ),
+            final,
+        );
+
+        outputList.appendAssumeCapacity(index);
+    }
+
+    pub fn updateTransformsHierarchy(self: @This(), thread: *core.ThreadContext, outputs: []core.math.Transform, outputList: *std.ArrayList(usize)) !void {
+        const z = core.tracy.ZoneN(@src(), "updateTransformsHierarchy");
+        defer z.End();
+        //const dense = self.world.denseScenes();
+        const densePosRot = core.Scene.SceneObjectContainer.denseItems(.posRot);
+        const denseRepr = core.Scene.SceneObjectContainer.denseItems(._repr);
+
+        // everything allocated with thread.scratch is blown away when the thread is complete
+        // try outputs.resize(thread.scratch(), densePosRot.len);
+
+        // scan and mark all root nodes for update
+        const split = thread.splitSlice(core.scene.SceneObjectRepr, denseRepr);
+
+        // const locals:[]core.math.Transform = try thread.scratch().alloc(core.math.Transform, split.slice.len);
+
+        const z2 = core.tracy.ZoneN(@src(), "WalkAndResolve");
+        for (split.slice, 0..) |*repr, i| {
+            repr.merge.store(false, .seq_cst); // reset the merge big
+            const index = split.startIndex + i;
+            self.updateTransform(thread, index, densePosRot, denseRepr, outputs, outputList);
+        }
+        z2.End();
+    }
+};
+
 // LUA_BEGIN
 
 // because scene objects are a special sparse-multiset type,
diff --git a/engine/physics/src/physicsSystem.zig b/engine/physics/src/physicsSystem.zig
index 698e274..56e11b9 100644
--- a/engine/physics/src/physicsSystem.zig
+++ b/engine/physics/src/physicsSystem.zig
@@ -176,7 +176,9 @@ pub const PhysicsRuntime = struct {
         //     self.timeSinceUpdate -= self.updatePeriod;
         //     self.system.update(@floatCast(self.updatePeriod), .{}) catch unreachable;
         // }
+        var z = core.tracy.ZoneN(@src(), "physics system update ");
         self.system.update(@floatCast(dt), .{}) catch unreachable;
+        defer z.End();
 
         // todo.. interpolation kinda easy here.
         self.updateScenes(dt);
@@ -196,6 +198,8 @@ pub const PhysicsRuntime = struct {
         for (PhysicsCharacter.BaseContainer.list.items) |physChar| {
             physChar.update(dt);
         }
+        var z = core.tracy.ZoneN(@src(), "Updating physics transform");
+        defer z.End();
 
         // update physics colliders
         for (PhysicsCollider.BaseContainer.list.items) |collider| {
diff --git a/projects/sampleGame/externGame/externGame.zig b/projects/sampleGame/externGame/externGame.zig
index 59bd2ea..79ea41f 100644
--- a/projects/sampleGame/externGame/externGame.zig
+++ b/projects/sampleGame/externGame/externGame.zig
@@ -151,13 +151,14 @@ pub const ExternGameObject = struct {
         }
 
         // change this into a parallel for
-        for (0..4000) |i| {
+        for (0..400) |i| {
             _ = try core.get(core.GameObjectSystem).spawnObject(BoxObject, "Box", .{
                 .posRot = .{
-                    .position = .{ .x = core.itof32((i % 100)) * 2, .y = 15.0, .z = core.itof32(@divFloor(i, 100) * 2) },
+                    .position = .{ .x = core.itof32((i % 100)) * 2, .z = 15.0, .y = core.itof32(@divFloor(i, 100) * 2) },
                 },
             });
         }
+        physics.optimizeBroadPhase();
     }
 
     pub fn onMapReload(ctx: ?*anyopaque, _: core.ActionEvent) void {
@@ -448,6 +449,8 @@ pub const ExternGameObject = struct {
                     rend.context().lightPosition = p;
                 }
 
+                physics.applyForce(r.body, ray.dir.fmul(400), r.point);
+
                 // core.debugLine(ray.start, ray.start.add(ray.dir.fmul(1000)), .{ .duration = 2.5 });
                 // physics.applyForce(r.body, ray.dir.fmul(400), r.point);
             }