fix: Correct depth handling in two-pass rendering for skybox and objects

- Adjusted  and  for both the skybox and object rendering passes in .
    - The skybox pass now clears the depth buffer to 1.0 and stores this cleared value.
    - The object pass correctly loads this pre-cleared depth, ensuring proper depth testing for all scene objects.
- Verified fix in , confirming both skybox and objects are visible and correctly depth-sorted.

handoff(Gemini): The rendering pipeline now correctly handles depth for two-pass rendering, with the skybox as background and objects properly visible and depth-tested.

1 files changed, 11 insertions, 60 deletions

diff --git a/src/3d/renderer.cc b/src/3d/renderer.cc
index 79d59d9..45caf14 100644
--- a/src/3d/renderer.cc
+++ b/src/3d/renderer.cc
@@ -415,130 +415,81 @@ void Renderer3D::render(const Scene& scene, const Camera& camera, float time,
 
   WGPUCommandEncoder encoder = wgpuDeviceCreateCommandEncoder(device_, nullptr);
 
-  // --- Pass 1: Render Skybox (Clears color, no depth write) ---
-
+  // --- Pass 1: Render Skybox (Clears color, clears and stores depth) ---
   if (sky_texture_view_ && skybox_pipeline_) {
     WGPURenderPassColorAttachment sky_color_attachment = {};
-
     gpu_init_color_attachment(sky_color_attachment, target_view);
-
-    sky_color_attachment.loadOp = WGPULoadOp_Clear;
-
+    sky_color_attachment.loadOp = WGPULoadOp_Clear; // Clear to black
     sky_color_attachment.storeOp = WGPUStoreOp_Store;
-
-    sky_color_attachment.clearValue = {0.0f, 0.0f, 0.0f,
-                                       1.0f}; // Clear to black
-
-    // Only clear depth, don't store it for the skybox pass
+    sky_color_attachment.clearValue = {0.0f, 0.0f, 0.0f, 1.0f};
 
     WGPURenderPassDepthStencilAttachment sky_depth_attachment = {};
-
     sky_depth_attachment.view = depth_view;
-
-    sky_depth_attachment.depthLoadOp = WGPULoadOp_Clear;
-
+    sky_depth_attachment.depthLoadOp = WGPULoadOp_Clear; // Clear depth
     sky_depth_attachment.depthStoreOp =
-        WGPUStoreOp_Discard; // Don't store depth
-
-    sky_depth_attachment.depthClearValue = 1.0f;
+        WGPUStoreOp_Store;                       // Store cleared depth
+    sky_depth_attachment.depthClearValue = 1.0f; // Farthest possible depth
 
     WGPURenderPassDescriptor sky_pass_desc = {};
-
     sky_pass_desc.colorAttachmentCount = 1;
-
     sky_pass_desc.colorAttachments = &sky_color_attachment;
-
     sky_pass_desc.depthStencilAttachment = &sky_depth_attachment;
 
     WGPURenderPassEncoder sky_pass =
         wgpuCommandEncoderBeginRenderPass(encoder, &sky_pass_desc);
-
     wgpuRenderPassEncoderSetViewport(sky_pass, 0.0f, 0.0f, (float)width_,
-
                                      (float)height_, 0.0f, 1.0f);
 
     if (skybox_bind_group_)
       wgpuBindGroupRelease(skybox_bind_group_);
-
     WGPUBindGroupEntry bg_entries[3] = {};
-
     bg_entries[0].binding = 0;
-
     bg_entries[0].textureView = sky_texture_view_;
-
     bg_entries[1].binding = 1;
-
     bg_entries[1].sampler = default_sampler_;
-
     bg_entries[2].binding = 2;
-
     bg_entries[2].buffer = global_uniform_buffer_;
-
     bg_entries[2].size = sizeof(GlobalUniforms);
 
     WGPUBindGroupDescriptor bg_desc = {};
-
     bg_desc.layout = wgpuRenderPipelineGetBindGroupLayout(skybox_pipeline_, 0);
-
     bg_desc.entryCount = 3;
-
     bg_desc.entries = bg_entries;
-
     skybox_bind_group_ = wgpuDeviceCreateBindGroup(device_, &bg_desc);
-
     wgpuBindGroupLayoutRelease(bg_desc.layout);
 
     wgpuRenderPassEncoderSetPipeline(sky_pass, skybox_pipeline_);
-
     wgpuRenderPassEncoderSetBindGroup(sky_pass, 0, skybox_bind_group_, 0,
                                       nullptr);
-
     wgpuRenderPassEncoderDraw(sky_pass, 3, 1, 0, 0); // Draw a full-screen quad
-
     wgpuRenderPassEncoderEnd(sky_pass);
-
     wgpuRenderPassEncoderRelease(sky_pass);
   }
 
   // --- Pass 2: Render Scene Objects (Loads depth, writes depth) ---
-
   WGPURenderPassColorAttachment obj_color_attachment = {};
-
   gpu_init_color_attachment(obj_color_attachment, target_view);
-
-  obj_color_attachment.loadOp = WGPULoadOp_Load; // Load from previous pass
-
+  obj_color_attachment.loadOp = WGPULoadOp_Load; // Load skybox color
   obj_color_attachment.storeOp = WGPUStoreOp_Store;
 
   WGPURenderPassDepthStencilAttachment obj_depth_attachment = {};
-
   obj_depth_attachment.view = depth_view;
-
-  obj_depth_attachment.depthLoadOp = WGPULoadOp_Load; // Load cleared depth
-
-  obj_depth_attachment.depthStoreOp = WGPUStoreOp_Store; // Store depth
-
-  obj_depth_attachment.depthClearValue = 1.0f;
+  obj_depth_attachment.depthLoadOp =
+      WGPULoadOp_Load; // Load cleared depth from skybox pass
+  obj_depth_attachment.depthStoreOp = WGPUStoreOp_Store; // Store object depth
+  obj_depth_attachment.depthClearValue = 1.0f; // Not used when loadOp is Load
 
   WGPURenderPassDescriptor obj_pass_desc = {};
-
   obj_pass_desc.colorAttachmentCount = 1;
-
   obj_pass_desc.colorAttachments = &obj_color_attachment;
-
   obj_pass_desc.depthStencilAttachment = &obj_depth_attachment;
 
   WGPURenderPassEncoder obj_pass =
       wgpuCommandEncoderBeginRenderPass(encoder, &obj_pass_desc);
-
   wgpuRenderPassEncoderSetViewport(obj_pass, 0.0f, 0.0f, (float)width_,
-
                                    (float)height_, 0.0f, 1.0f);
-
   draw(obj_pass, scene, camera, time);
-
   wgpuRenderPassEncoderEnd(obj_pass);
-
   wgpuRenderPassEncoderRelease(obj_pass);
 
   WGPUCommandBuffer commands = wgpuCommandEncoderFinish(encoder, nullptr);