feat: Implement 3D system and procedural texture manager

- Extended mini_math.h with mat4 multiplication and affine transforms.
- Implemented TextureManager for runtime procedural texture generation and GPU upload.
- Added 3D system components: Camera, Object, Scene, and Renderer3D.
- Created test_3d_render mini-demo for interactive 3D verification.
- Fixed WebGPU validation errors regarding depthSlice and unimplemented WaitAny.

1 files changed, 60 insertions, 0 deletions

diff --git a/src/3d/renderer.h b/src/3d/renderer.h
new file mode 100644
index 0000000..0dadc32
--- /dev/null
+++ b/src/3d/renderer.h
@@ -0,0 +1,60 @@
+// This file is part of the 64k demo project.
+// It defines the Renderer3D class.
+// Handles WebGPU pipeline creation and execution for 3D scenes.
+
+#pragma once
+
+#include "3d/camera.h"
+#include "3d/scene.h"
+#include "gpu/gpu.h"
+#include <vector>
+
+// Matches the GPU struct layout
+struct GlobalUniforms {
+  mat4 view_proj;
+  vec3 camera_pos;
+  float time;
+};
+
+// Matches the GPU struct layout
+struct ObjectData {
+  mat4 model;
+  vec4 color;
+  vec4 params; // Type, etc.
+};
+
+class Renderer3D {
+ public:
+  void init(WGPUDevice device, WGPUQueue queue, WGPUTextureFormat format);
+  void shutdown();
+
+  // Renders the scene to the given texture view
+  void render(const Scene& scene, const Camera& camera, float time,
+              WGPUTextureView target_view, WGPUTextureView depth_view_opt = nullptr);
+
+  // Resize handler (if needed for internal buffers)
+  void resize(int width, int height);
+
+ private:
+  void create_pipeline();
+  void create_default_resources();
+  void update_uniforms(const Scene& scene, const Camera& camera, float time);
+
+  WGPUDevice device_ = nullptr;
+  WGPUQueue queue_ = nullptr;
+  WGPUTextureFormat format_ = WGPUTextureFormat_Undefined;
+
+  WGPURenderPipeline pipeline_ = nullptr;
+  WGPUBindGroup bind_group_ = nullptr;
+  WGPUBuffer global_uniform_buffer_ = nullptr;
+  WGPUBuffer object_storage_buffer_ = nullptr;
+  
+  // Depth buffer management
+  WGPUTexture depth_texture_ = nullptr;
+  WGPUTextureView depth_view_ = nullptr;
+  int width_ = 0;
+  int height_ = 0;
+
+  // Max objects capacity
+  static const int kMaxObjects = 100;
+};