fix(3d): Distinguish floor grid from object textures

- Switched floor back to PLANE type in test_3d_render.
- Updated fragment shader to apply grid pattern ONLY to PLANE objects.
- Restored noise-based bump mapping and texturing for BOX and other SDF primitives.
- Verified correct visual appearance of floating cubes (no fixed grid).

2 files changed, 9 insertions, 6 deletions

diff --git a/src/3d/renderer.cc b/src/3d/renderer.cc
index 8676db4..d39aac0 100644
--- a/src/3d/renderer.cc
+++ b/src/3d/renderer.cc
@@ -254,7 +254,7 @@ fn fs_main(in: VertexOutput) -> @location(0) vec4<f32> {
         normal = normalize(transpose(normal_matrix) * n_local);
 
         // Apply texture to SDF color
-        if (obj_type == 2.0) { // BOX (used for floor)
+        if (obj_type == 4.0) { // PLANE (used for floor)
             let uv_grid = p.xz * 0.5;
             let grid = 0.5 + 0.5 * sin(uv_grid.x * 3.14) * sin(uv_grid.y * 3.14);
             let grid_val = smoothstep(0.45, 0.55, grid);
diff --git a/src/tests/test_3d_render.cc b/src/tests/test_3d_render.cc
index 9f046f9..a6db71b 100644
--- a/src/tests/test_3d_render.cc
+++ b/src/tests/test_3d_render.cc
@@ -137,10 +137,10 @@ void setup_scene() {
   g_scene.clear();
   srand(12345); // Fixed seed
 
-  // Large floor, use BOX type (SDF) for receiving shadows
-  Object3D floor(ObjectType::BOX);
+  // Large floor, use PLANE type
+  Object3D floor(ObjectType::PLANE);
   floor.position = vec3(0, -2.0f, 0);
-  floor.scale = vec3(25.0f, 0.2f, 25.0f);
+  floor.scale = vec3(25.0f, 1.0f, 25.0f); // Thicker for proxy hull safety
   floor.color = vec4(0.8f, 0.8f, 0.8f, 1.0f);
   g_scene.add_object(floor);
 
@@ -172,8 +172,11 @@ void setup_scene() {
     float dist = 3.0f + (rand() % 100) * 0.05f; // Closer to center
     float height = 0.5f + (rand() % 100) * 0.04f;
     obj.position = vec3(std::cos(angle) * dist, height, std::sin(angle) * dist);
-    float s = 0.6f + (rand() % 100) * 0.008f; // Larger
-    obj.scale = vec3(s, s, s);
+
+    // Random non-uniform scale for debugging
+    float s = 0.6f + (rand() % 100) * 0.008f;
+    obj.scale = vec3(s, s * 1.2f, s * 0.8f);
+
     obj.color = vec4((rand() % 100) / 100.0f, (rand() % 100) / 100.0f,
                      (rand() % 100) / 100.0f, 1.0f);
     g_scene.add_object(obj);