fix(3d): Resolve missing shadows on floor plane

- Switched floor from rasterized CUBE to SDF PLANE for consistent shadow mapping.
- Implemented skip_idx in map_scene to properly prevent self-shadowing.
- Standardized soft shadow logic with improved bias and step size.
- Increased object elevation and adjusted light direction for more visible shadows.
- Enabled debug boxes in test_3d_render.

1 files changed, 12 insertions, 8 deletions

diff --git a/src/tests/test_3d_render.cc b/src/tests/test_3d_render.cc
index 3084edc..141b1b7 100644
--- a/src/tests/test_3d_render.cc
+++ b/src/tests/test_3d_render.cc
@@ -137,18 +137,18 @@ void setup_scene() {
   g_scene.clear();
   srand(12345); // Fixed seed
 
-  // Large floor, use CUBE type to exclude from SDF calculations
-  Object3D floor(ObjectType::CUBE);
+  // Large floor, use PLANE type
+  Object3D floor(ObjectType::PLANE);
   floor.position = vec3(0, -2.0f, 0);
-  floor.scale = vec3(20.0f, 0.5f, 20.0f);
+  floor.scale = vec3(100.0f, 1.0f, 100.0f);
   floor.color =
       vec4(0.9f, 0.9f, 0.9f, 1.0f); // Brighter white for better shadow contrast
   g_scene.add_object(floor);
 
   // Center object
   Object3D center(ObjectType::TORUS);
-  center.position = vec3(0, 0, 0);
-  center.scale = vec3(1.5f, 1.5f, 1.5f);
+  center.position = vec3(0, 1.0f, 0); // Higher
+  center.scale = vec3(2.5f, 2.5f, 2.5f); // Larger
   center.color = vec4(1, 0, 0, 1);
   g_scene.add_object(center);
 
@@ -163,12 +163,12 @@ void setup_scene() {
 
     Object3D obj(type);
     float angle = (rand() % 360) * 0.01745f;
-    float dist = 3.0f + (rand() % 100) * 0.05f;
-    float height = -1.0f + (rand() % 100) * 0.04f;
+    float dist = 4.0f + (rand() % 100) * 0.06f;
+    float height = 0.5f + (rand() % 100) * 0.04f; // Higher
 
     obj.position = vec3(std::cos(angle) * dist, height, std::sin(angle) * dist);
 
-    float s = 0.3f + (rand() % 100) * 0.005f;
+    float s = 0.5f + (rand() % 100) * 0.005f;
     obj.scale = vec3(s, s, s);
 
     obj.color = vec4((rand() % 100) / 100.0f, (rand() % 100) / 100.0f,
@@ -242,6 +242,10 @@ int main(int argc, char** argv) {
       g_scene.objects[i].position.y = std::sin(time * 3.0f + i) * 1.5f;
     }
 
+#if !defined(STRIP_ALL)
+    Renderer3D::SetDebugEnabled(true);
+#endif
+
     WGPUSurfaceTexture surface_tex;
     wgpuSurfaceGetCurrentTexture(g_surface, &surface_tex);
     if (surface_tex.status ==