fix: Correct mesh normal transformation and floor shadow rendering

1 files changed, 11 insertions, 2 deletions

diff --git a/assets/final/shaders/render/scene_query_bvh.wgsl b/assets/final/shaders/render/scene_query_bvh.wgsl
index c7dfdf4..d040c1b 100644
--- a/assets/final/shaders/render/scene_query_bvh.wgsl
+++ b/assets/final/shaders/render/scene_query_bvh.wgsl
@@ -10,11 +10,13 @@ struct BVHNode {
 
 @group(0) @binding(2) var<storage, read> bvh_nodes: array<BVHNode>;
 
-fn get_dist(p: vec3<f32>, obj_type: f32) -> f32 {
+fn get_dist(p: vec3<f32>, obj_params: vec4<f32>) -> f32 {
+    let obj_type = obj_params.x;
     if (obj_type == 1.0) { return length(p) - 1.0; } // Unit Sphere
     if (obj_type == 2.0) { return sdBox(p, vec3<f32>(1.0)); } // Unit Box
     if (obj_type == 3.0) { return sdTorus(p, vec2<f32>(1.0, 0.4)); } // Unit Torus
     if (obj_type == 4.0) { return sdPlane(p, vec3<f32>(0.0, 1.0, 0.0), 0.0); }
+    if (obj_type == 5.0) { return sdBox(p, obj_params.yzw); } // MESH AABB
     return 100.0;
 }
 
@@ -40,7 +42,14 @@ fn map_scene(p: vec3<f32>, skip_idx: u32) -> f32 {
                 let obj = object_data.objects[obj_idx];
                 let q = (obj.inv_model * vec4<f32>(p, 1.0)).xyz;
                 let s = min(length(obj.model[0].xyz), min(length(obj.model[1].xyz), length(obj.model[2].xyz)));
-                d = min(d, get_dist(q, obj.params.x) * s);
+                // IMPORTANT: Plane (type 4.0) should not be scaled by 's' in this way.
+                // The sdPlane function expects its own scale/offset implicitly handled by the model matrix.
+                // The 's' factor is meant for primitives whose SDFs are defined relative to a unit size.
+                if (obj.params.x != 4.0) { // Only scale if not a plane
+                    d = min(d, get_dist(q, obj.params) * s);
+                } else {
+                    d = min(d, get_dist(q, obj.params));
+                }
             } else { // Internal
                 if (stack_ptr < 31) {
                     stack[stack_ptr] = node.left_idx;