bb intersection fix

experiments/tesst.scm

@@ -75,7 +75,18 @@
 
 (translate (vector 2 -6 0))
 (texture 0)
+
+(identity)
 (define a (build-cube))
 (define b (with-state (parent a) (build-cube)))
 (define c (build-cube))
 (with-primitive b (parent c))
+
+(with-primitive
+ a
+ (recalc-bb)
+ (msg "bb/point-intersect? 1=" (bb/point-intersect? (vector 0 0 0) 0))
+ (msg "bb/point-intersect? 0=" (bb/point-intersect? (vector 10 0 0) 0))
+ (translate (vector 10 0 0))
+ (msg "bb/point-intersect? 1=" (bb/point-intersect? (vector 10 0 0) 0))
+ )

src/engine/engine.cpp

@@ -526,7 +526,7 @@ bool engine::bb_point_intersect(const vec3 &p, flx_real threshold)
         scenenode *n = grabbed_node();
         if (n && n->m_primitive!=NULL)
         {
-            vec3 pt=n->m_tx.transform(p);
+            vec3 pt=n->m_tx.inverse().transform(p);
             return n->m_primitive->intersect_bb(pt,threshold);
         }
     }

src/engine/primitive.cpp

@@ -25,7 +25,8 @@
 
 #include "cube.h"
 
-primitive::primitive(unsigned int size, type t)
+primitive::primitive(unsigned int size, type t) :
+    m_bb_empty(true)
 {
     #ifndef _EE
     switch (t)
@@ -57,7 +58,8 @@ void primitive::build()
     m_tex=get_pdata_arr("t");
 }
 
-primitive::primitive()
+primitive::primitive():
+    m_bb_empty(true)
 {
     m_size=12*3;
 #ifndef _EE
@@ -172,14 +174,26 @@ void primitive::recalc_bb()
 {
     for (int i=0; i<m_size; i++)
     {
-        if (m_bbmin>m_positions[i]) m_bbmin=m_positions[i];
-        if (m_bbmax<m_positions[i]) m_bbmax=m_positions[i];
+        if (m_bb_empty)
+        {
+            m_bbmin=m_positions[i];
+            m_bbmax=m_positions[i];
+            m_bb_empty=false;
+        }
+
+        if (m_positions[i].x<m_bbmin.x) m_bbmin.x=m_positions[i].x;
+        if (m_positions[i].y<m_bbmin.y) m_bbmin.y=m_positions[i].y;
+        if (m_positions[i].z<m_bbmin.z) m_bbmin.z=m_positions[i].z;
+
+        if (m_positions[i].x>=m_bbmax.x) m_bbmax.x=m_positions[i].x;
+        if (m_positions[i].y>=m_bbmax.y) m_bbmax.y=m_positions[i].y;
+        if (m_positions[i].z>=m_bbmax.z) m_bbmax.z=m_positions[i].z;
     }
 }
 
 bool primitive::intersect_bb(const vec3 &p, flx_real threshold)
 {
-    return intersect_point_bb(p, m_bbmin, m_bbmin, threshold);
+    return intersect_point_bb(p, m_bbmin, m_bbmax, threshold);
 }
 
 list *primitive::intersect(const vec3 &start, const vec3 &end)

src/engine/primitive.h

@@ -69,6 +69,7 @@ protected:
     u32 m_size;
     list m_pdata;
 
+    bool m_bb_empty;
     vec3 m_bbmin;
     vec3 m_bbmax;